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以改性介孔硅为主要补强剂,聚丙烯(PP)为基体树脂,环氧大豆油(ESO)为增塑剂和稳定剂,通过熔融挤出注塑方法制备了改性介孔硅-ESO/PP体系复合材料。通过XRD、SEM、光学显微镜(OM)、偏光显微镜(PLM)及力学性能测试对介孔硅与ESO增强增韧PP的机制进行分析。结果表明:改性介孔硅、ESO二者同时填充PP制备改性介孔硅-ESO/PP复合材料时,三者界面以物理交联或化学接枝的结合方式形成了空间网状结构,改性介孔硅均匀分散在PP基体中;改性介孔硅添加量一定时,随ESO用量增加,改性介孔硅-ESO/PP复合材料弯曲强度稍微下降,但抗冲击强度、硬度都得到提高,当改性介孔硅用量为20%(与PP的质量比)、ESO用量为2.5%(与PP的质量比)时,综合性能较好。改性介孔硅本身的高模量及粒子在聚合物熔体中的异向成核促进了基体树脂结晶,以及良好的界面结合及分散性,这是增强的主要原因。ESO分子插入聚合物分子链间,削弱了聚合物分子链间的移动性,一定程度降低了基体结晶度等是增韧的主要原因。改性介孔硅使α晶型PP转变为具有更高冲击强度β晶型PP,与ESO二者协同作用,能增强增韧,但是过多的ESO使介孔硅粒子集中在材料的表面,导致其表面硬度增大。
The modified mesoporous silica as the main reinforcing agent, polypropylene (PP) as the matrix resin and epoxy soybean oil (ESO) as the plasticizer and stabilizer were prepared by melt extrusion injection molding modified mesoporous silica - ESO / PP system composite materials. The mechanisms of mesoporous Si and ESO toughening PP were analyzed by XRD, SEM, OM, PLM and mechanical properties tests. The results show that when the modified mesoporous silica and ESO are both filled with PP to prepare the modified mesoporous silica-ESO / PP composites, the three interfaces form a spatial network structure by means of physical crosslinking or chemical grafting, The modified mesoporous silica was uniformly dispersed in the PP matrix. The flexural strength of the modified mesoporous silica-ESO / PP composite slightly decreased with the increase of the amount of ESO when the content of modified mesoporous silica was constant, but both the impact strength and the hardness The results showed that when the content of modified mesoporous silica is 20% (mass ratio to PP) and the amount of ESO is 2.5% (mass ratio to PP), the overall performance is better. The high modulus of the modified mesoporous silica itself and the heterogeneous nucleation of the particles in the polymer melt promote the crystallization of the matrix resin, as well as the good interfacial bonding and dispersibility, which is the main reason for the enhancement. The insertion of ESO molecules into the polymer chains weakens the mobility between polymer chains and reduces the degree of crystallinity of the matrix to a certain extent. Modified mesoporous silica to α crystalline PP into a higher impact strength β crystal PP, and ESO both synergistic effect, can enhance the toughening, but excessive ESO mesoporous silica particles concentrated in the surface of the material, Resulting in increased surface hardness.