Spinning hydrocellulose fibres into zinc-free precipitation baths

Conclusions -- It has been found that the introduction of sodium vinyl sulfonate into the solvent alkali does not exert any important effect on the properties of the viscose, with the exception of stabilizing the cellulose xanthate and retarding its coagulation under the conditions of viscose ripening.-- Sodium vinyl sulfonate added to the dissolving alkali reacts with groups in the cellulose xanthate and to a very slight degree with hydroxyl groups in the cellulose.-- Fibres have been spun from the viscose containing sodium vinyl sulfonate, in the preparation of which it was possible to carry out a higher orientation stretch and to attain better physico-mechanical indices as compared with fibres from viscose containing no sodium vinyl sulfonate.Translated from Khimicheskie Volokna, No. 1, pp. 38–40, January–February, 1991.     

Temperature dependence of water vapor diffusion into hydrocellulose fibres

Conclusions -- Coefficients of internal mass transfer in the sorption of water vapor by hydrocellulose high-modulus Siblon have been measured.-- The extremal dependence of the velocity of the process on the magnitude of water vapor sorption is explained by devitrification of the cellulose, cluster formation of the sorbate molecules, and hindrance to sorption in the ordered regions of supermolecular structure.Translated from Khimicheskie Volokna, No. 6, pp. 31–32, November–December, 1990.     

Ecological problems in the preparation of hydrocellulose fibres

Translated from Khimicheskie Volokna, No. 2, pp. 30–31, March–April, 1991.     

Preparation of hydrocellulose fibres from solutions in tertiary amine N-oxides

Conclusions Preparation of homogeneous, readily filterable solutions of cellulose in tertiary amine oxides is possible by various methods.The DP level of the cellulose is sufficient for spinning fibre with satisfactory physicomechanical properties from these solutions.Translated from Khimicheskie Volokna, No. 1, pp. 32–33, January–February, 1983.     

Preparation of hydrocellulose fibres from highly concentrated solutions of cellulose in N-methylmorpholine-N-oxide

Conclusions -- The conditions in preparation of highly concentrated cellulose solutions can greatly affect the structure and properties of the fibres obtained.-- In the preparation of fibres from highly concentrated solutions of cellulose in MMO, a number of complications arise which hinder practical realization of the process.VNIIPV (Mytishchi). Translated from Khimicheskie Volokna, No. 5, pp. 24–27, September–October, 1992.     

Some special features in preparing hydrocellulose fibres and yarns from concentrated viscoses

Conclusions The possibility has been demonstrated of preparing hydrocellulose fibres and yarns with good strength and elastic properties from concentrated viscoses at an -cellulose content of 12% with a DP of 250 and an NaOH/-cellulose ratio of 0.68.Translated from Khimicheskie Volokna, No. 2, pp. 25–26, March–April, 1990.     

Structure of hydrocellulose fibres prepared from cuprammonium solutions by the spin probe method

Conclusions The structure of hydrocellulose fibres has been investigated by the spin probe method.Broad possibilities of this method for investigating the dependence of fibre structure on preparation conditions have been demonstrated.Translated from Khimicheskie Volokna, No. 1, pp. 28–30, January–February, 1988.     

Preparation of hydrocellulose fibres with increased elasticity from solutions of cellulose in n-methylmorpholine-n-oxide

Conclusions The deformation properties of hydrocellulose fibres spun from solutions of cellulose in N-methylmorpholine-N-oxide monohydrate are determined to a considerable degree by the character of structure formation in the precipitation stage.A considerable improvement in the deformation properties of hydrocellulose fibres has been achieved due to the realization of a process of crystallization of the MMO at a definite stage in spinning; this affects the formation of a supermolecular structure in the polymer system.Translated from Khimicheskie Volokna, No. 4, pp. 33–35, July–August, 1989.     

Effect of temperature on deformation behavior of hydrocellulose fibres plasticized with aqueous solutions of N-methylmorpholine-N-oxide

Conclusions An increase in the temperature of the plasticizing medium (aqueous N-methylmorpholine-N-oxide solutions) leads to a shift of the region of efficient plasticizing action in the direction of an increase in the values of the critical plasticizer concentrations which delimit this region.The observed anomalous shift in the region of efficient plasticizing action is connected with the temperature-concentration dependence of the limits of structural transitions of the polymer and plasticizer.Translated from Khimicheskie Volokna, No. 2, pp. 24–25, March–April, 1989.     

Process of preparing hydrocellulose fibres and films from aqueous solutions of cellulose in zinc chloride

Conclusions The possibility of preparing concentrated solutions of cellulose in zinc chloride and the properties of the concentrated solutions have been investigated.Experimental hydrocellulose fibres and films have been spun on laboratory and experimental units; these had properties close to those of ordinary viscose fibres and films, and excelled them in a number of characteristics (elastic modulus, knot strength).Translated from Khimicheskie Volokna, No. 6, pp. 6–9, November–December, 1988.     

Basic directions of research in the area of preparing carbon fibre materials based on hydrocellulose fibres

Conclusions -- A wide assortment of CFM based on viscose technical yarn has been developed in the VNIIPV and introduced into industry.-- Basic trends of studies in the area of preparing CFM based on HCF have been defined: improvement in the quality of viscose technical yarn; solution of ecological problems in its manufacture; optimization of technology with the purpose of improving characteristics and reducing costs; the development of CFM with qualitatively new characteristics; and the search for new regions of application.VNIIPV. Translated from Khimicheskie Volokna, No. 3, pp. 8–10, May–June, 1991.     

Fire-resistant aluminosilicate composites

The fire response of a potassium aluminosilicate (Geopolymer) matrix carbon fiber composite was measured and the results compared to organic matrix composites being used for transportation, military, and infrastructure applications. At irradiance levels of 50 kWm⁻² typical of the heat flux in a well-developed fire, glass- or carbon-reinforced polyester, vinylester, epoxy, bismaleimde, cyanate ester, polyimide, phenolic, and engineering thermoplastic laminates ignited readily and released appreciable heat and smoke, while carbon-fiber reinforced Geopolymer composites did not ignite, burn, or release any smoke even after extended heat flux exposure. The Geopolymer matrix carbon fiber composite retains 67% of its original flexural strength after a simulated large fire exposure. © 1997 US Government     

Effect of dissolving conditions on the structure and physicomechanical properties of hydrocellulose fibres spun from solutions of cellulose in N-methylmorpholine-N-oxide

Conclusions Hydrocellulose fibres have been prepared from solutions of cellulose in N-methylmorpholine-N-oxide which have been prepared by two different methods (traditional and accelerated).It has been shown that the properties of the fibres obtained depend on the method of preparing the spinning solution.The fibres which have been spun from solutions prepared by the accelerated method have elevated deformation characteristics; this is connected with their specific supermolecular structure.Translated from Khimicheskie Volokna, No. 2, pp. 17–19, March–April, 1990.