in the Chemical
and Chemical
Process
TEXTILES
Industries.
T e x t i l e s i n 1 9 5 4 began to creep out of a period of depression. A series of mergers a i d e d the upsweep in both synthetic and natural fibers A gigantic industry that has long suffered from overproduction, high capital investment, low profits, and insufficient technology is slowly emerging from a period of depression which has run its course during one of the most prosperous eras in history. Perhaps the outstanding feature of this emergence occurred during 1954 in t h e form of a series of mergers, in which mills which specialized in synthetic fibers acquired control of natural fiber mills and vice versa. Among the immediate goals of such mergers are t h e acquisition of m o d e r n facilities, improvements in capital position, diversifications in end products, and cutting of overheads through combinations of managements. A longer range result must be the development of better technology and the ability to utilize to greater advantage the constant innovation of chemical and mechanical impr o vem ents. Chemicals Find W i d e V a r i e t y Of Applications
Economic stability and technological progress of the textile industry are of prime importance to the chemical industry which finds o n e of its greatest markets in the textile fields. The following are examples of such applications, some new and some more or less in t h e form of progress reports on items which are on their time consuming path from laboratory to commercial application. T h e passage of t h e Flammable F a b rics Act has spurred interest in flameproofing finishes for textiles. Patents were issued for finishes based on a titanium chloride organic compound and on polyphosphonitrile ester. Chemical modifications of cotton have been slanted toward the improvement of flame resistance as well as of other properties. Cotton treated with lead chromate for better light resistance and acetylated cotton for better heat, rot, and acid resistance are commercially available. Cyanoethylated cotton, called "Azoton," with better heat, flame, rot and abrasion resistance, and enhanced dyeability is being produced in a pilot plant in which the acrylonitrile is recovered b y filtration and distillation, with jS,/§'-oxydipropionitrile, a solvent for separation of aliphatic and aromatic hydrocarbons, as a by-product. Aminized cotton for better chemiVOLUME
3 3.
NO.
2
•
JANUARY
M I L T O N HARRIS a n d JOHN
KRASNY
Harris Research Laboratories, Inc., Washington, D. C.
cal reactivity, and tetrakis (hydroxymethyl) phosphonium chloride ( T H P C ) cotton and cotton treated with an allyl phosphorus compound for enhanced flame. Rot and crease resistance were produced in large experimental quantities, while the treatment of cotton with /?-propiolactone and chloroacetic acid to improve its dyeing properties are in t h e trial stage. The commercial application of carboxymethylcellulose to cotton for improved soil resistance and ease of cleaning is being worked out. Pine oil and kerosine were used experimentally as tar spot removers and desizing agents. Chloromycetin and aureomycin were fed to silk worms to improve their production. The elongation of abaca was improved by treatment with caustic and a methacrylate-chromyl chloride complex, and a combined degumming and preshrinking process for hemp and flax was patented. Chemicals made further inroads as aids in fiber processing. There was more demand for water insoluble sizes such as vinyl copolymers because of the increasing use of dope-dyed yarns in fabrics which are not desized in finishing. T h e tendency of these sizes to stick to drying cans was overcome by silicones. Antistatic finishes containing such diversified chemicals as water-insoluble amine salts of sulfonated polystyrene, amine salts of longchain alkyl phosphates, and mixtures of soluble and insoluble hexitol esters and a long chain quaternary of the morpholine series w e r e patented. T h e manufacturers of silcones continue their bids for t h e textile finish market. Previously applied primarily to synthetics, silicones m a d e inroads as water repellents for cotton as more finishers acquired high temperature curing equipment, including infrared types. On the other h a n d , newer silicone finishes which require lower curing temperatures were used on wool 10,
1955
for water repellency, improved hand, crease resistance, and soil resistance. Other new water repellents include one based on stearate chromic chloride a n d polyoctadecyl vinyl ether. A comprehensive study of t h e fungicidal properties of 35 fluorinated q u i nones, hydroquinones, phenols, anilines a n d nitrobenzenes showed l-fluoro-3bromo-4,6-dinitrobenzene to b e most effective, while the l,3-dihalo-4,6dinitrobenzenes w e r e best as a group. A cationic resin was marketed as a nylon delustrant, a lanolin finish w a s said to improve t h e softness of hosiery, while polyvinyl acetate emulsions found their w a y into carpets, upholstery, and nylon hosiery. Research on shrinkage control -was active due to the continuing emphasis o n functionality of fabrics. N e w pattents for nonshrinkable wool include t h e use of methylolmelamine and exposure to a high frequency electric field, and of alkoxymethyl linear polyamides. The continuous chlorination process for wool shrinkage control found wider acceptance, and a n e w mechanical compressive shrinkage unit was announced. Trend to Faster Dyes Continues
In t h e dyeing field, the trend was to faster dyes as v a t dyes climbed from 3 1 % of all dyes consumed in 1952 to 3 7 % of the 166 million p o u n d s consumed in 1953. Almost all m a n - m a d e fibers are now available with the d y e or pigment introduced during spinning. Progress was reported in the development of commercial application of pressure dyeing for t h e synthetic fibers, though use of this method for wool blends was criticized. Dye carriers discussed in the recent literature include aminoalkyl esters of acrylic acid for vat dyeing of acetate. For polyethylene terephthalate fibers, xylene w a s recommended as a carrier for vat d y e 117
TEXTILES.
ing, methyl salicylate emulsions for dyeing with acetate dyes, a n d orthophenylphenol with disperse d y e s . From Hungary comes a report about "dyeless" dyeing a n d i m p r o v e m e n t of the hand of wool b y diazotizing it with sodium nitrite and acid. Glass fabrics could be successfully printed after treatment with polyacrylate latex emulsions with a Teflon dispersion. The National Science Fair prize was won the third year in succession by an 18 year old girl for exhibiting a discharge printing m e t h o d for Dacron. Several brightening solutions for nylon were developed for h o m e use, and British researchers continued experiments with peracetic acid for the same purpose. A source of u n r e a c h a b l e cotton was found t o be fungus growth promoted by weathering. Silicon-containing azo dyes for a c e t a t e showed promising light resistance. Diammonium p h o s p h a t e was r e c o m m e n d e d for p H control of dyebaths for wool, iso- and polyisocyanates to improve the wash and rubfastness of prints on cellulosic fibers. High Cost cf D e v e l o p m e n t Does Not Stop Interest in E x p e r i m e n t a l Fibers
In spite of warning t h a t developing and successful marketing of a new fiber may cost between $40 a n d $ T 5 million, activity continues high along this line. British researchers r e p o r t e d success with polyaminotriazole fibers which are melt spun at 256° C. a n d a r e said to have good dyestuff affinity and acid resistance; their commercial success will depend on t h e availability of low cost hydrazine a n d sebacic acid. In Japan, a mineral fiber was m a d e from igneous rock as a substitute for rock wool and glass fiber in insulation and reinforced plastics. T h e first fiber forming material to benefit by commercial application of radiation is a crosslinked, m o r e heat resistant polyethylene. Availability of a privately o w n e d nuclear r e a c t o r for fiber investigations might o p e n n e w vistas in the u n d e r s t a n d i n g of polymeric behavior. Radiation -was found to affect the specific gravity, hygroscopicity, light transmission, dielectric and stress-strain properties of polyamide, polyester, and polyethylene fibers (which are crosslinked) and of polyvinyl and polyvinylidene chloride, polytetrafluoroethylene, a n d cellulose (which are d e g r a d e d ) . Several modifications of established fibers m a d e t h e i r a p p e a r a n c e during the past year. A triacetate fiber under the n a m e "Arner* is said to liave many of t h e properties of acetate but to exceed it in h e a t a n d wet abrasion resistance and speed of drying; it is- con118
.C&EN's
siderably cheaper t h a n the fully synthetic fibers. Another n e w t y p e of acetate develops crimp u p o n boiling. High tenacity rayon and saponified acetate (Fortisan) are progressing from the industrial to the furniture a n d apparel textiles field. Several viscose fibers with high skin to core ratio a n d consequently low swelling a n d higher wet strength are commercially available. T h e USDA, in surveying the feasibility of use of b a m b o o for rayon pulp, suggested improving t h e reduction of pentosan and ash as o n e of t h e prerequisites. Several writers e m p h a size the future d e m a n d for hygroscopic woollike synthetics rather t h a n silklike synthetics. This d e m a n d will b e at least partially filled by t h e regenerated protein fibers such as t h e wellestablished U. S. zein-based fiber Vicara and the British fibers Fibrolane (casein) and Ardil ( p e a n u t ) . The utilization of chicken feathers, another a b u n d a n t proteinaceous r a w material, is still being studied. Of the new nylon plants opening up or being contemplated, only one chose nylon 66 while the others concentrate on nylon 6, based on caprolactam. Nylon 6 has a lower melting point and reportedly better dyeability a n d abrasion resistance than nylon 66. Other nylon developments include o p a q u e yarns and a fiber with fluted outer face, developed in Japan. Several n e w t y p e polyamide yarns were announced in Germany. Acrylic fibers are making progress in the world markets a n d there is considerable patent activity in this field. From Japan, a polyvinyl alcohol fiber with a tensile strength of 8 grams per denier was reported. In t h e U. S., Teflon, a polytetrafluoroethylene fiber, became commercially available for uses involving high chemical, heat, and electrical resistance. A m e t h o d for producing a web of randomly distributed rubber fibers for use in elastic pads and water-repellant materials was developed. M a n - M a d e Fibers M a d e M o r e Competitive By End-Use Research
One of the major developments in t h e man-made fiber industry is the broadening of the base of service it provides for its customers, b y a tremendous increase in its research activities in the fields of fabric technology, end-use development, a n d even physiological research to obtain a better understanding of fabric acceptance b y consumers. T h e results of this work can b e seen b y the several methods to overcome t h e lack of bulk of filamentous yarns, such as combining relaxed and stretched Orion tow, the
Annual
Review
of
Developments
use of air blasts on filaments during twisting, or the passing of thermoplastic yarns through stuffing boxes or twisting, heat setting and untwisting yarns to obtain crimp. T h e various processes to obtain "stretch" filament yarns also produce greater bulk and extensible end products, notably men's socks. Almost innumerable are the examples of the successful application of chemicals to allow man-made fibers to b e used in new end uses. A case in point is glass, which without chemicals would have few applications but which m a d e big strides in reinforced plastics (the production of which was estimated to have doubled in the last two years) and was introduced in such novel items as vinyl resin coated screens. Improved bonding of glass to resins was reported due to use cf allyltrichlorosilane. Nonwoven fabrics and carpet backing are growing outlets for latices of polyvinyl alcohol, acetate and chloride, polyvinylidene chloride, polyacrylic esters and acrylonitrile. A latex m a d e from vinyl pyridine is used as a clip for nylon tire cord, and nylon's tendency to creep in tires was overcome by heat setting. Coating of protective army apparel with polymerized monochlorotxifluorethylene, a fluorocarbon synthetic rubber, is also in pilot plant stage. Dacron appeared in felts and, because of its relative insensitivity to temperature, in parachutes. Polyethylene ropes m a d e their appearance for use in corrosive atmospheres. Nylon entered the bedsheet field, and rayon was increasingly used in carpets. T h e upholstery of many 1955 cars shows increased application of rayon, nylon, and metallic fibers, with nylon being estimated as 8% of the expected total. Metal yarns were reported on t h e increase in E u r o p e a n tires. G r o w t h of T e x t i l e Industry Seems Assured
All economic forecasts on textiles predict a tremendous growth in demand for fibers during the second half of this century. Such predictions are based largely on the present rate of increase in population, and t h e tremendous potential demand for textiles in undeveloped areas. The President's Materials Policy Commission estimates that man-made fiber production alone will grow from 1145 million p o u n d s in 1950 to 3250 million pounds in 1975. It would appear certain therefore that in spite of short-range difficulties in the textile industry, its longer-range influences on the chemical industry will be great indeed.
CHEMICAL
AND
ENGINEERING
NEWS
