NOPR Community:

Effect of hardness of water on degumming of silk

Sun, 01 Dec 1996 00:00:00 GMT

Title: Effect of hardness of water on degumming of silk Authors: Pathak, S; Prabhu, J; Somasekhar, T H Abstract: Degumming of silk was carried out in hard water and distilled water using different concentrations of an industrial grade detergent based on alpha olefin sulphonate. The optimum quantity of detergent was calculated and same was used for carrying out degumming with water having different levels of hardness. Degumming action has been found to be better in soft water. Correlation coefficient between degumming loss and hardness using this particular detergent has been found to be - 0.989. Degummed samples were tested for degumming loss, tenacity and elongation. It has been found that the optimum degumming loss is obtained with 1 gpl detergent in soft water. The tenacity increases with the decrease in hardness of water, whereas no clear trend is observed in case of elongation. Page(s): 283-285

Thermal behaviour of methyl methacrylate-grafted viscose fibres

Sun, 01 Dec 1996 00:00:00 GMT

Title: Thermal behaviour of methyl methacrylate-grafted viscose fibres Authors: Maji, Tarun Kumar; Khan, Ashis Kumar; Banerjee, Amarnath Abstract: Graft copolymerization of methyl methacrylate on viscose fibre has been done using titanium(III) chloride- potassium persulphate redox initiator under visible light in limited aqueous system in presence of various solvents and grafted polymers have been characterized by DSC and TGA. The DSC results show a low compatibility in the thermal properties of viscose fibre and PMMA. The role of pendant PMMA chain produced in presence of different solvents and the thermal stability of graft copolymers have been analyzed by TGA study. Page(s): 280-282

Abrasion resistance of modified polyester yarns

Sun, 01 Dec 1996 00:00:00 GMT

Title: Abrasion resistance of modified polyester yarns Authors: Rajendran, S; Ramasamy, S S; Mishra, S P Abstract: The abrasion behaviour of poly(ethylene terephthalate) based zero twist, high twist and spun yarns modified using trichloroacetic acid-methylene chloride (TCAMC) solvent system has been studied. The yarns were treated with different concentrations (1-5%) of TCAMC for 5 min at ambient temperature of 30°C. The problems associated with assessing the abrasion resistance are highlighted. The influence of elongation, initial modulus and plasticity on abrasion resistance is also discussed. At extreme treatment condition (5% TCAMC), the abrasion resistance of zero twist flat yarn increased to 4 times than that of the control, whereas no such improvement is observed in the other two yarns. Increase in elongation and plasticity and decrease in initial modulus help improve the abrasion resistance. Page(s): 276-279

Degumming of silk with different protease enzymes

Sun, 01 Dec 1996 00:00:00 GMT

Title: Degumming of silk with different protease enzymes Authors: Gulrajani, M L; Gupta, Shailja Vaidya; Gupta, Abhilasha; Suri, Mona Abstract: Silk was degummed with eight different commercially available enzymes, viz. Degummase 1000L, Protosol, Trypsin, Alcalase, Protease A, Protease N, Pepsin and Protease M. The degumming conditions with respect to concentration and time were optimised for each enzyme. Enzyme activity, an important intrinsic property, and degumming efficiency were evaluated in terms of weight loss, tensile strength, handle and lustre. A weight loss of 24±3% was observed for most of the enzymes at an optimum enzyme cone. of 15% except for Degummase 1000L which gave this result at 25% cone. Trypsin and pepsin gave extremely poor results. The increase in treatment time at the optimum enzyme cone. showed no further significant weight loss. There was no significant strength loss in any of the degummed samples but a marked improvement in handle and lustre was observed. SEM showed that Protosol enzyme gave the best results both with respect to weight loss and smoothness of the fabric. Page(s): 270-275