内交联水性聚氨酯涂膜性能的影响因素

Influence Factors of the Performance of Crosslinked Waterborne Polyurethane

以异氟尔酮二异氰酸酯、1,6-己二异氰酸酯、二羟甲基丙酸、聚氧化丙烯二醇和聚己二酸-1,4丁二醇酯为原料,合成了一系列内交联水性聚氨酯分散体(WPU)。研究了NCO/OH物质的量比和内交联剂三羟甲基丙烷(TMP)用量对水性聚氨酯涂膜性能的影响,并通过红外光谱(FT-IR)、接触角测量、热重分析(TGA)和X射线衍射(XRD)等对涂膜性能进行了表征。实验结果表明,NCO/OH物质的量比和TMP含量的增加均会使涂膜拉伸强度增加。XRD分析表明,软段微区的结晶性能随着二羟甲基丙酸(DMPA)含量的增加而减小,当DMPA的质量分数增加至5.6%时,软段微区表现出非晶态。

A series of crosslinked waterborne polyurethane（WPU） were prepared through a prepolymer process using isophorone diisocyanate,hexamethylene diisocyanate,dimethylol propionic acid,propylene glycoland polybutylene adipate as raw materials.The effects of NCO/OH mole ratio and trimethylolpropane（TMP） content on the properties of waterborne polyurethane films were studied.The properties of the WPU films were characterized by FT-IR,contact angle measuring instrument,thermogravimetric analysis（TGA） and X-ray diffraction（XRD）.The results show that the tensile strength increases with the increase of NCO/OH mole ratio and TMP content.The water resistance and mechanical properties are greatly improved with the increase of TMP content.The XRD analysis shows that the crystallization in soft regions disappears when w（DMPA） is higher than 5.1%,and the soft segment crystallinity decreases with DMPA content increasing.