【作者】 陈广玲；

【导师】 杨杰；

【作者基本信息】 四川大学 ， 材料加工工程， 2006， 硕士

【摘要】 当前，对现有高分子材料进行改性以获得综合性能优良的聚合物新材料是高分子材料科学研究的重要课题之一。聚苯硫醚（PPS）作为第六大特种工程塑料，具有优良的热稳定性、良好的电绝缘性、耐腐蚀性和自阻燃性，已经广泛应用于汽车、电子电器和航空航天等各个领域。但纯PPS由于结构上的特点而具有一个突出的缺点——脆性大、冲击强度低，限制了其应用范围的进一步扩大。目前，研究者主要采用与其他聚合物共混制备合金以及添加纳米粒子的方法来提高PPS韧性。然而这些改性方法在提高PPS韧性的同时往往以牺牲PPS的优异性能来换取目标性能的提高，比如传统的弹性体在显著增韧的同时会给材料的强度、模量和热性能带来损失。虽然纳米粒子可以同时增韧增强聚合物，但是它对聚合物冲击性能的提高幅度有限。因此如何在保证材料具有良好的强度和热性能的同时，显著改善PPS的抗冲击性，成为PPS增韧改性研究领域努力追求的目标。 本论文在传统的弹性体增韧聚合物的基础上，选择带有支链和不饱和键结构的柔性聚合物LDPE与纳米SiO₂刚性粒子增韧增强PPS，并采用直接熔融共混、溶液包覆共混、溶液接枝共混和熔体（熔融）接枝共混四种方法制备复合材料。运用FTIR、SEM、DSC、PLM、TGA等测试手段，详细的研究了复合体系的力学性能与微观结构及其相互关系以及SiO₂／LDPE分散相的增韧增强机制。主要研究内容及结果如下： 1．首次采用LDPE熔融接枝改性SiO₂协同增韧增强PPS，材料的冲击强度被提高至85.1KJ/m²，是纯PPS的3.7倍；拉伸强度和弯曲强度分别提高27％和9％。SiO₂-LDPE包覆结构和包覆球中网络结构的形成、基体-包覆球界面的粘结粗更多还原

【Abstract】 At present, it has been an important object to obtain new polymer materials with excellent properties by means of modification of existing polymer materials. As the sixth high performance plastics, poly（phenylene sulfide） （PPS） has been widely used in auto, electronics industry and military field, due to its good combination of properties such as high thermal stability and electrical insulating ability, corrosion resistance and excellent self flame-retardance. But neat PPS has a deadly shortcoming of low impact strength, which limits the further use of it. Blending PPS with other plastics and filling with nanoparticles are most performed to improve the impact strength of PPS. However, conventional blending methods always decrease other properties while gaining the deserved ones. For example, elastomer can weaken the strength, modulus and thermal performances while improve the toughness significantly. Though nanoparticles can enforce and toughen the polymer simultaneously, it increases the toughness limitedly. How to obtain higher tensile or yield strength and thermal behavior as the impact strength increases has been an object hunted for by many PPS studiers on toughening modification.Based on the conventional elastomer toughening theory, thermoplastic low density polyethylene （LDPE） with branch chains and unsaturated double bonds was chosen as the toughening component. The LDPE together with rigid nano-SiO₂ particles is expected to have a synergistic toughening effect on PPS. The relationship between the mechanical performance and microstructure of composites was investigated by FTIR, SEM, DSC, PLM, et al. The toughening mechanism by SiO₂/LDPE composition dispersed phase was also explored and discussed. The main work and results obtained were listed as follows.1. For the first time, flexible LDPE and LDPE-melt-grafted nano-SiO₂ are used simultaneously to toughen and enforce brittle PPS. The impact strength of the composites was improved to 85.1KJ/m², which is 3.7 times of that of pure resin. The tensile and flexural strength was improved 27% and 9%, respectively. The formation of SiO₂-LDPE core-shell encapsulated structure and network structure with good interface adhesion in PPS matrix, and decrease of the size of spherilutes and crystallinity contributed the improvement of PPS.更多还原