Abstract
The mechanical performance of polymers in voids and cellular parts of wood was studied for the following WPC systems; (a) PMMA (poly (methyl methacrylate)) -WPC polymerized by electron beam irradiation, (b) PMMA-WPC by injection of PMMA. Moreover, the change of molecular weight distribution (MWD) of PMMA in (a) was investigated. (1) E′ and E″ of wood increased by injection of PMMA, while they were not affected by PMMA in the cellular parts of (a) below 170°C. By the injection, the E″ peak of PMMA (85°C) shifted to heigher temperature side (120°C), while in the case of (a) the E″ peak of wood (230°C) shifted to lower temperature side (220°C) by PMMA in the cellular parts. (2) The molecular weight of extracted polymer by hydrolysis of the holocellulose increased with increasing moisture content of the system before irradiation. MWD of the grafted chains was narrower than that of the homopolymer. The above results suggest that the polymerization proceeded along the paracrystalline cellulose and hemicellulose matrix under irradiation.
