Computational thermodynamics of multicomponent compressible polymer solutions

多组分可压缩聚合物溶液的计算热力学

• 批准号: 371253-2008
• 负责人: Rey, Alejandro
• 金额: $ 2.88万
• 依托单位: McGill University
• 依托单位国家: 加拿大
• 项目类别: Collaborative Research and Development Grants
• 财政年份: 2008
• 资助国家: 加拿大
• 起止时间: 2008-01-01 至 2009-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=411558
• 关键词: Computational; thermodynamics; multicomponent; compressible; polymer

Production of polyolefins using solution polymerization methods takes place at high pressure and results in a multicomponent polymer solution reactor effluent. Comodity polymers , such as polyethylene, are produced using solution polymerization methods under high pressure and temperature. During the downstream heat processing stage , changes in operating conditions lead to phase separation and the emergence of different phases containing different polymer compositions as well as a complex morphology. The complex multiphase morphology in turn affects the heat transfer process in the heater unit, leading to changes in heater efficiency and pressure drops through the course of the heater. This phase separation may occur to such a degree that phase inversion occurs. The phase separation of this multiphase-multicomponent flowing stream is dictated by instabilities, such as spinodal decomposition, that seek to reduce the energy of the system. The polymer is fractionated between the liquid phases, yielding different polymer molecular weight distribution curves and attendant physical properties. To optimize the design and control of these heating units a better fundamental knowledge of the thermodynamic principles that govern phase separation in compressible multicomponent polymer solutions are required. This proposal presents a research program that integrates polymer molecular thermodynamics, mathematical process modeling, and high performance computing to accurately predict the thermodynamics and interfacial properties of polyethylene ternary solutions, and the kinetics of phase separation of compressible polymer solutions under condition relevant to polyolefin manufacturing based on solution polymerization methods.

使用溶液聚合方法生产聚烯烃是在高压下进行的，并导致多组分聚合物溶液反应器流出。共聚聚合物，如聚乙烯，是在高压和高温下使用溶液聚合方法生产的。在下游热加工阶段，操作条件的变化导致相分离，出现包含不同聚合物组成的不同相以及复杂的形态。复杂的多相形态反过来影响加热器单元内的传热过程，导致加热器效率的变化和加热器整个过程中的压降。这种相分离可能发生到这样的程度，以至于发生相位反转。这种多相多组分流动的相分离是由寻求降低系统能量的不稳定性决定的，例如调幅节点分解。聚合物在液体之间进行分馏，得到不同的聚合物分子量分布曲线和相应的物理性质。为了优化这些加热装置的设计和控制，需要更好地了解控制可压缩多组分聚合物溶液中相分离的热力学原理。提出了一种集成了聚合物分子热力学、数学过程建模和高性能计算的研究方案，以准确地预测聚乙烯三元溶液的热力学和界面性质，以及基于溶液聚合方法的聚烯烃生产相关条件下可压缩聚合物溶液的相分离动力学。