Soy Flour Substitution in Polymeric Diphenylmethane Diisocyanate Resin Reduces Press Platen Sticking

Partial (10% to 30%) substitution of soy flour in polymeric diphenylmethane diisocyanate (pMDI) resin substantially reduces platen sticking during hot-pressing of particle mats. Adding the soy flour to a fixed dose of pMDI (instead of substituting it) reduces platen sticking to an even greater extent. The soy decreases the tack of cured pMDI, thereby reducing the propensity of resinated particles to transfer to the platen. The tack reduction effect of soy on cured pMDI contrasts with its effect on uncured pMDI, where the cold tack is increased.