Preparation Of Cured Bisphenol-A Dicyanate Polymer Composites Through Covalent Integration Of Epoxidized Multi-walled Carbon Nanotubes

Multi-walled carbon nanotubes(MWCNTs) were first acid treated with concentrated HNO₃/H₂SO₄(1:1,v/v) to generate hydroxyl.Poly (acryloyl chloride)(PAC1) was esterified by hydroxyl groups on the surface of MWCNTs.The numerous acryloyl chloride groups on the outer layer were esterified with a proper amount of ethylene glycol,thus multi-hydroxyl functionalized MWCNTs were obtanined.Epoxy groups were grafted onto MWCNTs through the reaction between PAC1 and epoxy.The chemical structure of epoxy functionalized MWCNTs (E-MWCNTs) was identified by FTIR,the morphology was observed by transmission electron microscopd(TEM).E-MWCNTs were introduced into bisphenol-A dicyanate(BADCy) curing system forming a composite.The epoxy functionalized multi-walled carbon nanotubes(E-MWCNTs) participate the curing through the reaction between epoxy and cyanate groups,which was confirmed using Fourier transform infrared spectrometer(FTIR).The morphologies of both modified MWCNTs and composites were revealed by transmission(TEM) and scanning electron microscopes(SEM). Raman spectrum showed that the stress was transferred from BADCy to E-MWCNTs and thus the matrix was reinforced.When the addition was 1wt%,impact strength was 17.6 KJ/m²,which was 54.2%higher compared to neat BADCy.Flexural test measured the mechanical properties further.In addition,the glass transition temperature(Tg) of the composite were investigated using DMTA analysis.The addition of MWCNTs enhanced the thermal decomposition temperature a little bit. With the addition of MWCNTs,water absorption increased at first,and then decreased.