Styrenic butadiene block copolymers are an important family of commercial materials in the category of thermoplastic elastomers. These elastomers are made of separate polymeric blocks. At the beginning, there is a hard polystyrene block and in the middle, there is a polybutadiene block. Butadiene is the monomer in highest concentration in regular styrenic block copolymers. The main risk linked to the production of styrenic block copolymers on an industrial scale is the loss of control of the reactor temperature, which may lead to a temperature increase resulting in a pressure increase above its design pressure during the formation of the polybutadiene block. Fatal accidents have occurred in some chemical plants due to runaway butadiene polymerization. Critical parameters that characterize thermal runaway for the anionic polymerization of butadiene in batch reactors were established for different scale reactors: laboratory, pilot and industrial reactors. Runaway and safe conditions are identified based on the pattern of temperature and conversion trajectories near complete butadiene conversion. The resulting is useful for establishing runaway diagrams for the anionic polymerization of butadiene in batch reactors using dimensionless parameters: reaction sensitivity and cooling intensity.

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苯乙烯嵌段共聚物生产中的热失控风险分析

苯乙烯丁二烯嵌段共聚物是热塑性弹性体类别中重要的商业材料家族。这些弹性体由单独的聚合物嵌段制成。一开始是硬聚苯乙烯块，中间是聚丁二烯块。丁二烯是常规苯乙烯嵌段共聚物中浓度最高的单体。与以工业规模生产苯乙烯类嵌段共聚物相关的主要风险是反应器温度失控，这可能导致温度升高，从而导致在聚丁二烯嵌段形成期间压力升高至其设计压力以上。一些化工厂因丁二烯聚合失控而发生致命事故。对于不同规模的反应器：实验室、中试和工业反应器，确定了表征间歇反应器中丁二烯阴离子聚合热失控的关键参数。根据接近完全丁二烯转化的温度和转化轨迹模式确定失控和安全条件。结果对于使用无量纲参数（反应灵敏度和冷却强度）建立间歇式反应器中丁二烯阴离子聚合的失控图很有用。