Phase Segregation in Multicomponent Polymer Mixtures

多组分聚合物混合物中的相分离

• 批准号: 9807601
• 负责人: Monica Olvera
• 金额: $ 25.5万
• 依托单位: Northwestern University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-07-15 至 2002-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9807601&HistoricalAwards=false
• 关键词: Phase; Segregation; Multicomponent; Polymer; Mixtures

9807601 Olvera This grant supports theoretical research on phase segregation in multicomponent polymer mixtures. Polymer blends are highly immiscible viscous fluids. Complex microstructures are observed during the decomposition into multiple phases. The patterns of the decomposing fluids are expected to be affected by flow. Here a systematic study will be conducted of hydrodynamic effects on the decomposition process as a function of the concentrations and degrees of polymerization of the blend components, as well as of their net repulsive interactions. Blends decomposing into two and three phases will be analyzed. Level set theory will be used to analyze interface behavior. The time-dependent microstructures under externally applied flow will also be studied. Preliminary results suggest that the break-up of the interconnected patterns found in ternary blends is strongly nonlinear. That is, the third phase rich in the minority component growing at the interfaces of the majority symmetric phases forms connecting fluid filaments that break up into mother drops with satellite droplets. This mechnaism greatly affects the growth rate of the minority phase. %%% This grant supports theoretical research on phase segregation in multicomponent polymer mixtures. Polymer blends are highly immiscible viscous fluids. Most commercially available polymers for applications are actually blends. Complex microstructures are observed during the decomposition into multiple phases. These microstructures affect the properties of the blends. The patterns of the decomposing fluids are expected to be affected by flow. Here a systematic study will be conducted of hydrodynamic effects on the decomposition process as a function of the concentrations and degrees of polymerization of the blend components, as well as of their net repulsive interactions. ***

9807601 Olvera 这项资助支持多组分聚合物混合物中相分离的理论研究。 聚合物共混物是高度不混溶的粘性流体。 在分解成多个相的过程中观察到复杂的微观结构。 分解流体的模式预计会受到流动的影响。 这里将系统地研究流体动力学对分解过程的影响，作为共混组分的浓度和聚合度及其净排斥相互作用的函数。 将分析分解为两相和三相的混合物。 水平集理论将用于分析界面行为。 还将研究外部施加流动下随时间变化的微观结构。 初步结果表明，三元共混物中互连模式的分解是强烈非线性的。 也就是说，富含少数组分的第三相在多数对称相的界面处生长，形成连接流体细丝，该流体细丝分裂成具有卫星液滴的母滴。 这种机制极大地影响了少数相的生长速度。 %%% 这项资助支持多组分聚合物混合物中相分离的理论研究。 聚合物共混物是高度不混溶的粘性流体。 大多数市售聚合物实际上都是混合物。 在分解成多个相的过程中观察到复杂的微观结构。 这些微观结构影响共混物的性能。 分解流体的模式预计会受到流动的影响。 这里将系统地研究流体动力学对分解过程的影响，作为共混组分的浓度和聚合度及其净排斥相互作用的函数。 ***