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Cellulose powder and cellulose pellets obtained by pressing the microcrystalline powder were studied using differential scanning calorimetry (DSC), differential thermal analysis (DTA), and thermal gravimetry (TG). The TG method enabled the assessment of water content in the investigated samples. The glass phase transition in cellulose was studied using the DSC method, both in heating and cooling runs, in a wide temperature range from -100 to 180 °C. It is shown that the DSC cooling runs are more suitable for the glass phase transition visualisation than the heating runs. The discrepancy between glass phase transition temperature T g found using DSC and predictions by Kaelbe's approach are observed for “dry” (7 and 5.3% water content) cellulose. This could be explained by strong interactions between cellulose chains appearing when the water concentration decreases. The T g measurements vs. moisture content may be used for cellulose crystallinity index determination.

The properties of methyltrimethoxysilane-treated, waterlogged archeological elm wood were studied by magnetic resonance imaging and nuclear magnetic resonance (NMR) methods. The spatially resolved proton density images, spin–spin relaxation profiles, proton NMR spectra, and self-diffusion coefficients of the preservative agents were measured during drying. The resolution of the data allowed for the differentiation between the early and late wood areas of the elm wood and determination of the shrinkage of the sample in the tangential and radial directions, and it showed the different dynamics of methyltrimethoxysilane (MTMS) in the lumen cells of both early and late woods. The NMR spectra indicated that the MTMS, after rapid evaporation of ethanol, is bound to the wood. Identical measurements were also taken for the archeological elm wood treated with polyethylene glycol (PEG) and for an untreated wood sample. From the results, it can be concluded that MTMS showed significantly higher stability against shrinkage when compared to PEG. Therefore, it may be considered as an alternative preservative for archeological wood.

Nuclear magnetic relaxation processes in methyl cellulose (MC) and hydroxypropylmethyl cellulose (HPMC) were studied by proton spin-lattice NMR relaxation. The proton relaxations were measured in the temperature range 90–420 K at 90 MHz. At low temperature the proton spin-lattice relaxation is caused by the modulation of the methyl proton-proton dipole-dipole interactions by the reorientation of the methyl groups. In this temperature range the spin relaxation vs. temperature data were interpreted with the model of dynamical inequivalence of methyl groups: two in MC and three in HPMC. The dynamical parameters were calculated for each of these groups. The segmental motion of the MC and HPMC chain via the glucosidic bond which corresponds to the local chain motion of these polymers is the dominant mechanism of the proton spin-lattice relaxation time above 250 K.