动态硫化法PP/EPDM/纳米SiO_2双重粒子协同增韧改性研究

Study on the cooperative toughening of dynamic vulcanized PP/EPDM/nano-SiO_2 composites with double particles

以三元乙丙橡胶 (EPDM)作弹性粒子 ,以纳米SiO2 作刚性粒子 ,通过动态硫化方法制备了PP/EPDM/纳米SiO2 三元改性材料 ,并采用力学性能测试、动态力学试验、DSC分析和偏光显微镜观察等方法 ,研究了该材料的结构与性能。结果表明 ,纳米SiO2 与EPDM对PP具有协同增韧和增强效应 ,这种效应与 2种粒子的浓度比相关 ,当纳米SiO2 质量分数为 3 %、EPDM质量分数为 1 0 %时 ,协同作用最明显。 2种粒子使PP出现较大的低温损耗模量峰 (E″)和内耗峰 (tanδ) ,并具有成核作用 ,使PP结晶温度提高 ,结晶速率加快 ,形成的球晶细小而均匀 ,并同时提高结晶度和熔点。

PP/EPDM/nano-SiO 2 modified composites with elastic particles of EPD M and rigid particles of nano-meter SiO 2 were prepared by dynamic vulcanizat ion.The structure and the properties of the composites were studied with mechanical property test,dynamic mechanical test,differential scanning calo rimetry(DSC) and polarizing microscope.The results show that the rigid particles of nano-SiO 2 and the elastic particles of EPDM make cooperative toughening and reinforcing effect on PP.The effect is correlated with the concentration ratio of two particles.When the content of nano-SiO 2 is 3%(wt) and the conte nt of EPDM is 10%(wt),the cooperative toughening and reinforcing effect is the m ost evident.Two particles make PP higher loss modulus (E″) and mechanical lo ss(tanδ) at l ow temperature.Two particles have nucleating function,so as to raise the crystal l ization temperature,expedite the crystallization rate,form the finer and equaler spherulite structure,and increase the degree of crystallinity and the melt poin t of PP.