Studies On Finishing Agent And Technics Of The Silk Fabric With Chitosan

Based on the remarkable performances of chitosan such as bacteria resistance, avirulence and bio-degradation, the preparation of finishing agent for silk fabric and its technical conditions were studied in this paper. Furthermore, the functional silk fabric were finished with the prepared finishing agent to obtain the good crease resistance and antibacterial properties in this study.Through analyzing the effects of the ratio of critic acid to tartaric acid on crease-resistance, whiteness and tensile strength of silk fabric, it was found that the optimal ratio of critic acid to tartaric acid is 1:1. Through the analysis of effects of dissolving temperature and time on viscosity and color of chitosan solution, chitosan with molecular weight of 496000 was chosen for dissolving at 60℃for 8h.Changes of wearability indexes of silk fabric before and after finished with chitosan and polycarboxylic acids were analyzed, and the results showed that crease-resistance of the finished silk fabric is improved significantly (increased by about 30o compared with the unfinished silk fabric); capillarity is improved slightly; whiteness and tensile strength are decreased slightly; draping property and handle get worse.Through comparing various domestic and foreign antibacterial testing methods, the proper testing method for silk fabric finished with chitosan was determined, and effects of molecular weight, degree of deacetylation and concentration of chitosan on antibacterial properties were analyzed in this study. Results showed that the molecular weight hardly had any effects on antibacterial performance, and the antibacterial properties are improved as the increase of concentration and degree of deacetylation. The antibacterial rate of Staphylococcus aureus exceeds 90% when the silk fabric was finished with chitosan with molecular weight of 496000 under concentration of 3%.To improve the handle of the finished silk fabric, organosilicon micro-emulsion was adopted as additives in chitosan finishing, and the optimal finishing technical conditions were obtained. Optimal finishing agents were presented as follows: concentration of chitosan is 2.8%; concentration of polycarboxylic acids is 12% (the ratio of critic acid to tartaric acid is 1:1); concentration of sodium hypophosphite is 5%; concentration of MEJ is 10%. Silk fabric bakes under 150℃for 120s will obtain the optimal effects. Results showed that through the application of micro-emulsion MEJ during the process of chitosan finishment, the crease-resistance of silk fabric is improved (increased by about 30o compared with the silk fabric just...