Currently there are two methods of producing acrylamide glues. One is the mixing of acrylamide copolymer and polyvinyl alcohol solution the other is the copolymerization of acrylamide and polyvinyl alcohol along with initiators. Now the commonly used method is the second one. Then there is a question: is there any differences between the two methods? Will polyvinyl alcohol react with acrylamide?
Acrylamide mainly contains double bonds and functional groups of amido, and can react with a variety of reactive monomers. Polyvinyl alcohol contains only one hydroxyl functional group can carry out acetal , esterification and etherification reaction. There is little related documents regarding whether polyvinyl alcohol and acrylamide can react with each other or not.
The only reference is the graft reaction between starch and acrylamide. In the graft reaction, apply Redox systems and use acrylamide monomer to graft starch molecules. However, the molecular weight of polyvinyl alcohol is relatively large. Its graft reaction rate with acrylamide is far below the double bond radical copolymerization reaction between the acrylamide monomers. By reducing the molecular weight of polyvinyl alcohol, the reaction rate can be improved both. For example, after polyvinyl alcohol being dissolved under high temperature, adding a certain amount of hydrogen peroxide to reduce the degree of polymerization of the polyvinyl alcohol. However, reducing the degree of polymerization will weaken the glue adhesive strength and consistency, so this method is not suitable for practical use. Therefore, we can make a conclusion: the grafting reaction can be carried out between polyvinyl alcohol and acrylamide, but im comparison with the double bond radical copolymerization between acrylamide monomers, the reaction is basically negligible. We can also see from the actual production that the basic properties of copolymers and complex are the same. The only difference is that after the reaction between acrylamide and polyvinyl alcohol, miscibility of the two is better. Acrylamide monomer generate radical polymerization in a redox system. We can get the polymerization products we need by manipulating the polymerization reaction. But first we should make one thing clear: what kind of polymeric product we need?
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