橡胶增韧环氧树脂机理的研究

本文研究了固化剂种类、环氧基体平均网链长度和分散相与基体间键合情况对体系韧性等的影响.结果说明,基体平均网链长度是一个更为重要的影响因素.分散相与基体间的化学键合也是重要的.文中对橡胶增韧环氧树脂的机理提出了见解.在交联密度较低的材料中,在橡胶颗粒附近叠加的应力场诱发下发生纵深度较大的断裂过程.分散相与基体间的化学键合增大该应力场强度有利于加大断裂过程区.

STUDY ON THE TOUGHENING MECHANISM OF RUBBER TOUGHENED EPOXY RESIN

The following affecting factors of rubber toughened epoxy resin system were studied: 1. kinds of curing agent used 2. the Mc value of the matrix 3. the bonding force between the dispersed phase and the matrix. Accoring to our experimental results, the average chain length between crosslinks (Mc) is found to be a much more important affecting factor, chemical bonding between the dispersed phase and the matrix is also important. A toughening mechanism of rubber toughened epoxy resin has been proposed. In the material with relatively low cross-linking density, extensive fracture process stripe is formed which is induced by the combined stress field near the rubber particles. The chemical bonding between the dispersed phase and the matrix may increase the strength of the local stress field about the rebber particles which is in favor of broading the fracture process area.