SBS辐射接枝共聚研究III:星型SBS接枝改性

Study of styrene-butadiene-styrene graft copolymerization by γ-ray irradiation III:radiation graft of star SBS

利用γ射线辐射接枝法分别制备甲基丙烯酸(Methacrylicacid,MAA)和甲基丙烯酸酯(Methylmethacrylate,MMA)两种单体接枝星型SBS聚合物,采用傅立叶红外光谱(Fouriertransforminfrared,FT?IR)、差示扫描热分析(Differentailscanningcalorimetry,DSC)、热重分析(Thermogravimetricanalysis,TGA)、核磁共振谱(13C{1H}Nuclearmagneticresonance,NMR)等手段对接枝聚合物进行了表征,确定了单体成功地引入SBS链上,同时发现SBS接枝聚合物具有较好的高温稳定性。着重对敏化剂提高接枝率的原因进行了探讨,认为在液固相接枝体系中,溶剂水的辐解产物·OH自由基对接枝率的提高起了非常重要的作用。

The graft copolymerization of methacrylic acid （MAA）, methyl methacrylate （MMA） onto styrene-butadiene-styrene star triblock copolymer （SBS） was studied by ^60Co γ-ray irradiation. The graft yields increased with MAA or MMA concentration, and with l wt% CCl4 added to the grafting system. The structure of the graft copolymers was determined by Fourier-transform infrared （FT-IR） spectroscopy, differential scanning calorimetry （DSC）, thermogravimetric analysis （TGA）, and ^13C{^1H} nuclear magnetic resonance （NMR）. The results showed that hydroxyl radicals from, the irradiation product of water solvent, played an important role in improving the graft yield. It was found that decomposition temperature and the glass transition temperature of PS phase of the grafted polymer were improved, too. to a large extent. The study is of help to higher temperature applications of star SBS as a binder.