PMMA/SMA共混体系流变行为与温度依赖性的研究

Study on Dependence of Rheological Behavior of PMMA/SMA Blends on Temperature

研究了甲基丙烯酸甲酯/苯乙烯马来酸酐共聚物(PMMA/SMA)体系的流变行为,探讨了SMA中马来酸酐(MA)含量对于共混体系时温叠加和温度依赖性的影响。结果表明,MA含量为12%(质量分数,下同)的PMMA/SMA12体系符合时温叠加原理,在低温下松弛时间与组分的关系存在正偏差,随温度上升浓度涨落加剧而有负偏差的情况出现;MA含量为28%的PMMA/SMA28体系时温叠加原理由于动力学不对称性而失效,在低温区域松弛时间与组分符合对数线性关系,高温区域则出现正偏差;与PMMA/SMA12相比,PMMA/SMA28具有更强的温度依赖性。

The rheological behavior of poly （methyl methacrylate）/styrene maleic anhydride copolymer（PMMA/SMA） was investigated, where the effects of content of maleic anhydride（MA） on the time-temperature superposition （TTS） and the temperature dependency in PMMA/SMA were discussed. It indicated that for PMMA/SMA12 with 12% MA in SMA, TTS was valid and there were positive deviations in the log-linear relation between relaxation time and composition at lower temperature, while the positive deviation became weaker with the rising of temperature and negative deviation occurred in some compositions. For PMMA/SMA28, TTS failed due to the dynamic asymmetry, where the relaxation time and the composition followed a log-linear relation at lower temperature while positive deviation occurred at higher temperature.