Modification And Application Of Polyvinyl Alcohol

High barrier PVA materials were prepared through adding different modifiers or grafting PU to modify the PVA, which may find wide industrial application in the field of high barrier packing materials. Mealwhile, we discussed the possibility of the non-solvent thermal process of PVA and attempted to improve the non-solvent thermal process performance of PVA by modifing. The main research contents and results of article were as follows:1,The development of PVA at home and abroad was reviewed, the application and development prospects of PVA films were briefly introduced.2,High barrier PVA coating latex was prepared by adding modifier which was synthesized by ourselves. We studied the efffect of viscosity to the coating performance of PVA conting latex, and found that modified PVA coating latex had well water-resistant preperty and can been stronghly adhered with the common polymer matix(BOPP,PE,PET ect.).The modified PVA hold the excellent barrier performance.3,PVA-g-PU was synthesized by gafting PU using TDI as gafted agent. The data of FT-IR,XPS shown that the PVA-g-PU was sucessfully prepared. DSC,TGA measurement indicated that the crystal degree and melt tempreture were not only lower through grafting PU into PVA, but also the crystal performance and melt tempreture reduced with the grafted degree increasing and the thermal degradation tempreture further improved. The mechanics measurement shown that the tensile strength of PVA-g-PU was lower,but the elongation at break and fracture energy gradually improved.4,The PVA materials having the non-solvent thermal process performance were prepared via introducing the glycerol /acetamide or glycerol/ Triethylene glycol /3,6-dioxaoctane-1/8-diol. (TEG)or PVA of different degree or modifier into the PVA matrix. TG,XRD,DSC and melt flow measurement as well as electronic universal testing machine were used to characterize that the effect of modifiers to the thermal mechanics preperties(Tg,dec,tensile strength,elongation at break,melt flow index,melt tempreture,crystal degree) and process preperties of modified PVA materials. Results indicated that adding the mixed plasticizer into PVA matix, the melt tempreture and crystal degree of modified PVA were lower and the elongation at break was higher; introduceing the modifier into PVA matix, The melt flow index of modified PVA evidently improved. the application effect of glycerol/acetamide was more than the glycerol/TEG, and when the mass ratio of PVA1799 and PVA0599 is 6:4, the mass percent of glycerol / acetamide is 30, the modified PVA had the non-solvent melt process performance and the best complex properties.