聚乙烯/膨胀石墨复合材料的结构和导电行为

Structure and Electrical Conductive Behavior of PE/Expanded Graphite Composite

研究了用溶液混合 (SM)和熔融混合 (MM )法制备的PE/gPE/EG (m [gPE] /m [EG] =3 /2 )复合材料的交、直流导电行为及其与结构形态的关系。结果表明 :与MM法制备的复合材料相比 ,SM法制备的复合材料的逾渗阈值 (wc)降低一半以上 ,在膨胀石墨 (EG)质量分数 (wEG)接近wc 的情况下 ,交流伏 -安特性的非线性指数减小 ,直流电阻 -温度特性的PTC强度也明显降低 ;

PE/maleic anhydride grafted PE (gPE)/expanded graphite(EG) (gPE/EG=3/2 w/w) composites were prepared via solution mixing (SM) and melt mixing (MM),and the d.c.and a.c.conducting behavior of the composites was studied in assosiation with their structure and morphology.The results showed that the percolation threshold (w) of the SM composites was a half less than that of the MM composites,and in case of EG weight fraction (f w) closed to the f w,c,the non-linear exponent of a.c.volt-ampare characteristics and the PTC intensity of d.c.resistivity-temperature characteristics of the SM-composites were much lower than those of the MM-composites,which could be explained by the differences of the structure and morphology of the composites.