Modeling and computation of solvent penetration in glassy polymers

玻璃态聚合物中溶剂渗透的建模和计算

• 批准号: 148911900
• 负责人: Professor Dr.-Ing. Paul Steinmann
• 金额: --
• 依托单位: Abteilung Maschinenbau
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2009
• 资助国家: 德国
• 起止时间: 2008-12-31 至 2012-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/148911900?language=en
• 关键词: Modeling; computation; solvent; penetration; glassy

The main goal of this proposal is the computational modeling of solvent penetration in glassy polymers. For most engineering applications, Fick s law accurately describes diffusive processes, but one of the applications where it miserably fails is in glassy polymers near the glass transition temperature. In the vicinity of the glass transition temperature, when a low molecular weight solvent diffuses into a glassy polymer, the latter is caused to undergo a rubber-glass phase transition. The diffsive process follows non-Fickian behavior. Whereas the classical Fickian diffusion is referred to as case I diffusion, diffusion in glassy polymers is known as non-Fickian „case II diffusion“. A typical system undergoing case II diffusion is polymethylmethacrylate (PMMA) and methanol, for example.Modeling polymers which undergo case II diffusion is of particular interest in pharmaceutical and automotive industries, for example. Due to the importance of diffusion in many industrial and biological processes, a complete examination from a variety of perspectives and techniques is necessary. One tool at hand is the computational modeling at which this project aims. Hereby, an all-embracing theoretical model is to be set up extending existing approaches. Thus the very challenging modeling of non-Fickian behavior is one main task of this project. The numerical implementation of this ambitious theory is to be done subsequently in order to computationally model distinct typical applications from engineering or biomechanics.

该建议的主要目标是溶剂在玻璃态聚合物中渗透的计算建模。对于大多数工程应用，菲克定律准确地描述了扩散过程，但在玻璃化转变温度附近的玻璃态聚合物中，菲克定律却不幸地失败了。在玻璃化转变温度附近，当低分子量溶剂扩散到玻璃状聚合物中时，使后者经历橡胶-玻璃相转变。扩散过程遵循非Fickian行为。而经典的菲克扩散被称为情况I扩散，玻璃状聚合物中的扩散被称为非菲克“情况II扩散”。例如，经历第二类扩散的典型系统是聚甲基丙烯酸甲酯（PMMA）和甲醇。由于扩散在许多工业和生物过程中的重要性，从各种角度和技术进行全面检查是必要的。手头的一个工具是这个项目所针对的计算建模。在此基础上，扩展现有的研究方法，建立一个综合性的理论模型。因此，非常具有挑战性的非Fickian行为的建模是这个项目的主要任务之一。这一雄心勃勃的理论的数值实现是随后完成，以计算模型不同的典型应用工程或生物力学。