双(2,3-环氧环戊基)醚与双酚A环氧树脂混合体系固化机理的研究

用红外光谱法、电导法和化学分析对双(2,3-环氧环戊基)醚(W-95)与4,4′-二氨基二苯甲烷(MDA)的反应速度进行了测定,并和双酚A环氧树脂(E-54)与MDA的反应进行了比较。两个反应体系的表现反应活化能的测定结果接近相等。若W-95的环氧基与MDA的Ⅰ级胺和Ⅱ级胺的反应速度为k_1′和k_′,而E-54的为k_1和k_2,则它们的相对反应速度为:k_1:k_2:k_1′:k_2′=200:22:20:1。本文对W-95和E-54混合体系的固化机理也作了探讨。

A STUDY OF CURING MECHANISM OF BIS (2,3-EPOXYCYCLOPENTYL) ETHER AND BIS-PHENOL-A EPOXY RESIN MIXTURE SYSTEM

The reaction rate of bis(2, 3-epoxycyclopentyl) ether (W-95) with methylene diani-line (MDA) was determined and compared with that of bis-phenol-A diglycidyl ether (E-54) with MDA by means of infrared spectroscopy, D. C. conductivity measurement and chemical analysis. The apparent energies of activation of the two reaction systems are appoximately equal. If the reaction rates of primary amine and secondary amine with epoxy group of W-95 are k'1 and k'2, and that of E-54 are k1 and k2 respectively then the reaction rates of k1:k2: k'1: k'2 were found to be 200:22:20:1.The curing process of a system composed of a mixture of W-95 and E-54 (50/100, W/W) with MDA as curing agent was studied. It has been found that at the early stage of the reaction, the ring-opening of the E-54 epoxy groups is initiated by the primary amines with the formation of linear polymeric chains. Then, the secondary amines in the polymer molecules react further with the epoxy groups of the W-95 to form crosslinked chains.