The Synthesis And The Application Study Of Soy Protein Adhesives

The methods of modifying SPI (Soy Protein Isolate) are including physics, chemistry, enzyme and biotechnology. In this paper, the graft copolymerization of SPI with vinyl monomers was studied, in order to improve the bonding properties of the adhesives.In this paper, the graft copolymerization of SPI with vinyl acetic ester (VAc) was initiatively studied. The ammonium persulphate (APS) - sodium bisulfite (NaHSO3) was used as a redox initiator, and 3mol/L urea solutions was used as a denaturing agent. The FTIR spectra of SPI and grafted copolymers indicated that the VAc had been grafted on the SPI. The hot-pressing conditions (hot-pressing temperature, hot-pressing pressure, hot-pressing time) have a big effect on adhesive's bonding properties, so the best conditions of hot press was discussed through the orthometric experiment. At the basement of a theory the adhesive's bonding properties is determined by the interaction balance of polar-apolar group between adhesives and the wood surface, so the relationships between bonding properties and reaction conditions of affecting grafting reaction (the same as grafting percent) was studied. The optimum conditions were obtained. The synthetical adhesive solutions were made by formula design. The optimum formula proportion was determined. At last, the physicochemical properties of different adhesive's systems were studied.At the base of former study, the graft copolymerization of SPI with glycidyl methacrylate (GMA) was also studied. The relationships between bonding properties and reaction conditions of affecting grafting reaction were studied. In order to make certain how the major conditions and the interactions of major conditions affect the bonding properties, a three factors and quadratic regression orthometric experiment was designed. The significant factors and fit equation was obtained and preliminary try was made to exsiccate the complicated relations which affect bonding properties.