羧甲基羟丙基纤维素混合醚耐盐性研究

The salt Resistance of Carboxymethyl Hydropropyl Cellulose Ethers

通过X-射线衍射、红外吸收光谱和浊度测定,研究了羧甲基羟丙基纤维素(CMHPC)结构和溶解性能的关系。结果表明,CMHPC的溶解性能归因于纤维素中导入了羧甲基和羟丙基两种亲水基团,以及因导入这两种基团所引起的纤维素消晶作用。CMHPC不仅能溶于浓的NaCl溶液,而且能溶于二价碱土金属盐溶液。通过溶液折射率和盐粘比值的测定,研究了金属盐对CMHPC水化的影响。结果表明,金属离子的去水化能力顺序是:Na^+<Mg^(2+)<Ca^(2+)<Sr^(2+)<Ba^(2+)。而CMHPC抗盐的去水化能力随MS值增大而增强,随DS值增大而减弱。一般来说CMHPC的盐粘比值大于1。

The relation between strutucre of CMHPC and its solubility has been demonstrated with X-ray diffracrogram, infrared absorption spectra and turbidity measurements It has been shown that solubility of CMHPC is attributed to leading, two hvdrophilic groups,carboxymethyl and hydropropyl,into cellulose and to crystal erasing caused by leading of both groups into cellulose CHMPC can solved not only in concentrated NaCl salt solutions,but also in concentrated solutions of divalent metal salts.The effects of salts on the hydration of CMHPC have been studied with measurements of refrective, indexes and salt viscosity ratio (SVR) . The results show that the order of the dehydration ability of metal salts is Na^(2+)<Mg^(2+)<Ca^(2+)<Sr^(2+)<Ba^(2+). The ability of CMHPC against dehydration of divalent metal sults increases with increasing MS value and decreases with increasiug of DS value. The SVR valus of CMHPC is generally more than 1.