有机膨润土/水性聚氨酯复合涂层的制备与性能研究

Characterization & Preparation of Organically Modified Bentonite/Water-based Polyurethane Composite Coating

采用十六烷基三甲基溴化铵插层改性膨润土,并以有机膨润土、甲苯二异氰酸酯、聚己二酸乙二醇丙二醇酯等为基本原料,制备出有机膨润土/水性聚氨酯复合涂层。有机膨润土的加入,有效改善了水性聚氨酯的耐热性能、力学性能。TG-DSC分析显示加入有机膨润土后水性聚氨酯的熔点由266.8℃升高到290.9℃,表明加入膨润土提高了涂层的耐热性能。力学性能测试表明膨润土含量在5%时,其力学性能得到最大程度的改善,抗拉强度提高24.5%、抗撕裂伸长率提高40%。红外光谱分析显示异氰酸根和聚酯多元醇的羟基发生了反应。X射线衍射表明膨润土层间距由原来的1.5nm扩大至2.2nm,以及到聚合时的完全剥离。

Waterborne polyurethanes modified with organic bentonite are studied in this thesis .With the addition of organic bentonite in waterborne polyurethane, the heat resistance and mechanical properties are effectively improved. TG-DSC analysis shows that by adding organic bentonite to waterborn polyurethane,the melting point 266.8℃ rose to 290.9℃, it improves heat resistance of coatings. Mechanical properties have the greatest degree of improvement in tensile strength increased 24.5% and elongation at break-raising 40% when the organic bentonite are 5%. Infrared spectra shows that the -NCO and -OH are all reaction. X-ray diffraction shows that bentonite layer space is from 1.5 nm to 2.2 nm expansions, as well as to the complete stripping when polymerization.