环氧交联改性水性聚氨酯的结构及其性能研究

Structure and Properties of Waterborne Polyurethane Emulsion Modified by Epoxy Resin as Crosslinker

合成了一系列环氧树脂(E-44)交联改性自乳化聚氨酯乳液。通过FT-IR、TG对聚合物结构和热性能进行了研究,通过透射电子显微镜(TEM)观察乳液形貌。分析了w(E-44)及聚醚二醇(PTMG)相对分子质量对聚氨酯力学性能的影响,并测试了改性聚氨酯膜的耐溶剂性。FT-IR分析表明:环氧树脂的羟基和环氧基都参与了发应。TEM表明:乳液颗粒呈均匀分散的刚性球状。TG分析表明:E-44的加入可以提高聚氨酯的热稳定性。随着w(E-44)增大,改性聚氨酯膜的拉伸强度增大,断裂伸长率减小,吸水率和吸乙醇率减小。

A series of waterborne polyurethane emulsion modified by epoxy resin were prepared with epoxy resin（E -44） as erosslinker. Fourier transform infrared spectroscopy（FT - IR）, thermogravimetry （TG） and transmission electron microscope （TEM） were used to characterizer the structure of the polyurethane and particle morphology of the resultant dispersions. The effect of Mw of E -44 resin and PTMG on the mechanical property and solvent resistance of the cast films were tested. FT -IR indicated that both epoxy group and hydroxyl group of E -44 were reacted with polyurethane prepolymer. TEM showed that the morphology of dispersion particle was sphericity. TG indicated that the crosslink of E -44 with polyurethane increased thermal stability of the modified polyurethane. It was found that the tensile strength of films of PU increased and the elongation at break, water absorption and ethanol absorption decreased with increasing of w（E- 44）.