Research Equipment Grants: An Advanced Thermal Analysis System for Macromolecular Coal Studies

各种渗透剂的输运被很好地表征。煤的薄片将在高温（250-400℃）下使用高级热分析系统进行检查，以研究煤的高度交联网络结构中的运输机制，并阐明溶剂改变其化学结构的作用。​实验研究将在高于和低于Tg的高温下进行，使用厚度从20到1000 >m不等的薄片。此外，我们还将通过二甲基丙烯酸酯、三甲基丙烯酸酯和四甲基丙烯酸酯等多功能甲基丙烯酸酯反应合成高交联聚合物。这种聚合物体系具有玻璃化转变温度高和明确的交联结构。在与煤网相同的渗透剂中进行的动态和平衡研究将使它们膨胀。然后，将这两项研究的结果进行比较，以阐明交联煤网络结构的性质。将建立数学模型来描述煤中渗透剂（溶剂）的不寻常迁移。这些结果将直接适用于阐明煤加工中的传质限制，溶剂在改变化学稳定性方面的重要性以及分子解离的机制。所要求的先进热分析系统将用于分析高温下煤的大分子结构。差示扫描量热模块将提供大分子煤网络结构的玻璃化转变温度作为渗透物含量的函数。热力学和动态力学分析组件将阐明煤网在渗透剂存在下的玻璃化转变温度以下、周围和以上的粘弹性行为。热重分析模块将用于获得高温下的渗透吸收数据，并解耦扩散和松弛机制。

The transport of various penetrants in well characterized, thin sections of coal will be examined at high temperatures (250-400>C) using an Advanced Thermal Analysis System in an effort to investigate the mechanisms of transport in the highly crosslinked network structure of coal and to elucidate the effort of solvents in altering its chemical structure. Experimental Studies will be performed at high temperatures both above and below Tg using thin sections varying in thickness from 20 to 1000 >m. In addition we will synthesize highly crosslinked polymers by reaction of multifunctional methacrylates such as di', tri' and tetramethacrylates. Such polymer systems are glassy with high glass transition temperatures and well defined crosslinked structures. They will be swollen both by dynamic and equilibrium studies in the same penetrants as the coal networks. Then, the results from these two investigations will be compared in order to elucidate the nature of the crosslinked coal network structure. Mathematical models will be developed to describe the unusual transport of penetrants (solvents) in coal. These results will have direct applicability in the elucidation of the mass transfer limitations in coal processing, the importance of solvents in altering chemical stability and the mechanisms of molecular dissociation. The requested equipment, Advanced Thermal Analysis System, will be used to analyze the macromolecular coal structure at high temperature. The differential scanning calorimetry module will provide the glass transition temperature of the macromolecular coal network structure as a function of a penetrant content. The thermomechanical and dynamic mechanical analysis components will elucidate the viscoelastic behavior of coal networks below, around and above their glass transition temperature in the presence of penetrants. The thermogravimetric analysis module will be used to obtain penetrant uptake data at high temperature and to decouple the diffusional and relaxational mechanisms.