Patent ID: 9701799
Date: 2017-07-11
CPC Classifications: B05D,C08J,C08K,C08L

Claim:
1. A method for preparing a transparent gas barrier composite film, comprising: providing a polyvinyl alcohol containing aqueous solution; providing a graphene oxide dispersed aqueous solution; performing a blending procedure, to blend the polyvinyl alcohol containing aqueous solution with the graphene oxide dispersed aqueous solution to obtain a casting solution wherein a weight ratio of graphene oxide in the graphene oxide dispersed aqueous solution to polyvinyl alcohol in the polyvinyl alcohol containing aqueous solution is less than 0.1 wt %; performing a cross-linking procedure for 1-6 hours, to add a cross-linking agent into the casting solution to have in-situ cross-linking reaction; performing a film-casting procedure, to coat the casting solution after the in-situ cross-linking reaction on a substrate to form a coating and dry the coating so as to obtain a composite film which has a crosslinking content being about 1.0 wt. %; and performing an isothermal crystallization procedure for 1-6hours at a specific temperature to have crystals of polyvinyl alcohol grow and to have graphene oxide induce the crystals of polyvinyl alcohol to grow so as to incorporate with graphene oxide and the cross-linking agent to form a hybrid network structure of the crystals of polyvinyl alcohol, graphene oxide and the cross-linking agent.