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Polyvinyl chloride (PVC) is one of the five major thermoplastic General plastic, has a wide range of applications in various fields, due to its outstanding durability and performance advantages, as well as the unique technical and economic characteristics, and broad development prospects. But its thermal stability is poor, low toughness at room temperature when, easily break upon impact. Manufacturing high-performance PVC material, especially PVC, high toughness alloy, toughening components need to be added, i.e. the impact modifier; polyvinyl chloride belong to the polar polymer, melt viscosity, low thermal stability, easy high temperature plasticizing, for the high strength of the non-plasticized polyvinyl chloride materials processing, the need to use the plastics processing aids, such that the processing performance is improved. This study the requirements of high-performance PVC materials, the use of acrylate monomer were synthesized having a core-shell structure of the polyacrylate (ACR) the plasticization processing aid of the impact modifier, and polyacrylate , graft copolymerization of acrylic esters with chitosan (CTS), impact resistance and antibacterial function copolymer modified additives. Acrylate, butyl (BA), methyl methacrylate (MMA) for the hard and soft monomers, potassium persulfate (KPS) as initiator, was synthesized by the method of seed emulsion polymerization of the monocoque structure of the soft core of the impact modifier I-ACR Chitosan (CTS) as a natural antimicrobial agent, containing a variety of functional groups, highly reactive, can be subjected to oxidation, reduction, graft reaction. By comparison choice of a variety of chitosan performance good performance water-soluble chitosan, chitosan produce free radicals triggered ceric ammonium nitrate (CAN), graft copolymerization with MMA reaction. Having antibacterial properties of chitosan and acrylate monomer graft copolymerization, having antibacterial properties was synthesized impact modifier CTS-ACR; emulsion solids, respectively, the gel fraction and the monomer conversion rate, ACR on PVC mechanical properties as indicators investigated two systems emulsifier, initiator selection and dosage, hard and soft monomer feed ratio, polymerization temperature and reaction time on the the ACR performance of impact, to determine the optimal synthesis conditions, try the easy powder of the drying method. Characterization of polymer structure using infrared spectroscopy (IR), differential scanning calorimetry (DSC) to examine its multiple glass transition temperature, laser particle size analyzer test emulsion particle size and distribution to explore the core-shell structure of the ACR. The intrinsic viscosity of the main indicators synthesized by emulsion polymerization, the processing aid having a higher molecular weight P-ACR. P-ACR preparation and performance testing: BA, the MMA monomer, potassium persulfate as initiator, synthesized by the emulsion polymerization method P-ACR resin as the main indicators of the intrinsic viscosity of the resin to the P-ACR investigated the emulsion The relationship between the various factors and the molecular weight of the polymer in the polymerization system, to adapt the present system the following conclusions: (1) an emulsifying agent, an appropriate increase can improve the molecular weight of the P-ACR, but too much emulsifying agent is not conducive to the improvement of the molecular weight; ( 2) lead to the increase of the concentration will reduce the molecular weight of the P-ACR; (3) The lower the polymerization temperature conducive to the increase in molecular weight of P-ACR; (4) in the improved polymerization process conditions, to extend the reaction time may improve the P- ACR molecular weight; (5) With the increase of the BA feeding amount, P-ACR molecular weight becomes large. Three polyacrylate polymer and polyvinyl chloride were used to blend, to obtain blends. To test mixing time and mixing temperature on the mechanical properties of PVC / ACR blends. Test different copies ACR impact modifier modified PVC material, impact properties, tensile properties, heat resistance. Dispersed by scanning electron microscopy blends slice position to observe the the blended material impact fracture brittle or ductile fracture. Two ACR impact modifier can significantly improve the impact resistance of PVC, with the ACR increase in the number of copies, the greater the toughness of PVC, I-ACR mechanical properties slightly better than the CTS-ACR. Test PVC / CTS-ACR material antimicrobial, found a blend material having excellent antibacterial properties. Testing rheological properties of blends containing different number of copies of the P-ACR found that P-ACR can significantly improve the processing properties of PVC, the more the number of copies of the P-ACR, the better the performance of materials processing.
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