Increasing Cold Tack of Polymeric Methylene Diphenyl Diisocyanate Resin with Partial Soy Flour Substitution

Partial substitution of polymeric methylene diphenyl diisocyanate resin with soy flour increases the cold tack of the resin to the level achieved by urea formaldehyde resin. The tack can be fine-tuned by adjusting the amount of soy flour added. The increase in tack is caused by the reaction of the isocyanate resin with the water contained in soy flour, as well as with hydroxyl and other groups present in soy flour components. The higher cold tack should increase the stability of pre-press mats, especially in particleboard manufacturing.