Study on curing kinetics and thermal properties of biphenyl novolac epoxy resins

The curing kinetics of biphenyl novolac epoxy resins(BPNE) using 4,4'-diamino biphenyl sulfone(DDS) as curing agent was investigated by non-isothermal differential scanning calorimetry(DSC).The curing process was determined by extrapolation.The apparent activation energy was calculated using Kissinger and Ozawa methods.The reaction order of curing reaction was determined based on Crane formula.The heat resinstance of cured BPNE /DDS was studied by DSC and TGA.The results showed that the curing process was as follows:160 ℃ /2 h + 200 ℃ /2 h + 230 ℃ /2 h.The apparent activation energy,preexponential factor Arrhenius parameters(A) and reaction order of curing reaction were 61.86 kJ/mol,5.27 × 105 min-1 and 1.1 respectivly.The glass transition temperature(Tg),10% weight loss temperatures and char yield at 800 ℃ of cured system were 167 ℃,398.1 ℃and 29.37%,respectivly.The later two datas were increased by 22 ℃,11.71% than that of bisphenol A epoxy resins/DDS sysytem.