纳米OMMT／EVA-g-PU复合材料

Nano-OMMT/EVAgPU composites

采用熔融接枝与熔融插层相结合的方法,成功制备了纳米OMMT/EVA-g-PU复合材料。通过FTIR及13C NMR测试表明,端—NCO的聚氨酯(PU)预聚体与皂化乙烯-醋酸乙烯酯共聚物(EVA)间发生接枝反应。采用X射线衍射仪(XRD)与透射电镜(TEM)观察了蒙脱土(OMMT)在基体中的分散状态,用电子万能试验机、动态力学分析仪(DMA)和热重分析仪(TG)分析了复合材料的力学性能、储能模量和热性能。结果表明:OMMT主要以插层型分布在基体中;当OMMT的质量分数为3%时,复合材料的断裂强度、杨氏模量和撕裂强度分别为7.96 MPa、7.12 MPa和49.97 MPa;复合材料的储能模量随OMMT含量的增加而升高,当OMMT的质量分数为7%时,复合材料的储能模量相对于纯EVA提高了2倍多;复合材料的热稳定性能也要优于纯EVA,并随OMMT含量的增加而升高。

OMMT/EVA - g - PU nanocomposites were prepared through the method of melting graft and melting intercalation. The characterization of FTIR and ^13C -NMR indicates that -NCO terminated polyether-polyurethane prepolymer is grafted on the EVAL main chain successfully. The dispersion state of OMMT in matrix was observed by XRD and TEM. The mechanical properties and storage modulus and thermal stability were studied by the microcomputer-controlled electronic tensile tester and DMA and TG. The results indicate that the chief dispersion state of OMMT in EVA - g - PU matrix is intercalated. When the mass fraction of OMMT is 3%, the tensile strength, Young＇s modulus and tear strength are 7.96 MPa, 7.12 MPa and 49.97 MPa, respectively. The storage modulus of nanocomposites increase with the increase of OMMT amount. When the mass fraction of OMMT is 7% , the storage modulus of nanocomposites is 2 times than that of pure EVA. The thermal stability of OMMT/EVA - g - PU nanocomposites is far superior to that of pure EVA with the increase of OMMT amount.