Collaborative Research: GOALI: Design of Chemically Self-Regulated, Acrylic Coatings Processes through Iterative Use of Chemical Quantum Calculations and Spectroscopic Methods

合作研究：GOALI：通过迭代使用化学量子计算和光谱方法设计化学自调节丙烯酸涂料工艺

• 批准号: 0932786
• 负责人: Andrew Rappe
• 金额: $ 23.42万
• 依托单位: University of Pennsylvania
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-01 至 2012-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0932786&HistoricalAwards=false
• 关键词: Collaborative; Research; GOALI; Design; Chemically

0932786RappeIntellectual Merit The PIs' previous study of free-radical solution homo- and co-polymerization of a class of alkyl acrylates, such as ethyl and n-butyl acrylates, revealed very substantial, spontaneous thermal polymerization at 120-180oC in the absence of added thermal initiators. Monomers such as styrene and many methacrylates, not alkyl acrylates, had been known to undergo spontaneous polymerization. In their work, they carried out laboratory experiments and identified several factors influencing the initiation step in the spontaneous polymerization. They have also made advances in efficiently using chemical quantum-level computations on supercomputers to study the kinetics of polymerization reactions.Building on these successes, they plan to employ an iterative research strategy that includes first-principles density functional theory (DFT) calculations, design of experiments, batch laboratory experiments, and spectroscopic analyses. It is aimed at quantitatively understanding the kinetics, the reaction mechanisms, and the relevant intermediates and transition states for initiation and chain transfer in spontaneous thermal polymerization of methyl, ethyl, and n-butyl acrylates using this integrated research strategy, with the ultimate goal of designing "chemically self-regulated" polymerization processes for the production of high-performance acrylic resins. It will involve a broad spectrum of activities such as: (i) proposing initiation model mechanisms, (ii) estimating molecular geometries of reactants, transitions states, intermediates, and products using DFT calculations on supercomputers, (iii) validating and calculating reliable thermo chemistry using Gaussian-n theory, (iv) designing laboratory batch polymerization experiments to capture the initiating and product species and to verify the controlling nature of the species and mechanisms, (v) conducting polymerization experiments, (vi) conducting spectroscopic analyses, (vii) comparing end group structures from the chemical quantum calculations and spectroscopic analyses, (viii) calculating reaction rate coefficients from the quantum chemical data, (ix) comparing the theoretical predictions with values obtained from the experiments, and (x) validating the control living species.Broader Impacts The potential impacts of this project are societal (through improved safety), environmental, economic, and in human resource development. Spontaneous thermal polymerization allows for the production of higher quality, environmentally-friendlier solvent-borne paints and coatings at lower operating costs. Low molecular weight, polymer and oligomer solutions even at high weight percent solids have adequately low viscosity, thus requiring less organic solvents to be sprayable and brushable. The use of less or no added thermal initiators (normally the most expensive component of a resin formula) and significantly shorter reaction times lower the operating costs. The presence of less residual groups from azonitrile and organic peroxides thermal initiators (which adversely affect polymer properties such as resistance to UV radiation) in the final product and the use of the quantitative understanding in optimal control of molecular properties improve the resin quality. The PI and Co-PIs will train and mentor two doctoral research assistants as well as six undergraduate (REU) students, who will participate in broad range of research activities from quantum-level computations and supercomputing to laboratory experiments and spectroscopic methods, some of which will be conducted at DuPont Marshall Laboratory. The project results will be released to the public at conferences and in journal and conference proceedings papers. Students from under-represented groups will be selected, trained and mentored in this project.

0932786 RappeIntellectual Merit PI之前对一类丙烯酸烷基酯（如丙烯酸乙酯和丙烯酸正丁酯）的自由基溶液均聚和共聚的研究表明，在不添加热引发剂的情况下，在120- 180 ℃下发生了非常显著的自发热聚合。单体，如苯乙烯和许多甲基丙烯酸酯，而不是烷基丙烯酸酯，已经知道进行自发聚合。在他们的工作中，他们进行了实验室实验，并确定了影响自发聚合中引发步骤的几个因素。他们还在高效利用超级计算机上的化学量子计算研究聚合反应动力学方面取得了进展，并计划在此基础上采用迭代研究策略，包括第一性原理密度泛函理论（DFT）计算、实验设计、批量实验室实验和光谱分析。它的目的是定量地了解的动力学，反应机理，以及相关的中间体和过渡状态的引发和链转移的甲基，乙基和正丁基丙烯酸酯的自发热聚合使用这种综合研究策略，与设计的最终目标“化学自我调节”的聚合工艺生产高性能的丙烯酸树脂。它将涉及广泛的活动，例如：（i）提出引发模型机制，（ii）在超级计算机上使用DFT计算估计反应物、过渡态、中间体和产物的分子几何形状，（iii）使用Gaussian-n理论验证和计算可靠的热化学，（iv）设计实验室分批聚合实验以捕获引发和产物物质并验证物质和机理的控制性质，（v）进行聚合实验，（vi）进行光谱分析，（vii）比较来自化学量子计算和光谱分析的端基结构，（viii）从量子化学数据计算反应速率系数，（ix）比较理论预测与从实验获得的值，及（x）验证控制活物种。更广泛的影响本项目的潜在影响是社会（通过提高安全性）、环境、经济和人力资源开发。自发热聚合允许以较低的运营成本生产更高质量、更环保的溶剂型油漆和涂料。低分子量的聚合物和低聚物溶液即使在高重量百分比固体下也具有足够低的粘度，因此需要较少的有机溶剂来进行喷涂和刷涂。使用较少或不添加热引发剂（通常是树脂配方中最昂贵的组分）和显著缩短的反应时间降低了操作成本。在最终产品中存在较少的来自偶氮腈和有机过氧化物热引发剂（其不利地影响聚合物性能，例如耐紫外线辐射性）的残留基团，以及在分子性能的最佳控制中使用定量理解，提高了树脂质量。PI和Co-PI将培训和指导两名博士研究助理以及六名本科生（REU），他们将参与从量子级计算和超级计算到实验室实验和光谱方法的广泛研究活动，其中一些将在杜邦马歇尔实验室进行。项目成果将在会议上、期刊和会议论文中向公众公布。将在该项目中挑选、培训和指导来自代表性不足群体的学生。