Cure kinetics of several epoxy–amine systems at ambient and high temperatures
Epoxy-crosslinker curing reactions and the extent of the reactions are critical parameters that influence the performance of each epoxy system. The curing of an epoxy prepolymer with an amine functional group may be accompanied by side reactions such as etherification. Commercial epoxy prepolymers were cured with different commercial amines at ambient as well as at elevated temperatures. Singularly, only epoxy–amine reactions were observed with diglycidyl ether of bisphenol-A (DGEBA)-based epoxides in our research even upon post-curing at 200°C. Etherification side reaction was found to occur at a cure temperature of 200°C in epoxides possessing a tertiary amine moiety. A combined goal of our research was to understand the effect of tougheners on the cure of epoxy–amine blend. To discern the effect of tougheners on the cure, core–shell rubber (CSR) particles were incorporated into the epoxy–amine blend. It was observed that CSR particles did not restrict the system from proceeding to complete reaction of epoxy moieties. Besides, CSR particles were found to accelerate the epoxy-amine reaction at a lower level of epoxy conversion. The lower activation energy of epoxy–amine reaction of CSR incorporated system compared to control supported the catalytic effect of CSR particles on the epoxy-amine reaction of epoxy prepolymer and amine blends.
KeywordsEpoxide Hardener Crosslinker Core–shell rubber particles Near IR
The authors acknowledge the Office of Naval Research for their financial support via Award No. N00014-07-1-1057.
- 24.Ghaemy, M, Shahriari, AH, Nasab, SMA, “Study of the Cure Kinetics and Water Absorption of the DGEBA/ODA Resin.” Iran. Polym. J., 16 829–838 (2007)Google Scholar
- 32.Odian, G, Principles of Polymerization, 4th edn., pp 39–197, Chapter 2, Wiley Interscience, Wiley, New York, 2004Google Scholar
- 36.Mika, TF, Bauer, RS, “Curing Agents and Modifiers, Synthesis and Characteristics of Epoxides.” In: May, CA (ed.) Epoxy Resins: Chemistry and Technology. Marcel Dekker, Inc., New York (1988)Google Scholar
- 37.Bump, MMB, “The Effect of Chemistry and Network Structure on Morphological and Mechanical Properties of Diepoxide Precursors and Poly(hydroxyethers).” Ph.D. Dissertation, 2001, Virginia Polytechnic Institute and State University, Blacksburg, VirginiaGoogle Scholar
- 38.Fowler, EW, Pramanik, M, Rawlins, JW, “Cure Kinetics of DGEBA-Based Epoxy Prepolymer with Various Crosslinkers.” Society for the Advancement of Materials and Process and Engineering (SAMPE), Fort Worth, TX, 17–20 Oct 2011Google Scholar