链段间氢键化程度及离子基团对阴离子型聚氨酯性能的影响

以实验室自制的聚酯多元醇与甲苯二异氰酸酯(TDI)、一缩二乙二醇(DEG),通过聚合反应合成了结构相似的软段磺酸盐型聚氨酯分散体(SSSPU)、硬段磺酸盐型聚氨酯分散体(SHSPU)和硬段羧酸盐型聚氨酯分散体(CHSPU)。通过FT-IR、DSC、TG和力学性能测试,探讨了链段间氢键化程度和离子基团的种类及位置对聚氨酯胶膜性能的影响。结果显示:SSSPU的硬段之间有较强的氢键作用,呈现明显的微相分离结构,胶膜具有良好的力学性能和耐热性能;SHSPU的氢键作用弱,呈微相混合结构,胶膜力学性能差;CHSPU的氢键作用不仅存在于硬段之间,还存在于硬段与软段之间,呈微相混合结构,由于氢键及羧酸盐的离子缔合作用,其胶膜的力学性能最好。

Influence of Ionic Groups and Hydrogen Bonding Degree between Chain Segments on the Properties of Anionic Polyurethane

A series of polyurethanes, which have similar structures, bearing sulfonated soft segments (SSSPU), sulfonated hard segments (SHSPU) and carboxylated hard segments (CHSPU) are synthesized successfully by polymerization between polyester polyol, toluene diisocyanate (TDI) and diethylene glycol (DEG). Effects of hydrogen bonding degree between chain segments, the location and the type of ionic groups on properties of polyurethane (PU) film were studied via FT-IR, DSC, TG and mechanical property test. According to results, obvious micro-phase separation is observed in SSSPU film, as well as high mechanical property and heat resistance, resulting from strong hydrogen bond interaction between hard segments. On the contrary, the week hydrogen bond interaction in SHSPU film leads lower mechanical property and the formation of micro-phase mixing. Micro-phase mixing occured in CHSPU film is attributed to the hydrogen bond interaction forms not only between hard segments but also between hard segments and soft segments. In addition, hydrogen bond interaction and ion association of carboxylate also give CHSPU film the highest mechanical property.