用乙烯基吡啶改性苯乙烯-丁二烯-苯乙烯嵌段共聚物

通过采用1,1-二苯基乙烯作为降活剂降低苯乙烯-丁二烯-苯乙烯嵌段共聚物(SBS)活性大分子的活性,然后用2-乙烯基吡啶进行封端聚合,合成了苯乙烯-丁二烯-苯乙烯-2-乙烯基吡啶多嵌段共聚物,研究了降活剂和单体用量及反应条件对聚合的影响。结果表明,在降活剂用量控制为活性中心的1.0倍(摩尔比)、2-乙烯基吡啶质量分数控制为活性SBS的3%以下、反应温度在60～83℃及反应时间不少于35min时能够制得相对分子质量可控且分布较窄的嵌段共聚物。

Preparation of styrene-butadiene-styrene block copolymer modified with 2-vinyl pyridine

Styrene-butadiene-styrene-2-vinyl pyridine mutiblock copolymer was synthesized by using 1,1-diphenyl ethylene as deactivator to reduce the activity of living macro-molecule of styrene-butadiene-styrene block copolymer(SBS) and 2-vinyl pyridine as polar monomer to terminate the block copolymer. The effects of deactivator and polar monomer level on the reaction were studied. The results showed that the suitable amount of deactivator was 1.0 times of the active center(mole ratio), the amount of polar monomer was 3% based on the mass of living SBS , reaction temperature was between 60 ℃ to 83 ℃ and reaction time was above 35 min. Under these conditions, the block copolymer was obtained with controllable relative molecular mass and narrow relative molecular mass distribution.