环氧改性醇溶性聚氨酯分散液的制备及成膜性能

Synthesis and properties of polyurethane alcohol dispersion modified by epoxy resin and its membranes

以二月桂酸二丁基锡（T-12）为催化剂,通过异佛尔酮二异氰酸酯（IPDI）,聚四氢呋喃二醇（PTMG1000）,二羟甲基丁酸（DMBA）、γ-氨丙基三乙氧基硅烷（γ-APTES）和环氧树脂（E-44）的反应制备了醇溶性羟基封端聚氨酯（EPPU）.采用傅立叶变换红外光谱（FT-IR）、X 射线衍射（XRD）、透射电镜（TEM）和扫描电镜（SEM）对聚氨酯的结构进行了表征,并测试了环氧树脂含量w （E-44）对胶膜的耐热性、力学性能和耐水性的影响.FT-IR测试结果表明环氧树脂与聚氨酯发生了反应,实现了化学改性.环氧改性使聚氨酯的结晶度下降,同时热稳定性和机械性能得到改善.当w （E-44）从0%（质量分数）提高到10% （质量分数）,改性使聚氨酯的拉伸强度从5.19-6.99MPa,吸水率从19.81%降低至4.865%.

Hydroxyl-terminated polyurethane modified by epoxy resin( EPPU) was prepared by the reaction of isophorone diisocyanate( IPDI),poly( tetramethylene glycol)( PTMG),2,2-dimethylolbutanoic acid( DMBA),γ-Aminopropyl triethoxysilane( γ-APTES),phoenix epoxy resin( E-44) and dibutyltindilaurate( T-12) as catalyst. The structure of the polyurethane was characterized by Fourier transform infrared( FT-IR) spectrometer,X-ray diffraction( XRD) and transmission electron microscope( TEM). The effect of E-44 content on thermal stability,mechanical properties and water absorption of the membranes were measured. FT-IR indicates that epoxy resin has been successfully introduced into the polymer main chain,and XRD shows that crystallinity of EPPU decreased with the addition of epoxy resin while the thermal stability has been improved. It was found that better mechanical properties of polyurethane were obtained when chemical networks formed after modification by epoxy resin. As the w( E-44) increases from 0% to 10%,the tensile strength increased from 5. 19 to 6. 99 MPa and the water absorption of the membranes decreased from 19. 81% to 4. 865%.