Effect of Nanosilica Contents on Molecular Packing of Epoxy Resin
Volume Title: 1
1Polymer Engineering Group, Composite Research Institute, Malek Ashtar University of Technology, Tehran, Iran
2Polymer Engineering Group, Composite Research Institute, Malek-Ashtar University of Technology
Epoxy resins are one of the most prominent resins in the world. Many factors affect the mechanical properties of this family of polymers, but the effects of some factors including molecular packing on the mechanical properties are less investigated. The important factor affecting molecular packing and mechanical properties is the curing agent chemical structure. Three different curing agents including meta-phenylene diamine (m-PDA), ortho-phenylene diamine (o-PDA) and 2,4-diamino toluene (2,4-DAT) were used for curing the epoxy nanocomposites and the effect of Nano silica contents was studied on the molecular packing. the melting method was used for curing of epoxy resin. First, the curing agent was melted and then the epoxy resin was added. To study the effect of Nanosilica contents, three different Nanosilica contents including 2, 4 and 6%wt were used. The molecular packing was studied by X-ray diffraction technique. Also, the density measurements of cured epoxy resins was carried out using the Archimedes method and finally, the effect of molecular packing on the mechanical properties was investigated by tensile test. The obtained results from XRD and tensile test measurements showed that there is a direct relationship between molecular packing and mechanical propretis. By increasing the nanosilica percentage in the nanocomposite, the molecular packing and also molecular packing distribution was increased. The highest molecular packing was 4.59Å for o-PDA curing agent with 6 wt% nanosilica content. the results of Tensile tests of nanocomposites showed an increase in mechanical properties of nanocomposites up to 4% nanosilica content as function of molecular packing.