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Abstract：
An epoxy compound\'s polymer structure can be characterized by the glass transition temperature (Tg) which is often seen as the primary morphological characteristic. Determining the Tg after manufacturing thermoset-molded parts is an important objective in material characterization. To characterize quantitatively the dependence of Tg on the degree of cure, the DiBenedetto equation is usually used. Monitoring polymer network formation during molding processes is therefore one of the most challenging tasks in polymer processing and can be achieved using dielectric analysis (DEA). In this study, the morphological properties of an epoxy resin-based molding compounds (EMC) were optimized for the molding process using response surface analysis. Processing parameters such as curing temperature, curing time, and injection rate were investigated according to a DoE strategy and analyzed as the main factors affecting Tg as well as the degree of cure. A new method to measure the Tg at a certain degree of cure was developed based on warpage analysis. The degree of cure was determined inline via dielectric analysis (DEA) and offline using differential scanning calorimetry (DSC). The results were used as the response in the DoE models. The use of the DiBenedetto equation to refine the response characteristics for a wide range of process parameters has significantly improved the quality of response surface models based on the DoE approach.
摘要：
环氧化合物的聚合物结构可以通过玻璃化转变温度(Tg)来表征,其通常被视为主要形态特征。在制造热固性模制部件之后确定Tg是材料表征中的重要目标。为了定量表征Tg对固化程度的依赖性，通常使用DiBenedetto方程。因此，在成型过程中监测聚合物网络的形成是聚合物加工中最具挑战性的任务之一，可以使用介电分析（DEA）来实现。在这项研究中,使用响应面分析优化了基于环氧树脂的模塑料（EMC）的形态性能，以用于成型过程。固化温度等加工参数，固化时间,根据DoE策略和注射速率进行了研究，并分析了影响Tg和固化程度的主要因素。基于翘曲分析，开发了一种在一定固化程度下测量Tg的新方法。固化程度通过介电分析(DEA)在线测定,并使用差示扫描量热法(DSC)离线测定。结果用作DoE模型中的响应。使用DiBenedetto方程对各种工艺参数的响应特性进行细化，显著提高了基于DoE方法的响应面模型的质量。
