Document mmy1R3gNDg1wapqb3wBoJ48pO

FROM (NAME & LOCATION M. F. BABER - ST. LOUIS DATE SUBJECT REFERENCE TO Howard Bergen (memo of May 5)> Bill Richard, and others have suggested there may be opportunities for our Business Group in the field of high per formance dielectric materials. The purpose of this memo is to present some background information concerning this field, which can serve as a starting point for future discussions on possible actions by our Business Group. Scores of new materials are being investigated today concerning their use in the electrical industry as high performance, and especially high temperature, dielectric materials. A few of these, such as aromatic- polyamides (Nomex, etc.) and polyimides are already being consumed in substantial quantities. Also, these are the two materials in which Monsanto has developed some capabilities. Howard Bergen also mentioned polycarbonates and polysulfones in his May 5 memorandum. These four materials are discussed later in this memorandum. Dielectric materials are marketed in many forms. Some of these would include wire coatings, impregnants, foams, molding powder, and films. Our group supplies dielectric fluids. The PP&R Division supplies dielectric materials in almost all other forms, except as films. (Monsanto also does not supply encapsulating and potting compounds. Epoxies are dominating this field, and Monsanto has no position ' in epoxies). The major new business opportunity for the Functional Fluids Business~Group, concerning solid aieiectric materials, appears to be the producTibh~arid sae of plastic dielectric films. If we were to enter this $ipu m plus business^ we probably would have to become a significant factor in the market, and supply a family of dielectric films based on Monsanto polymer technology. . DSW 200302 STLCOPCB4058366 -2- The remainder of this memo is in three parts. First, some background information is presented on high temperature dielectric materials, since many of these are supplied as films. . Then five separate materials are discussed, including in formation on Monsanto capabilities. The final section discusses the market for plastic dielectric films. References and attachments are included for anyone interested in looking into any of these areas in more depth. HIGH TEMPERATURE DIELECTRIC MATERIALS An excellent report on high temperature materials was prepared for the Textiles Division in 19bd by Smithy Stanley & Company,--Incr; The Table on the next page Is from tnis report and forecasts U.S. consumption of high temperature insulation. The report discusses the rapidly increasing use of these materials in: Wire and cable. Motors and generators. Transformers, . Switch gears, and Flexible printers circuits. Hundreds of new polymers, both high temperature and ... othe^ types, are discussed in a rep'0Ttr~0H_4,-New Polymers11 by Skei^t~Laboratories, 1969. The next table is~from that report and~es timat e!T~sal es to the electrical/ electronic industries for the more important new polymers. The electrical industry is projected to grow at about 7/ annually. Consmpjtion-o-high-4;emperature ...electrical InsulatioiL is projected to grow, at a higher rate of ' 'Approximately 11/. . DSW 200303 STLCOPCB4058367 II-3. Table II-1 Current and Forecast U.S. Consumption of High Temperature Electrical Insulation 1967, 1972 and 1977 1967 Pounds 1972 % Incr. Pounds 1967-1972 1977 % Incr. Pounds 1972-1977 Asbestos Ceramics Diallyl Phthalate Epoxy Resin FEP Polymer Glass Fiber Melamine Resin Mica Phenolic Resin (a) Polyamide, Aromatic Polyamide-Imide Polychlorotrifluoroethylene Polyester-Imide f' Polyester, Thermoplastic /Polyester, Thermosetting . \Polyimide Polyurethane, Modified (a) Polyvinyl Formal, Modified (a) Silicone Resin and Rubber TFE Polymer New Products After 1967 3, 733, 000 5,138, 000 8, 520, 000 12, 385,000 13, 500 16,500 551, 000 1, 088, 000 1,113, 000 1, 365, 000 5,563,000 10, 353, 000 135, 000 273, 000 795, 000 1, 654, 000 42,300 51,500 687,000 3,459,000 665,000 1,229,000 ........... 180........ 1,800 189.000 428.000 23, 708, 000 43,209,000 4,984,000 9, 686, 000 1, 380, 000 4. 069. 000 1,935, 000 . 3,156,000 89,000 80, 000 3,445,000 5, 519,000 4, 109,000 5, 078, 000 - 629,000 37.5 45. 22. 97. 23. 86. 102. 108. 21.5 402. 85. 900. ..... 126. 82. 94. 195. 63. -10. 60. 23.5 - 6,401,000 25. 16,430, 000 33. 20, 000 1,206, 000 2, 498, 000 21. u. (83) 14, 333, 000 38.5 404, 000 48. 2,276,000 37.5 63, 000 22.5 6.287.000 ( 2, 870, 000 3, 600 Clcxd 1. 000, 000 59,131,000 Sb 14,716, 000 52. 9.265. 000 (12b 2, 806, 000 -11. 120, 000 50. 7, 561, 000 37. 6, 631, 000 31. 4,158, 00CT' 564. Totals 61, 656,980 108, 867, 800 76. 158,179, 600 45. (a) Only that associated with high-temperature insulation products DSW 200304 STLCOPCB4058368 -4- ELECTRICAL AND ELECTRONICS 4 Methyl Pentene 1 1967 MM lbs. MM $ 1972 MM lbs. MM $ 0.1 0.1 Comments Amplifier, relay housings, electron ic parts. Polybutene 1 D - 0.5 0.1 Wire coating. Chlorinated Polyethylene Thermoplastic Elastomers 1 1 0.3 4 0.3 3 1.0 0.8 Wire and cable. II .^11 . Polyphenylene Oxide 1.4 1.1 10. 6.0 Radio, TV compo nents, HF insula tion, etc. Nylon 12 D . P> 0.2 0.2 Wire enamels, coil bobbins. Fluoropolymers 2.5 12.8 4 23 Insulation and wire enamels. Triazine Polymers 2.5 3.8 5 7.5 Wire enamels Polyxylylenes Small - 0.04 6 . Capacitors S-containing Polymers ( Pe>LY^ut~ 0.9 0.9 6.5 4.5 HF cable, connec tors, circuit breakers, high in tensity lamps. Trans Polyolefins Thermoplastic Polyesters D . a* 0.1 0.4 0.3 . Battery separators 0.4 Wire and cable in sulators, relays, coil bobbins.. EPDM Aromatic Polyamides Polyimides 2 0.6 10 0.8 3.5 2.0 0.6 10.0 1.7 2.5 7 20.0 Wire and cable. Film, wire enamels and varnishes. Polyesterimides Polyamide Imides 0.8 1.2 3.5 0.2 0.5 .8 2.5 Wire enamels and varnishes. ^ 2.0 II II Totals (rounded) 14 35 50 85 B- 24 SKEIST LABORATORIES, INC, L DSW 200305 STLCOPCB4058369 u -5- AROMATIC POLYAMIDES . More than 10 years ago, Dupont developed and obtained rather broad patent coverage on a new family of materials called aromatic polyamides. Since then, markets have been developed for "Nomex" fiber, the product Dupont commercialized in electrical insulation, fire resistant fabrics and other areas. More than half of all Nomex is presently sold to the electrical industry, in the'Torm of an lnsulating~paper. Dupont ' recently constructed' a i^~M pound Nomex plant which is approximately 5C$ sold outf^oj . Demand for Nomex is increasing, especially as an insulation for dry transformers, and the industry would like to have asecond supplier of high temperature paper. Partly for these-reasons^ the Textiles Division developed a competitive aromatic polyamide paper during the middle 1960's, called X-101... It was the develop ment of X-101 which precipitated the $25,000 electrical industry market study by Smith, Stanley & Company, mentioned above. A number of problems caused the Textiles Division to decide not to market X-101, and apparently this decision was influenced by top corporate personnel. Nomex paper is a high temperature (i.e., operates above 200C) material which is considerably less expensive ($3-$4/pound) than polyimide film ($15-$25/pound). Apparently, because of film fabricating difficulties, Dupont decided, to market the material as a paper rather , than as a film." `Uomex is gradually replacing" asbestos afid mica papers in many-appTrca/tions. K----- ------------ ' ~ --------------- ' The following reasons prevented the Textiles Division from marketing this product, First, there are some conflicts between X-101 and certain Dupont patents, although the X-101 patents wouIcTprobably hold'up. Second,_the material would probably have to be made ^ ino a paper, which would mean we would have to go 7 '? into the paper making^buslTiess. This would require a 2 hi_gh 1 nyfetertr Tne Textiles Division was unable to locate a paper compan^-which would produce this paper for a-reusohable price. In addition, there are certain -special technical problems in making papers.of these materials which can be solved, but which come under present Dupont patents. Finally, the Organic Division looked unfavnrahl y npnn t-.hp pa^topf.lnn of mw materials for this product. These would have been costly to produce in relatively low volumes. DSW 200306 STLCOPCB4058370 -6- The laboratories at Durham experimented with making .films from some of these materials, with limited success. I will be in Durham this week to discuss the situation with them. . POLYIMIDES The present annual market for polyimides is approxi mately 1 M pounds, at an average of $15/pound, or $15 M. Page 362 of the attachment from the Skeist Laboratories' report indicates that approximately $10 M of this is in film, and $4 M in wire enamel and varnishes, with the rest in miscellaneous applications. Dupont is also the leader in this field, and is ^realizing most of the sales uT polyimide.products. Present Monsanto sales are approximately $500 M per year in spite of the fact that we have been selling polyimides for 3 years. There are 2 basic processes for producing polyimides. The Dupont process uses polyamic acid. The Monsanto process consists of a reaction of selected alcohols with benzophenone tetracarboxylic dianhydride. The product of this reaction is reacted with selected aromatic amines to produce the polyimide. Normally, the two products are shipped to the user who reacts them in place. The high prices for polyimides result from the high cost of the raw materials required to produce them. Monsanto does not participate in the film market because we do not produce thin films, 3M Company has extensive film knowhow, and has obtained a license frdnTDupont to produce polyimide (Kapton) filfin--very small quantities of Kaptoirtfilm is being rused presently in capacitors. Most of this is being used, in specialty capacitors by the Military. It is estimated by Skeist Laboratories that by 1972, con . sumption of polyimide films in capacitors may be as high as 0.2 M pounds, or about $3 M. Apparently Dupont1s product can be used to more economically apply enamels and varnishes to wire an<T~sheet. Thus, they control tnis"end~-use. Apparently`Monsanto has a better product for use in impregnating fabrics, in molding powder, in grinding wheels, and in foam. The PP&R Division is DSW 200307 STLCOPCB4058371 -7- Kpursuing each of these applications, but unfortunately 1 they are Small in comparison to the two end uses in Vwhich Dupont excells. Our Aviation/Aerospace Group may be interested to know that the PP&R Division is working with the producers of the SST. Appaj^nbiy_-MonsantoJ-S--p^lyimidG foams will be used as insulating and structural supports in, the wings of~the SSTi--According "t'o^Dr. Bob Schatz, Monsanto1 s polylmide foams are the strongest foams structurally available today, bar none. Unfortunately, they are expensive, at $50/pound for foam-in-place powders. The PP&R Division is progressing slowly with research on less expensive polyimide materials. They call these their "poor boy" polymers or Novimides. Regardless of the success of this program, the PP&R Division is set up to market these materials in a1 I^ighiTicant~iapp-li- c at ions except as films'; which woulcTprobably be the" largest" application for the materials! ' ' POLYAMIDE - IMIDES The attached section from the Skeist Laboratories report also discusses polyamide-imides. Approximately $1 M of these materials are being sold today by a half dozen companies. These are high temperature materials which operate at lower temperatures than Nomex and polyimides, but at much lower prices (approximately $2.50/pound). They are sold in films and in other forms. rThe PP&R Division has developed the capability to produce this type of material, but has chosen not to because of the number of other competitors in the field. Apparently our material is_no better than anyone else's^ and again, we do~no^~produce films. POLYCARBONATES AND POLYSULFONES To my knowledge, Monsanto does not produce or have technology for the production of polycarbonates or polysulfones. GE developed polycarbonates and holds most of the patents in this area. Union Carbide is presently the only producer of polysulfones In .the DSW 200308 STLCOPCB4058372 -8- country. Both of these are higher temperature materials than polyesters, but lower temperature than polyamides and polyimides. Polycarbonates are valuable for their high impact strength, transparency, and excellent creep re sistance. Approximately 10 M pounds are consumed annually in electronic and electrical products. Most of this goes into transparent lighting globes. In 1967, approximately 0.4 M pounds of polycarbonate capacitor film (including metallized) was consumed, worth $4-$6 M. This quantity is expected to double by 1972. Polysulfones have slightly better temperature pro perties and slightly better creep resistance than polycarbonates. They are lower in price than poly carbonates, and apparently slightly more difficult to fabricate. 19*67 sale_s to the electrical industry was estimated to be 0.9 M pound_s at $0.9 M. 1972 sales are estimated to be 6.5 M pounds at $4.5 M. Primary electrical uses are as electronic connectors, circuit breaker parts, timer housings, alkaline battery cases, and film for flexible printed circuits. Gfift&ral--Electric has been stated to be working on polysulfone films for capacitors, but this has not yet been confirmed. ------ If we were in the electrical film business, we should be able to market polycarbonate and poly sulfone films, if high purity polymers were available in Monsanto. ' ELECTRICAL PLASTIC FILM Electrical plastic films range in thickness from about 0.1 mil for some capacitor films to about 10 mils. Pages 238-252 of the "Insulation/Directory Encyclopedia" discusses non-supported films and tapes. The table of contents to this directory is attached. The following two paragraphs from Page 239 comment on the present status of plastic films. DS\N 20309 STLCOPCB4058373 -9- "The most extensive applications of plastic firnTs~vgthih the electrical category are in wirg~and cabled fractional horsepower^motors, capacitors, transformers, and coiliT! In t-he-wiT~e~arid~'cable field, thinner films ' wilnr greater strength are replacing bulky cable binder tapes. Flat flexible cable is... being made with conductors sandwiched between two films. Thin-wall tubing is being produced from spiral-wound film for insulating capacitors, resistors, and relays. "Metallized polyester, polycarbonate, ..and ' fluorocarbon film is replacing mica and paper in capacitor technology. Other uses include slot insulation in motors, layer and barrier insulation in transformers, and battery cell separators." At the present time, approximately $PQ M~ nf plastic films are consumed in the world capacitor industry. -Tbtal. consumption of all tnin rilms in tne electrical industry is probably well over $150 M. The table on the--nexf-page lists 'the more' important plastic film materials along with very rough estimates of world consumption of some of these materials in 1967 and 1972. Dupont and 3M Company are by fhr the two largest domestic marketers of films to the eleolrical-industry. Other domestic companies suen as ueneral Eleclrio, " Cellanese, Hercules, and National Varnish, sell lessor quantities of selected filmsT ' YIt appears to me that this is a business which Monsanto should be in. We have extensive polymer technology throughout the company to develop new polymers for films; we presently produce a number of the raw materials such as polyethylene terephthalate which make up the larger volume ^products, and we have men scattered throughout the. company who have some experience with films and film making. The PP&R Division has considered going into this business in . the past and has turned it down for the following reasons. This business is relatively small by their _ standards (sales might be expected to be $10 M - $20 M in 3-5 years); it requires extensive marketing, research, and technical service effort; Monsanto has no centralized location which is knowledgeable in the many facets of thin film manufacture; polymers of high purity are re quired for electrical films; and it is probable that one would have to jump into this industry feet first DSW 200310 STLCOPCB4058374 -10- ESTIMATED WORLD CONSUMPTION OP THIN PLASTIC FILMS IN THE ELECTRICAL INDUSTRY In Capacitors Polyester (Mylar, Polycarbonate Polyimides Polypropylene Sub-Total etc.) 1967 1972 M LB. $ M M LB. $ M 3 64 7 0.4 5 1 8 - - 0.1 2 - - 10 15 3 11 15 32 Unknown Quantity (In Capacitors) Polystyrene Cellulose Acetate Teflon Irridiated Polyethylene Non-Capacitor Usage Polyester (Mylar) Polyimides Polyamide-imide Sub-Total 24 0.2 - .24 45* 7 - .52 32 0.6 0.1 33 52 11 2 55" Unknovm Quantity All films listed as used in.capacitors plus normal polyethylene, other fluorine compounds, PVC and polysulfones. *An equivalent quantity of polyester film goes into flexible laminates for printed circuits. OSVM 200311 STLCOPCB4058375 -11- with millions of dollars of investment to make a go of it. One probably would have to plan to go into the "thin electrical film business" and sell 3 or 4 products, not just to.sell 1 film product, unless it was of very high volume. . There are reasons why it makes sense for the Functional Fluids Business Group to consider this business; 1. We already serve the capacitor and transformer industries where large volumes of films are consumed, 2. It is a special products industry requiring extensive marketing, technical service and research backup -- we are one of the few groups in Monsanto inclined toward this type of operation, 3. We may have to be working with films anyway in evaluating new fluids for capacitors, and 4. This would serve as a launching platform to go into other types of insulation materials, such as metallized films, tapes, etc. Some disadvantages of our Group undertaking such a venture would be; 1. Historically, the H&P, PP&R, and Packaging Divisions have produced films, . 2. Most polymer knowhow is in other Divisions, and historically there seems to have been a reluctance ` ' of Divisions to cooperate to any major extent, 3. Nowhere in Monsanto, and especially in our Group, do we have extensive thin film manufacturing capabilities, ,. 4. Dupont and 3M are tough competitors, 5. We are not at this time serving many of the markets for thin films (but if we are going to expand our efforts in the dielectric area we must take this jump sometime), and 6. This effort would probably require a much larger initial investment than the Functional Fluids Business Group could carry itself without help . from the Division or D Building. DSW 200312 STLCOPCB4058376 -12- I would appreciate guidance as to whether we should approach other Divisions - concerning the possibility of our Group producing and marketing dielectric films. ms Attachments L> MICHAEL F. BABER DSW 200313 STLCOPCB4058377 REFERENCES* 1. New Polymers (a multi-client study) Skeist Laboratories 1969 ' 2. Market Potentials for High Thermal Electrical Insulation Smith, Stanley & Company for the Textiles Division (F. J. Horn) 1968 3. High Temperature Resistant Materials PP&R Report No. 0012 D. W. Dubbell 1967 4. Epoxy Resins PP&R Report D. W. Dubbell 1966 5. Markets for High Performance Organic Fibers Textiles Division (F. J. Horn) 1966 - 6. Analysis of the Asbestos Textile and Specialty Paper Market Arthur D. Little, Inc. for the Textiles Division 1967 Available from Information Center through the Marketing Reports Index. DSW 200314 STLCOPCB4058378 ATTACHMENTS Attached to this memo are: 1. The table of contents to the latest Insulation Directory/Encyclopedia. This classifies the many types of electrical insulation. 2. Pages C-36l to C-382 of the Skeist Laboratories report on "Polyimides, Polyamide-imides, Polyester- imides'1. . DsW 200315 STLCOPCB4058379 Insulation Directory/Encyclopedia Issue For the Electrical and Electronic Industries Lake Publishing Corporation, 700 Peterson Road, Libertyvilla, Illinois 60048, June/July 1969 Publishers of Insulation, Insulation Dircclory/Encyclopcdia Issue, Plastics Design & Processing* * * 4 * 6 Page _.Title; _ 1 How to Use the Insulation Directory/Encyclopedia Issue 4 PART 1--GENERAL INFORMATION 4 Section 1-1: Unit Prefixes, Abbreviations, and Symbols 6 Section 1-2:. Equivalents, Constants, and Conversion Tables 13 Section 1-3: Glossary, Definitions, Formulas 20 Section 1-4: Technical Societies and Trade Associations 21 Section 1-5: Insulation Concepts and Functions 26 PART 2--APPLICATION INFORMATION ' 26 Section 2-1: Insulation in Electronic Components, Assemblies, and Equipment 40 Section 2-2: Insulation in Transformers 46 Section 2-3: Insulation in Switchgear and Control Apparatus 52 Section 2-4: Insulation in Rotating Equipment - 58 PART 3--PRODUCT INFORMATION 58 Section 3-1: Gaseous Dielectrics ' ' 62 Section 3-2: Liquid Dielectrics '- 71 Section 3-3: Fibrous Products: Fibers; Yarns; Cords; Twines; Lacing Tapes; and Untreated Felts, Mats, Woven Tapes, and Fabrics ' 85 Section 3-4: Treated and Untreated Papers and Boards D sW 200316 100 Section 3-5: Treated and Untreated Vulcanized Fibre and Fishpaper 106 Section 3-6: Flexible Tubings, Slcevings, and Ileat Shrinkable Special Devices 127 Section 3-7: Flexible Coated or Treated, Cured or Semi-Cured (Preprcgs), Cloth, Felt, Mat, and Unidirectional Yarn Tapes and Sheeting (Not Self-Adhering) _ 139 Section 3-8: Flexible Cloth, Film, Fiber, Mat, Metal, and Paper Composites L - ? Insulation Diroctorv/Fnevr.lonedin Issue. June/Julv, 1969 STLCOPCB4058380 Page Title 147 Section 3-9: Pressure Sensitive, Adhesive, and Self-Adhering Tcpcs and Splicing Compounds 163 Section 3-10: Plastic Mcterials for Molding and Extrusion: Including Plastic Resins and Compounds; Plasti cizers, Fillers, Reinforcements, Stabilizers, Etc. ' 199 Section 3-11: Rubbers and Elastomer Materials and Compounds t 208 Section 3-12: Varnishes, Compounds, Shellacs, Dispersions, Enamels, Pastes, Waxes, Adhesives, Rubbers, and Powders for Coating, Impregnating, Embedding, Encapsulating, Potting, Casting, and Cementing . \t 238 Section 3-13: Non-Supported Flexible Plastic and Rubber or Elastomer Films, Tapes, or Sheetings (Not Self Adhering) 253 Section 3-14: Reinforced and Laminated Plastic Sheets, Tubes, and Rods; Copper-Clad and Unclad; Plain and Composite .- 277 Section 3-15: Mica Products ' ; 294 Section 3-16: Ceramic and Glass Products ...... 311 Section 3-17: Printed and Molded Circuits; Integrated Microcircuits 322 Section 3-18: Magnet Wire, Strip, Hollow Conductors, and Superconductors . 348 Section 3-19: Wire, Cable, and Assemblies (Except Magnet Wire) 374 Section 3-20: Testing and Measuring Instruments, Equipment, Methods, and Services 401 Section 3-21: Production and Processing Equipment and Accessories ' 421 Section 3-22: Metallic, Magnetic, Shelding, Conducting, and Soldering Materials, Parts, and Supplies 435 Section 3-23: Fabricated, Molded, Extruded, Converted, Processed, and Miscellaneous Parts and Products 450 PART 4--DIRECTORY LISTINGS 450 Section 4-1: Alphabetical Listing of Manufacturers, Converters, Fabricators, and Testing or Research Companies 458 Section 4-2: Geographical Listing of Distributors and Agents 469 Section 4-3: Alphabetical Listing of Trademark Names DSW 200317 478 ADVERTISERS' INDEX 480 481 FREE INFORMATION SERVICE 'X READER SERVICE CARDS AND ORDER FORM FOR EXTRA COPIES OF THE INSULATION CIRECTORY/tNCYCLOPEDIA Cover photos courtesy International Business Machines Corp., Union Carbide Corn., E. ]. du Pont dc Rumours ii Co., and Westinghuusc Electric Corp. Editor und Publisher: Lincoln R. Samc'son Associate Editors: Jon Payne anti Richard Kemmcr Assistant Editors: K. J. Rhodes and O. M. Borders Assistant to the Publisher: 1?. P. .Mignin Contributing Editors: .Sec individual sections. . Art Direr tor: Randall K. Ruth Subscriptions: insulation subscription rales within the U.S. and IJ.S. Possessions are SI.75 tier copy (or a 1 issues other than tin; Insulation Directory/hut yi lopcdia Lstie (which is priced at $13.00 Per copy), $20.00 per year, and $.10.00 for two years. I'nicign sub scriptions are $35.1,0 per year and Pr5.(!0 for two years. Cin ulation rcipiests and iintuirics should give title or department. company name, and products or services of company. Copyright, 1909, by Lake Publishing Corp. Reproduction of text and illustrations not permitted without permission of copyright owners. Opinions expressed in this publication by aulhors arc not neces sarily those of tile publishers and this publication can accept no responsibility in connection wilh any liability which might de velop as a result of ulticks published. insulation, June/July, 1969. Volume 15, Number f>. Published monthly except twice n i.mnih in June, by Lake Publishing Corp.. Box 270, 700 Peterson Road, Libcrlyville, 111. 60013. Phone 312/ 302-5711. - Accept'.*! as controlled circulation publication at Fonliac, III. Advertising Sales Offices: See Paee 481. " .1----rs:,,.. / r nrvrlnncrtia Isr.UG. Junc/July, 1569 3 STLCOPCB4058381 POLYIMID ES, POLYA MID E~I MID ES, POLYESTER-IMIPES ..... ' The polyimides (PI), polyamidc-imides (PAI) and polyester-imidcs (PEI) are higli-temperaturc polymers introduced in the 1960's, Military and aero space markets account for a major share of their production, but several industrial electrical applications will become important. The Pi's, intro duced by DuPont, are used in wire coating, film, molded parts, fibrous binders, and adhesives, while the PAI and PEI polymers are specified mainly for electrical wire enamels and varnishes, The Pi's can be characterized as follows: ; 1, Cost is very high, volume small (dollar sales per pound high), 2, High performance, high temperature electrical markets are the major outlet; the aircraft industry (SST-type craft) and industrial elec-, trical applications (e.g, motors) will strongly influence the rate of future growth, 3, Considerable equipment technology is required in fabricating film and molded products, 4, DuPont is clearly the leader in PI technology and products, but others (e.g, Monsanto) have developed good PI polymers (from different raw materials) that will compete effectively in some markets now dominated by. DuPont, 5, DuPont's marketing philosophy has been to sell semi- or finished products (film, molded parts, pre-preg, wire enamels). They do not sell PI polymer intermediates. Other new entrants have favored selling PI resin " systems directly to fabricators. The PAI polymers are produced only by Amoco at the present time. They have lower temperature properties than Pi's, but offer processing and cost advantages compared to Pi's for certain wire-coating applications. The recent slash in price of trimellitic anhydride (TMA), a PAI building block, to 250/lb. further improves PAI economics. The PEl's are produced by GE, Schenectady Chemical and Westinghouse in the U.S, They have properties intermediate between the polyesters and the PAI and PI for wire coatings, their single end use. They are more expensive than the polyesters but cheaper than PAI or PI. Consumption of polyimides was an estimated 0.7 million, pounds in 1967;- worth $10-12 million, and close to 1 million pounds in 1968. By 1972, con sumption will grow to 2.5 million pounds, valued at nearly $23-26 million. The polyamide-imides, which are used almost exclusively in wire coating, had a volume of 150,000 pounds in 1967 (nearly $0.5 million) and close to 300,000 pounds in 1968. Good growth is projected, with volume reaching slightly under 1 million pounds by 1972. Polyester-imides, which are con sidered here only in wire coating, have an excellent price/property balance that will enable volume to move from 0,8 million pounds in 1967 to 3.5 million pounds by 1972. " C-361 SKE1ST LABORATORIES; IHC. DSW 200318 STLCOPCB4058382 TABLE 1. ESTIMATED CONSUMPTION - POLYIMIDES, POLYAMIDE-IMIDES, POLYESTER-IMIDES, 1967-1972 (MM lbs.) 1967 1972 Application M lbs. MM $ M lbs. MM $ Film PI PAI, other Subtotal Wire Enamel^and Varnishes PI PAI PEI Subtotal Molded Parts, Shapes 2f) 225 225 7.0 750 50 800 14.5 350 150 800 1300 3.0 0.5 1.2 4.7 900 800 3500 5200 5.5 2.0 2.5 10.0 PI PAI Subtotal 50 ) see 350 dev.j 2)below 50 50 400 4-8 Adhesives and Binders for Reinforced Plastics 3) PI PAI, other 75 neg. 75 0.5 neg. 0.5 500 75 575 4-6 Other dev. - <100 0.5 Totals: PI PAI PEI . 700 150 800 2500 975 3500 Grand Total (rounded) 1700 13 7000 37 1) Values show pounds used as solids and estimated dollar value of each pound used. Value of gallons sold based on solids used would be higher, 2) The 50,000 pounds shown are almost all fabricated Vespel parts made by DuPont, Since most of these are custom made, dollar values are impossible to assign, A guesstimate for 1967 would be $2-3 million. Figures in 1972 for PI include 225,000 lbs, of Vespel, and 75,000 lbs, of Cyanamid-type molding resins, 3) Includes solutions for impregnating and prepared prepregs. DSW 200319 c-362 SKEIST LABORATORIES, IKC. STLCOPCB4058383 TABLE 2. WORLD SUPPLIERS OF COMMERCIAL PI, PAI, PEI PRODUCTS (By Application) Form Polymer Tradename Supplier Varnish, enamel (wire & cable) Polyimide tt II Polyamide-imide Pyre M.L, Quaatad 159 AI It Polyester-imide u it it tt tt it Omega , Imidex E, I Isomid Tereboc FH, FN; Allebec IC 521 Celiatherm S E 3520 Polybenzimidazo- Tharmotite (in dev.) pyrrolidone DuPont 3M (license) Quantum Amoco (Anaconda, Sterling Varnish) Westinghouse (dev.) Westinghouse' GE Schenectady Chemical Dr. Beck & Co.(Ger.) Lackfabrik Celia (Ger.) Kurt Herberts (Ger.) Showa Elec. Wire & Cable (Japan) Molded products Polyimide Vespel 11 Meldin " molding powder XD-182 Polyamide-imide AI " M-33 DuPont Dixon ' Amer. Cyanamid (dev.) Amoco (dev.) Rhone Poulenc (Fr.) Film Polyimide it tt Polyamidc-imide Kapton dev. dev. Amanin DuPont Raychem 3M (license) Westinghouse (sold to Rogers Corp.) Adhesive Polyimide ii Benzimidazoleimide FM-34 Ketalbond 1-40, I-6i Amer. Cyanamid Narmco Westinghouse Binder-Rein- Polyimide Skybond 700 series forced plastic " ii PI 2501, 3301 P 13 N ii tt ModiTied PI RS-5303, 5 ii Quantad 159 Polyamide-imide TR 150-2 T Polybenzimidazol e Imidite Monsanto DuPont ' TRW Brunswick Corp. Shawinigan Resins' Quantum,Inc. Thermo-Resist Narmco DSW 200320 C-363 SKE1ST LABORATORIES, INC. STLCOPCB4058384 TECHNOLOGY Commercial polyimides are made by reacting tetra acids or dianhydrides (e.g. PMDA, BTDA) with diamines (e.g. benzidine or oxydianiline). A simplified version of the acid-amine relationship in synthesizing high-performance resins is shown below (a combination of 2, 3 or 4 acid and 2 or 4 amine). ' Acid Amine Some of the dianhydrides which are commercial or developmentally used include: T. Pyromellitic dianhydride (PMDA) ' 2. 3,3',4,4'~benzophenone tetracarboxylic acid dianhydride (BTDA) 3. 1,4,5,8-naphthalene tetracarboxylic acid dianhydride (NTDA) 4. 1,2,3,4-cyclopentane tetracarboxylic acid dianhydride (CPDA),,.,,. Diamines most commonly used include: 1. 1,3-diaminobenzene(m-phenylene diamine) (MPD) 2. 4,4'-diaminodiphenyl ether (oxydianiline) (ODA) 3. 4,4'-diaminobiphenyl (benzidine) 4. 4,4'-diaminodiphenyl methane (methylene dianiline)(MDA) Solvents of importance include: 1. Dimethyl formamide (DMF) 2. Dimethyl acetamide (DMAC) 3. N-Methylpyrrolidinone (NMP) 4. Dimethyl sulfoxide (DMSO) Polyimides The commercial Pi's supplied by DuPont are the reaction products of PMDA with a diamine such as oxydianiline, while those supplied by Monsanto may be based on BTDA (or a proprietary compound) and oxydianiline or methylene dianiline, ; SW 200321 C-364 SKEIST LABORATORIES, IRC. STLCOPCB4058385 FMDA 4,4-Oxydianiline yco-fr^-^\ +HJ.-- -1>" TM2 soluble prepolymer (polyamic acid) --4 -HN-CO^0^CO-NH^g)-O-(g)-- * HOOCsXCOOH insoluble thermally stable PI -) " "N, With BIDA, the end product would be: Jn rCjgrC> -0 0 -* n Several other routes to polyimides are noted in this section based on variations of the dianhydride and/or diamine. For example, Narmco has studied poly(m-phenylenepyromellitimide), the polyimide from ODA and BIDA, whose formula is shown above, and others. . Ideally, the reaction between dianhydride and diamine takes place in two steps. First, a polyamic acid is formed which is soluble in selected highly polar solvents to the extent of 10 to 40%, Such solutions can be used in wire enamels and other coatings. After application and evapora tion of the solvent, condensation to the polyimide takes place at elevated temperatures. . OC >X OC Lr X iCO X + -----OC-^ yCO-NH H2NR*NH2--^ N CtX . H00C , NH' C00H ""2 dianhydride diamine L_ polyamic acid 0 .C. R. . XN-R-N< X .0 0 polyimide + h2o DSW 200322 The water of condensation is not a problem in the making of thin films or coatings, but thicker articles must be fabricated under pressure. C-365 SKEIST LABORATORIES, IKC. STLCOPCB4058386 The fully reacted polyimide is insoluble and infusible, presumably because of side reactions which result in crosslinking. Polyamide-Imide Trimellitic anhydride (IMA) reacts with diamines to yield amide-imide polymers such as Amoco's AX polymer (Type 10) p 8-OH 1| r 0 1-0-h-U-5-r4 --> -1 n U 0 N-R-*1 n ortho amic form cured or imidized form Westinghouse Electric (U.S, Pat. 3,179,635) investigated a wide range of copolymers having various proportions of amide-imide groups. These materials, while lower than the Pi's in heat resistance, offered better ; solvent solubility and improved mold flow. Polyester-Imides These polymers are made by reaction of TMA or other anhydrides with both aromatic diamines and polyalcohols, to obtain a variety of structures. i i They are used for magnet wire and other coatings. PEI patents refer to the use of terephthalic acid, phthalic anhydride, trimellitic anhydride, ethylene glycol, glycerine and methylene dianiline in PEI synthesis. For example, the ethylene glycol forms a linkage between the two TMA molecules; when reacted with a diamine, it reacts preferentially with the anhydride group, resulting in a dicarboxylic acid, which can then be reacted with glycerine. One diester dianhydride cited in patents is . synthesized from TMA and dimethyl ester as follows: . f) 0^ \ (l-O-Ar-O-C-CIIj--^ + CH, COOH -C-O-Ar--0-C1 ii i 00 ft --c. + 2CH^C00H This dianhydride can then be reacted with diamines. The triester anhydrides of trimethylolethane and tetraester anhydride of pentaerythritol permit crosslinking, which is desirable. DSW 200323 C-366 SKEIST LABORATORIES, INC. i i i i i i !i i t i ilI STLCOPCB4058387 PATENTS DuPont disclosed the chemistry of making linear fiber-forming polyimides in British Patent 570,858 (1945) and subsequently in U.S. 2,710,853 (1955). Since then, DuPont has been granted about 40 patents on various intermediates., methods of polymerization, and PI products. TABLE 3. SELECTED PATENTS ISSUED TO DU PONT AND OTHERS Patent # Year Comment A. DuPont: U.S. 2,710,853 2,712,543 2,731,447 2,811,548 2,867,609 2,880,230 2,900,369 3,073,784,5 3,179,614 3,179,630-34 3,336,258 3,356,759 3,356,648 3,342,897 3,342,774 3,299,101 3,361,586 3,376,260 1955 1955 1956 1957 1959 1959 1959 1963 1965 1965 1967 1967 1967 1967 1967 1967 1968 1968 Polyimides of pyromellitic acid Polyimide intermediates Novel polyimides Purifying aromatic dicarboxylic acids Preparation of HMW polypyromellitimides Related to 2,710,853 Polyimide composition Electrically conductive PI " Polyimide-acids, compositions and preparat: Preparation of polyimides Crosslinked polyimides Polypyromellitimide compositions Hexafluoropropylide polyimides Unique polyimides Polyimide preparation PI Treating polyimide surfaces Aromatic polyimides Brit. 570,858 898,651 903,271,2 945,673 1945 1962 1962 1964 Linear fiber-forming polymers Polyimide polymers II Polyimide films Belg. 614,941 627,623 627,625 627,629 630,749 535,549 638,688,9 649,336 . Neth. 6,504,004 Appl. 6,512,677 1962 1963 1963 1963 1963 1964 1963 1964 Polyamic acids Polyimides Powdered polyimides Moldable polyimides Carbon-filled polyimides Coating compositions Expanded polyimides Polyimides 1964 Polyimide filaments 1966 Polyimide adhesives ' B. Other Firms; 1. U.S,Patents Company . ' 3,037,966 Union Carbide 1963 Thermoplastic polyimides 3,105,775 Shawinigan Res.1965 Polyimide wire coatings DSW 200324 C-367 ' SKE 1ST LABORATORIES, -3HC. STLCOPCB4058388 TABLE 3 (continued) 1. U.S, Patents 3,190,856 3,260,690 3,347,808 3,152,073,4 3,179,635 Company Monsanto II It <3.E. Westinghouse Year 1965 1966 1967 1965 1965 Comment High solids, low viscosity polyimides Polyester imides Polyamide-imide ' 2. European Patents Ger.1,111,635 BASF 1961 Ger.1,151,120 Bayer Belg. 666,934 II 1963 1965 Brit.1,084,902 Distillers Brit.1,094,251 tl 1967 1967 Brit.904,559 ICI Brit,1,037,374 II Fr. 1,454,878 It 1962 1967 1966 Brit.935,388 Westinghouse 1963 Fr.1,478,938 Schenectady Ch. 1967 Brit.1,082,181 It 1967 Polycyclic dicarboximides Ion exchange resins Polyimides Polyimide bonding Polyimides Polyamide-imide resins Polyimide fibers Molding polyimides Polyamide-imide Polyester-imides Polyester-imides # SUPPLIERS, MATERIALS, PRICES Raw Materials PMDA (1,2,4,5-benzene tetracarboxylic dianhydride). PMDA is produced commercially by two firms in the U.S. -- DuPont, for captive consumption almost exclusively, and Princeton Chemical Research, "PCR" (Princeton, N.J.), for sale. In the Princeton process, durene (1,2,4,5-tetramethylbenzene) is catalytically oxidized in the vapor phase. A wet process, nitric acid oxidation, is believed used by DuPont. The PCR process is believed to give higher yield and purity at lower cost. PCR's capacity is about 0.4 million pounds, while DuPont's Capacity is in the multi-million pound range. Hexagon Laboratories attempted to make PMDA but withdrew. The degree of future price declines of PMDA will affect the price structure of Pi's. Current prices are $3-4/lb. for substantial quantities on a negotiated contracted basis. DuPont, a reluctant supplier of the dianhydride, has a list price of $5/lb. U.S. sales (i.e. excluding DuPont's usage) was probably under 0.1 MM lbs. in 1968. ; In addition to polyimides, PMDA is used in small volume as an epoxy curing agent, in high-temperature-resistant plasticizers for PVC, and for metal finishing, .' Suppliers of durene from aromatic (BTX) reforming operations include Sinclair and Enjay; Sun Oil and others are potential sources. Durene capacity is about 10 million pounds, and price is 60^/lb. (f.o.b. Sinclair). At sales of 30 million pounds, durene could be about 15$/lb., and PMDA 50^/lb. To reach the low prices of trimellitic anhydride (25<?/lb.) , durene sales would probably have to be 50 million pounds a year; this is unlikely for many years. _ DSW 200325 C-368 SKEIST LABORATORIES, INC. i I II j I i j STLCOPCB4058389 Total merchant demand for PMDA was less than 0.5 million pounds in 1968. PMDA-based Pi's are now receiving stronger competition from TMAbased PAl's and BTDA-based Pi's, hence volume growth of the PMDA-type resins may not be enough to effect a substantial decline in the price of PMDA unless significant new applications are established. Ruhroel Chemiewerke (Bottorp, W. Germany) produces PMDA from durene by a continuous oxidation process. Prices are cheaper than in the U.S. (Some quotes are $2.00-2.50/lb.). However, several potential high-temperature plastic users in the U.S. indicate that purity is not equivalent to U. S, grades, Toyo Kasei Kogyo Ltd. (Japan) makes PMDA for captive uses. BergbauForschung G.m.b.H, (Essen, West Germany) also has PMDA technology based on the chloromethylation of p-xylene. Furukawa Electric Industries Co. (Tokyo, Japan) will be offering a high-purity dianhydride at competitive prices. BTDA (3,3',4,4'~benzophenone tetracarboxylic acid dianhydride). Gulf has been building a 10 million pound plant to produce BTDA. The major outlet is for epoxies. Prices are about $2/lb., but a possible long range decline to the 50$/lb. range has been cited by several respondents. BTDA also has potential in producing pyrrones (e.g, when used with tetramines such as DAB), Available grades are reportedly not pure enough for some grades of polyimides and pyrrones, -TMA (trimellitic anhydride). TMA is produced by Amoco Chemicals (Joliet, 111.). Upon expansion to 50 million pounds capacity late in 1968, they dropped the price from 54<?/lb. to 25$/lb. Consumption of TMA in 1968 is estimated at 7 to 10 million pounds, most of which was used in "non-volatile" PVC plasticizers for auto upholstery and electrical insula tion. The polyamide-imides constitute a small captive and merchant outlet. The projected growth of TMA in plasticizers and consequent cost reduction could allow Amoco to reduce PAI prices from the $3.00 level and encourage others to make PAl's, presumably under license. (See wire coating section for further discussion) Oxydianiline, methvlene-bis-aniline, m-phenylene diamine, DuPont reportedly uses oxydianiline in producing "Pyre ML" and "Kapton". Monsanto also could be employing oxydianiline in their Pi's. Dow and Ott Chemical have been merchant suppliers in the past; DuPont probably makes this chemical captively. Prices have been quoted at $1.90-2,00/lb. Methylene-bis-aniline, which sells for about 56<?/lb., is available from Dow, It may be used by some PI producers. Amoco's AI 10 polyamide-imide reportedly uses m-bis-aniline, while their AI 11 is made from m-phenylene diamine. ' Polymer Intermediates and Finished Products Polyimides. Sincu DuPont introduced PI materials, in the early 1960's, several new entrants have commercialized competitive materials in one or more of the current PI markets. None, however, covers as many application areas as DuPont. The various DuPont PI products are marketed by various divisions already selling other products to the industry, as shown below. DSW 200326 C-369 SKEIST LABORATORIES, INI i STLCOPCB4058390 MARKETING RESPONSIBILITY OF DU PONT PI PRODUCTS Market Department Form Tradename Status ' Electrical film Electrical wire coatings Film Fabrics & Finishes Aircraft/aero Plastics space; industrial Aircraft/aero space It -' Fabrics & Finishes Fibers ? ? Film Liquid enamel & varnish Solid molded plastic Prepreg Kapton Pyre-ML Vespel PI - Foam am Semi- - conductors Commercial (1965) Commercial (1961) Commercial (1965) Serai-commercial . Experimental II II > The manufacture of PI grinding wheels is probably the only venture that does not "fit'* an existing marketing group, A. profile of company activities in PI, PAI, and PEI products follows. SUPPLIERS OF PI, PAI, PEI PRODUCTS United States DuPont, Major factor in PI business -- PI enamels and varnish (Pyre ML, Pyralir.) molded parts, shapes and abrasives (Vespel) ; film (Kapton); binders; adhesives; other products in development, Amoco, Produce polyamide-imides ("AI" series) mainly for magnet wire enamels; also developing laminates, adhesives, coatings, molded parts, Monsanto. Strong in PI coatings and binders for reinforced plastics (Skybond series 700). . American Cyanamid. Developing injection-molding PI grades (XP-182), and structural adhesives (FM-34). 3M. Have PI fabrication patents; entered into licensing agreement with DuPont to produce PI films and coatings, ./ TRW, Commercialized PI laminating varnish in 1968 (P 13 N), ; Raychem, Pilot plant quantities of self-developed PI for film. / Westinghouse. Considerable polyamide-imide, polyester imide and BTDA- based PI technology; PAI film (Amahin) technology reportedly sold. PE* .'Omega'* wire coatings commercialized. . C-370 . SKE1ST LABORATORIES, IHC. DSW 200327 STLCOPCB4058391 United States (continued) General Electric. Iraidex polyester imide wire coatings; film technology. Schenectady Chemical, Isomid polyesterimide wire enamels. Whittaker (Narmco). Developed PBI, PI, aliphatic polyimidazole . ("Imidite") and other high-temperature heterocyclies. Development work centered around the aircraft industry. . Quantum. Polyimide binders and coatings are offered by this small firm. Dixon. Molds PI parts; complements its established position in fluoro carbon parts. "y Europe Rhone Poulenc (France). PI products introduced in 1968. Could be supplier for European supersonic aircraft. Distillers (U.K.). PI patents. ' ~ICI (U.K.). PI technology. BASF (Germany). PI patents. ' Bayer (Germany). PI patents. Dr. Beck (Germany), Polyester imide wire coatings (Terebec, Allebec), Lackfabric Celia (Germany). " " " (Cellatherm S). Kurt Herberts (Germany). " " (E 3520). Japan Tovo Rayon. PI technology. Products may be commercialized in 1969. Showa Electric Wire and Cable. Wire coatings. END USES Film DuPont's "Kapton" polyimide film (called "H film" during its experi mental stage) maintains excellent electrical, mechanical and thermal properties over a wide temperature range (-42 to 752F.), In addition, flexibility is retained at cryogenic temperatures, and the film is flame resistant, infusible and resistant to organic solvents. Cost is high ($20-30/lb.); but this unique balance of properties has been favored in a growing number of high-temperature electrical applications, such as cable wrap, motor and slot liners,'transformers, capacitors, flexible printed 0-371 SKE1ST LABORATORIES, INC. DSW 200328 STLCOPCB4058392 circuits, magnetic and pressure-sensitive tapes, and a few commercial and industrial uses. . Volume has increased from the 45,000-55,000 lb. range in 1965 to ' 100,000 lbs. in 1966, 225,000 lbs. in 1967, and 300,000 lbs. in 1968. By 1972, volume is estimated at 800,000 lbs., of which at least 90% will be Kapton. In 1967, the estimated 225,000 lbs. consumed had a sales value of about $7 million. DuPont is currently the only supplier of high-temperature PI film, but Raychem has been developing both PI intermediates and film as ah addition to their high-performance film line. Westinghouse developed a PAI film, "Amanin", but little has been seen in the field. Kapton film is made by a sophisticated (and expensive) casting process at Circleville, Ohio, the production center for other DuPont films (e.g. Teflon, Mylar)., The film was first offered commercially in 1965,after several years of testing and equipment development. Several firms inter viewed in this study had attempted to cast comparable films, with little: success. The 3M Company reportedly has patents on a PI casting process, and under their 1968 license agreement with DuPont, will become a supplier. Two Kapton film grades are important -- Type H, the original "all PI" film, offered in 0.5 to 5 mil thicknesses, and Type F (1.5 to 6 mils), a composite of Kapton coated on one or both sides with varying thicknesses of Teflon FEP fluorocarbon resin to provide heat sealing. Considerable advances have been made by DuPont in producing thinner films and composites (e.g. Nomex), For example, an H film only 0.5 mil thick can be coated with only 0,5 mil of fluorocarbon. The 1, 2, 3 and 5 mil H film gauges are in greatest demand. Prices for these are $23-25/lb,; thinner gauges (0.5-0.25 mil) are substantially more. The HF composites cost $30/lb. It is doubtful whether prices will decline much, since the military and aerospace markets are concerned about performance rather than competitive pricing. In order to make a worthwhile penetration of the lower cost/performance film market -- e,g. polyesters, now $2 to $3/lb. -- prices would have to be less than $10/lb. By 1975, it is possible that some PI grades will be in this price range because of ' increased volume, lower raw material costs and new competition. However, prices of the lower cost films will decline also, thereby maintaining a sizable differential. Furthermore, DuPont's own. Mylar is the leading poly ester film. The probable price strategy of PI film suppliers will be do. maintain prices near current levels while expanding uses in high-performance, price-inelastic markets. ' Aerospace/military wire and cable wrap and commercial traction motors probably accounted for more than 907. of Kapton film use in 1968. DuPont sells "reliability" in all applications except motor insulation, where economics is an added factor. The insulator most vulnerable to PI film replacement is mica. Within the next ten years, the greatest PI film growth will take place in high-performance motors, where Class H-rated motors are gaining at the expense of lower rated systems. However, redesign of motors to take advantage of their film insulation will probably take five years. C-372 SKE1ST LABORATORIES, INC. DSW 200329 STLCOPCB4058393 Rotating Electrical Equipment. Locomotive traction motors Ims lionn ' the largest l'X film outlet. General Mol nrn XV. I n< I t iwil I li I /1 a I >.n , *.*' Grange, 111.) I: I rut (l|t<u`I I I oil I'l i'll lit In I'Ki'i. 'ilin'i-. limy n i i on n I ml I m over* 607. oi' the OEM locomotive luiaJ.iieaM, tlielr uunge may lm tin: lurgciit in the U.S. General Electric is the other major locomotive producer. 'PI'-LIlm (2 mils) replaced mica tape that was twice as thick in conductor insulation. The thinner PI film allowed more copper and less insulation within the frame and armature design, resulting in greater horsepower at a lower total cost. PI film also is used to a smaller extent in ground insulation (4-5 mils) in place of glass/mica. Type F composites will be the predominant film because ' of better moisture resistance. In addition to OEM (original equipment of manufacturer), increasing film volume is going to the locomotive repair market. Other large motors are likely to switch to PI in the future. About 50,000-70,000 pounds of PI film, worth $1.5-2,0 million, were consumed in traction motors in 1968. Slot liners for high reliability motors and layer insulation in transformers are other applications. Wire and Cable (Classes F and H). FEP-coated PI composites (HF film) are being used as-primary insulation in a number of military wire and cable systems (mainly hookup and harness wire). These include space and launch vehicles, military and civilian aircraft (Mil W 81831 AS), These thin film composites offer weight (507.) and space savings (257.), thermal endur ance and better reliability. On a value analysis basis, their high price ($30/lb.) is not a limiting factor, Kapton film has been used in the TITAN III, SPRINT and LEM vehicles, to name a few. Another missile uses .. 3 oz. of H film and Pyre ML varnish (or about 5,000 to 10,000 lbs, forall eventual units). Several aerospace vehicles have used thin gauge, metallized Type H PI film for cryogenic and high-temperature insulation of storage tanks. Film is applied by several wire and cable suppliers, such as Tensolite (Tarrytown, N.Y.), Brand Rex (Wilmantic, Conn.), Haveg Super/Temp. (Winooski, Vt.), Simplex (Westbury, N.Y.) and others. DuPont offers several composites tailored to meet differing wire and cable systems. Usage has increased from 40,000-50,000 pounds of all PI and composite film in 1966 to an estimated 60,000-80,000 pounds, worth $1.5 to $2.0 million, in 1968. A substantial reduction in the space and military program could signif icantly affect future growth. Printed Circuits. Small volumes of Kapton composites are used in base and cover sheets for flat cable and printed circuits used in aerospace, air frames, and controlled circuitry. The film permits the design of thin structures with good high-temperature dimensional stability, and is resist ant to soldering of copper. Laminates of PI film to copper for etching . printed circuits are available. ; Capacitors. Capacitors insulated with PI film have high insulation resistance over a wide temperature range, and high radiation resistance.. Metallized PI film, consisting of silver, gold and aluminum (on 1 mil of Kapton) are used for specialty aerospace capacitors. Eventually, deposits C"373 SKEIST LABORATORIES, IHC. DSW 200330 STLCOPCB4058394 will be made on 0,25 mil film. It is doubtful whether PI film will be used in growing volume in the commercial capacitor field, since its thermal properties are not required and price is prohibitive. However, prices for specialty capacitor films used by the military are very high (e.g. $40/lb. for thin polycarbonate film) and cost is less of a consideration. One major capacitor user indicated that metallized PI capacitor film was being tested for street lighting requiring higher temperatures (200C. instead of 150C.). Consumption of polycarbonate capacitor (including metallized) films . were 0,4 million pounds in 1967, worth $4-6 million. Of this total, about 0,2 million pounds were used in military applications. By 1972, volume is expected to reach 1 million pounds. Polyester film consumption was 3 million pounds in 1967, and will grow to 4 million pounds by 1972. Polyimides may' capture about 4% of the 1972 usage of 5 million pounds for PC and PET, or 0.2 million pounds. Tubing. About 500 pounds of composite and regular PI film is used in spiral tubing for relays, steering, thermal insulation and related parts. Niemand Bros. (Elmhurst, Long Island) is a major supplier, Pressure-Sensitive Tape. The Permacel Co. (New Brunswick, N.J.) offers a pressure-sensitive tape based on a 1 mil PI film backing, bonded with a pressure-sensitive silicone adhesive. Specification is for applications requiring strength, abrasion resistance and high operating temperatures.'' Magnetic Tape. The U.S. Tape Division of Wabash Magnetics and one or two smaller firms offer a Pi-based .magnetic tape. The thermal endurance of PI provides an advantage over PET or PC films in very high temperature environments. : : Electrical Wire Coating The enamels and insulating materials in this category include those with a thermal rating of 155C. and up -- polyimides, polyamide-imides and polyesterimides. Major users include the following, which accounted for about 80%, of production in 1968: Anaconda (Muskegon, Mich,; Sycamore, 111.); Phelps Dodge (Ft. Wayne, Ind.); General Electric (Ft. Wayne, Ind.); General Cable (New York, N.Y.); Belden (Chicago, 111,); Alcoa-REA (Ft.Wayne, Ind.); Essex Wire (Ft. Wayne, Ind., other sites). Anaconda and Phelps Dodge probably sold at least 50% of the PI and PAI wire coating.systems. In 1967, over 10 million gallons of magnet wire enamel, valued at over $30 million and utilizing more than 20 million pounds of resin solids, were applied to about 550 million pounds of wire valued at about $410 million. Growth is expected to continue at 7-8% annually, reaching 13-15 million gallons by 1972, or 25-30 million pounds of solids. Coated magnet wire (virtually all copper) is used in motors, trans formers, generators, control devices and magnet coils. The resin-based coating contributes insulation, thermal and chemical resistance. End users are requiring ever more demanding performance with regard to winding speeds, temperature and chemical resistance. DSW 200331 C-374 SKEIST LABORATORIES, INC. STLCOPCB4058395 Materials competing in various segments of the high-performance coating field include: Material Supplier Thermal Class,C. Trademark Polyimide Polyamide-imide Polyes terimide DuPont Amoco GE, Schenectady 220 200 180 Pyre ML AI Imidex, ; There is disagreement among end users as to the reliability of the thermal ratings shown above. Some indicated that field performance sug gested 180C. and 155C. for the PAI and PEI1 s ,respectively. Consumption of these materials and competitive wire coating enamels is shown below: . TABLE 4. CONSUMPTION OF WIRE COATING POLYMERS (MM lbs.) ' Material - 1967 1972 Oleoresihous Polyvinyl formal Acrylic, epoxy, other Polyester Polyurethane Polyimide Polyamide-imide Polyester-imide 4.0 2.5 4.5 3.3 4.0 7.5 5.0 9.5 3.5 4.5 0.4 0.9 0.2 .0.8 0.9 3.0 Subtotal: PI, PAI, PEI TOTAL 1.5 22.5 4.7 32.0 Polyimides. DuPont's "Pyre ML" PI liquid enamels and varnishes were commercialized in 1961. Magnet wire enamels used in generators, transformers, heavy duty motors, sealed relays and hermetically sealed refrigeration' systems at continuous temperatures up to 428C. consumed well over 70% of all PI varnishes used in 1968. Other applications included coatings for glass fabrics and insulating varnishes. Consumption of PI has increased from 0.2 million pounds in 1965 to 0.4 million pounds in 1967 and 0.5 million pounds in 1968. Amoco*s PAI systems have started to offer strong competition in several wire coating applications now using PI. Although PI has about a 20C. higher thermal rating, PAI offers several advantages in handling, noted below. Problems of PI include poor abrasion resistance, short shelf life, difficult to strip, lower coating speeds (high boiling point of the solvent) and high scrap losses. Pyre ML was the first enamel to be accorded a 220C. rating. Locomotives . and fractional horsepower motors constitute the major markets. General Motors (Electro Motive Division, La Grange, 111.) is a key specifier of Pl-enameled rectangular wires (also Kapton H film). Fractional horsepower motors (often hermetically sealed) specify PI enamels because of the high C-375 SKEIST LABORATORIES, INC. DSW 200332 STLCOPCB4058396 temperatures that result from continuous use, e.g. in portable tools, overload, and higher armature rotational speeds. The trend toward subminiaturization promises to maintain the demand for the properties offered by Pl-type enamels. The success of PI enamels in small motors has resulted in their spec ification in other motor and generator systems operated at high temperature, e.g. industrial construction equipment and dry power transformers. DuPont produces Pyre ML in Chicago to service the midwestern magnet wire market. Military specifications heavily favor PI systems relative to other '`imide coatings", ; . . Two major grades are offered: Type I, selling for $13-15/gallon ; (15-17% solids) or about $2,00/wet lb, for rectangular wire; Type II (27-30% solids) which sells for $4.00/wet lb. and is used for finer wire. A Type III system reportedly competitive to PAl's in price has been under development. The PI resin value averages about $13/lb. for both types. The high cost of the PI enamels is influenced by the use of expensive solvents (N-methyl pyrrolidone costs over $3.00/gal.). . Polyamide-imides. Amoco1s PAI wire enamel is similar in performance to the Pi's (formulated in a 257. solution of N-methyl pyrrolidone). Its thermal capabilities "on paper" are 20C, lower, but its applied cost is several dollars less. End users cite several advantages over PI -- easier to process (lower softening temperature); better resistance to scraping; better windability; and re-usability of scrap. Originally, it was reported that Anaconda had an exclusive license to use (and license) the AI materials, which they purchased as powder. Recent data indicates that this relationship may have changed, and that Amoco is selling the liquid system to Anaconda, Phelps Dodge and others. Already much cheaper than PI, PAl's long-term economics promise to be even better. The recent price drop of TKA, from 54$/lb. to 25$/lb. is likely to provide greater future price flexibility for the polymer. A near term price for PAI polymer is $2.50/lb. (from $3.00/lb. in 1968), and a $1,50/lb. range is possible if sales reach 15-20 million pounds. About '7-10 million pounds of TMA were used in premium plasticizers in 1968. This could reach 20 million pounds by 1972, and 25-30 million pounds in 1975, resulting in price reductions of TMA to 21q/lb. and 17$/lb, , respectively. But several obstacles must be overcome. In several, for high per formance military and aerospace applications, PI will be preferred despite its higher price. Also, some end users felt that the 200C. thermal rating for PAI should be downgraded to 180C., based on their experience. If true, this would widen the PAI-PI thermal group. Furthermore, some respondents claim that PAI, when used alone as an insulating varnish, has poor chemical compatibility. This may have influenced Anaconda and Phelps Dodge to sell a composite wire consisting of cheaper polyester 807 and 20% PAI topcoat. For the future, neither military nor household (UL) appliances appear to offer increasing outlets for PAI. The industrial field -- non-military motors, process equipment -- may be better opportunities. DSW 200333 C-376 SKEIST LABORATORIES, INC. <* t 1 STLCOPCB4058397 Polyesterimide (PEI). The PEI's may be considered "upgraded" poly esters, with a thermal rating of 180C. They essentially combine polyester and polyimide chemistry, and fill the need evidenced by the relatively poor heat shock resistance and windability of the polyesters and the cost and processing problems of PI wire enamels. They are intermediate in both properties and price between polyesters and PAI. Schenectady Chemicals (Schenectady, N.Y.) has offered Isomid PEI coatings for several years (British Pat. 1,082,181 or Fr. Pat. 1,478,938). In February, 1969, they were scheduled to receive a U.S. patent, which may cover compositions offered by other suppliers. GE (Insulating Materials Division, Schenectady, N.Y.) is a recent entrant with Imidex E enamels (see U.S. Pat. 3,182,073 and 074). Westinghouse offers Omega PEI's, but relatively small consumption was noted by major coaters interviewed. Schenectady and GE account for most of the volume, which was about 0.8 . million pounds (solids) in 1967, and nearly 1 million pounds in 1968. By 1973, volume is expected to grow to 3.5 million pounds, at the expense of several materials noted below. (Some firms in this business forecast 4-5 million pounds by 1972.) Several firms have commercialized PEI in Europe. Dr. Beck & Co, (Hamburg, Germany, acquired by BASF) disclosed PEI technology in the early 1960`s (Brit. Pat, 973,377) and now supplies Terebec FH, FN and , more - recently, Allebec PEI enamels. Other German suppliers include Lackfabrik Celia (Cellatherm S) and Kurt Herberts (E 3520). Only small quantities of. Dr. Beck coatings have been imported into the U.S. (through D. W. Blackburn Co., Dobbs Ferry, N.Y.) as prices are high and expensive technical service is required to meet the differing formulation and equipment needs of each company. Schenectady Chemical, through its French affiliate, has gained^an important share of the European PEI electrical coating market. ' The cost of PEI per "wet pound" is 50<?/lb. (28-35% solids), which is considerably cheaper than PI or PAI coatings. Raw materials are dropping in price. There are several application opportunities for PEI`s, Generally, applications where the thermal properties of PI or PAI are not required but where polyesters are not adequate will be PEI targets. Hermetically sealed systems requiring good chemical resistance will be the largest outlet initially. Segments of the polyvinyl formal (e.g. Formvar) and alkyd elec trical coating systems may be vulnerable also. Use with a PAI topcoat in magnet wire has already been commercialized by one firm. As in the case of the PAI's, some military specifiers noted that the 180C, thermal rating of PEI may be too high for use in high performance, hermetically sealed miniature traction motors. They have suggested down grading this rating to 155C. Thermal aging tests are being conducted by one supplier. If a lower rating does result, it would markedly reduce PEI's growth, since a 180C, rating is critical to specification in several markets. . . . DSW 200334 C-377 SKEIST LABORATORIES, INC. STLCOPCB4058398 Molded Parts DuPont fabricates its "Polymer SP" PI resin into finished parts, shapes and abrasive products under the "Vespel" trademark. Bar stock (%-2" thick) is available for test purposes at $4/cu. in. Machined blanks arc also custom sold. PI solid parts are rigid, hard materials, usable at continuous temperatures of 500F. and over. They combine excellent mechanical, thermal and electrical properties, low coefficient of friction, resistance to ionizing radiation, good low temperature, and high bearing PV limit. As the resin does not melt and cannot be molded on existing commercial equipment, proprietary fabricating equipment based on high pressure, metallurgical processing tech nology was developed at great cost. Some of this technology parallels the approach used in developing fluorocarbon processing techniques. A few other firms have attempted to mold PI products from resin supplied by other firms. Dixon Corp. (Bristol, R. I.), an important producer and marketer of Teflon high-performance parts, began producing "Meldin'1 PI parts and shapes in 1966, from resins supplied by unnamed sources (possibly Monsanto or Cyanamid). This program was a logical extension of their position in the Teflon component market. American Cyanamid has been developing an injection- moldable PI which can be processed on most conventional equipment with mod ifications. Amoco has also developed PAI resins that can be molded. Precision Components. The most important outlet for molded PI products will be precision components for low friction, high temperature applications in aerospace, military, electrical/electronic, and industrial markets. The poundage will be small but the dollar volume and profit substantial. Items under development, or in use include engine parts (e.g. backup rings), seals, ball-bearing cages, piston rings, ball valve seats, O-rings, bushings, gear wheels, vanes for rotary compressors, thermocouple plugs (extruder); insul ators in oil-well logging instruments, relay components such as coil bobbins and activators (which may be punched from sheet), terminal covers for pres sure transducers. Total volume of PI molded products is hard to identify since many are classified, and other parts are custom made or sold as shapes for machining. Estimates of rapid growth are based on the assumption that Cyanamid, Monsanto and others will offer PI resins to the molding trade. Grinding Wheels. The production of Pi-bonded diamond grinding wheels by DuPont is a separate market, apparently not related to other PI programs. The advantages claimed include better wear, greater cutting rate and a finer surface on ground parts. On a total service basis, these expensive (several hundred dollars) wheels may be reasonably priced. DuPont evidently has. concentrated on large accounts where diamond wheels are used for tungsten rods. This approach allows bypassing of the complex distribution system where much of the grinding wheel volume is sold. The first Pi-based wheels had an all-PI cover and edge. Reportedly, only the edge is now PI, so that PI volume will be small even if unit, growth is high. (Profit of the wheel rather than just PI is the obvious objective.) Several existing producers of phenolic-based grinding wheels (resin content is 10-25%, the abrasive and filler constitute the remainder) have tried to produce similar wheels from PBI and PI polymers with little success, C"378 SKEIST LABORATORIES, INC. DSW 200335 STLCOPCB4058399 They note that phcnolics flow in process, melting at 80-90C.; therefore, they can be used in either hot or cold processes. With Pi's, one firm claims that even a hot press is inadequate. Although phcnolics are cheap (31$/lb.), thev lose properties at 300C., while the Pi's maintain strength at roughly 100C. higher. (At room temperature, Pi's advantages are negligible.) Lubrication. See end of chapter regarding molded parts and other PI products as lubricants or carriers for lubricants. Injection Molding. American Cyanamid's Plastic Division has developed a thermoplastic polyimide (XP-182) that can be injection molded. Processing conditions include cylinder temperatures of 630-640F., molding temperatures of 400-450F., and cycle time of 30 seconds to several minutes. Shapes have performed well up to 500F. continuously in air for extended time periods. Modifications (e.g. heaters on screw-ram machines) seem to be within the technical and economic capabilities of many precision molders. Depending on volume, 1968 prices were $12.50-25.00/lb. XP-182 differs from conventional Pi's as it is thermoplastic, soluble in certain solvents, can be processed on modified molding equipment, and does not require heat treatment since it is processed as the polyimide. While data sheets indicate that this material does not possess the high-temperature properties of the Vespel products, there appears to be an attractive potential for XP-182 in engineered parts with less critical thermal requirements. The availability of this material to the-molding trade will make a strong contribution to its commercial success, (DuPont does not sell PI molding materials.) In 1968, volume was less than 50,000 pounds. Major applications will be in high-performance electrical/electronic parts. Several of these were in prototype and small-scale use in 1968, including several classified com ponents. In the future, expected applications among the electrical/electronic components will include electromechanical parts for aerospace, connectors, switches, part carriers for integrated circuits, gears, etc. Depending on volume, 1972 prices could be in the $2 to $5/lb. range, with the higher price range more likely. Volume is projected at 0.3 million pounds in 1972, but could grow much faster during the next five years as the molding industry, learns to process these resins. ' American Cyanamid has not revealed the chemistry of their XP polyimides. However, Netherlands Application 6,603,420 may provide a clue; it cites 3,4-dicarboxy-l,2,3,4-tetrahydro-l-naphthylene succinic dianhydride and derivatives. Preparation involves reaction of styrene and maleic anhydride under nitrogen to yield tetrahydronaphthylene succinic dianhydride adduct; then m-phenylene diamine (MPD) and DMF are added to yield the polycarbox amide (amic acid) which, on heating, gives the polyimide. Substitutes for MPD, e.g. p,p'~diaminodiphenyl methane, p,p`-diaminodiphenyl ether and other . amines, are cited. . Because of its solubility, XPI-182 type polymers have been studied for reinforced plastic binders and coatings. Cyanamid's Bloomingdale Division has been a leading developer of'T'M-34" structural adhesives from various PI materials. . DSW 200336 C-379 SKE1ST LABORATORIES, IMC. STLCOPCB4058400 In France, Rhone Poulenc introduced M-33 PI in 1968, Molded pieces capable of taking 200-250C, service temperature were noted at the Milan (1968) Plastics Show. Binders - Reinforced Plastics DuPont and Monsanto have been pioneers in this market. Others (e.g. Cyanamid, Amoco, Narmco, TRW) have also developed materials. DuPont has favored selling a PI prepreg (e.g. PI 2501 B-stage glass prepreg and PI 3301 for prepreg roving) to the user while Monsanto has sold its Skybond 700 Pi's to impregnators who, in turn, supply the prepreg to the user/fabri cator. The DuPont and Monsanto-based prepregs can be fabricated by conventional vacuum bag and autoclave processing. They are mainly intended for struc tural parts in high-performance aircraft where retention of mechanical properties at elevated temperatures is required (e.g. SST). Honeycomb cores, printed circuit boards, and bonding plies for honeycomb-to-skin applications have been under study. Specific structural parts under evaluation include de-icer ducts, inner fusilage, wing panels and leading edges, wing-to-body fairings, fin tops, deflectors, nose fairings and radomes, radiation covers, turbine components. Filament-wound PI composites have been suggested for radomes, ' As of late 1968, PI prepregs with glass or carbon fiber appeared to be favored for several SST honeycomb and sandwich panel-based structures. Estimates of PI composite use vary from 10,000 to 20,000 sq.ft, per plane. (This includes "all" PI honeycombs as well as PI glass structures.) Based on 38" wide sections per plane, and 45-50% resin loading, about one-half lb. of Pi/yard would be required, or 6,500-7,500 pounds/plane. Using one figure of 155 planned planes, total PI consumption might be in the million pound ' range over the six or more years required for delivery. Some estimates point to 1.5-2.0 million pounds of PI in composites if military craft (e.g. F 111 fighter planes) are included. Selected impregnators who have worked with PI composites include Hexcel (Dublin, Calif.); Coast Mfg. (Livermore, Calif.); HITCO (Gardena, Calif.), and Honeycomb Products (Fredericktown, Ohio). Many of the major aircraft firms have done independent work. Monsanto's Pi's have had more exposure since a wide group of impregnators have had the chance to work with them. Skybond 702 and 703 are high solids,.low viscosity Pi's (see U.S. Pats, 3,190,856; 3,260,691 and 3,347,808 for more detailed data). Both Skybond 702 and 703 use N-methyl pyrrolidone as the solvent; 703 does not have the extremely high-temperature resistance of 702 but is more . readily processed. The "wet" varnish sells for about $4/lb. (at 60% solids) or about $7/dry pound. Skybond 703 has been modified by the Brunswick Corp. to attain an essentially void-free material. Impregnators who tried the ' Quantum "Quantad 159" indicate that cure cycles were longer and required higher temperatures than competing materials. TRW's material had not been adequately tested as of late 1968. DSW 200337 C-380 SKE1ST LABORATORIES, IKC. STLCOPCB4058401 Adhcsivcs PI. During the early design stages of the SST, it appeared that con siderable quantities of Pi-based structural adhesives would be used (e.;;, American Cyanamid's "F 34") to bond titanium skins to Pi/glass honeycomb on fixed and movable wings, etc. Boeing issued a tentative SSI' adhesive specification (BMS-5-53) written around PI systems. By mid-1968, specifiers indicated that there was need for improvement in PI adhesives for bonding titanium honeycomb (brittleness was cited) in high-temperature environments. Under study are several other materials, one of which is bcnzimidazole-imide copolymers. It has been suggested that some Westinghouse polymers, perhaps 1-40 and/or 1-66, may be in this category. On the earlier designs, all of the honeycomb structures exposed to elevated temperatures had two layers of a high-temperature adhesive. This form represented about 75%, with the rest lap bonding. Based on consumption of about 0.1 lbs./sq.ft. (80% PI, 20% glass carrier) and 40,000 sq.ft, of glue line per plane, plus about 20,000 sq.ft, of "overage", 5,000-8000 pounds of PI adhesive was needed per plane (0.5-1.0 million pounds over several years). The decision not to use PI will reduce consumption to a small percent of the original potential. (Some may still be used in lower temperature areas.) Among the active firms in PI and related adhesive systems are American Cyanamid (Bloomingdale Division), DuPont, Narmco and Shell. Narmco's Metalbond 840, for example, has been offered for use on the SST, 747, C5 engine and Phoenix missile, PAT. TR 150-2T, made by Thermo Resist, Inc. (Fullerton, Calif.) also has potential adhesive applications. Some end users commented that PAI adhesives were as difficult to use as PI, without any advantages. Fillers (e.g. aluminum and arsenic compounds) have been incorporated in several of the PI adhesives presented to the industry. Fibers . Polyimide fibers have been under development by DuPont's Textile Fibers Department and others (e.g, ICI Brit. Pat. 1,037,374). The DuPont research fiber offers excellent thermal resistance, strength, dimensional stability, flame resistance, light stability, and resistance to organic solvents and hydrolysis by water or acids. Possible uses would be in high-performance industrial fabrics. Commercialization is not likely before the early 1970's. One contact indicated that earlier samples did not have adequate flame re sistance. Semiconductors Research in various areas of the world have indicated that pyrolyzed polyimide may offer promise as a high-temperature semiconductor. Studies by Dr. Bruck at Johns Hopkins on vacuum-pyrolyzed H-film indicated satis factory properties for electronic applications. In the past, other organic materials have been pyrolyzed to give highly conjugated, unsaturated products e.g. polyvinylidene chloride and polyacrylonitrile. See DuPont's U.S. . Pats. 3,073,784-5 for more background on electrically conductive materials. C-381 SHE 1ST LABORATORIES, iNC. DSW 200338 STLCOPCB4058402 Foams Several foam products for the SST are under development. These are still very high-priced, exotic materials. Brunswick Corp. has made PI foams (syntactic type) as a possible lightweight material for foam sandwich radomcs. Hexcel Corp. has made PI foams for joining honeycomb splices, for filling in various structures to eliminate water pockets, and for related applications. Similar foam applications with conventional adhesives are used in subsonic aircraft. Narmco has made syntactic PBI and PI foams using glass, silica or aluminum "microspheres'' for possible use in heat shields, microwave windows and radomes, A major objective of this research is to develop foams which can be used in supersonic structural and insulation applications, by providing low thermal conductivity and stability, high strength/weight ratios and excel lent ablative properties. Lubricants Research indicates that PI materials show promise as metalworking lubri cants as they provide substantial quantities of pyrolytic residues (that lubricate) during the extrusion of metals. Several contacts cited the potential of PI and filled PI (e.g. with graphite) parts for self-lubricating applications. One stated that under high pressure and temperatures, Vespel parts impregnate metal shafts, reducing the coefficient of friction. The self-lubricating properties of PI have also been noted in ball-bearing cages which must perform at high temperatures and/or vacuums where ordinary lubricants cannot be utilized. Specific applications where PI (natural or filled) is or will be used include backup rings in jet aircraft engines, gear wheels operating at high temperatures, terminal covers for precision pressure transducers, and a multitude of frictional components requiring the retention of dimensional stability and strength at high tempera tures. . DSW 200339 C-382 SKEIST LABORATORIES, IHC. STLCOPCB4058403