Synthesis And Application Research Of Polyvinyl Butyral

Polyvinyl butyral(PVB) is the essential material for laminated safty glass. With the development of autocar and architecture,PVB is used more and more. But it is easy to agglomerate while PVB being synthesized and it makes it hard for the post-treatment. To solve this problem, almost all the manufacturers use emulsifier to disperse PVB. But this will get another problem that the emulsifier must be removed, wasting plenty of water. Through research, we find that the non-uniform dispersion of butyraldehyde in PVA solution is the main reason of PVB agglomeration. Adding butyraldehyde to the PVA solution at the temperature of 40-60℃can ensure the uniform dispersion of butaraldehyde in PVA solution. HCl is dropped in when the temperature decrease to 15℃.Subsequently, powdered PVB can be got by controlling the rate of heating, the rate of stirring, the temperature of post-treatment and so on. The degree of acetalization of PVB synthesized using 10 times amplified equipment is 77.7%,and we prodece PVB films and laminated safty glasses using this PVB.PVB films are prepared by choosing four kinds of plasticizers to mix with self-made PVB resin respectively. The effects of the kind and amount of plasticizers on the PVB films are studied by the data of compatibility, tensile strength, breaking elongation, Tg and melt flow rate. The results indicate that polar plasticizers are more compatible with PVB resin. The compatibility of the four plasticizers with PVB resin are: DEHP>DOP>DBP>DOS. Within the compatibility, with the amount of plasticizer increasing, PVB films' tensile strength and Tg decrease, breaking elongation and melt flow rate increase. The plasticization of DEHP on PVB is best, when DEHP:PVB=1:5,PVB film's tensile strength increases to 30MPa,breaking elongation increases to 375.%.The haze of the laminated safety glass prepared by self-made PVB film≤0.41%,reaching the standard of industrial use. The results of the pummel and dropping ball impact strip experiments show that, comparing with the PVB manufactured by the SHANGHAI HAIDUN PLASTIC CO.LTD. ,the adhesion of safe-made PVB with glass is eligible.