聚乙烯醇水溶液的粘度行为研究

STUDY ON VISCOMETRIC BEHAVIOR OF AQUEOUS PVA SOLUTION

研究了不同浓度聚乙烯醇水溶液的粘度行为。以恒定外加盐稀释法，用乌氏粘度计测得不同外加盐浓度聚乙烯醇稀溶液的粘度，计算溶液的特性粘数和Ｈｕｇｇｉｎｓ常数。获得聚乙烯醇水溶液的临界交叠浓度及凝胶转变的热函。确定了不同聚乙烯醇和外加盐浓度下聚乙烯醇水溶液的溶胶－凝胶转变的边界条件。结果表明，聚乙烯醇水溶液粘度对外加盐或ｐＨ值较不敏感，从而使聚乙烯醇作为一种用于恶劣环境下三次采油的水溶性高分子将具有广阔的应用前景。

Aqueous poly(vinyl alcohol) solution of various concentrations were investigated. With the method of dilution in constant concentration of added salt, viscosities of PVA in aqueous solution containing added salt were measured at 25±0.1 ℃ in an Ubbelohde Viscometer. Intrinsic viscosities and Huggins constants of aqueous PVA solution with different concentrations of added salt were calculated. The critical concentratin for chain overlap and the enthalpy of gel transition of aqueous PVA solution were obtained. Dependence of sol gel transition on different concentrations of PVA and added salt were also determined. From the experimental results, the viscosity of aqueous PVA solution is less sensitive to added salt and variation of wide range of pH. Thus, PVA is a promising water soluble polymer in the tertiary oil recovery under hostile oilfield environment.