TPU/EVM共混体系的动态硫化工艺

比较了通过HAAKE Rheocord90转矩流变仪用两种不同的动态硫化混炼方法对热塑性聚氨酯弹性体/乙烯-醋酸乙烯酯共聚物(TPU/EVM)共混体系性能的影响,硫化剂选用过氧化二异丙苯(DCP);探讨了密炼室转子转速和混炼温度对动态硫化共混物性能的影响。通过相差显微镜和傅立叶变换红外光谱仪(FT-IR)对硫化后共混物的微观结构进一步分析表明:动态硫化后的共混体系力学性能优于未硫化体系;两种不同动态硫化法制备的共混物性能相比,B法优于A法,且B法中两相呈明显互锁结构,相畴较小且均匀;FT-IR表明EVM主链的亚甲基和侧链的甲基参与了交联反应,且主要在亚甲基上;转速为30 r/min和混炼温度为150℃时共混物的综合力学性能最优。

Preparation Technology of Dynamic Vulcanized TPU/EVM Blends

Two methods of different dynamic vulcanization processing of TPU/EVM blends in HAAKE Rheocord90 were compared in which DCP was chosen as the curing agent.The Phase contrast microscope and FT-IR were used for analysis of blends structure.The effect of rotor speed and mixing temperature were also studied.The result shows that: the mechanical property of the vulcanized blend is better than that of uncured blend.The mechanical property of TPU/EVM blend prepared by B processing method is better than that of prepared by A method.The phase in blend made by B method is smaller and more symmetrical.It is suggested from FT-IR that the cross linking active point in the EVM copolymers occurs both in the methylene of the backbone chain and in the methyl group of the side chain and more crosslink emerged on methylene.The rotor speed and mixing temperature for best mechanical properties of blend in Haake are 30 r/min and 150 ℃.