| ABS resin is a kind of engineering plastics with excellent combined properties. Because of its impact resistance shock-resistant, high rigidity, able to bear chemistry corroding, mechanical properties and electric performance, easy shaping process and colored, size stability and good surface gloss, it has been widely used in industries such as the machinery, cars, electron, household appliances, instrument and apparatus and building etc. PVC/ABS soft epidermis material can achieve the excellent impact toughness and meet the requirement of vacuum shaping craft at the same time. The vacuum shaping craft requires the epidermis material having very high hot intensity and tensile stretch and better demoulding deflection property and size stability. This kind of ABS graft material is the same with general ABS resin in polymerization arts and crafts mainly including synthesization of PB latex and the preparation of the graft materials.ABS resin is a rubber-toughened thermoplastic, including the dispersed rubbery phase is polybutadiene (PB) and the continuous rigid phase is acrylonitrile-styrene copolymer (SAN). As a kind of elastomer, polybutadiene should be grafted with SAN copolymer in order to improve the adhesion between ABS copolymer and PVC resin for excellent properties.In this study we synthesized the ABS graft materials and blended with PVC resin and plasticizer for car instrument board epidermis materials which can improve the. In order to know special function of the car instrument board epidermis material more deeply in essence, a series of PVC/ABS blends and PVC/SAN blends are studied. In this thesis we synthesized a series of ABS and SAN copolymer by adopting the AN content and he proportions of copolymer monomers i.e. styrene/α-methyl styrene, and blended the copolymers with PVC resin and different proportions plasticizer. We characterized the influence on dynamical mechanics properties and phases dispersion of the blends using dynamic mechanical analysis (DMA) and scanning electron microscope (SEM) and transmission electron microscope (TEM) with different AN contents and styrene/α-methyl styrene and the addition of plasticizer.In the third chapter we studied the influence of AN content on dynamical mechanics properties. As a result when AN content is 25% the blend becomes partial miscible showing two Tg peaks shift close together with obscure boundary. ABS graft copolymer particles are dispersed in PVC matrix relative uniformly by observation from SEM micrograph. The blends with the other AN contents have immiscible with two separated peaks. With the increase of AN content the reciprocity is deduced and the phase separation happens gradually. The PVC/SAN blends are immiscible, however, with any AN content, which is in accord with the SEM result.In the fourth chapter we addedα-MSt in the copolymerization monomer partially or completely substituting the St and study the influence on the miscibility of PVC/ABS and PVC/SAN blends. When the St is substituted byα-MSt partially the miscibility is improved. There is only one Tg peak with the AN contents are 20% and 25% which shows better miscibility. When the AN content is 35% the Tg peaks of the two phase move to each other. In the PVC/SAN blends the miscibility is also improved by the addition ofα-MSt. The SEM characteristic shows the same result. At the same time we also studied the influence on the miscibility of the blends which St is substituted withα-MSt completely. The result of DMA shows the miscibility is improved further than before. The blends become miscible with the AN are 25% and 35% which shows only one Tg peak. So all above results show the addition ofα-MSt into the comonomers improves the miscibility obviously, which broaden the miscibility window. In the research we found that at the same condition the two phases of the blends disperses well. So we fixed the AN content with 25% while adjusted the proportion of styrene/α-methyl styrene to study the which is the best ratio of theα-MSt in the comonomers. The blends start to be miscible whenα-MSt/St is 30/70 with the AN content is 25%. The improved miscibility of PVC/α-MSAN blends obviously depends on theα-MSt.In the fifth chapter we studied the influence of addition of plasticizer on the miscibility. The phase separation of the blends is aggravated because of the addition of plasticizer. DMA results show that with the increase of the plasticizer addition the Tg peaks of the two phases separated further. With the increase of AN content more plasticizer disperses into the PVC phase. So the interaction between DOP and SAN phase becomes weaker which cause the shift range decreases. Consequently theΔTgs become larger. From the SEM results the size of the phase domain becomes bigger, which also dedicate the poor miscibility.In the sixth chapter we studied on the heat deflection property of PVC/ABS and PVC/α-MABS soft materials. The result dedicates that with the increase of AN content, the storage modulus increases and the heat deflection property of the soft material is enhanced. The heat deflection property of the blends depends on the AN content obviously. When the AN content is 35% the sample has no deformation, which means having perfect heat deflection property. From the SEM micrograph we find the PVC/ABS blends and PVC/ABS/DOP blends are immiscible with any AN content. After adding the plasticizer the Tgs of the two phases of the blends change obviously with the change of the AN contents. When the AN content is over 35% more plasticizer DOP distribute into the PVC phase and the Tg move to the low temperature in large range, however, the Tgs of the SAN copolymers change a little which cause the soft materials exhibit perfect heat deflection property.
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