Novel silicone–phenyl contained amine curing agent for epoxy resin. 2. Isothermal cure and dynamic mechanical property

• A novel silicone–phenyl contained aliphatic polyamine was first time employed as the curing agent of epoxy resin.
• The isothermal curing kinetics of DGEBA/PSPA was investigated with DSC.
• The isoconversional method was used to analyze the effective activation of the curing reaction.
• Dynamic mechanical analysis showed the cured resin has a glass transition temperature of more than 110 °C.

A multifunctional silicone–phenyl contained aliphatic polyamine, PSPA, was originally synthesized and employed to cure bisphenol A epoxy resin (DGEBA) isothermally, and the curing reactions of DGEBA/PSPA were systematically investigated by DSC measurement at 55, 60, 65 and 70 °C. The model fitting kinetic analysis confirmed that the reaction rate could be simulated with an autocatalytic Kamal model from start to initiation of diffusion control stage. Taking the diffusion effects into account, the extended Kamal model was applied to fit the experimental reaction rate, and acquired good agreement results. The multi-frequency dynamic mechanical analysis shows that the cured DGEBA/PSPA appears at a β relaxation in low temperature and at an α relaxation in higher temperature interval (>80 °C). The relaxation activation energies for the α and β relaxations are 80.51 and 832 kJ/mol, separately.