疏水改性聚乙烯醇的黏度行为

以２，４ 二异氰酸甲苯酯作交联剂将十四醇、十八醇作为疏水基引入聚乙烯醇分子中，合成疏水性缔合型增稠剂。当疏水基的摩尔分数仅为０．２５ ％ 时，聚乙烯醇水溶液的黏度就会迅速增高，且水溶液的耐盐能力大大增加。以摩尔分数为０．２５％ 的十八醇疏水基改性聚乙烯醇后，在ｗ（ＮａＣｌ）＝ ６％ 溶液中仍保持黏度的稳定性。

Viscometic Behaviour of Hydrophobically Modified Poly(vinyl alcohol)

Hydrophobically moditied poly(vinyl alcohol)was obtained by introducing a small amount of higher alcohol on the hydroxy groups of the polymer in methyl pyrrolidone utilizing toluene 2,4 di iso cyanate as cross linking agent.This modified polymer though bearing only a low content of hydrophobic group (i.e.0.25%) exhibited very high thickening effect.The viscosity of its aqueous solution still remained on addition of NaCl.Solution of poly(vinyl alcohol) bearing 0.25 % octadecyl group in pure water presented a somewhat higher viscosity than that of the unmodified poly(vinyl alcohol) and the viscosity remained unchanged even in 6% NaCl solution.