大分子成核剂对PBA型水性聚氨酯结晶行为的影响

Effect of Macromolecular Nucleating Agent on Crystallization Behavior of PBA Waterborne Polyurethane

以聚己二酸1,4-丁二醇酯(PBA)、六亚甲基二异氰酸酯(HDI)、2,2-二羟甲基丙酸(DMPA)等为主要原料制备了数均分子量9 270的水性聚氨酯(WPU),将其作为大分子成核剂加入到PBA型水性聚氨酯(以PBA、HDI、异佛尔酮二异氰酸酯(IPDI)、DMPA等为主要原料制备,数均分子量28 700)中,研究了成核剂加入量对WPU结晶性能的影响。研究表明,大分子成核剂本身具有较高的热结晶温度,它的加入提高了WPU的热结晶温度、结晶速率和结晶度,增强了WPU胶膜的力学性能。当大分子成核剂乳液加入量为3 g即20%时,WPU中PBA热结晶温度为19.6℃,结晶度为47.7%,胶膜拉伸断裂强度为11.7 MPa。

Waterborne polyurethane(WPU)with a number-average molecular weight of 9270 was made via poly(1,4-butanediol adipate)(PBA),hexamethylene diisocyanate(HDI)and 2,2-dimethylolpropionic acid(DMPA).WPU was added to PBA aqueous polyurethane(Prepared with PBA,HDI,isophorone diisocyanate(IPDI),DMPA,etc.as the main raw materials,with a number-average molecular weight of 28700)as a macromolecular nucleating agent,and the effects of the amount of nucleating agent on the crystallization properties of WPU were studied.The results show that the macromolecular nucleating agent has a high thermal crystallization temperature,which increases the thermal crystallization temperature,crystallization rate and crystallinity of WPU,and enhances the mechanical properties of WPU film.When the mass fraction of macromolecular nucleating agent is 20%(3 g),the crystallization temperature of PBA in WPU is 19.6℃,the crystallinity is 47.7%,and the tensile fracture strength is 11.7 MPa.