Fundamental Studies of Polymerization Processes

在美国，每年大约有600亿磅的合成聚合物在各种各样的聚合反应器中生产。这些反应器生产的产品的最终用途包括从合成服装到乳胶漆。聚合物可在间歇、半间歇和连续反应器中制造。聚合反应工程试图通过工艺设计和控制方面的创新来改善聚合物的生产。三个重要的方面包括：(1)需要了解反应器的动力学，其中大的热释放，高粘度和难以去除的热量导致设计有效控制机制的困难；(2)开发聚烯烃（聚乙烯、聚丙烯等-商品聚合物）生产的连续液相和气相工艺；(3)开发缩聚聚合物的新工艺（例如纤维和工程塑料就是用这种方法生产的）。PI计划继续对间歇、半间歇和连续聚合反应器进行实验和理论研究，以了解发生的化学和物理现象，并利用这种理解：(1)改进反应器设计，以更好地控制聚合物性能，并最大限度地减少困难的动力学。通过定量地确定产生振荡和稳定性问题的操作条件和系统参数的范围，设计过程可以既满足聚合物产品的规格要求，又具有良好的经济性，同时又避免了那些参数组合导致的复杂的动态行为。(2)为反应器和聚合物颗粒开发新型在线传感器，使产品质量控制更加紧密，并将这些新型在线聚合物性能传感器与反馈策略相结合，提供控制方案，从而实现安全动态运行和产品质量的紧密控制。(3)为现有的和新兴的聚合物产品设计新的反应器。

Approximately 60 billion lbs/year of synthetic polymers are produced in the U.S., in a wide variety of polymerization reactors. The ultimate use of the products from these reactors ranges from synthetic clothing to latex paints. Polymers are manufactured in batch, semibatch, and continuous reactors. Polymerization reaction engineering attempts to improve the production of polymers through innovations in process design and control. Three areas of importance include (1) a need to understand the dynamics of the reactors in which large heat release, high viscosity, and difficult heat removal contribute to difficulties in designing effective control mechanisms; (2) the development of continuous liquid and gas phase processes for polyolefin (polyethylene, polypropylene, etc., - commodity polymers) production; and (3) developing new processes for polymers made by polycondensation (fibers and engineering plastics, for example are produced by this method). The PI plans to continue experimental and theoretical research on batch, semibatch, and continuous polymerization reactors in order to develop an understanding of the chemical and physical phenomena occurring, and use this understanding to: (1) Devise improved reactor designs which provide better control control of polymer properties and also minimize difficult dynamics. By quantitatively determining the ranges of operating conditions and system parameters for which oscillations and stability problems arise, design procedures can be developed which satisfy the polymer product specifications and have good economics but which avoid those parameter combinations that lead to difficult dynamic behavior. (2) Develop new types of on-line sensors for the reactor and polymer particles which allow closer quality control of the product and the combination of these new on-line polymer property sensors with feedback strategies to provide control schemes which lead to safe dynamic operation and close control of product quality. (3) Devise new reactor designs for existing and emerging classes of polymer products.