Preservation of beech and spruce wood by allyl alcohol-based copolymers

Allyl alcohol (AA), acrylonitrile (AN), methyl methacrylate (MMA), monomers and monomer mixtures AA + AN, AA + MMA were used to conserve and consolida te Beech and Spruce. After impregnation, copolymerisation and polymerisatio n were accomplished by gamma irradiation. The fine structure of wood + poly mer(copolymer) composites was investigated by Scanning Electron Microscopy (SEM). It was observed that copolymer obtained from AA + MMA monomer mixtur e showed the optimum compatibility. The compressional strength and Brinell Hardness Numbers determined for untreated and treated wood samples indicate d that the mechanical strength of wood + copolymer composites was increased . It was found that the mechanical strength of the wood samples containing the AA + MMA copolymer was higher than the others. In the presence of P(AA/ MMA), at highest conversion, the compressive strength perpendicular to the fibres in Beech and Spruce increased approximately 100 times. The water upt ake capacity of wood + copolymer composites was observed to decrease by mor e than 50% relative to the original samples, and biodegradation did not tak e place. (C) 1999 Elsevier Science Ltd. All rights reserved.