A novel method for grafting polymer onto the surface of nano-SiO2 particles via the esterification reaction at room temperature

atmosphere

etc.was developed and organic/inorganic composite nano-particles were prepared.The method was carried out via two steps.First

the nano-SiO2 was modified with 3-glycidoxypropyl trimethoxysilane

and then the introduced epoxy groups at the surface of the nano-SiO2 particles were converted into alkyl-hydroxyl groups.Secondly

the polymer was grafted onto the nano-SiO2 surface via the esterification reaction between the alkyl-hydroxyl groups and the carboxyl groups at the polymer terminal at room temperature.The modification of the nano-SiO2 and the resulting composite particles were characterized by XPS

FTIR

TEM and TGA.Results showed that the method has higher grafting efficiency

and the grafted polymer accounted for 55 wt%~70 wt% of the total composite particles.As a result

the particle size increased from 40 nm to 64~75 nm upon the polymer grafting.Consequently

the core-shell composite particles with polymer chains on the outside and SiO2 in the core were obtained.