扩链剂对单组分阴离子型水性聚氨酯涂料性能的影响

以一缩二乙二醇(DEG)和DEG与4,4’-二羟基二苯基丙烷(BPA)的混合物分别为扩链剂,研究了扩链剂对单组分阴离子型水性聚氨酯(WBPU)乳液粒径、乳胶膜力学性能和吸水率的影响。结果表明:以DEG和BPA的混合物为扩链剂时制得的乳液平均粒径较大,分布宽;乳胶膜的拉伸强度高,延伸率小;乳胶膜的吸水率降低,且在浸泡48 h后已基本趋于饱和。制得WBPU乳胶膜试样的拉伸强度和延伸率分别为9.09 MPa、453%;酸、碱处理后的拉伸强度和延伸率分别为7.41 MPa、8.36 MPa和479%、429%。

Study on Influence of Chain Extender to Performance of One -Component Anionic Waterborne Polyurethane Coatings

In this article,diethylene glycol(DEG) and blend of diethylene glycol and bisphenol A(BPA) are used as the chain extenders,respectively to study its influence on particle size,mechanical properties and water absorption of one-component anionic(WBPU).The result shows: when the blend of DEG and BPA is used as chain extender,the average particle size is bigger and the distributing is wider;the tensile strength is stronger and the elongation at break is lower;the degree of water absorption reduced,and tends to be saturated over 48h.The tensile strength and the elongation at break of sample are 9.09 MPa and 453% respectively;7.41 MPa?8.36 MPa and 479%?429%,when treated with and become acid and base respectively.