Glass fibre sizing effect on dynamic mechanical properties of cyanate ester composites I. Single frequency investigations

In order to investigate sizing effect in composite materials, we studied three types of composites, with different sizings. Dynamic mechanical analysis appeared to be a good way to characterize the α relaxation process of composites and their interphases. Results showed that α relaxation temperature shifted to higher temperatures for composites without sizing. Study of sizing extract/resin blend showed too that interphase was a mixture of polyvinyl acetate and cyanate resin. The results allow us to deduce that a plastification effect of resin by sizing could occur, with modification of crosslink density. Moreover, we can think that all resin is affected by sizing and the conversion rate in interphase is not total.