A procedure is proposed for preparing polyvinyl alcohol fiber with increased water absorption by acetalization of a freshly formed fiber with dialdehyde-containing polyvinyl alcohol fiber. The fiber characteristics were determined in relation to the acetalization conditions. 相似文献
Photochemical reduction of ions of d metals (Mo and W) in the presence of polyvinyl alcohol depends on the acidity of the solutions and on the composition of the gas medium. The effect of UV radiation on the solubility of the components in the system polyvinyl alcohol-ammonium molybdate-water was studied. The mechanism of photochemical reactions and the structure of polymer-salt complexes were discussed. Mesomorphic formations similar to liquid-crystalline arise in the polymer-salt systems due to the rigidity induced in macromolecules of the water-soluble flexible-chain polymer by complex formation with inorganic polyions. 相似文献
MD studies of liquid isopropyl alcohol and melts of short poly(vinyl alcohol) (PVA) oligomers are described. The specific volume was found to depend inversely on the number N of repeat units. If the chain length is enhanced, the viscosity of the PVA melt increases and the peaks in the radial distribution function become sharper. Additional peaks that appear in melts of PVA chains are of pure intramolecular origin. The calculated radius of gyration was found to depend on the number of formula units via . The orientation correlation functions showed that all molecular vectors of PVA melts with chain lengths N = 1, 2, 3 relax completely within a few nanoseconds. The relaxation times for the O H bond vector as obtained via the Kohlrausch‐Williams‐Watts expression showed an exponential dependence on the number of repeat units.
