Polyvinyl chloride (PVC) is one of the five thermoplastic universal plastics, has a wide range of applications in various fields, because of its outstanding durability and comprehensive performance advantages, as well as unique technical and economic characteristics, broad prospects for development. But it has poor thermal stability, low toughness at room temperature and is easy to fracture when impacted. Manufacturing high-performance PVC materials, especially high toughness PVC alloy, need to add toughening ingredients, that is, impact resistance modifier; Polyvinyl chloride belongs to polar polymer, melt viscosity, low thermal stability, not easy to high temperature plasticizing, for high strength non-plasticizing polyvinyl chloride material processing, the need to use plasticizing processing additives, so that the processing performance is improved.
This study aimed at the requirement of high performance of PVC material, the use of acrylic monomers, respectively with core-shell structure was synthesized polyacrylic ester (ACR), impact modifiers and polyacrylate plasticizing processing AIDS, by acrylic ester with chitosan (CTS) graft copolymerization, obtain copolymerization modified additives with shock and antibacterial functions. In this study, butyl acrylate (BA), methyl methacrylate (MMA) as soft and hard monomers, potassium persulfate (KPS) as initiator, through the method of seed emulsion polymerization synthesis of soft core and hard shell anti-impact modifier I-ACR, chitosan (CTS) as a natural antibacterial agent, contains a variety of functional groups, highly reactive, can be oxidized, reduced, Grafting and other reactions. By comparing the properties of various chitosan, water-soluble chitosan with good properties was selected. Cerium ammonium nitrate (CAN) was used to initiate chitosan to produce free radicals, and graft copolymerization reaction with MMA occurred.
Cov tshuaj tiv thaiv -impact modifier CTS-ACR yog tsim los ntawm graft copolymerization ntawm chitosan thiab acrylate monomers nrog antibacterial thaj chaw. Noj cov ntsiab lus ntawm emulsion, gel tus nqi, monomer hloov pauv tus nqi thiab txhua yam khoom ntawm ACR ntawm PVC raws li indexes, cov kev cuam tshuam ntawm emulsifier, pib thiab ntau npaum, pub piv ntawm cov tawv thiab mos monomer, polymerization kub thiab cov tshuaj tiv thaiv lub sij hawm ntawm ACR zog ntawm ob. tshuab tau tshawb xyuas los txiav txim siab qhov zoo tshaj plaws synthesis tej yam kev mob thiab sim kom qhuav txoj kev uas yooj yim rau powdery. Cov qauv ntawm ACR yog tus cwj pwm los ntawm infrared spectroscopy (IR), ntau lub iav hloov pauv kub tau tshawb xyuas los ntawm qhov sib txawv thermal scanning calorimetry (DSC), thiab particle loj thiab kev faib tawm ntawm emulsion tau ntsuas los ntawm laser particle loj analyzer. Cov kev pab cuam P-ACR nrog siab molecular hnyav tau tsim los ntawm emulsion polymerization nrog cov yam ntxwv viscosity raws li qhov ntsuas tseem ceeb.
The preparation and properties of P - ACR test: with BA, MMA as the monomer, potassium persulfate as initiator, synthesis of P - ACR resin by using the method of emulsion polymerization, with P - characteristic viscosity of ACR resin as the main index, the various factors in the emulsion polymerization system and the relationship between polymer molecular weight, get used to this system the following conclusions: (1) appropriate emulsifier The molecular weight of P-ACR can be increased by adding more emulsifiers, but too much emulsifier is not conducive to the increase of molecular weight. (2) The increase of initiator concentration will decrease the molecular weight of P-ACR; (3) Low polymerization temperature is beneficial to increase the molecular weight of P-ACR; (4) Prolonging the reaction time can increase the molecular weight of P-ACR under the improved polymerization process; (5) With the increase of BA feed quantity, p-ACR molecular quantity increases. Three kinds of polyacrylate polymers were blended with polyvinyl chloride to obtain the blend material. The effects of mixing time and temperature on mechanical properties of PVC/ACR blends were tested.
Qhov cuam tshuam tsis kam, tensile zog thiab kub tsis kam ntawm PVC hloov nrog sib txawv ACR cuam tshuam hloov pauv tau raug sim. Lub dispersion ntawm qhov sib tov tau pom los ntawm kev tshuaj ntsuam xyuas electron microscope, thiab qhov nkig los yog zawm tawg ntawm qhov cuam tshuam ntawm qhov sib xyaw tau pom. Ob qhov kev hloov pauv ntawm ACR tuaj yeem pom tseeb txhim kho qhov cuam tshuam ntawm PVC. Nrog rau qhov nce ntawm tus lej ntawm ACR, qhov tawv ntawm PVC nce, thiab cov khoom siv tshuab ntawm I-ACR yog me ntsis zoo dua li ntawm CTS-ACR. Cov khoom siv tshuaj tua kab mob ntawm PVC / CTS- cov ntaub ntawv ACR tau sim, thiab pom tias cov khoom sib xyaw muaj cov khoom siv tshuaj tua kab mob zoo heev. Nws tau pom tias P-ACR tuaj yeem txhim kho cov cuab yeej ua haujlwm ntawm PVC. Qhov ntau P-ACR, qhov zoo ntawm cov khoom ntawm PVC.
