Effect of quaternary ammonium compound preparations on poly(ethylene terephthalate) fibre

Preparations based on quaternary ammonium salts (QAC) can have a plasticizing effect on PET and can also play the role of a catalyst of hydrolysis of cyclic oligomers — both complete and partial. The intensive migration of oligomers to the surface of the polymer material is due to their plasticizing effect, and the oligomer content in the internal regions of the fibre decreases, but the content on the surface increases as a result. Fulfilling the function of a catalyst of hydrolysis of cyclic oligomers, the QAC preparations cause these oligomers to be removed from the surface of the fibre materials by enhancing formation of soluble oligomers in linear form and TPA. As a function of the type of preparation, both the first and the second functions can be executed or they can be combined. By correctly selecting the QAC preparations, it is thus possible to regulate the oligomer content in the inner regions and on the surface of a fibre material. __________ Translated from Khimicheskie Volokna, No. 6, pp. 17–20, November–December, 2007.     

The modifying effect of weak aqueous solutions of ammonia on poly(ethylene terephthalate) materials

The effect of water and aqueous solutions of ammonia of 0.02–0.04 M concentration on poly(ethylene terephthalate) and fleecy knit fabric was comparatively investigated at high temperatures. It was found that migration of oligomers to the surface of the polymer, partial hydrolysis of cyclic oligomers to the linear form, and total hydrolysis to TPA are possible under the effect of water, but water affects the knit much less than the film. The presence of ammonia intensifies the processes that can take place with oligomers of PET at high temperatures to a significant degree. The concentration of ammonia in the system determines which of these processes will predominate. It was found that a 0.015–0.03 M concentration of ammonia is optimum for refining polyester fibre materials. __________ Translated from Khimicheskie Volokna, No. 6, pp. 15–18, November–December, 2006.     

Nature of the effect of decreasing the electrical resistance of polyethylene terephthalate with aqueous solutions of ammonia

The nature of the effect of decreasing the electrical resistance of polyester fibres with low-concentration solutions of ammonia at high temperature was investigated. The results obtained suggest that the stable antistatic effect obtained is due to the formation of a conducting layer on the surface of the polymer as a result of partial ammonolysis and hydrolysis of surface cyclic oligomers. Translated from Khimicheskie Volokna, No. 3, pp. 33–35, May–June, 1998.     

Effect of structural modification of polyester fibres on the strength of nonwoven materials

The positive effect was established and the optimum technological parameters of treating the surface of polyester fibres with a solution of NAOH, a quaternary ammonium compound — Catamine AB, and organosilazanes on the strength characteristics of nonwoven materials in autoadhesive bonding of fibres were determined. The advantage of organosilicon modifiers was demonstrated. A 13-fold increase in the strength of nonwoven materials was obtained with the optimum concentration of the preparation on the fibre of 0.27 wt. %. Moscow State Textile Academy. Translated fromKhimicheskie Volokna, No. 4, pp. 54–55, July–August, 1999.     

Fabrication of polyester decorative upholstery materials with low combustibility

The efficacy of the flameproofing effect of alkylphosphonic acid ammonium salt for polyester materials was investigated. It was shown that treating materials with a 12% solution of APAAS (alkylphosphonic acid ammonium salt) resulted in difficultly ignitable materials. Materials characterized by high surface density and thickness acquired higher flameproofing indexes. The study of thermolysis of polyester materials treated with APAAS showed that this flame retardant causes the formation of carbonized residue of a certain mass, composition, and structure which reduces the combustibility of the material. The flameproof properties of polyester fabrics modified with APAAS persisted over multiple chemical cleanings. __________ Translated from Khimicheskie Volokna, No. 5, pp. 50–53, September–October, 2006.     

Fabrication of textile materials with a combined biological effect

Formation of a protease C—polyhexamethyleneguanidine hydrochloride polyelectrolyte complex was demonstrated by nephelometry and an analysis of the activity, stability, and physicochemical properties of immobilized protease C. The effect of the composition of the polymer composite used for modification of fibre polymer supports on the properties of the materials obtained was investigated. It was shown that cellulose and polyester fibre materials fabricated by the method developed and containing immobilized protease C and the high-molecular-weight antimicrobial polyhexamethyleneguanidine hydrochloride have prolonged enzyme and antimicrobial activity. Moscow State Textile Academy. Translated fromKhimicheskie Volokna, No. 2, pp. 8–11, March–April, 1999.     

The modifying effect of ammonium nitrate and sodium hydroxide on poly(ethylene terephthalate) materials

The characteristics of modification of PET with aqueous solutions of equimolar amounts of ammonium nitrate and sodium hydroxide are investigated. It is shown that such treatment of the polymer is not equivalent to treatment with weak aqueous solutions of ammonia. It removes a significant amount of oligomers contained in the polyester but does not cause their intensive decomposition. It was found that this modification can increase the dyeability of polyester material and decrease the electrical resistance by 10–100 times in the most severe conditions.Translated from Khimicheskie Volokna, No. 6, pp. 19–21, November–December, 2004.     

Surface modification and dyeing of polyester fibres using magnetically activated aqueous solutions

For surface modification of polyester fibres in an alkali bath, dyeing them with disperse dyes, and successively performing these operations, the water must be magnetically activated. The color characteristics and degree of surface alkaline hydrolysis are a function of the magnetic field strength. The optimum current strength in the electromagnet is approximately 1.6 A. __________ Translated from Khimicheskie Volokna, No. 4, pp. 41–44, July–August, 2007.     

Development of technology for high-strength nonwoven materials

It was found that chemical fibres modified with organosilicon compounds have better physicomechanical properties than the initial fibres. The effect of the chemical structure and properties of the organosilicon compounds on the modification process and physicomechanical properties of the modified fibres was investigated. The optimum process parameters for manufacture of thermobonded nonwovens with elevated physicomechanical properties were determined. It was shown that treatment of the fibre web with a catalyst — hydrogen peroxide — allows eliminating the stage of heat treatment of the webs after application of the modifier which reduces the power consumed for production of nonwovens. __________ Translated from Khimicheskie Volokna, No. 2, pp. 21–23, March–April, 2006.     

Flameproofing modification of synthetic materials by laser radiation

A method of giving flameproof properties to materials and articles in light industry by modification with phosphorus-containing flame retardants under the effect of the energy from CO₂ laser radiation was developed. The optimum modification parameters (LR power density of 5.3 W/cm², treatment time of 30 sec, concentration of flame retardant (FR) in 5–10% solution, impregnation time of 100–120 sec), which allow obtaining flameproof materials with high performance properties were determined. The oxygen index of the cloth increased to 29.5–42%, the breaking strength increased by 8.5–21%, and the abrasion resistance increased by 5–12% without worsening the hygroscopicity and air permeability. The activating effect of laser radiation on the modification process was demonstrated; it resulted in an increase in the sorption capacity of the fibre structure of the materials, diffusion of FR into the bulk of the fibres, uniform distribution of the fibres in the form of finely disperse particles, intensification of the reaction of the components, ordering of the structure, and improvement in the physicomechanical properties of materials and articles in light industry. The method saves on expensive raw materials — flame retardants — due to conducting the modification from low-concentration solutions and allows expanding the line of flameproof materials. __________ Translated from Khimicheskie Volokna, No. 1, pp. 48–52, January–February, 2008.     

Anisotropy of Wrinkling of Polyester, Polyester@mdash;Linen, and Linen Fabrics

The anisotropy of wrinkling of polyester, polyester—linen, and linen fabrics in standard conditions and in a maximally humid environment was investigated. It was shown that wrinkling of polyester fabric is close to isotropic, whilie polyester—linen and linen fabric exhibits anisotropy to a greater degree the higher the linen content is. An incrasei n the humidity increases wrinkling of the fabrics in all directions, the difference in comparison to the standard state is insignificant for polyester fabric, but is very pronounced for linen, and the blended fabrics fall in the middle. Translated fromKhimicheskie Volokna, No. 6, pp. 49–51, November–December, 2000.     

Effect of the composition of flame retardant systems on the properties of viscose fibres

The possibility of modifying viscose fibre with hybrid systems containing flame retardants was demonstrated. The effect of the flame retardants on the physicomechanical properties of the fibres was determined. Bath compositions and modification parameters that ensure the sorption-diffusion reaction of the flame retardant and fibre and production of material with a high oxygen index (greater than 70%) were developed. Translated from Khimicheskie Volokna, No. 6, pp. 19–21, November–December, 2008.     

Surface energy of polyester and viscose fibres modified with polyfluoroalkyl acrylates

The comparative effectiveness of using polyfluoroalkyl acrylates of different structure to decrease the surface energy of viscose and polyester fibres was investigated. It was found that polyfluoroalkyl acrylates with a linear alkyl radical of optimum length (6–8 fluorinated atoms) were the most effective in decreasing the surface energy of viscose and polyester fibres; branching of the fluoroalkyl radical and appearance of oxygen atoms in the perfluorinated radical decreased the effectiveness of the modifier polymer. The index of the critical surface tension of heptane—oil mixtures was used as the criterion for evaluating the effectiveness of the polyfluoroalkyl acrylates in reducing the wettability of the fibre. The most effective modifier among the new polyfluoroalkyl acrylates was selected based on the results of the studies — polyperfluorodecyl acrylate. __________ Translated from Khimicheskie Volokna, No. 3, pp. 9–12, May–June, 2007.     

Change in the properties of polycaproamide fibres in treatment with metal complex salts

The modifying effect of chromium and aluminum salts on the properties of polyamide films was demonstrated. The possibility of increasing chemisorption of metal cations by polycaproamide fibres by treatment with UHF radiation was investigated. __________ Translated from Khimicheskie Volokna, No. 3, pp. 33–34, May–June, 2007.     

Thermal decomposition of polyester polyurethane and its elastomers exposed to γ-radiation

The thermal-decomposition parameters of unplasticized and nitrate ester plasticized polyester polyurethane elastomers with unsaturated carbon—carbon bonds in the initial state and after irradiation with doses of 120–380 kGy (γ-quanta ⁶⁰Co) were determined using dynamic thermogravimetry and differential scanning calorimetry. __________ Translated from Fizika Goreniya i Vzryva, Vol. 42, No. 2, pp. 133–138, March–April, 2006.     

Deformation of nonfired refractories based on phosphate binders. 6. Deformation under heating and creep in corundum composites

The results of studying heating deformation and creep are described for two systems: electrocorundum — α-Al₂O₃ — phosphate binder and electrocorundum — pyrophyllite — phosphate binder. It is shown that composites with H₃PO₄ experience less deformation than composites with the alumochromium-phosphate binder, whereas using pyrophyllite instead of aluminum oxide increases creep deformation due to the presence of the liquid phase in the material. The effect of technological factors is investigated. __________ Translated from Novye Ogneupory, No. 6, pp. 58–62, June, 2007. Continuation. See beginning in Vol. 48, Nos. 1–2, 2007.     

Plasma-solution modification of poly(ethylene terephthalate) fibre material

Plasma-chemical modification of polyester thread ensures formation of active hydroxyl and carboxyl groups on its surface, necessary for fixation of functional preparations whose application on the surface of fibre material gives it new properties — water-repellent, antimicrobial, deodorizing, etc. A comparison of the efficacy of plasma-chemical and chemical methods of surface activation of polyester fibre material shows that in the first case, greater losses of strength are observed in the thread. However, in the case of plasma-chemical activation, an additional number of carbonyl/carboxyl groups is formed, which is an important advantage in selecting the method of activating polyester materials.     

Study of the flame resistance of needle-punch heat-insulating material

The flame resistance of needle-punch material made from a blend of thermostable fibres was investigated. The dependence of the flame resistance on the process parameters of the needle-punch heat-insulating material was established. The maximum value of the oxygen index of 39% was attained at a punch density of 150 l/cm², punching depth of 10 mm, and polyester fibre content of 10%. Addition of low-combustibility polyester fibre in the blend allows reducing the cost of the raw material and price of the material, with good flame resistance of the finished material. __________ Translated from Khimicheskie Volokna, No. 3, pp. 48–49, May–June, 2007.     

Component triacylglycerols of six seed oils of malvaceae

The component triacylglycerols of six seed oils of the Malvaceae family—Gossypium barbadense (Egyptian cotton),Hibiscus cannabinus (kenaf),Hibiscus sabdarifa (roselle), two varieties ofHibiscus esculentas (okra) andAlthea rosea (ketmia, hollyhock or Egyptian hemp)—have been determined by using the lipase hydrolysis technique. The oils were found to contain triacylglycerols belonging to trisaturated (1.0–2.1), disaturated-monounsaturated (12.3–20.9), monosaturated-diunsaturated (42.3–46.6) and triunsaturated (30.1–44.2) types of triacylglycerols.     

Fabrication of New Water-Soluble Chitosan Derivatives

A new water-soluble derivative of chitosan — chitosan oligoethylene oxide sulfonate — was synthesized. The ratio and concentration of reacting substances and temperature and duration of the chitosan modification reaction affect the composition and properties of the reaction products. The conditions that ensure a 100% yield of water-soluble chitosan derivatives were determined. Using potentiometric titration and IR spectroscopy, the formation of a new water-soluble chitosan derivative — oligoethylene oxide sulfonate — was confirmed. __________ Translated from Khimicheskie Volokna, No. 4, pp. 41–44, July–August, 2005.