在甲苯/环己烷混合溶剂体系中考察了顺酐化苯乙烯-丁二烯-苯乙烯嵌段共聚物(SBS)的制备条件,得到马来酸酐/SBS/过氧化苯甲酰质量比为30/100/1、SBS质量浓度为0.10 g/mL、过氧化苯甲酰/甲苯引发液的滴加时间为10 min及75 ℃下反应4 h的较为理想的反应条件.在此条件下既可以避免凝胶的生成,又可获得较高的接枝率(6.87%).所得顺酐化SBS经氢氧化钠溶液中和后生成钠离聚体,傅里叶变换红外光谱分析证实接枝反应和离聚体的合成均得到预期的产物.差示扫描量热分析结果表明离子化微区的存在使得离聚体在高温段有1个玻璃化转变温度.离聚体的拉伸强度、搭接剪切强度和乳化性能均随顺酐化程度的提高而改善.%In mix-solvent of cyclohexane/toluene, maleic anhydride (MAH) was grafted onto styrene-butadiene-styrene block copolymer (SBS). The results showed that MAH/SBS/benzoyl peroxide(BPO) (mass ratio) 30/100/1, concentration of SBS 10 g/mL, droping time of BPO/toluene 10 min, temperature 75 ℃, and reaction time 4 h were the optimum conditions for maleation. High grafting degree (6.87%) was obtained without gelation. Sodium ionomer was synthesized from ionization of maleated SBS, which was proved by Fourier transform infrared spectroscopy. Results from differential scanning calorimetry showed that ionic microdomains were formed in the ionomer, as it was confirmed to have a glass transition at high temperature. Maleation degree or grafting degree was an important factor for mechanical properties, bonding strength and emulsion volume. Tensile strength and lap shear strength increased with increasing of grafting degree due to great improvement of polarity. Sodium ionomer of SBS was proposed to be used as an adhesive for polar matrixes or compatibilizer for polymer blends.
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