无机离子对疏水缔合聚合物溶液行为的影响

Influence of Inorganic Ions on Solution Behavior of Hydrophobically Associating Polymer

采用光散射技术研究了无机离子对疏水缔合聚合物S308分子尺寸的影响,探索了疏水缔合聚合物S308分子尺寸随聚合物浓度、溶液矿化度的变化,同时利用流变技术表征了S308在盐溶液中的流变性。结果表明,分别用1 mol/L的Na Cl、KCl、NH4Cl盐溶液和0.01 mol/L的Ca Cl2溶液配制浓度为0.05 g/L的聚合物溶液,在不同阳离子对应聚合物溶液中聚合物分子尺寸按大小排序为:Rh(Ca2+)<Rh(K+)≈Rh(NH4+)<Rh(Na+),不同阳离子对聚合物分子尺寸的影响程度排序为Ca2+>K+≈NH4+>Na+。固定溶液中Na+含量为1 mol/L,分别采用Na Cl、Na2CO3、Na2SO4盐溶液配制浓度为0.05 g/L的S308溶液,在Na Cl溶液中的聚合物Rh仅为217 nm,而在Na2CO3和Na2SO4溶液聚合物Rh分别为277 nm和238 nm,说明在阳离子种类、含量相同时,相对于一价阴离子溶液,在高价阴离子溶液中聚合物的分子尺寸相对较大。在不同一价盐溶液中,溶液的表观黏度基本随分子尺寸变大而逐步提高。另外,随矿化度升高,S308的分子尺寸先上升后下降,均方回旋半径与流体力学半径的比值Rg/Rh逐渐减小,分子构型逐渐卷曲。

The influence of inorganic ions on the molecular size of hydrophobically associating polymer S308 was investigated by light scattering technology. The dependence of the molecular size on polymer concentration and salt content was also studied.Meanwhile,we also tested the rheological properties of S308 in salt solvent. The results showed the Rhof the S308 solutions prepared by Na Cl、KCl、NH4Cl solutions with the concentration of 1 mol/L and Ca Cl2 solution with the concentiaon of 0.01 mol/L,respectively,was arranged as follows,Rh(Ca2 +)< Rh(K+)≈ Rh(NH4+)< Rh(Na+). In other words,the order of the influencing capacity of these cations was as follows,Ca2+>K+≈NH4+>Na+. When the Na+content of solution used to prepare the polymer solution was determined to be of 1 mol/L and the concentration of S308 was of 0.05 g/L,the Rhof the polymer in the Na Cl,Na2CO3 and Na2SO4solutions was of 217 nm,277 nm and 238 nm,respectively,indicating that polymer molecular size tended to be larger in solvent containing high valence anions than in solvent containing monovalent anions when the solvent contained the same kind and amount of cations. In different salt solvents,the apparent viscosity of the polymer solution basically increased with the increase of the molecular size. Besides,with the salt content increasing,the molecular size of S308 increased at first and then went down,and the ratio of gyration radius to the hydrodynamic radius(Rg/Rh)decreased gradually,indicating the polymer chain transformed from stretch to curl.