Associative polymers based on acrylic acid and n-butyl methacrylate were synthesized via precipitation polymerization in pressurized carbon dioxide. Physicochemical characterization confirmed BMA incorporation and good reaction yields (>67.1 mol%). Size exclusion chromatography showed bimodal polymer molar mass distribution with distinct average molar masses. Rheological properties of aqueous polymer solutions were assessed under varying pH, ionic strength, and salt concentrations and demonstrated increased viscosity with higher n-butyl methacrylate content, attributed to hydrophobic associations. The apparent viscosity of the synthesized polymers was strongly influenced by the ionic strength of the aqueous solutions.

中文翻译：

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高压单流体引发下丙烯酸 + 甲基丙烯酸丁酯在超临界二氧化碳中的相界和共聚


通过在加压二氧化碳中沉淀聚合合成基于丙烯酸和甲基丙烯酸正丁酯的缔合聚合物。物理化学表征证实了 BMA 掺入和良好的反应产率 （>67.1 mol%）。尺寸排阻色谱显示双峰聚合物摩尔质量分布，具有不同的平均摩尔质量。在不同的 pH 值、离子强度和盐浓度下评估了聚合物水溶液的流变特性，并证明甲基丙烯酸正丁酯含量越高，粘度就越高，这归因于疏水键合。合成聚合物的表观粘度受水溶液离子强度的强烈影响。