Optical, morphological, thermal, mechanical, and fungal characterization of wood polymethyl methacrylate composites

摘要

Impregnation polymerization of methyl methacrylate (MMA) into blackberry wood, at a series of methyl methacrylate concentrations ranging 1.0-3.0 M, in presence of benzoyl peroxide (0.02 M) in methanol, at 75 +/- degrees C, afforded wood polymethyl methacrylate composites (WPCs). Photoacoustic (PA) spectra of pure polymethyl methacrylate (PMMA), wood, and WPCs have been recorded in the wavelength region 250-400 nm using a single beam PA spectrometer; PA spectra of pure PMMA show absorption at 270 nm, due to n-pi transition of carbonyl linkage of the ester group. UV-VIS spectra in chloroform for PMMA and WPC indicate maximum absorptions at 275 and 280 nm, respectively, whereas wood does not indicate any sharp absorption. PA spectra of wood and WPC show a strong band at 270 nm, which may be due to the presence of lignin. The presence of PMMA loading into wood was qualitatively ascertained through scanning electron microscopy and qualitatively through PA spectroscopy. Wood indicates a maximum load failure in terms of compression strength, charpy, and izod impacts at 3.99 x 10(7) N/m(2) , 23.91, and 7.35 Nm, respectively. Impregnation of PMMA enhanced the strength of wood under compression and impact with MMA concentrations. Thermogravimetric analysis (TG), differential scanning calorimetery (DSC), and differential thermogravimetry (DTG) data in air indicate that thermo oxidative stability of wood due to PMMA impregnation was significantly improved. PMMA impregnation into wood imparts improved resistance to water, alcohol-benzene media, sodium hydroxide (10%), ether, and towards a white rot fungus Coriolous versicolor .