聚甲基丙烯酸甲酯/環氧樹脂摻合系統之相行為研究

Abstract

本論文研究在不同硬化溫度條件下，Epoxy/PMMA摻合系統，以芳香族DDS為硬化劑，求得硬化動力、相分離機制、相形態和機械性質。實驗結果發現在這個系統內無酯交換反應發生。利用SEM研究當PMMA含量大於臨界點時，摻合系統的相分離過程和其形態。利用tanδ損耗高度比值可用來描述系統的相形態。不同硬化條件下，Epoxy/PMMA摻合系統可得分散相、共連續相、相反轉的最終相形態。Epoxy/PMMA系統，硬化遵守自催化反應動力模式，且在PMMA/Epoxy摻合物系統中，硬化反應速率低於純Epoxy系統。只有當共聯連續相或相反轉存在時，機械性質才會有明顯的下降。這是由於PMMA相和Epoxy相並無強烈的鏈結。

Phase separation mechanism, morphologies, cure kinetics, and the mechanical properties of epoxy/PMMA blend cure with DDS have been investigated. Transesterification does not occur in this blend system during curing. When the PMMA content in the blend is greater than a critical value, phase separation occurs during and the related morphologies were characterized by SEM. The tanδ loss peaks from DMA analyses were used to characterize phase separation of blend. Depending on cure temperature and PMMA content in the blend, the finally cured product may result in different morphologies such as single phase, PMMA particles, co-continuous, or epoxy particles. Cure kinetics study indicates that the cure reaction of the epoxy/PMMA blend follows the autocatalytic mechanism. The cure rate of the epoxy/ PMMA blend, in general, is lower than the neat epoxy. Prior to the phase inversion, mechanical properties observed are comparable the neat epoxy resin because of poor interfacial adhesion.