Epoxy resins with mesogenic groups were prepared from diglycidyl ether of 4,4'-biphenol (DGEBP) as rigid block and 4,4'-diaminodiphenylsulphone (DDS). Curing kinetics were investigated using size exclusion chromatography in the 155-175 degrees C range above the melting temperature. It was found that the ratio r - k(2)/k(1) of secondary to primary amino hydrogen rate constants displays unusual values higher than unity and decreased on increasing the temperature. This effect was assumed to be due to the nematic structure in which polymerization takes place before reaching the gel point. References: 13
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