异氰酸酯功能化石墨烯/水性聚氨酯复合材料的制备及性能研究

Preparation and Properties of Isocyanate Functionalized Graphene/Waterborne Polyurethane Composites

为提高水性聚氨酯(WPU)机械及防腐等性能,首先以4,4′-二环己基甲烷二异氰酸酯(HMDI)对氧化石墨烯(GO)表面进行化学改性,得到一种异氰酸酯功能化石墨烯(iGO)。后又通过原位聚合制备异氰酸酯功能化石墨烯/水性聚氨酯复合乳液,并将复合乳液制为薄膜和涂层。通过红外光谱仪、热分析仪、万能试验机和电化学工作站等对iGO和复合薄膜、涂层表征测试。结果表明,iGO表面成功接枝了HMDI;相较于WPU薄膜,复合薄膜接触角增大约20°,拉伸强度和断裂伸长率最大提高约60.57%和40.36%;复合涂层对基体的保护效率达到99.96%,相较于WPU涂层提高了18.52%。

In order to improve the mechanical and anti-corrosion properties of waterborne polyurethane(WPU),the surface of graphene oxide(GO)was chemically modified with 4,4′-dicyclohexylmethane diisocyanate(HMDI)to obtain an isocyanate functionalized graphene(iGO).Then the isocyanate functionalized graphene/water polyurethane composite emulsions was prepared by in-situ polymerization.And the composite emulsions was made into films and coatings.Infrared spectrometer,thermal analyzer,universal testing machine and electrochemical workstation were used to characterize and test iGO,composite films and coatings.The results show that the surface of iGO is successfully grafted with HMDI.Comparing with WPU film,the contact angle of the composite films increases about 20°.The maximum increase in tensile strength and elongation at break is about 60.57%and 40.36%.The protection efficiency of the composite coating on the substrate could reach 99.96%,which has increased 18.52%comparing with the WPU coating.