Alkaline hydrolysis and pretreatment of trilobal high dimethyl 5-sulfoisophthalate sodium cationic dyeable polyester

摘要

Lower glass transition temperature and crystallinity degree of trilobal high dimethyl 5-sulfoisophthalate sodium cationic dyeable polyester (THCDP) led to its more sensitivity to strong alkali and high temperature than regular Poly(ethylene terephthalate) (PET). The kinetic behaviors of alkaline hydrolysis of THCDP and PET were further explored, and the kinetics equations determined by regression analysis manifested that THCDP with high content of dimethyl 5-sulfoisophthalate sodium salt (SIP) was more prone to alkali hydrolysis and had higher weight loss rate. A comparatively lower power consumption pretreatment process of THCDP knitted fabrics benefited from the synergistic effect of various additives was applied in this study by response surface methodology and the optimum process with less auxiliaries, especially with less caustic treatment avoided large strength loss of fabric, as well as lower manufacturing cost in an environmentally friendly way.