Search

Synthesized cellulose pelargonates, tridecanoates, valerates, and acetovalerates of various molecular weights are studied in chloroform, dioxane, and tetrachloroethane solutions by the methods of isothermal translational diffusion, sedimentation velocity method, flow birefringence (dynamooptical Maxwell effect), viscometry, and equilibrium electric birefringence (Kerr effect). The equilibrium polymer rigidities are determined and the role of the solvent and temperature in the formation of the conformational characteristics of the macromolecules under study is analyzed. The values of the intrinsic optical anisotropy of the monomeric units of the studied cellulose esters are experimentally determined. The contribution of the side chains to the optical anisotropy of the macromolecules of cellulose esters with aliphatic substituents is analyzed. The results obtained in this study are compared with the data on the cellulose esters with the aliphatic side substituents studied earlier. For the studied samples, the values of the longitudinal components of the monomeric unit dipoles in a nonpolar solvent are estimated. [ABSTRACT FROM AUTHOR]

The influence of weight-average molecular mass M on the maximal width of a conducting layer h of polysterene, polymethylmethacrylate, and polyamidine films was investigated. It was shown that h increases in proportion to M for all investigated polymers. It points to the fact that the h value is defined by the macromolecular coil size. [ABSTRACT FROM AUTHOR]

Cellulose tridecanoates of various molecular weights were synthesized, and their characteristics in chloroform and tetrachloroethane solutions were studied by methods of translational diffusion, velocity sedimentation, flow birefringence (Maxwell's method), and viscometry. The effects of solvent and temperature on the conformational characteristics of the macromolecules under consideration were examined. The anisotropy of the monomeric unit of cellulose tridecanoates was studied, and the contribution of pendant chains to the optical anisotropy of macromolecules of cellulose esters with aliphatic substituents was analyzed. [ABSTRACT FROM AUTHOR]

Newly prepared cellulose pelargonate samples of various molecular weights were studied in dioxane and chloroform solutions by isothermal translation diffusion, high-speed sedimentation, flow birefringence (Maxwell effect), electric birefringence (Kerr effect), and viscometry. The conformational, hydrodynamic, optical, electrooptical, and dynamic characteristics of the polymer were determined. [ABSTRACT FROM AUTHOR]