Study Of PVA Blow Molding Film

Along with the development of modern plastic packing profession,method of productionand study on PVA film is mainly using extrusion and blow molding process. At present, thestudy of PVA blow molding film is film is blow out after adding plasticizer to PVA, thenanalyzed the influence of plasticizer on performance of PVA film. In this paper,under thepremise of maintaining certain mechanics performance of PVA film,PVA film is studied afteradding different ratios' TDI and glycerin, and the influence of different ratios' TDI andglycerin on mechanical properties is investigated. At the same time plasticized mechanism ofglycerin and cross-linked mechanism of TDI in different systems is studied.As to glycerin, there are different plasticized mechanisms in different systems, yetglycerin always plasticize the system which contain glycerin. When the content of otheringredients in system are unvaried, with glycerin increasing, tensile strength and tearingstrength of PVA blow molding film reduce, but broken extending rate increases. For example(take the crosswise data as example): when PVA is 1kg, and TDI is 1ml, the content ofglycerin increase from 300g to 450g, the tensile strength PVA blow molding film deduce from53.29MPa to 41.27MPa ,the tearing strength of PVA blow molding film deduce from184.48MPa to 152.8MPa, and broken extending rate of PVA increase from 291.35% to421.05%. As to TDI, there are different cross-linked mechanisms in different systems, yet it ingeneral has cross-linked performance. And when the contents of others ingredients in systemare unvaried, with the content of TDI increasing, tensile strength and tearing strength of PVAblow molding film increase first, Afterwards it reduces;and broken extending rate of blowmolding film reduces first ,afterwards it increases. For example: when PVA content is 1kg,and glycerin content is 1ml, EVOH content is 40g,with the content of TDI increase from0.5ml to 2.5ml, the tensile strength PVA blow molding film increase from 35.45MPa to41.14MPa then reduce to 39.71MPa, the tearing strength of PVA blow molding film increasefrom 147.47MPa to 158.14MPa then deduce to 143.78MPa, and broken extending rate of PVAdeduce from 462.18% to371.68 % then increase to 424.27%.The relationship between TDI and glycerin is studied in PVA film.