Preparation, Characterization And Properties Of Semi-Interpenetrating Polymer Networks Based On Poly(Vinyl Chloride) Prepared Via In-Situ Chlorinating Graft Copolymerization

The purpose of this paper is to prepare the blending system of PVC/GMA, maily including poly(vinyl chloride)(PVC) with special structure and poly(glycidyl methacrylate)(PGMA), via in-situ chlorinating graft copolymerization (ISCGC). This PVC/GMA has better dispersibility, and epoxy groups can be introduced in this PVC/GMA, which provide cross-linking points. Semi-interpenetrating polymer network based on PVC/GMA can be prepared using hexamethylene diamine (HMD) which reacts with epoxy groups forming crosslinked networks, named as IPN-PVC/GMA. The reaction of HMD and the epoxy groups is feasible by variable-constant temperature FTIR, DSC and gel content test, which makes oligomers to the crosslinked network structures. And the process of the preparation of the IPN-PVC/GMA was determined. By scanning electron microscopy (SEM), the reaction uniformity between functional groups, the network phase separation and etc. were analysed, and with reference to the mechanical properties, the preliminary structural design of IPN-PVC/GMA was performed. Furthermore, preliminary researches of the IPN-PVC/GMA of some mechanical properties and thermal stability are conducted. The SEM analysis showed that because of high density of epoxy group in the system, IPN-PVC/GMA easily undergoes phase separation, the generated phase region concentration, the formation of defective dots, which results in properties of IPN-PVC/GMA can not be effectively increased, especially toughness. Therefore, with copolymerization of butyl acrylate (BA) and GMA, molecular structure was designed to improve the properties of the product.BA and GMA were added to the PVC via in-situ graft chloride reaction to copolymerize the copolymer (BA-GMA) in the system, named as PVC/BA-GMA system. The reducing of the concentration of epoxy groups improved the crosslink density of the system, when the cross-linking reaction was undergoing with epoxy groups and HMD. Semi-interpenetrating polymer network of PVC/BA-GMA system was prepared, defined as IPN-PVC/BA-GMA. Through the static mechanical properties, DSC and SEM analysis showed that BA improves the compatibility of the system. In other words, the compatibility of the IPN-PVC/BA-GMA is better than the IPN-PVC/GMA. Furthermore, the dynamic mechanical properties and thermal stability of IPN-PVC/GMA and IPN-PVC/BA-GMA were explored through the analysis of the dynamic mechanical properties analysis (DMA) and thermal stability analysis (TGA).