Synthesis and curing properties of fluorinated curing agent for epoxy resin based on natural soybean isoflavones

A novel fluorinated diamine curing agent (AFPCO) was synthesized from natural isoflavone daidzein, used to cure hydrogenated epoxy resin (DGEHBPA) and tested against commercially available DGEHBPA cured with 4,4 '-diaminodiphenylmethane (DDM). The results show that the non-isothermal curing reaction kinetics study found AFPCO to be less reactive than DDM. Compared to DDM, the AFPCO cured material increases the energy storage modulus, impact strength and flexural strength by 34%, 51% and 12% respectively. The AFPCO cured material performs worse in terms of decomposition temperature, but the residual carbon rate exceeds that of DDM/DGEHBPA by 230% and the flame retardancy reaches VL-94 V-1 level. In contrast to the hydrophilic nature of the material after DDM curing, the introduction of fluorine in AFPCO gives the material a water contact angle of 92.19 degrees, which meets the criteria for hydrophobic materials. In contrast to low dielectric constant resins prepared with conventional fluorinated curing agents, AFPCO/DGEHBPA has a high dielectric constant, but still exhibits a low numerical value of 0.0338 in dielectric loss.