EFFECT OF SiO2 PARTICLES ON PHASE-SEPARATION OF POLY(METHYL METHACRYLATE)/POLY(STYRENE-co-ACRYLONITRILE) BLENDS
SiO2粒子对PMMA/SAN共混体系相分离行为的影响

The effect of fumed silica(SiO_2) particles on the phase behavior of poly (methyl methacrylate)(PMMA)/poly(styrene-co-acrylonitrile)(SAN) blends was studied by using small angle laser light scattering(SALLS) and dynamic rheology.The phase diagram of PMMA/SAN blends unfilled and filled with SiO_2 particles was obtained.The results revealed that the influence of SiO_2 particles on the phase separation behavior of the blend matrix was related to the components of PMMA/SAN blends.Comparing with the 60/40(W/W) PMMA/SAN blends,the addition of a small amount of SiO_2 particles could increase the phase-separation temperature(T_s) and could hardly result in the changes of phase separation mechanism,namely,both filled and unfilled blends obeyed the spinodal decomposition mechanism.However,for 30/70 PMMA/SAN blends,the addition of SiO_2 particles decreases T_s.This phenomenon was attributed to the component difference between the surface of SiO_2 particles and the matrix of PMMA/SAN blends.