Developing an Optimum Cure Cycle Using Differential Scanning Calorimetry for tetra Functional Epoxy Cured with a Cycloaliphatic Amine

The cure process of a tetra functional epoxy resin, tetraglycidyl-4,4'-diaminodiphenylmethane (TGDDM) with a cycloaliphatic amine, 2,2’-dimethyl-4,4’-diamino dicyclohexyl methane, has been analyzed using isothermal and dynamic differential scanning calorimetry (DSC). Using dynamic DSC scan at 2.5oC/min, four isothermal cure temperature 80 , 90, 100, and 110oC were selected from the beginning of the cure reaction and peak temperature because main kinetic events of the reaction occur in that area. The isothermal run at 80oC was obtained at one-fourth distance from the initial and the peak temperature which gives information on the kinetic order of the studied system. The results obtained by the isothermal cure were confirmed by the combination of dynamic and isothermal cure. The results showed that there were residual reaction heats after isothermal cure at all selected isothermal temperatures. The result showed that the curing of TGDDM/Cycloaliphatic amine system cured by a three step curing cycle give a higher Tg and lower heat of reaction during the dynamic segment of the cure cycle.

Keywords:

epoxy , kinetic , cure cycle , DSC