Investigations of curing process for epoxy-isocyanate compositions
Ryszard Pilawka, Krzysztof Gorący
Quarterly No. 1, 2011 pages 44-48
DOI:
keywords: epoxy resin, epoxy-isocyanate compositions, glass transition, curing process
abstract Epoxy-isocyanate compositions have been investigated. As components, epoxy resin Epidian 6, a product of the Chemical Works “Organika Sarzyna” in Nowa Sarzyna (Poland) and isophorone diisocyanate (IPDI) have been used. The compositions were prepared by mixing the epoxy resin with the diisocyanate in a molar ratio of epoxy group:isocyanate group 1:1 and 1:2. The accelerators were: the most often used - Girard's Reagent T (GR) as well as 1-ethylimidazole (1EI) and 1-butylimidazole (1BI). The catalyst was introduced in the amount of 0.5; 1.0 and 2.0 phr of epoxy resin. The curing process of the epoxy-isocyanate system was measured using a DSC Q-100 (TA Instruments) and an ARES Rheometer (Rheometrics Scientific). The glass transition value of the fully-hardened compositions were characterized in the second run of the DSC. The introduction of an imidazole derivate decrease of the maximum effect of the crosslinking process and the gel point of epoxy-isocyanate compositions. Increasing the accelerator content leads to an increase in the glass transition temperature of the obtained composites.