| abstract |
The present invention provides wood adhesive binder compositions comprising a naturally occurring protein component, e.g. soy flour, and an oxazoline-functional group containing polymer or resin component, the two components in a solids weight ratio of from 60:40 to 98:2. As formulated, the compositions may comprise from 40 to 98 wt.% of the naturally occurring protein component, preferably, 50 wt.% or more. Preferably, the wood adhesive binder further comprises lignins or lignosulfonate. Where the wood adhesive binder compositions comprise lignins or lignosulfonates, they remain more fluid and workable at a higher pH such as, for example, 4.5 or more. Any of the compositions may be formulated with one or more in situ acid generator compound to insure more rapid cure on heating or pressing. The binder enables the provision of mechanically sound, low cost and biodegradable composites, such as, medium density fiberboard (MDF). |