Study Of Normal Temperature Fast-solidify Emulsion Timber Adhesive

This research subject's objective is increase production efficiency and improve bonding strength of laminated finger-joint board's processing enterprises.The subject is proposed copolymerization modification to lumber emulsion adhesive of normal temperature solidification.Through emulsion copolymerization modification,introduce a variety of active functional groups,the introduced another group of PAPI can rapid with active functional groups and wood surface itself with active hydrogen groups befallen reaction,form cross-network-like structure,thus greatly improve the solidify speed and bonding strength,the results show that:(1) The selecting of copolymerize monomers,polymerize time,polymerize temperature,agitating rate,the dosage of emulsifier and initiator have great influence to vinyl acetate-acrylate emulsion adhesive's performance;select acrylic acid series monomer participate in copolymerize,polymerize time 4～5 hour,polymerize temperature 80℃,agitating rate 180～240r/min and the dosage of emulsifier and initiator relative to polymeric monomer total 3%and 0.5%,under these conditions,the vinyl acetate-acrylate emulsion adhesive have steady performance.(2) It also analyzes the particle size,the emulsion particles' distribution,glass transition temperature and the polymerization of the emulsion adhesive by TEM,DSC and FTIR,and consider the cost of production and the bonding strength ect other factors,final choice vinyl acetate copolymerize emulsion to be normal temperature fast-solidify two component timber adhesive's main components.(3) At the normal temperature,the addition amount of PAPI has the most influential effect on bonding property,the following is pressing time,the addition amount of starch and pressure has little effect.Considering of the product quality and the producing cost,the optimum process of glulam is:the addition amount of PAPI 15%,pressing time 15 min,the addition amount of starch 5%,specific pressure 2MPa.The bonding properties and the water resistance of the glulam prepared by this process are excellent,which can satisfy the JAS(Japan glulam standard) and indoor standard of non-structural glulam,that has a wide application prospect.