PREPARATION OF BINDERS FROM INEXPENSIVE BY-PRODUCTS FOR USE IN HIGH-PRESSURE PHENOLIC LAMINATES .2. BAGASSE LIGNIN AS AN EXTENDER IN PHENOLIC IMPREGNATING VARNISHES BASED ON PHENOL RESET AND PHENOLSOLVAN PITCHRESOL

The suitability of autohydrolysis bagasse lignin powder as a resin ext ender in phenol and pitch resol impregnating varnishes was evaluated. Various ratios of resol varnish to bagasse lignin were prepared and th eir performance as adhesives were tested on account oi their strength properties in 10-ply paper laminates. In all instances extension of th e varnishes with lignin resulted in a decrease of mechanical propertie s in this regard combinations oi pitch resol with lignin produced over all weaker systems than the phenol resol-lignin combinations, This was attributed largely to the substituted nature of pitch, which caused a reduction in resin functionality and limited the system is degree of crosslinking.