Initiated chemical vapor deposition (iCVD) of poly(alkyl acrylates): A kinetic model
Initiated chemical vapor deposition (iCVD) of poly(alkyl acrylates): A kinetic model
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DOI：
10.1021/ma0601621
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发表时间：
2006-05-16
期刊：
影响因子：
5.5
通讯作者：
Gleason, KK
中科院分区：
文献类型：
--
作者：
Lau, KKS;Gleason, KK
在两部分的研究中，描述了丙烯酸烷基酯聚合物的引发化学气相沉积（iCVD）的实验研究和动力学模型分析。在第二部分中，建立了一个动力学模型来研究iCVD聚合的反应机理。该模型将引发，传播和终止以及初级自由基终止和重组的表面聚合事件。通过使用一个多响应参数估计程序的基础上最大限度地减少一个决定性的标准，该模型拟合紧密的丙烯酸丁酯iCVD测量的单体表面浓度的变化对聚合反应速率和聚合物分子量的影响的实验数据。模型传播和终止速率系数，15 540和0.98 × 10（6）L/ mol。s，与液相丙烯酸丁酯自由基聚合的相应值15 460和10（6）L/ mol吻合较好。s，分别。该模型捕捉到了典型的液相自由基聚合的速率和分子量的单体浓度的线性依赖关系。在低浓度下，该模型进一步捕获了非线性速率行为，这归因于显着的初级自由基终止。敏感性分析显示，模型性能良好，模型参数的趋势符合实际。这些结果为表面驱动的iCVD聚合提供了强有力的支持，该聚合令人惊讶地类似于本体相自由基聚合。经过验证的iCVD动力学模型将最终促进工艺放大，并提供新iCVD化学品可行性的先验预测。
In a two-part investigation, an experimental study and a kinetic model analysis of the initiated chemical vapor deposition (iCVD) of alkyl acrylate polymers are described. In this second part, a kinetic model was developed to examine the reaction mechanisms of iCVD polymerization. The model incorporated surface polymerization events of initiation, propagation, and termination as well as primary radical termination and recombination. By using a multiresponse parameter estimation procedure based on minimizing a determinant criterion, the model fitted closely to experimental data on butyl acrylate iCVD that measured the effect of a change in monomer surface concentration on both the rate of polymerization and polymer molecular weight. Model propagation and termination rate coefficients, 15 540 and 0.98 x 10(6) L/ mol . s, respectively, matched well with those of liquid-phase butyl acrylate radical polymerization, 15 460 and 10(6) L/ mol . s, respectively. The model captured the linear dependencies of rate and molecular weight to monomer concentration typical of liquid-phase radical polymerization. At low concentrations, the model further captured the nonlinear rate behavior, which was attributed to significant primary radical termination. Sensitivity analysis revealed a well-behaved model with model parameters that trended realistically. These results provided strong support for a surface-driven iCVD polymerization that is surprisingly analogous to bulk-phase free radical polymerization. A proven iCVD kinetic model would ultimately facilitate process scale-up and provide a priori predictions on the feasibility of new iCVD chemistries.