Measurement and Modeling of Polymerization Kinetics for Process and Product Development

生产率的提高、用现有设备制造新的聚合物材料以及用具有成本效益和环境友好的版本取代工艺的能力是聚合物行业的关键驱动因素。另一方面，学术研究主要集中在利用生物可再生原料合成新的聚合物，或开发具有可控微结构的高价值应用功能材料。工业界和学术界的共同兴趣是需要聚合动力学和机理的基本知识来指导聚合物合成条件和工艺开发工作。我的研究填补了这一相当大的知识空白，方法是应用专门的脉冲激光技术来测量通过标准实验无法获得的关键动力学速率系数，在为表示聚合体系而制定的详细机械模型中捕获这些知识，并在相关条件下进行有针对性的实验研究，以测试和验证模型。我的研究计划的长期目标是提高对自由基聚合体系的理解，使第一原理建模成为工艺设计和优化的可靠和可靠的工具，减少设计新聚合材料所需的实验。我的团队最近的研究表明，水和其他氢键溶剂(特别是那些带有羟基的溶剂)对自由基聚合动力学有很大影响。因此，计划在未来五年进行的研究将测量溶剂选择对共聚物微观结构的影响，以实现在水和有机溶液中生产同等材料所需的工艺修改。一个特别关注的焦点是疏水和功能性亲水单体的共聚动力学，因为所产生的材料可用于水性和水溶涂料以及用作颜料分散剂的特种产品和一系列消费品。这项研究还将进一步深入了解氢键对聚合动力学的作用，我们将继续系统地研究这一问题，以增加机理模型的预测能力，减少对实验的要求。此外，该项目还培训研究生掌握对加拿大聚合物工业非常重要的专业知识，并让本科生接触到实用的材料开发和反应工程问题。

Increased production rates, the manufacture of new polymeric materials with existing equipment, and the ability to replace processes with cost-effective and environmentally-friendly versions are key drivers in the polymers industry. Academic research, on the other hand, is primarily focused on the synthesis of new polymers from bio-renewable feedstock, or the development of functional materials with controlled microstructures for high value applications. Common to both industrial and academic interests is the need for fundamental knowledge of polymerization kinetics and mechanisms to guide polymer synthesis conditions and process development efforts. My research fills this considerable knowledge gap by applying specialized pulsed-laser techniques to measure key kinetic rate coefficients not accessible through standard experimentation, capturing that knowledge in detailed mechanistic models formulated to represent polymerizing systems, and undertaking targeted experimental studies at relevant conditions to test and validate the models. The long term objective of my research program is to improve understanding of radical polymerization systems to the point where first-principles modeling is a reliable and robust tool for process design and optimization, reducing the experimentation required to design new polymeric materials. My group's recent efforts have demonstrated that water and other hydrogen bonding solvents (particularly those with a hydroxyl group) greatly influence radical polymerization kinetics. Thus, the planned research over the next five years will measure the impact of solvent choice on copolymer microstructure to enable the process modifications required to produce an equivalent material in aqueous and organic solution. A particular focus is the copolymerization kinetics of hydrophobic and functional hydrophilic monomers, as the resulting materials have uses in water-borne and water-soluble coatings and specialty products used as pigment dispersants and in a range of consumer products. The research will also provide further insight into the role of hydrogen bonding on polymerization kinetics, a subject we continue to systematically investigate to increase the predictive power of mechanistic models and reduce the requirement for experimentation. In addition, the program trains graduate students in expertise important to the Canadian polymer industries, and exposes undergraduate students to practical material development and reaction engineering issues.