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本文制备了一系列高分子量的聚丙烯酸和甲基丙烯酸高级酯,研究了这些聚合物的分子量及其分布,侧基大小和溶液浓度对煤油溶液的流变性、减阻性和抗剪切性的影响。实验证明,这些高级酯煤油溶液都是假塑性流体,流动行为可用幂律描述:τ=k_γ~n;溶液的湍流摩擦系数(f)、雷诺数(R_e)和减阻触发时的雷诺数(R_(eo))之间的关系为:(?)。发现减阻百分率(DR)先随壁切应力(τ_w)增大而增加,超过一定的壁切应力(τ_(wm))后,DR 逐渐下降。DR 随分子量增大而增大,当分子量超过一定值后,DR 达到一个极限值(DR_m)而不再增大。DR_m 随浓度增加而增加。τ_(wm)基本上与浓度无关。在低速下,分子量分布较宽的样品具有较高的 DR 值。在湍流中,聚合物的抗剪切性随侧基增大和溶液浓度的提高而增强。
In this paper, a series of high molecular weight polyacrylic acid and methacrylic acid esters were prepared. The molecular weight and distribution of these polymers, the size of pendant groups and the concentration of solution on the rheological, drag and shear resistance influences. Experiments show that these advanced ester kerosene solutions are pseudoplastic fluids. The flow behavior can be described by power law: τ = k_γ ~ n; the turbulence friction coefficient (f), Reynolds number (R_e) and Reynolds number R_ (eo)) the relationship between: (?). It was found that the percentage of drag reduction (DR) increased with the increase of wall shear stress (τ_w) first and then decreased gradually after a certain wall shear stress (τ_ (wm)). DR increases with the increase of molecular weight, when the molecular weight exceeds a certain value, DR reaches a limit (DR_m) without increasing. DR_m increases with increasing concentration. τ_ (wm) is essentially independent of concentration. At low speeds, samples with broad molecular weight distribution have higher DR values. In turbulent flow, the shear resistance of the polymer increases with increasing pendant groups and increasing concentration of the solution.