软段对水性聚氨酯结构与性能的影响

以低聚物多元醇、异氟尔酮二异氰酸酯(IPDI)、亲水单体二羟甲基丙酸(DMPA)，乙二胺为主要原料，制备了一组不同组成的聚氨酯乳液。通过粘度测定、粒度分析、力学性能和耐水性能测试、原子力显微镜(AFM)分析，研究了软段类型、软段分子量对乳液及其胶膜性能的影响。结果表明，分子结构规整、易结晶的软段合成的聚氨酯树脂力学性能和耐水性能都较好，对聚己二酸酯而言，分子量减小，其合成的水性聚氨酯拉伸强度提高，耐水性能却有很大程度的下降。

Effects of Soft-Segments on the Structure and Properties of Polyurethane Emulsion

Ionomer-type polyurethane emulsion was prepared from pelyether or polyester , IPDI, dimethylol propionic acid (DMPA) and ethylene diamine as primary materials. The emulsion characteristics and properties of PU films were studied by means of rotational viscosimeter,Autosizer ,tensile tester and atomic force microscope (AFM). The effects made by the type of soft-segments and the different M_n of soft-segmente on the performance of the emulsion and film were also discussed. The results show that when the soft-sesment have ordered molecular structure and crystallization tendency ,the PU resin have hatter mechanical properties and water resistance properties, when the soft-segment is CMA,the reduction of M_n of soft-segment contribute to the increasing of mechanical strengths and the decreasing of water-resistance property of PU.