烷基化改性聚对苯撑

Modification of Polyparaphenylene by Alkylation

通过亲电取代反应在聚对苯撑(PPP)的苯环单元上引入异戊基,并用烷基化聚对苯撑与聚氨酯(PU)共混制备了共混材料。实验证明烷基化聚对苯撑能溶于氯仿。比较改性前后共混材料的拉伸性能,含有改性聚苯撑共混材料的拉伸强度和断裂伸长率比未经改性的聚苯撑共混材料分别高30.4%和41.6%,说明两相相容性提高。并用扫描电镜(SEM)观测改性前后的PPP/PU共混材料,发现含有改性聚苯撑的共混材料的形态结构发生了变化,两相界面变得模糊,这进一步证实两相部分相容,界面存在一定的粘合力。

In order to obtain a polyparaphenylene that is soluble in organic solvents and compatible with other macromolecules, isoamyl polyparaphenylene ＇is prepared by electrophilic substitution reaction under Friedel-Crafts conditions. It is discovered from the experiments that the alkylated polyphenylene dissolves in chloroform. IR, NMR and elemental analyses are used to characterize the structure of alkylated-PPP. Two blend materials are prepared by blending polyurethane with modified polyphenylene or non-modified polyphenylene. Tensile tests show that the tensile strength and elongation at break of the modified polyphenylene are 30.4%, 41.6% highter than that of the non-modified one respectively. SEM reveals that the dispersion of modified polyphenylene in the polyurethane is more homogeneous than nonmodified one, and the interface between polyphenylene and polyurethane becomes blurred, which indicates the two phases are compatible to a certain extent.