CHEMICALLY MODIFIED WOOD - SOLID-STATE CROSS-POLARIZATION MAGIC-ANGLE SPINNING NMR-SPECTROSCOPY

Our investigations on birch, spruce, aspen, beech and eucalyptus wood show that solid state cross polarization/magic angle spinning nuclear magnetic resonance (CP/MAS NMR) spectroscopy can be used to check small changes in composition by treating in situ solid wood with various chemical agents. Mechanical strength data correlate with changes in intensities of NMR bands showing the crystallinity of fibers and especially with changes in T1 relaxation data. The advantages of NMR and Fourier transform infrared spectroscopy (FTIR) methods as tools for analysis of chemical and mechanical properties of solid wood are discussed in terms of current viscoelastic theories.