Laser Light Scattering Studies of Epoxy Polymerization of 1,4-Butanediol Diglycidyl Ether with cis-1,2-Cyclohexanedicarboxylic Anhydride

摘要

The copolymerization of epoxy resins and anhydrides with triamine as a catalyst produces a complex three-dimensional cross-linking network, which has a variety of desirable mechanical properties, such as impact resistance. Many research efforts have been undertaken in order to understand the curing kinetics, mechanism, structure, and relationship between macroscopic properties and microstructure. Epoxy polymers formed by curing 1,4-butanediol diglycidyl ether (DGEB) with cis-1,2-cyclohexanedicarboxylic anhydride (CH) in the presence of a catalyst, benzyldimethylamine (CA), at different temperatures 60,70,80, and 90 Cl and varying amounts of catalyst were studied by investigating the laser light scattering intensities near and past the gelation threshold of the polymer products in the reaction mixture. The degree of polymerization could be determined by chemical analysis. Structural changes of the branched epoxy polymer formed during the curing process were analyzed according to the Debye-Bueche theory of light scattering for inhomogeneous solids. The change in the correlation length sigma which characterizes the inhomogeneous domain and the mean-squared average dielectric constant fluctuation Eta squared could be divided into three main stages which are responsible for the cross-linking polymerization reaction in the epoxy curing process. Reprints. (AW)