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Article to prepolymer dispersion method, combined with acetone, toluene diisocyanate ester (TDI), polyether (PPG) and dimethylolpropionic acid (DMPA) self-emulsifying anionic aqueous polyurethane (PU), is synthesized in this polyurethane / polyacrylate PUA composite emulsion for seed preparation, and then in an autoclave were used PU and PUA vinyl chloride as a seed for the in situ graft copolymer emulsion prepared PU / PVC (PU / PVC) and polyurethane / polyacrylate / PVC composite emulsion (PUA / PVC) resin. Currently, this study has yet to see a publicly reported. By dynamic laser particle size analyzer and transmission electron microscopy (TEM) investigated the microscopic morphology of PU / PVC PUA / PVC composite particles in the particle size and its distribution, as well as latex, the results show that the typical nuclear: PU / PVC composite latex / shell particle structure, PUA / PVC composite latex with island-type multi-core-shell structure. PU / PVC and PUA / PVC composite latex particle size increases, the growth of the VC monomer molecules in the PU and PUA seed, polymerization. With 1,2-dichloroethane as a solvent, and both of the composite resin separation study found that the increase of the content of the rubber phase, the composite resin of the grafting efficiency increases, and the graft rate declined. Focus relative to the amount of the PU molecular weight and PU or PUA rubber on the mechanical properties of the resin. The adding of the appropriate amount of the rubber elastic body to improve the notched impact strength of the material, when the PU or PUA content of 12wt%, the impact strength reached a maximum of four to eight times of the emulsion of PVC. PU molecular weight also affects the mechanical properties of the composites increased nearly 10 times the impact strength of the composite material, PU molecular weight of 7000 to 10000, while the tensile strength was less affected. Through investigation, 1,4 - butanediol as a the PU chain extender best to improve the mechanical properties of the composite effect. In addition, the study found the PU appropriate crosslinking help PU / PVC and PUA / PVC composite performance improvement. By dynamic mechanical analysis instrument (DMA), TA - 2000 Thermal Analyzer, XWB 300F type Vicat softening point temperature measuring instrument, and transmission electron microscopy (TEM) and scanning electron microscopy (SEM) by means of the composite resin and the material The dynamic mechanical properties, thermal stability, Vicat softening point temperature, morphology and material fracture surface tested characterization. DMA studies show that with the the PU, or PUA rubber phase content increases the mechanical loss peak of the material is low-temperature region to high temperature gradually move a certain improvement in compatibility; TEM photos show: a highly uniform dispersion of the rubber phase in the PVC, the two-phase interface; SEM: material gap section of a typical ductile fracture. PU and PUA rubber phase added, so that the thermal stability of the composite resin slightly lower.
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