聚苯胺/苯乙烯-丁二烯-苯乙烯复合材料伸长过程中的导电性变化  

THE CHANGE OF CONDUCTIVITY DURING THE STRETCHING OF POLYANILINE/SBS COMPOSITES

作　　者：马永梅[1] 刘小武[1] 过俊石[1] 谢洪泉[1] 

机构地区：[1]华中理工大学化学系

出　　处：《高分子学报》1998年第1期14-20,共7页Acta Polymerica Sinica

摘　　要：以简化物理模型为基础，用实测电流与理论电流之比来研究导电橡胶伸长中电导率的变化，并建立相应测试方法．聚苯胺（ＰＡｎ）／苯乙烯丁二烯苯乙烯三嵌段共聚物的复合物用现场乳液聚合法制备．此复合物可熔融加工（ＭＰ）和溶液加工（ＳＰ）．ＳＳＰ样为ＳＰ样用间甲酚二次掺杂处理制得．对ＰＡｎ质量分数为１１０％的复合物进行电导率随伸长变化测试结果表明：ＭＰ样随伸长增加其电导率显著提高，在伸长率为４５０％时，其电导率是初始值（σ０）的１５６倍；ＳＰ样在伸长过程中电导率随伸长而增加，在伸长率为５００％时，其电导率是σ０的５２倍；而ＳＳＰ样在整个伸长过程中电导率变化较小，σ０＜σ＜２σ０．可从复合物的聚集态结构解释以上现象．ＳＳＰ样在导电组分的含量接近逾渗域值时电导率随伸长迅速下降．而当导电组分含量高于逾渗域值时电导率随伸长表现出小的变化并具规律性，此规律性可用σσ０＝１＋ｋａ＋ｂｋ２经验公式来表达（ａ，ｂ为与含量相关的常数）．Based on a simplification of physical model, the change of conductivity was studied by using the ratio of real current to theoretical current during the stretching of conductive rubber, and the relevant measurement was set up. The composite of polyaniline (PAn) and SBS was prepared by in situ emulsion polymerization technique, which can be processed by melt method (MP) or solution method(SP). The SSP sample was made by the treatment of SP sample with m cresol. The change of conductivity was measured during the stretching of the composites, of which the PAn content is 11.0%(wt). The results show that:(A) the conductivity of MP sample markedly increased with elongation, for example, the conductivity increased about 15.6 times at the elongation( k ) of 450%; (B) the conductivity of SP sample increased to 5.2 times at k equal to 500%;(C) For SSP sample the change of conductivity was relatively small, 1<conductivity ratio (σ K/σ 0)<2 in whole stretching process.These phenomena can be explained by the morphological structure of the composites,which was caused by the different processing methods. The conductivity of SSP sample showed two kinds of change trend. The conductivity noticeably decreased for the PAn content near the percolation thresheld, but the change of conductivity was small and regular for the PAn content higher than the percolation threshold. The empirical formula σ K/σ 0=1+k/(a+bk 2) was suggested to express the regularity. The result may be caused by a tenuous interconnected network of conductive component which was induced by secondary doping with m cresol.

关 键 词：导电橡胶 伸长 电导率 复合材料 PAN SBS 复合物 

分 类 号：TM242[一般工业技术—材料科学与工程] O631.23[电气工程—电工理论与新技术]