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The dynamic surface elasticity of aqueous solutions of poly(N-isopropylacrylamide) (pNIPAM) has been measured by the oscillating barrier and capillary wave methods as a function of time and concentration. While the real and imaginary parts of the surface elasticity almost did not change with the concentration, their kinetic dependencies proved to be nonmonotonic. Simultaneous measurements of the film thickness and adsorbed amount by null-ellipsometry showed that the pNIPAM adsorption can be divided into two steps corresponding to the formation of a concentrated narrow region close to the air phase and a region of tails and loops protruding into the bulk liquid. The local maximum of the elasticity can be observed in the course of the first step when the adsorbed macromolecules do not form long loops and tails. The results are in agreement with recent data on the nonequilibrium surface properties of solutions of other nonionic homopolymers and the theory of dilational surface viscoelasticity.

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Several series of thermotropic liquid-crystalline polyesters, based on Cchlorwarbonyl phenyl esters of aromatic dicarboxylic acids (1 -4) and phenols or aliphatic diols, were synthesized and studied by polarizing microscopy and differential scanning calorimetry (DSC). A relationship between geometry of mesogenic moiety and stability of mesophase formed by the polymers was established. The effect of both the length and chemical structure of the flexible fragments on the mesomorphic properties was revealed for polyesters obtained from aliphatic diols. Several polymers were obtained whose temperatures of transition into the liquid crystalline state were found to be below 100 "C. Two series of low-molecular-weight liquid-crystalline compounds were synthesized to compare their properties with those of the polymers of similar structure. Most of the low-molecular-weight analogs have not been described so far. They predominantly form a smectic type mesophase.

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Two series of conjugates of dextran and antioxidants from the class of sterically hindered phenols were prepared. The conjugates were characterized by the substitution degree of glycoside units, solubility in different solvents, intrinsic viscosity. The investigation of radical scavenging activity (RSA) of conjugates was carried out in their reactions with two free radicals — 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) and sodium salt of 2,2‐diphenyl‐1‐picrylhydrazyl sulfonic acid (DPPH‐salt). The usage of water soluble DPPH‐salt enabled to estimate the RSA of the conjugates in water. It was shown that the rate constants of interaction of the DPPH‐salt and the conjugates were 10–30 times higher than this value for low‐molecular analogue of phenoxan. High RSA of the conjugates in water can be explained by large solvation shell formed due to high content of hydroxy groups in dextran.

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