Properties Research Of Nanoparticles Modified Epoxy Resin

Epoxy, as the main matrix of advanced composites, is widely used in the national economy in several areas of the aerospace, automotive and with a good prospect of application. However, the pure epoxy after cured present comparatively low impact property and highly brittleness. So, it is meaningful to tough the epoxy for expanding the applications. In this paper, ultrafine (nanoscale) full-vulcanized powdered rubber (VP-501), multi-wall carbon nanotubes (MWNTs) and surface modified MWNTs via ATRP (atom transfer radical polymerization)(MWNTs-PGMA) were introduced into epoxy matrix respectively and Jeffamine (T403), isophorone diamine (IPDA), methylhexahydrophthalic anhydride (MeHHPA) hardeners were utilized to prepare different epoxy samples. Analysis of mechanical tests, curing kinetics, DMA, SEM observation of the tensile fractures and nanoparticle dispersion in the matrix were applied to compare the different epoxy composites systems.It is observed that adding VP-501into epoxy would have toughness that the impact property improved in all cure systems. Observed by SEM, the introduce of VP-501into all the three epoxy systems would ameliorate the interface of the samples and the VP-501nanoparticles would disperse in thematrix homogenously no more than10wt%or affecting the toughness of thesamples. Comparatively, in the VP-501/MeHHPA/E-51system, the impactproperties of the samples were improved obviously and Tg of the samplestested via DMA were obviously increased by about10℃. The performanceof VP-501/T403/E-51system was improved slightly and it is need to adddiluent669(ethylene glycol diglycidyl ether) to reduce the viscosity of thesystem VP-501/IPDA/E-51in the process or difficult to remove bubbles andeasy to make VP-501aggregated, impacting the tests results.The addness of MWNTsinto epoxy matrix result in the improvement ofimpact performance with the three different hardeners. In theMWNTs/T403/E-51system, the Tg observed by DMA was increased by15℃and the effective damping area decreased slightly. In theMWNTs/IPDA/E-51system, the Tg and the effective damping area showedlittle change. In the MWNTs/MeHHPA/E-51system, the Tg and theeffective damping area were also increased. The SEM images of tensilefracture of all the three systems showed from smooth to rough. It issuggested that the content of MWNTsin the matrix is no more than0.5wt%or it would affect the mechanical performance of composite due to thepresence of the aggregates of MWNTs.MWNTs-PGMA, prepared via ATRP, ameliorated the dispersion ofMWNTsin the matrix. The samples demonstrated excellent performance by adding MWNTs-PGMA into E-51/MeHHPA system resulting fromimproving of tensile property, flexure property and impactproperty,especiallythat the impact property of the samples at the content of0.5wt%MWNTs-PGMAincreased by105%to the pure resin, and the Tgincreased by about15℃. The tensile fracture is even rough whereMWNTs-PGMAwould not easily pull out from the epoxy resin, but embedand penetrate due to that MWNTs-PGMAhas a good compatibility with theepoxy resin.