Grafting of poly(glycidyl methacrylate) onto nano-SiO2 and its reactivity in polymers

Abstract

In order to introduce reactive groups onto the surface of inorganic nanoparticles, which can take part in the in-situ reaction when being compounded with matrix polymers to produce nanocomposites, poly(glycidyl methacrylate) (PGMA) was grafted onto silane pretreated nano-SiO2 by free-radical polymerization. This paper mainly studied the factors that influence the graft polymerization, including monomer concentration, initiator consumption, reaction temperature and reaction time. The reactive kinetics of the PGMA grafted on the nanoparticles with 4,4′-diaminodiphenylsulfone (DDS) in polypropylene (PP) or polystyrene (PS) matrices were evaluated by differential scanning calorimetry (DSC). It was shown that the appearance of PP or PS in the model composites did not change the overall curing reaction mechanism and the grafted nanoparticles gave a stable dispersion in the good solvent for the grafting chains.