【作者】 台会文；

【导师】 金日光； 张留成；

【作者基本信息】 北京化工大学 ， 材料学， 1998， 博士

【摘要】 探索高分子合金的组成、结构与性能之间的关系是开发新型共混合金材料的关键。为了研制高韧性PBT共混合金材料并揭示共混合金材料的结构-性能之间的关系，本文采用双螺杆挤出机的制备了一系列PBT共混物，包括：PBT／POE、PBT／EVA、PBT／ABS、PBT／EPDM、PBT／SEBS、PBT／MBS、PBT／MAS等；研究了这些合金材料的冲击强度、拉伸强度、热性能及形态结构，总结了组成-结构-性能之间的关系；通过大量的实验，最后通过原位反应挤出得到了一种高强高韧PBT合金材料。通过固相接枝制备了马来酸酐接枝的超高分子量聚乙烯，并将其与上面得到的PBT／POE及PBT／MBS／Epoxy共混来改进材料的应用性能。 将环氧树脂用作PBT／MBS或PBT／MAS共混体系的反应增容剂，并使材料性能得到大幅度提高。通过在双螺杆挤出过程中环氧树脂与PBT反应原位生成嵌段共聚物或接枝物，使PBT与MBS之间的相界面得到加强，材料的拉伸强度、断裂伸长率，特别是材料的冲击强度得到大幅度提高。 在对PBT／MBS(MAS)／Epoxy共混合金体系进行结晶动力学研究中，研究了MBS及环氧树脂对合金材料结晶性能的影响，并反过来由结晶动力学数据来表征增容剂环氧树脂的作用机理。特别是应用第四统计力学理论研究结晶动力学，揭示了增容剂对体系结晶性影响的实质。采用毛细管流变仪测试了PBT／MBS(MAS)／Epoxy共混合金体系的流变性能。通过对体系流变学的研究，得出冲击改性剂及增容剂对体系流变性能的影响。同时流变学的研究也为确定共混物处于熔融态时结构提供了证据。采用透射电镜及扫描电镜观察PBT／MBS合金体系表明，具有核壳结构的冲击改性剂MBS在体系中的中加入环氧树脂可以形成串珠状结构，因而认为环氧树脂一方面通过提高PBT／MBS相界面粘结力，另一方面由于MBS粒子之间粘合力增加，在剪切场下MBS形成串珠状结构，而使材料的性能得到提高。 通过对合金材料性能的变化规律以及材料的冲击强度与冲击断口的对比分析，首次从增韧合金材料的冲击断裂动力学角度及基体本身的形变能力及影响形变能力的因素出发，在理论上提出了“延时大形变”增韧机理，总结了影响材料韧性的八种因素。 研究了结晶动力学的群子参数与共混合金力学性能之间的关系，并首次在理论上从材料的结晶群子参数分析了增韧剂及相容剂对材料的性能的影响，建立了结晶性共混合金材料的结晶群子参数与材料力学性能之间的关系。更多还原

【Abstract】 Modern industry demands increaingly new materials with excellent properties. As a method to develop new polymeric materials, blending is no less important to modify their microstructures and thereby end-use properties. Superior properties can result through the combination of very different materials in polymer blends and composites. The correlation between properties and structure of polymer blends is more than critical for us to develop new blends with improved properties.PBT is an important engineering plastic, which has many merits but is fragile. So toughening for PBT has attracted great interesting of scientists In this thesis a wide range of PBT blends included PBT/POE, PBT/EVA, PBT/SEBS, PBT/ABS, PBT/EPDM, PBT/MBS (or MAS) was prepared through twin screw extruder. PBT/POE and PBT/EPDM blends were compatibilized by MAH through in-situ reactive extrusion. The compatibilizing effects of an epoxy resin (LER-2050) on the blend of PBT and MBS (methyl methacrylate-butadiene-styrene copolymer) or MAS (methyl methacrylate-butyl acrylate-styrene copolymer) core-shell impact modifiers were investigated. PBT/MBS (MAS)/Epoxy blends were also prepared by in-situ reactive extrusion. The rheology, crystallization kinetics, impact strength, morphology, and mechanical behavior of blends prepared above were researched. The research on PBT/Elastomer/UHMWPE blends explored PBT blends for self-lubricant materials, which can be used in bearings and slipping materials.Experimental facts showed that different blend systems express different mechanisms in the correlation between the property and the composition for their difference in compatibility. ABS, MBS and MAS are good impact modifier for PBT. Compatibilization is efficient to improve the properties of PBT blend.We have looked at how the various properties of Poly (butylene terephthalate) (PBT) and MBS (or MAS) blends are affected by the addition of an epoxy resin. The impact strength of the ternary blend increased dramatically with the addition of 1% Epoxy resin to the PBT/MBS blend, and supertough PBT alloy was obtained. Further addition of epoxy resin decreased the impact strength. At this point (1% Epoxy resin), the tensile strength and the ultimate elongation of the PBT80/MBS20/Epoxy blends with various更多还原