Studies Of The Technology Of Synthesizing Polyvinyl Alcohol 0588

Polyvinyl alcohol (PVA) is a typical water-soluble and crystalline polymer. Because of its excellent mechanical properties and surface activity, it has been used in many industries. Specially, it has the water-soluble and excellent property of membrane- formed, other polymers have it very difficult. The property of polyvinyl alcohol is close correlation by the degree of polymerization and alcoholysis, the application domain is decided by its property. Because of the vice of the general polyvinyl alcohol variety in heat-resisting, water-resisting and wriggle-resisting, its application scope has limited. In order to further enhances and improves the polyvinyl alcohol's property, it is extremely essential to expanded the application scope of polyvinyl alcohol and research the difference technology of the polyvinyl alcohol (different degree of polymerization and alcoholysis). PVA0588 (the degree of polymerization is 500, the degree of alcoholysis is 88%) is a kind of difference polyvinyl alcohol product with the low degree of polymerization and the partial alcoholysis. Because of its excellent surface activity, it may be used as the emulsification of VAc emulsion polymerization to make PVAc and VAE, and as the dispersant of chloroethylene suspend polymerization. Because of its small molecular weight, therefore its property of membrane- formed is overmatch the other PVA variety in the water absorbability, the water-solubility and the flexible. It is widespread application in Chinese traditional medicine with new dosage-form. For example: may be used as the membrane material of daub preparation, the membrane material of the membrane preparation, the carrier of gelatin preparation and so on.Polyvinyl acetate resin was prepared by solution polymerization of vinyl acetate with azobisisobutyronitrile as initiator and methylic alcohol as solvent, then polyvinyl alcohol was obtained by the solution alcoholysis recation with lower alkaline method. The research indicated that, by solution polymerization of yvinyl acetate and solution alcoholysis recation with lower alkaline method , the lower degree of polymerization and alcoholysis of polyvinyl alcohol resin( PVA0588) was obtained. The influence mainly factor of polymerization includes the dosage of initiator azobisisobutyronitrile, the dosage of the solvent methylic alcohol, the reaction temperature, the reaction time and so on. With increasing the the dosage of initiator azobisisobutyronitrile and solvent methylic...