Free radical polymerization (FRP) of acrylates is under conventional lab-scale batch conditions characterized by strong nonisothermicity. Hence, side reactions with a high activation energy such as β-scission are highly relevant already at intermediate temperatures (313–333 K), broadening the log-molar mass distribution and decreasing the average molar masses. To avoid thermal runaway, one can design jacket temperature profiles or exploit semibatch reactor operations. Model-based design with stochastic solvers is a strong tool to support the identification of optimal reactor settings although rarely applied upon mutually addressing reactor temperature changes and concentration variations due to (multicomponent) feeding strategies. Here such coupled design is performed for lab-scale solution FRP of n-butyl acrylate, benefiting from i) many inputted kinetic parameters (e.g., Arrhenius parameters) that have been benchmarked based on individual experimental techniques, ii) previous kinetic Monte Carlo validation under batch nonisothermal conditions including a prediction of reactor temperature extrema; and iii) systematic screening of semibatch operations in combination with flat and stepwise (average) jacket temperature profiles. It is demonstrated that many molecular properties are safely within hand for different total batch times, taking 2,2′-azobis(2-methylpropionitrile) as initiator. The model for viscosity control is also employed, expanding the traditional output of FRP simulations.

中文翻译：

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利用（多组分）半批次和夹套温度程序安全调节丙烯酸正丁酯溶液自由基聚合的分子特性

丙烯酸酯的自由基聚合 (FRP) 在以强非等温性为特征的常规实验室规模间歇条件下进行。因此，具有高活化能的副反应（如β断裂）在中间温度（313-333 K）下已经高度相关，扩大了对数摩尔质量分布并降低了平均摩尔质量。为了避免热失控，可以设计夹套温度曲线或开发半间歇式反应器操作。使用随机求解器的基于模型的设计是支持识别最佳反应器设置的强大工具，尽管很少应用于相互解决由于（多组分）进料策略引起的反应器温度变化和浓度变化。这里对实验室规模的解决方案 FRP 进行了这种耦合设计丙烯酸正丁酯，受益于 i) 许多输入的动力学参数（例如，阿伦尼乌斯参数），这些参数已基于个别实验技术进行基准测试，ii) 先前在批次非等温条件下的动力学蒙特卡罗验证，包括反应器温度极值的预测；iii) 结合平坦和逐步（平均）夹套温度曲线对半间歇操作进行系统筛选。结果表明，以 2,2'-偶氮双（2-甲基丙腈）为引发剂，对于不同的总批次时间，许多分子特性都可以安全掌握。还采用了粘度控制模型，扩展了 FRP 模拟的传统输出。