Estimation of the physical characteristics of some natural compounds

Various physical characteristics of the fragments of repeating units of some natural high-molecular-mass compounds were calculated. The following characteristics were studied: the glass transition temperature, the temperature of the onset of intense thermal degradation, the dielectric constant, the index of refraction, the total energy of intermolecular interaction and its components (the weak dispersion interaction energy, the dipole-dipole interaction energy, and the hydrogen bonding energy), the permeability for different gases, etc. Special attention was paid to the effect of hydrogen bonding, both between different chains and within one chain, on the glass transition temperature, the molecular mass at which the rubbery state is manifested, and some other properties of natural polymers-hemicelluloses and fragments of their structure. Verification of the obtained results on 1,4-β-D-glucomannan samples showed satisfactory agreement between the calculated and experimental values.