FUNDAMENTAL STUDIES OF PHENOL-FORMALDEHYDE (PF) I POLYMERIC DIPHENYLMETHANE DIISOCYANATE (PMDI) HYBRID ADHESIVES

摘要

Phenol-formaldehyde (PF) and polymeric diphenylmethane diisocyanate (pMDI) are the most common exterior grade thermosetting adhesives in the wood products industry. There has been an interest in combining these two adhesives; it is anticipated that the combination will benefit from their positive qualities, while also neutralizing some of the negative ones (e.g., relatively slow cure rate for PF and high cost for pMDI). Several applications of PF/pMDI hybrids in the manufacture of particleboard and plywood have been reported (US Patents 4209433, 4268649, 5407980; Pizzi, et al 1993, etc.), however, a fundamental understanding of this system is lacking. A better understanding of this system will help determine the potential value of this adhesive to the wood products industry.