Research on Plywood by Flame Retardant and Aldehyde Free Adhesive

In order to solve the problem of poor fire resistance of waterborne polymer-isocyanate (API) adhesive, the flame retardant improvement of API adhesive was carried out to improve the flame retardancy of API adhesive. Through the modification of polyvinyl alcohol, the main agent in API adhesive, the hydroxyl functional group of polyvinyl alcohol molecular chain was reacted with phosphoric acid molecule, and phosphate polyvinyl alcohol was obtained by esterification.(PPVA), changed inorganic filler into flame retardant mg-Al hydrotalcite (LDH), in API adhesive, which had synergistic flame-retardant effect and can be synergistically flame retardant with polyvinyl alcohol phosphate. In this study, the composition percentage of flame retardant modified API adhesive was as follows: polyvinyl alcohol phosphate (PPVA) instead of polyvinyl alcohol (PVA) accounted for 70% of the main agent, latex (SBR) accounted for 30% of the main agent, curing agent (M-PDI) accounted for 10% of the main agent, and hydrotalcite (LDH) as an inorganic filler accounted for 30% of the main agent. The experimental results showed that the bonding strength of flame retardant modified API adhesive plywood can meet the requirements of II plywood, reduce the combustion heat release and smoke release of plywood, and had the effect of flame retardant and smoke suppression.