Shell particles in micrometer level have been prepared by a jet milling

and it was used as filler to modify the properties of epoxy resin (EP) by melting-blending. The organic phase of the shell particles was much helpful to improve the interfacial intension. When appropriate content of shell particles were added to EP matrix

the free vol- ume size and its intensity of the composites decreased

but the intensity of the second lifetime I2 increased. It was at- tributed to the formation of the interfacial layers between the shell particles and EP matrix. This good interfacial property was necessary for efficient stress transfer between the particles and EP matrix. Therefore

the mechanical properties of the composites were approved remarkably.