Improving the strength of SAN with modified glass fiber via in-situ emulsion copolymerization

To improve the interface adhesion between glass fiber (GF) and styrene acrylonit rile copolymer (SAN)，GF was treated firstly with silane coupling agent，then the surface modified with styrene (St) and acrylonitrile (AN) via in-situ emulsion polymerization. Three types of GF-g-SANs with different GF/St mass ratios were copolymerized and then filled in the melting SAN resin to prepare GF/SAN composites. The impact strength，morphology and dynamic mechanical property of the composites were characterized by impact test instrument，SEM and DMA，respectively. The Young‘s modulus of GF/SAN composite was calculated by the COX model. The results show that there is high interface adhesion between GF-g-SAN and SAN. The tough and rigid properties of the composites can be increased effectively with low content of short GF-g-SAN and high content of long GF-g-SAN，and the result predicted via the COX model is close to the experimental data.