Effect of polycaproamide melt temperature of the presssure-flow characteristics of spinneret holes

Conclusions The effect of fluctuations in polycaproamide melt temperature before the spinneret on flow rate of the melt through a spinneret hole, and, consequently, on the linear density of elementary filaments, has been investigated.It has been found that even a slight polymer melt temperature drop — even of 5°C — can lead to 12% variations in filament linear density.Translated from Khimicheskie Volokna, No. 3, pp. 36–37, May–June, 1985.     

Reducing water consumption in washing viscose textile yarn in packages

Conclusions The effect of specific flow rate of soft water on the intensity and extent of wash-out of viscose textile yarn in packages has been studied.A process of washing yarn on OK-I machines with a reduced consumption of soft water — down to 60 m³ per metric ton of yarn — has been developed and carried out in manufacturing.Translated from Khimicheskie Volokna, No. 1, pp. 44–45, January–February, 1987.     

Modification of polyacrylonitrile fibres with halogen-containing polymers

Conclusions The physicomechanical and relaxation properties of fibres based on mixtures of polyacrylonitrile with halogen-containing polymers — polyvinyl chloride, chlorinated polyvinyl chloride, and Ftorlon — have been studied.It has been found that on introducing small additions of HCP, the physicomechanical properties of the fibres rise in an extreme fashion.Translated from Khimicheskie Volokna, No. 2, pp. 44–45, March–April, 1984.     

Effect of rare-earth chromites on sintering of magnesia

The effect of neodymium, cerium, lanthanum, and yttrium chromites, added in amounts of not more than 8%, on the sintering of magnesia in air and in vacuum has been studied. On addition of rare-earth chromites, the initial magnesia is sintered to a density of 0.98. By their sintering action, these chromites fall into the following sequence: neodymium chromite — lanthanum chromite — yttrium chromite — cerium chromite. The highest density (0.98 – 0.99) and the lowest porosity (1–2%) are obtained on addition of 2% of neodymium chromite to magnesia. The process of sintering of magnesia is accompanied by an increase in the size of periclase crystals from 12 to 38–56 µm.Translated from Ogneupory, No. 1, pp. 2–4, January, 1994.     

Effect of plasticized stretch on the properties of carbon black filled halogenated carbo-chain fibres

Conclusions The effect of plasticized stretch on the physicomechanical and electrophysical properties of yarns based on carbon black filled polymers — 42V fluororesin and chlorinated polyvinyl chloride — has been examined.A number of features of these polymers have been discovered, and recommendations are made on choosing an optimum regime of plasticized stretch of carbon black filled yarns.Translated from Khimicheskie Volokna, No. 6, pp. 8–10, November–December, 1983.     

The Penetration Resistance of a Titanium Alloy against Jets From Tantalum Shaped Charge Liners

Titanium alloys, notably Ti—6Al—4V, are known to provide high mass effectiveness against kinetic energy penetrators. However, the penetration effectiveness of titanium against shaped charge jets has not been investigated in detail. An experimental study was conducted with Ti—6Al—4V billets impacted by shaped charge jets formed from 100–mm, 42° conical shaped charge liners fabricated from tantalum. This work represents the first study of hypervelocity, high–density jet penetration into titanium alloys.     

Origins of cross-sectional heterogeneity in wet-spun fibres

Conclusions 1. Phase changes have been studied in the polymer — solvent — precipitant system.2. It has been shown that, depending on the concentration and type of precipitant, three different methods of separation of polymer from solution are observed. The phenomena can be used to explain the origin of non-uniformity in the cross-section of wet-spun fibres.Leningrad Branch of the All-Union Scientific-Research Institute for Synthetic Fibres (VNIIV). Translated from Khimicheskie Volokna, No. 4, pp. 52–55, July–August, 1969.     

Two-stage method of synthesizing polyanthanthroylenebenzimidazole and preparation of a fibre based on it

Conclusions Polyanthanthroylenebenzimidazole has been prepared by a two-stage method. Some principles have been studied, and optimum conditions have been established for the first stage of the synthesis — preparation of the prepolymer.The possibility of cyclizing the prepolymer to polyanthanthroylenebenzimidazole has been demonstrated.Model yarn specimens have been prepared and a preliminary evaluation of their properties has been given.Translated from Khimicheskie Volokna, No. 1, pp. 29–32, January–February, 1987.     

Optimizing the process of filtering spinning solutions

Conclusions The question of optimizing the spinning solution filtration process with respect to a production criterion — the maximum gain in commercial production (profit) — has been examined.It has been shown methodically and experimentally that attainment of the maximum yield of fibre of highest quality as a result of increasing the cleanness of the spinning solution is attended with a deviation from the maximum profit.A procedure has been worked out, and specific example given, for calculating the optimum values of the filtration surface and charge density for typical manufacturing situations. It is recommended to use this procedure in plants which produce viscose, acetate, nitron, or other fibres.Translated from Khimicheskie Volokna, No. 6, pp. 8–12, November–December, 1985.     

Spectroscopic investigation of polymers dyed with fluorescent dyes — Naphthalimide derivatives

Conclusions 1. Naphthalimide derivatives are promising for the preparation of dyed and fluorescing polyamide, and especially acetate fibres. Thereupon dyeing of the fibres in bulk is a more economical and ecologically clean method than dyeing from solutions.2. The optimum dye concentration in the fibre — about 0.5% by weight — at which the fibre acquires a bright color and fluoresces intensively has been determined.Scientific Research Institute of Physical Chemistry, Moscow. Translated from Khimicheskie Volokna, No. 5, pp. 16–18, September–October, 1993.     

Effect of filler fibres on structure formation in cation-exchange membranes

Conclusions -- An attempt has been made to replace the inert reinforcing filler in ion-exchange membranes with an active material — man-made fibres.-- The membranes prepared conform fully to the requirements imposed on cation-exchange membranes.Saratov Polytechnic Institute. Translated from Khimicheskie Volokna, No. 5, pp. 29–32, September–October, 1992.     

Automation of package grading processes

Conclusions One of the possible schemes for automating package grading has been given.In developing automatic package grading, special attention should be paid to devising electronic instruments — fibre quality determiners.Translated from Khimicheskie Volokna, No. 3, pp. 20–23, May–June, 1989.     

Effect of alkaline earth metal or iron contaminants on properties of viscose

Conclusions The effect of salts of alkaline earth metals and iron on the physico-chemical indices of viscose — viscosity, ripeness, and filterability — has been investigated.In amounts which exceed the content allowed by the All-Union State Standard in viscose by a factor of 3–4, calcium and magnesium ions do not cause a significant impairment in the physico-chemical indices of the viscose.Even at a content of 28 mg/liter, the presence of trivalent iron salts in a viscose causes a sharp impairment in its filterability, especially on prolonged ripening.Strict control of the trivalent iron content of viscose during the process of preparing it for spinning is necessary.Siberian Technological Institute. Translated from Kimicheskie Volokna, No. 2, pp. 17–18, March–April, 1987.     

Morphological features of the structure of fibres prepared from solutions of cellulose in methylmorpholine oxide

Conclusions Structural features of fibres spun from solutions of cellulose in N-methylmorpholine-N-oxide into isopropyl alcohol have been studied.It has been found that the structural porosity of these fibres is determined to a considerable degree by the temperature of the precipitant — isopropyl alcohol.Translated from Khimicheskie Volokna, No. 1, pp. 27–28, January–February, 1988.     

Cuticular hydrocarbons of gregarious and solitary locustsLocusta migratoria cinerascens

The cuticular hydrocarbons ofLocusta migratoria cinerascens—larvae and adults, males and females, gregarious and solitaries—have been investigated by combined gas chromatography-mass spectrometry. The hydrocarbons comprise 52–78% of the cuticular lipids and are divided inton-alkanes (28.7–47.3%), 3-, 4-, and 5-methylalkanes (11.3–15.8%), internally branched monomethylalkanes (13.7–19.9%), and internally branched dimethylalkanes (19.8–35.9%) with seven or nine methylenes between the two branch points. While the sexual dimorphism does not seem to be reflected in the cuticular hydrocarbon composition, clear quantitative variations favoring the longest chain alkanes have been observed between gregarious and solitary locusts, thus revealing a new phase character in these insects.     

Linear copolymerization of unsaturated albumin derivatives with acrylamide

Summary The radical copolymerization of macromonomer — human serum albumin N-acryloyl derivative containing one unsaturated bond with acrylamide has been investigated. It has been found that the water-soluble copolymer of molecular mass about 10⁶, containing 4–5 chemically bound molecules of albumin is formed.     

Modifier for viscose technical yarn based on cotton soapstock acids

Conclusions A new domestic modifier for viscose technical yarn has been synthesized — Amiprin KhS-20, based on distilled fatty acids from cotton soapstock.Specimens of viscose technical yarn have been prepared under the conditions of an experimental unit, using Amiprin KhS-20 modifier. The properties of the yarn obtained are close to those of yarn spun using Berol'-Visko 314 as a modifier.Translated from Khimicheskie Volokna, No. 3, pp. 46–47, May–June, 1989.     

Effect of additions of oligomeric epoxides on the physicochemical properties of cellulose acetates

Conclusions The effect of oligomeric epoxides based on polyethylene oxide and epichlorohydrin, having an epoxy group content of 8–15%, on the physicochemical and structural—mechanical properties of solutions and films of CA has been described.It has been shown that, in the first stages of degradation, the modifiers are effective thermostabilizers (at a content from 0.5 to 10% of the weight of the CA).The devitrification region of the modified specimens is shifted in the low-temperature direction by 5–33°C on increase of the oligomer content from 2 to 15%; the relative elongation rises by a factor of 1.2 to 3.Under the influence of the modifiers, the viscosity and turbidity of concentrated CA solutions are reduced; the specific bulk electrical resistance of films containing modifiers is reduced by several orders of magnitude.Translated from Khimicheskie Volokna, No. 3, pp. 45–46, May–June, 1984.     

System for automated design of equipment for the manufacture of nonwoven materials from polymer melts

Conclusions A system for automated design of equipment for the manufacture of filamentary nonwoven materials has been developed — the SNM SAD. The system has been realized on an SM 1420 computer.An interactive regime of the SAD operation is used; and theoretical and empirical mathematical models have been employed for the basic technological processes in the preparation of nonwoven material; imitative modeling and optimization based on mathematical methods of experiment planning have also been used.Translated from Khimicheskie Volokna, No. 4, pp. 10–12, July–August, 1989.     

Determination of admixtures of isophthalic acid and monoisophthaloyl chloride in isophthaloyl chloride by liquid chromatography

Conclusions A procedure has been developed for determining monoisophthaloyl chloride and isophthalic acid in isophthaloyl chloride. A regime for chromatographing on glass columns has been worked out.It has been found that it is necessary to add an equimolar amount of N,N-dimethylacetamide to eliminate the effect of HC1 on esterification of the carboxyl groups.This procedure has made it possible to evaluate objectively the quality of one of the monomers in manufacture of a thermally stable, fibre-forming polymer — poly-m-phenyleneiso-phthalamide.Translated from Khimicheskie Volokna, No. 4, pp. 60–62, July–August, 1988.