FIBER ACTIVATION AND SUBSEQUENT CO-POLYMERIZATION

High temperature refined thermo-mechanical pulp (MDF fibre) was dried, extracted with neutral organic solvent and reacted with a series of electrophilic reagents (glycidyl methacrylate, maleic anhydride and succinic anhydride). The adducts formed were characterised by infra-red spectroscopy and further reacted in a hot press with methyl methacrylate in the presence of a free radical initiator (benzoyl peroxide). Well conformed board were produced by the process. Samples of these boards were ground to a fine flour, extracted with acetone/toluene to remove poly (methylmethacrylate), PMMA homopolymer and again characterised by infra-red spectroscopy. The spectral evidence suggests that in those boards formed using fibre modified with unsaturated reagents (glycidyl methacrylate and maleic anhydride), some copolymerisation between fibre and PMMA occurs. Where the adduct is saturated (succinic ester), bonding appears to be substantially by physical interaction. Those products formed with the involvement of chemical interaction may have enhanced resistance to deterioration in moist environments.