在iCVD期间对蒸汽相动态的分析:自由基启动由tert-甲氧化物
1Robert Frederick Smith School of Chemical & Biomolecular Engineering, Cornell University, 120 Olin Hall, New York, Ithaca 14853, United States.
概括
这项研究模拟了在启动化学蒸汽沉积 (iCVD) 中的二甲基-丁过氧化物 (TBPO) 分解,揭示了它完全分解为乙和乙. 这一发现纠正了iCVD模型中的单体压力过高估计.
科学领域:
- 聚合物科学 聚合物科学
- 化学工程是化学工程的重要组成部分.
- 材料科学 材料科学 材料科学
背景情况:
- 启动化学蒸气沉积 (iCVD) 是广泛使用的,但反应性蒸气阶段,特别是启动器分解,是不太了解的.
- 现有的iCVD模型往往误解了发起者行为,导致了解沉积动力学的不准确性.
- 三甲氧化物 (TBPO) 是一个常见的发起者,但对于ICVD条件,还没有特定的分解模型.
研究的目的:
- 开发和验证TBPO在ICVD反应堆中的分解模型.
- 准确量化TBPO转化并实时了解其分解产品.
- 研究TBPO分解对单体压力和沉积动力学的影响.
主要方法:
- 将Pirani压力表集成到ICVD设置中,用于实时蒸汽相组合分析.
- 校准Pirani测量仪读数与批量实验中已知的组合相比.
- 在连续ICVD操作下对TBPO分数转换的量化和使用阿雷尼乌斯参数的动力分析.
主要成果:
- 在ICVD条件下,TBPO通过第一阶段Arrhenius动力学完全分解为乙和乙.
- 极端的部分压力低于检测极限,气体分子固态度在分解过程中发生变化,影响单体压力测量.
- 在TBPO分解过程中,循环基甲酸盐 (CHMA) 单体在蒸汽阶段显示微不足道的反应.
- 开发的蒸汽相模型与经典的线性聚合理论保持一致,并预测在高线温度下观察到的激活能量变化.
结论:
- 该研究提供了iCVD中TBPO分解的第一个动力模型,澄清了蒸汽相化学.
- 精确的TBPO分解建模解决了单体压力计算中的差异,这对于iCVD过程的理解至关重要.
- 这些发现为控制和优化iCVD过程提供了更强大的框架,特别是用于聚合物合成.
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