Novel cycloaliphatic epoxy resins. II. Curing reaction with BF3MEA and its cured properties

Publisher Website
Google Scholar
Abstract
The BF3MEA curing reaction and the cured properties of novel cycloaliphatic epoxy resins (CE‐resins), which were derived from an octadienyl compound, were studied. Gelation time and the DSC scan of the CE resins, with BF3MEA hardener, proved that the reactivity of the CE resins is intermediate among the reactivities of the conventional resins; it was found that the CE resins react faster than DGEBA, but slower than the conventional cycloaliphatic epoxy resins. The pot life of the CE‐ (III) resin with BF3MEA hardener proved to be over 30 days at a temperature of 20°C. The thermal properties are affected by the amount of BF3MEA used and the curing conditions. CE‐(III) showed the highest HDT of over 200°C with 2–3 phr of BF3MEA. The flexural properties of CE‐(I) proved to be flexible and tough. CE‐(II) exhibited the highest strength and elongation, while CE‐(III) had the same flexural properties as DGEBA. Furthermore, the blending of CE‐(II) with DGEBA produced greater flexural strength and greater elongation than each original resin had. The thermal stability at elevated temperature and the water resistance of the cured CE resins proved to be inferior to those of DGEBA and novolac epoxy resin, probably due to the use of BF3MEA. These results suggest the CE resin will provide a new application for a one‐component curing system for composites. © 1993 John Wiley & Sons, Inc.
Keywords