| PVA water-soluble film is a completely degradable plastic film.PVC and PE and other plastic film,the PVA water-soluble film was the advantages of easy degradation and radid dissolution,and was paid great attention.As a new environmet-friendly material,PVA water-soluble film show a better application prospects.In this paper,the solubility and mechanical properties of PVA water-soluble films were optimized.The single-factor experiment was used to study the technological conditions of the films,such as the concentration of the reaction solution,the reaction time and the reaction temperature,and the effect of drying temperature on the solubility and mechanical properties of PVA water-soluble films.On the basis of experiments,the pilot process of PVA water-soluble thin film with the production capacity of 1kt/a was designed and the main equipment was calculated and selected.Single factor experiment was used to determine the ratio of raw materials for PVA water-soluble film synthesis,the reaction conditions and the a suitable film drying conditions.The results showed that when the mass concentration of PVA is 15%,the mass concentration of starch is 3.34%,the concentration of initiator 445 is 1.67%,the concentration of glycerol is 1.67%,the amount of sodium dodecyl sulfate Of the mass concentration of 1.25%,the reaction time is 45 min and the reaction temperature of 90℃.The performance indexes of the PVA water soluble films are shown in follows: the solubility of PVA was 36.1s,the tensile strength was 30.30 MPa and the elongation at break was 194.5%.The film prepared under these conditions has better solubility but lower tensile strength.By optimizing the preparation conditions,adding the concentration of 1% of the enhancer sodium carboxymethyl cellulose can increase the tensile strength of the film to 45 MPa.The prepared PVA water-soluble films were characterized by differential thermal analysis(DSC),infrared spectroscopy(FTIR)and scanning electron microscopy(SEM).The results showed that the synthesis process has the participation of esterification reaction,and the initiator 445 can make the film morphology become very smooth,but its thermal performance is reduced. |
