Viscoelastic and thermally stable PDMS-SiO2 filled epoxy adhesive joint on steel substrate

The epoxy based composite adhesives have been prepared by reinforcing polydimethylsiloxane (PDMS) treated SiO2 nanoparticle with varying content of 2, 4, and 6 wt% in comparison of neat epoxy. PDMS treated SiO2/epoxy composites are fabricated using an ultrasonic mixing process. Dynamic mechanical analysis has been carried out to evaluate the viscoelastic properties on every group of the epoxy composite. The effect of PDMS treated SiO2 nanoparticles reinforcement on viscoelastic properties of epoxy resin have been studied in the terms of storage modulus and tan values with respect to temperature. The dispersion conditions of the PDMS-SiO2 nanoparticles in epoxy adhesive have been identified by field emission scanning electron microscopy (FESEM). Thermal gravimetric analysis has been used to identify the thermal stability of each group of PDMS-SiO2/epoxy composite. The effect of PDMS-SiO2/epoxy composite adhesive on the lap joints of mechanically treated mild steel substrate has also been investigated. POLYM. COMPOS., 39:2889-2896, 2018. (c) 2017 Society of Plastics Engineers