过氧化二异丙苯和酚醛树脂对HDPE/GTR共混物的原位反应性增容

采用过氧化二异丙苯(DCP)和热塑性酚醛树脂(HY-2045)在未添加催化剂时实现了对高密度聚乙烯(HDPE)/废旧轮胎胶粉(GTR)共混物的原位反应性增容, 并研究了其对共混物的微观形貌、 应力-应变曲线、 动态力学性能和结晶性能的影响. 扫描电镜结果显示, 共混物橡塑界面处有大量的纤维状物质同时嵌入到基体相和分散相中, 使得共混物的界面强度得到显著增加, 从而获得较好的综合力学性能. 差式扫描热量(DSC)和X射线衍射(XRD)测试结果表明, 原位增容后的共混物的结晶度显著降低, 致使其明显的拉伸屈服现象消失. 由于反应型增容剂DCP和HY-2045使得共混物在界面处形成化学交联, 尽管其结晶度有所降低, 但是其拉伸强度和断裂伸长率还是得到了显著的增加. 另外, 动态力学性能测试表明, 增容后的HDPE/GTR共混物中GTR相的玻璃化转变峰变宽, 玻璃化转变温度升高.

In-situ reactive compatibilization of HDPE/GTR blends by dicumyl peroxide and phenolic resin without catalyst

In-situ reactive compatibilization of high-density polyethylene (HDPE)/ground tire rubber (GTR) blends by dicumyl peroxide (DCP) and HY-2045-a kind of thermoplastic phenolic resin without catalyst was investigated by studying the morphology, stress and strain behavior, dynamic mechanical properties and crystallization performance of the blends.Scanning electron microscopy (SEM) results show that there are a lot of fibrous materials distributing in the interface, which connects the dispersed phase with the matrix and obtains better interfacial strength for prominent mechanical properties.The addition of compatibilizers results in the decrease of crystallinity of the blends and the disappearance of an obvious yield phenomenon, which was proved by the differential scanning calorimeter (DSC) test and X-ray diffraction (XRD) characterization.Although the crystallinity of the blends decreases, the tensile strength and tensile strain of the blends significantly increases, especially for the HDPE/GTR/DCP/HY-2045 blends, which is possibly attributed to the good compatibility of the blends owing to the in-situ interface crosslinking.In addition, it is found that the compatibilizing HDPE/GTR blends shows a higher tanδ peak temperature and a broaden transition peak for GTR phase.