Study on the amidation of methyl methacrylate on the nano-TiO_2 surface

The surface grafting process was used to graft coupling agent KH-550 on nm TiO2,then introduce methyl methacrylate monomer through the amidation reaction and finally form a coating by free radical polymerization.The morphology and chem.compn.-structure of the org.coating on the particles were characterized by the tests such as TEM and FTIR,and the influence of the reaction conditions on the structure and performance of the composed particles was researched with the methods of DSC and TGA.Coupling agent in 2 different concns.was used to pre-treat the nm TiO2 in order to raise the grafting ratio.It was found that the grafting ratio of the composed particles was increased with coupling agent concn.,the grafting amt.and monomer amidation ratio increased were increased with prolonging the NaOH dropping time and raising the monomer concn.,and the grafting ratio of the coated particles and the monomer transition were increased with increasing the initiator concn.and monomer concn.