| 摘要 |
PURPOSE:To obtain the titled vinyl resin which is decreased in a change in the dispersibility in a plasticizer during paste formation with time and can give a molding excellent in transparency, resistance to blushing due to water and heat discoloration resistance, by adding a specified nonionic surfactant to the system in a process for preparing an aggregate of a vinyl resin by adding an organic liquid to a vinyl chloride resin emulsion with agitation. CONSTITUTION:Vinyl chloride or its mixture with a vinyl compound copolymerizable therewith is polymerized in an aqueous medium in the presence of a water-soluble polymerization catalyst or a redox polymerization catalyst comprising a water-soluble reducing agent and an organic hydroperoxide by using a maleic acid copolymer salt as an emulsifier. To the obtained vinyl chloride resin emulsion, a difficultly water-soluble organic liquid which can not dissolve or swell this vinyl chloride resin is added with agitation to prepare an aggregate of the vinyl chloride resin. This aggregate is dewatered and dried to obtain a particulate vinyl chloride resin. In mixing the above vinyl chloride resin with the organic liquid, a nonionic surfactant of a HLB>=10 is added to the system.
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