Suspension Polymerization of Hydrophilic Monomers

PI提出通过悬浮聚合研究亲水（水可膨胀）微粒的生产。这种聚合物颗粒有许多实际用途，包括：(1)在小分子量或大分子量溶质的色谱分离中；(2)作为离子交换树脂；(3)作为填料床反应器的填料；(4)作为海洋防污涂料的脱模剂；(5)作为固定化酶的载体；（六）药品中药物的释放剂；(7)在反应工程中用作催化剂。微粒的结构和几何特性在所有情况下都会影响它们的可用性。在悬浮聚合中，反应发生在悬浮在无机相中的有机单体相中；通常 水。产物固体聚合物析出，含有少量（10%）未反应的单体。所需要的产物有：粒径分布、形状、孔径分布、分子量分布和交联间分子量控制。在这项研究中，PI计划对亲水单体的间歇悬浮聚合进行动力学建模。具体而言，工作将包括以下活动：i.开发适用于亲水性单体与交联剂的共聚/交联反应的动力学模型，包括凝胶点前后和玻璃化之前；2。测定产物在胶凝点前的分子量分布与反应动力学常数和单体投料比的关系；3。间歇反应器中悬浮聚合反应工程模型的建立Iv.确定影响这类悬浮聚合中粒径分布的关键参数；v.以2-甲基丙烯酸羟乙酯（HEMA）和乙二醇二甲基丙烯酸二酯（EGDMA）作为交联剂进行悬浮聚合实验，并在线或离线测定颗粒和分子量分布；6 . EGDMA/HEMA间歇悬浮聚合体系方程预测与实验结果的比较。

The PI proposes to study hydrophilic (water swellable) microparticle production by suspension polymerization. Such polymer particles have many practical uses including: (1) in chromatographic separations of small or large molecular weight solutes; (2) as ion-exchange resins; (3) as filling materials in packed bed reactors; (4) as releasing agents for antifouling paints in marine science; (5) as carriers for enzyme immobilization; (6) as releasing agents for drugs in pharamaceuticals; and (7) as catalysts in reaction engineering. Structural and geometric characteristics of the microparticles affect their usability in all cases. In suspension polymerization, reaction takes place in an organic monomer phase which is suspended in an inorganic phase; usually water. The product solid polymer precipitates out and contains small amounts (10%) of unreacted monomer. The desired products have controlled: particle size distribution, shape, pore size distribution, molecular weight distribution and molecular weight between crosslinks. In this research the PI plans to do kinetic modelling of batch suspension polymerizations of hydrophilic monomers. Specifically, the work will include the following activities: i. development of the kinetic models applicable to the copolymerization/crosslinking reaction of a hydrophilic monomer with a crosslinking agent, both before and after the gelation point and until vitrification; ii. determination of the molecular weight distribution of the product before the gelation point as a function of the kinetic constants of the reactions and the feed ratio of the monomers; iii. development of the models for reaction engineering in suspension polymerization in batch reactors; iv. determination of the critical parameters that affect the particle size distribution in this type of suspension polymerizations; v. conduct experiments of suspension polymerizations with 2- hydroxyethyl methacrylate (HEMA) and ethylene glycol dimethacrylate (EGDMA) as a crosslinking agent and determination on- or off-line of the particle and molecular weight distributions; and vi. comparison of the predictions of the system equations with experimental results for EGDMA/HEMA batch suspension polymerizations.