Modified ultra-high molecular weight polyvinyl alcohol as well as preparation method and application thereof

The invention belongs to the field of modified PVA (polyvinyl alcohol), and particularly relates to modified ultrahigh molecular weight polyvinyl alcohol as well as a preparation method and application thereof. The preparation method of the modified ultrahigh molecular weight polyvinyl alcohol comprises the following steps: adding polyvinyl alcohol powder into a reaction kettle, continuously adding a certain amount of solvent as a reaction carrier, heating, stirring, adding a modifier, and washing and drying a product by using a washing solvent after the reaction is finished, thereby obtainingthe modified ultra-high molecular weight polyvinyl alcohol. The invention aims to obtain a polyvinyl alcohol product with ultrahigh polymerization degree through chemical modification, the molecularweight is increased through cross-linking action, and double bonds are added on a polymer chain, so that the activity can be improved, and the application of the polyvinyl alcohol product as a reactive auxiliary agent is facil