疏水改性聚丙烯酸溶液的流变特性研究

Study on the rheology behavior of hydrophobically modified poly(acrylic acid) solution

本文通过沉淀聚合制备了具有不同主链结构的疏水改性聚丙烯酸(HMPA),由Huggins方程确定了HMPA在溶液(水,盐/水,醇/水)中的特性粘数[η]和Huggins常数KH,采用流变学法研究了HMPA溶液的疏水缔合行为和流变特性。研究表明,HMPA溶液具有典型的剪切变稀行为,主链结构对HMPA溶液的缔合行为和流变特性有显著影响。主链含有疏水链段的HMPA在乙二醇/水溶液中形成类似弹性体的凝胶网络结构,具有较大的活化能,其表观粘度具有明显的温度敏感性。

Hydrophobically modified polyacrylic acids （HMPA） with different backbone composition were synthesized by precipitation polymerization. The association behavior and rheology properties of HMPA solution were studied. The HMPA solutions show typical shear thinning behavior. A hydrophilic segment allows solubility of the polymer in solution and a hydrophobic segment such as ethyl acrylate in backbone promotes intramolecular and intermolecular association with other hydrophobes,leading to the formation of a network structure. Apparent viscosity of HMPA in ethylene glycol-water solution reduces as temperature increases. The composition of polymer backbone and the hydrophobieity of the polymer system are responsible for the rheologieal changes in solution.