聚苯乙烯-聚硅氧烷接枝共聚物的合成与表征

Synthesis and characterization of polystyrene-g-polydimethylsiloxane copolymers

以甲基丙烯酰氧丙基聚硅氧烷大单体(PDMS-MA)与苯乙烯共聚合,制备了聚苯乙烯聚硅氧烷梳状接枝共聚物(PSt-g-PDMS),采用傅里叶变换红外光谱(FTIR)表征了接枝共聚物的组成,研究了聚硅氧烷大单体的相对分子质量对共聚合活性的影响,并对接枝共聚物的热性能进行了表征.结果表明,大单体PDMS-MA的共聚合活性随其相对分子质量的增大而减小,随投料比的增加,共聚合转化率下降.与纯聚苯乙烯相比,PSt-g-PDMS的热稳定性提高.而且,随着大单体PDMS-MA相对分子质量和它在共聚物中含量的增加,接枝共聚物的热稳定性增加.

Polystyrene-g-polydimethylsiloxane copolymers were prepared by using the methacryloxypropyl-polysiloxane (PDMS-MA) macromonomer technique. The structures of graft copolymers were characterized by Fourier transform infrared (FTIR) spectroscopy. The influence of molecular mass of PDMS-MA on copolymerization activity was investigated. Thermal properties of the graft copolymer were also studied. The reactivity of PDMS-MA decreased with increasing molecular mass. Meanwhile with increasing ratio of PDMS-MA to styrene, the copolymerization conversion of PDMS-MA decreased. The heat-resistance of PSt-g-PDMS was improved comparing to PSt alone. The improvement was greater when the molecular mass of PDMS-MA and its contents were increased.