C. S. GROVE, JR. ROBERT S. CASEY M. J . COPLAN
J . L. V O D O N I K
DEVELOPMENTS IN FIBER TECHNOLOGY
Man-made Jibers now account f o r about 50%
o f all fibers used in industrial products. Strong impetus exists to produce ultrajne Jibers
nother year has passed without the introduction Research has been directed toward improved versions of existing fibers for special properties and end uses. Under the pressure of military and space requirements, some modest advances in the development of high modulus, high strength, and thermally durable fibrous materials have been noted. One novel item of particular interest is the application of oxide fibers as reinforcement for metallic matrices to improve tensile behavior. Research continues on chemical modifications, including the use of ionizing radiation, and treatments of man-made and natural fibers. Antistatic, antibacterial, flame-retardant, and weather-resistant treatments have been reported. Decreased cost of production and chemical modifications of cotton’s properties permit competition with man-made fibers for some specialized industrial markets. Interest in developinq new products and cheaper processes using papermaking technology is indicated by the growing number of joint effort programs by old-line textile and paper concerns of some renown. So-called “textryls” appear to be attractive wet-formed webs, and rea expected to be strongly competitive in the nonwoven field. Newer polyester fibers are beginning to find uses both in apparel and industrial applications. Their introduction as tare yarns is a deuelojment to watch.
A of a totally new American fiber.
Announcements of modified cellulosics for high wet strength and recovery continue, and ceramic fibers and systematic study of filter fabrics have received attention. These developments were noted during the period June 1961 through March 1962. Economics
Man-made fibers now account for about 5ooj, of the fibers used in industrial products, principally tires, reinforced plastics, auto and bus upholstery, belting, thread, rope, and filter fabrics. The noncellulosics, especially, are expected to continue their expansion. But olefins are expected to make the greatest percentage increase. The rapid increase in the use of textile glass fibers over the past decade and a half was interrupted by a decrease in 1961. Mergers, increasing emphasis on research, and development of improved machinery and production methods are notable trends in the industry. Foreign activity continues to increase, especially in the USSR and Japan. 70
Fiber Cotton Wool Cellulosics Noncellulcsics Textile glass
of Total Fabers Marketa 1960 1961 66 6 16 10 2
64 6 17
11 2
1961 U S . Man-Made Fzber Production a Millions of Yo Change Pounds from 1960
Fiber Acetate Rayon Noncellulosics Textile Glass Total a (2A).
793.3 302 . O 742.5 146.8
1984.6
i-7 +5 +IO 18 -
+4
(Continued on next page) VQL.
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T h i s photograph, shows evidence of E glass jibers sintering in an aluminum matrix. T h e nonnietallic fibrous reinforctd metal comfiosite itas subjected to temperatures of about 400' C. for iarjing time periods Courtesy .tlnterioir iicreoirh Co,p.
High Temperature Fibers
In the high tempprature fiber field, progress along several different lines has been reported. Organic fibers have been the subject of improvement studies at the Polytechnic Institute of Brooklyn (2B) Work conducted by personnel at the Aeronautical Systems Di\,ision, U. S. Air Force ( 7 B ) sho\vs that further improvements in the capabilities of the Du Pont HT-1 fiber may be achieved by gamma irradiation. Details of the thermal and mechanical prcperties of HT-1 have been published (7213). A Japanese fiber called Tayentex is reported with durabiliq- up to 750' F. in inert atmosphere; short term exposure to 6000' F. is also reported to be tolerable. Polybenzimidazole, a polymer reported to have durability to 600' C. ( 3 B ) , has now been reported to have been spun into fiber under a government contract. Metallic fabrics have received some attsntion, particularly under government research activities. Properties of fine filaments composed of high temperature alloys and some refractory metals are reported at length ( 6 B ) . Progress in the development of textile cloths composed of multifilament fine metal wires is also reported ( 1 B ) . 4 progress report of the work in this area was also given in the general literature (lOBj. I
56
INDUSTRIAL AND ENGINEERING C H E M I S T R Y
It'hile not strictly speakiiig a textile application by any means, high temperature oxide fibers are finding new uses as reinforcement in metallic s>-stems. Announcement was made at the American Rocket Society's meeting in Palm Springs last year of a composite material, half niobium alloy and half sapphire crystal whiskers. Reinforcing effect of high temperature aZu?ninum oxide rehiskers is expected to result in a four-to-one strength-to-weight ratio improvement, particularly in high temperature service. Research in this area is further reported (8B, 13B, 74B, 16B). Strong. impetus for the development of a number of techniques to produce ultrafine oxide fibers springs from the attractive prospect of realizing nearly theoretical atomic bond strengths. Lattice bond strengths in the order of 1.5 to 2 million p.s.i. have been calculated. Occasional experimentally produced oxide fibers, such as
AUTHORS Myron J . Coplan zs Associate Research Director for Fabric Research Laboratories, Inc. C. S. Grove, J r . , is Professor of Chemical Engineering at Syracuse LTniversity. Robert S.Casey is Research Chemist for W . A . Sheafer Pen Co. Joseph L . Vodonik was with Minnesota Mining and Manufacturing Co. when this article was written.
silica alumina, beryllia, zirconia, have exhibited strengths upward of 500,000 p.s.i. and once in a while approaching 900,000 p.s.i. Such values are almost 10 times larger than found in bulk bodies and have been achieved primarily in ultrafine (micron diameter range) filaments. Frequently, but not always, these ultrastrong, ultrafine fibers have been grown as whiskers. Achievement of bulk fabrication methods for producing ultrastrong $laments other than by growing whiskers i s an extremely exciting goal. One approach to that end was described (5B) by Armour Research Foundation at the A.R.S. meeting, April 3, 1962. “E” glass rods are heated and drawn directly to fibers and immediately coated with a molten alloy (95 A1-5 Si or 80 Pb-20 In). Bundles of these coated filaments are assembled and fed into a tube of glass and the entire assembly is redrawn. The process can be repeated until eventually the product consists of thousands of continuous filaments of diameters as low as 0.1 micron embedded in the alloy matrix. Details of this work appear in a series of quarterly reports (77B). Polifen is a Russian fiber wet spun from an aqueous dispersion of polytetrafluoroethylene; after sintering above its crystalline melting temperature and cold drawing it has high chemical and thermal stability ( 75B). Hitco-C is an erosion-resistant ablative material, 9801, carbon, made by Thompson Fiber Glass, in fiber and fabric form, which withstands over 3000 O F. ( I7B). High Temperature Materials has a pyrolite graphite alloyed with boron, which has high bending strength above 3500OF. (9B). Long, staple fibers of aluminum silicate are used for high temperature insulation and filters, up to 3000 F.
(4B) ’ Chemical Modification and Treatment
Considerable sophistication is evident in the chemical finishing of textiles. Nonresinous chemical treatments of conventional fibers aiming a t direct reactions with the polymeric substrate are being applied to achieve desirable effects : introduction of disulfide links in cotton, grafting styrene on nylon, interfacial polymerization of Nylon 66 on wool. Work on the modification of polymers, both natural and synthetic, has resulted in promising improvements of physical properties. Russian scientists have made water-repellent cotton fabrics by surface esterification of the cellulose with acid chlorides of chlorovalerianic acid (4C). Pilot plant treatment of cotton with formaldehyde to impart crease resistance and dimensional stability has been reported (2C, 3C). Vinyl monomers were radiation and chemically grafted onto cotton-based filter paper (QC). Styrene was grafted onto cellulose by gamma ray induction (5C). Grafting of a monomer onto a polymer in solution by gamma irradiation shows promise as a method cf improving properties. Russians grafted acrylonitrile and styrene onto natural silk, rayon, and Kapron by this method. Styrene grafted onto nylon fabric produces a superior water-repellent fabric (IC). Improvement of rayon has continued. Hartford
Fiber’s polynosic, Zantrel, is on the retail market (8C). The Nitto Spinning Co. of Japan has rayon with lower wet elongation and higher wet tenacity. Avril, American Viscose’s high wet modulus rayon, is in pilot plant production (7C); Courtaulds has a new permanently crimped, cross-linked rayon, Corval 11, and a n improved Trice1 H with higher strength and abrasion resistance (6C). American Enka is producing a high tenacity rayon, Suprenka Hi Mod. Avlin, a similar fiber, has been improved. The cycloparaffinketoxime process is Toyo Rayon’s new, cheaper method for making nylon.
BI BL I OG RAPH Y General and Economics (1A) Harris, M., Mark, H. F., “Natural and Synthetic Fibers Abstracts,” Interscience, New York, 1961. (2A) Textzle Organon 33, N o . 2 (1962). High Temperature Fibers (1B) Coplan, M. J., Fabric Research Labs., Inc., Aeronautical Systems Division, Wright-Patterson Air Force Base, Ohio, Tech. Rept. 61-677. (2B) Eirich, F. R., Brooklyn Polytechnic Inst., Final Report; Contract N140(138)67604B, U. S. Navy, Armed Srrvices Technical Information Agency, Arlington, Va., No. 266795. (3B) Fibres Plastzcs 22, No. 5 , 125 (1961). (4B) Zbzd., 22,No. 6, 170 (1961). (5B) Islinger, J. S., Armour Research Foundation, American Rocket Society, Phoenix, Ariz., April, 1962. (6B) Johnson, D. E., Arthur D. Little, Inc., A.S.D. Tech. Rept. 62-180. (7B) Little, C. 0.. Jr., A.S.D. Wright-Patterson Air Force Base, WADD Tech. note 60-299., ASTIA 266328. (8B) Machlen, E. S., Contract NOW61-0209-c, Materials Research Corp., ASTIA 265943. (9B) Materials in Deszgn Eng. 54, No. 2, 168 (1961). (10B) Zbzd., 54, No. 11, 117 (1961). (11B) Zbzd., 54, No. 12, 142 (1961). (12B) Zbzd., 55, No. 2, 12 (1962). (13B) Parikh, N. M., Fiber Reinforced Metals and Alloys, Armour Research Foundation, Contract NOas 60-6081-c. ASTIA 255992. (14B) Raynes, B. C., Horizons, Inc., Contract NOW 61-0207-c, ASTIA 267891. (15B) Segal, M . B., Koziorona, F. M., Khzm. Volak, 1961, No. 3 , 37. (16B) Sutton, W. H., Contract NOw60-0465-d; Space Sciences Laboratory, General Electric Go., Rept. R6ISDlOS. (17B) Weil, N. A., others, Armour Research Foundation, Contract NOW-61-0259-c with Bureau of Naval Weapons, ASTIA 259,754; 265,748; 269,177. Chemical Modification and Treatment (1C) Can. TextileJ. 78, No. 22, 41 (1961). (2C) Chance, L. H., Perkins, R . M., Reeves, W. A., Textile Research J. 31, 71 (1961). (3C) Zbid., 31, 366 (1961). (4C) Khoostenko, N. M., Vei-gaii, C., Rogavin, Z. A,, Zhur. Priklad. Khim. 34, No. 3, 656 (1961). (5C) Kobaycishi, Y . , J.PolymerSci. 51, 359 (1961). (6C) Modern Textiles M a g . 42, No. 2, 6 (1961). (7C) Zbid., 42, No. 3, 73 (1961). (8C) Zbid.,42,No. 11, 56 (1961). (9C) Schwab, E., Stannett, V., Hermans, J. J., Tap& 44, 251 (1961).
Information contained in government research contract reports on deposit with the Armed Services Technical Information Agency, Arlington 25, Va. can be obtained only by gualzjed personnel. VOL. 5 4
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AUGUST 1 9 6 2
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