silica sol hybrid was synthesized by the hydrolysis reaction of ethyl silicate(TEOS) at 25℃ under alkaline conditions.Then a series of modified epoxy resins were successfully prepared by using the silica sol hybrid. IR spectrum

epoxy value indicated that the silica sol hybrid is incorporated into epoxy resin. The modified epoxy resin was cured with isophorone diamine (IPDA)

Then investigated the cured materials via measuring the flame retardancy

glass transition temperature (

T

g

)

thermal stability

tensile strength and elongation

microstructure of the cured materials

The effects of chemical modification

physical mixing and the content of the TOES on the properties of the composites were discussed. The results show that the modified epoxy resin obtained by chemical reaction has better performance. The limiting oxygen index and thermal stability of the cured product are obviously higher than that of pure epoxy resin

and the tensile strength and other mechanical properties have been greatly improved

which achieved that the flame retardant

heat resistance and mechanical properties of the epoxy materials were increased at the same time.