环状聚烯烃的共混增韧改性

Blending Toughening Modification of Cyclic Olefin Polymers

环烯烃聚合物(COP)由于具有较高的透明度、耐热性能、耐溶剂性和较低吸水率等特点,在光学和医疗领域中得到广泛应用,但是,需要改善其韧性。以聚烯烃弹性体(POE)为增韧剂、马来酸酐接枝(苯乙烯/乙烯/丁烯/苯乙烯)共聚物(SEBS-g-MAH)为增容剂,采用双螺杆熔融共混制备了COP/POE共混物,重点研究了POE含量对共混物形态、流变行为和力学性能的影响。研究结果表明,COP/POE共混物呈两相结构,随着POE含量的增加,复合材料从颗粒状分散相向双连续相形态转变,SEBS-g-MAH对提高共混物的两相粘接力具有一定的促进作用;另外,随着POE含量的增加,COP/POE共混物的拉伸强度逐渐降低,断裂伸长率由8%提高到20%以上,与COP相比,冲击强度提高了6.4倍,由4.8 kJ/m^(2)提高到30.8 kJ/m^(2)。

Cyclic olefin polymers(COP)had shown promising applications in the fields of optics and medical due to their high transparency,high heat resistance,solvent resistance and low water absorption.However,their toughness needs to be further improved.The COP/POE blends were prepared by using Polyolefin elastomer(POE)as a toughening agent,maleic anhydride grafted(styrene/ethylene/butene/styrene)copolymer(SEBS-g-MAH)as a compatibilizer through twin-screw melt blending method.The effects of POE content on the morphology,rheological behavior and mechanical properties of the blends were investigated.The results showed that the COP/POE blends exhibited a two-phase structure,and with the increase of POE content,there was a morphological transformation from a granular dispersed phase to a bicontinuous phase.SEBS-g-MAH showed a certain promoting effect on improving the two-phase adhesion of the blends.As the POE content was increased,the tensile strength of COP/POE blend gradually decreased,the elongation at break increased from about 8%to over 20%,and the impact strength increased by 6.4 times from 4.8 kJ/m^(2)to 30.8 kJ/m^(2).