【摘要】 研究了室温下苯乙烯-丁二烯-苯乙烯(Styrene-Butadiene-Styrene,SBS)在60Coγ射线下的辐照效应。采用傅立叶红外光谱(Fourier-transform infrared spectroscopy,FT-IR)、差示扫描分析(Differential scanning calorimetry,DSC)、热重分析(Thermal gravimetric analysis,TG)、扫描电镜(Scanning electron microscopy, SEM)、动态剪切流变(Dynamic shear rheology,DSR)等分析方法对辐照产物进行了表征。辐照产物经红外光谱分析,未发现有氧化物生成;SBS辐照后发生交联反应,随着吸收剂量的升高,不溶于甲苯的交联SBS 量增加;DSC和TG表明辐照后材料的柔性聚丁二烯嵌段和刚性聚苯乙烯嵌段的玻璃化温度向高温方向移动, 同时有更高的玻璃化温度点形成,耐高温物质量增加;动态剪切流变分析表明辐照后出现新的网络松弛行为, 吸收剂量越高,材料的损耗因子峰越明显;辐照后SBS剪切粘度变大,储能模量增加,损耗模量下降,材料的温度敏感性下降;扫描电镜分析表明SBS辐照后抗氧化性能也得到了提高。更多还原

【Abstract】 The effect of SBS irradiated with 60Co γ-rays at ambient temperature was studied in this article. SBS before and after irradiation were characterized by means of Fourier-transform infrared spectroscopy(FT-IR), differential scanning calorimetty (DSC), thermal gravimetric analysis(TG), scanning electron microscopy(SEM), and dynamic shear rheology(DSR). Almost no oxidation substance product was found in FT-IR spectra of the irradiated SBS. Cross-linking reaction occurred after SBS irradiation, and with increasing doses, the mass ratio of indiscerptible content in toluene developed. The analysises of DSC and TA indicated that Tg of the flexible segment PB and rigid part PS shifted to a high temperature to some extent. A higher Tg of about 120℃ came into being and the substance of resisting high temperature increased. According to DSR analysis, a network relaxation was observed after irradiation. The higher the irradiation dose was, the more obvious the peak value of tan δ was. In addition, the shearing viscosity and the storage modulus G’ became larger and the loss modulus G" became smaller than those before irradiation. Temperature sensitivity of the irradiated SBS also reduced. The SEM analysis showed that irradiation can improve the antioxygenic performance of SBS.更多还原