DETERMINATION OF DEGREE OF SUBSTITUTION OF SODIUM CARBOXYMETHYLCELLULOSE
DETERMINATION OF DEGREE OF SUBSTITUTION OF SODIUM CARBOXYMETHYLCELLULOSE
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DOI：
10.1021/ac60001a007
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发表时间：
1947-01-01
影响因子：
7.4
通讯作者：
DIEPHUIS, F
中科院分区：
文献类型：
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作者：
EYLER, RW;KLUG, ED;DIEPHUIS, F
Hollabaugh、Burt 和 Walsh (5) 发表了有关该产品用途和应用的完整评论和参考书目。 Brown 和 Houghton (1) 在另一篇评论中描述了一种基于电滴定法测定羧甲基纤维素轮胎酸形式取代度的方法。同一作者报道的另一种方法 (1) 涉及铜盐或铝盐的沉淀并测定沉淀物的金属含量。 Schmidt、Meinel、Jandebeur 和 Simson (7) 描述了一种测定纤维素中羧基的电导法，该方法与本文讨论的方法之一相关。 Sakurada (6)报道了三种确定取代度的方法，一种涉及用氢氧化钠进行电位滴定或电导滴定，另一种需要灰化钠盐，第三种包括用氢氧化钠滴定游离酸。由于这些程序都不能满足对适合控制目的的方法的需求，并且适用于不同取代度的钠盐的纯化和未纯化样品，因此开发了本文提出的方法。本文介绍了酸洗法、电导法和比色法三种测定羧甲基纤维素钠取代度的方法。然而，通过适当的修改，该方法也适用于游离酸形式。定量测定与其他材料的混合物中存在的羧甲基纤维素的量是可能的，但需要预先了解取代度。这些方法中的每一种都最适合某种类型的样品，尽管应用有时可能会重叠。
Hollabaugh, Burt, and Walsh (5) have published a complete review and bibliography on the uses and applications of this prod-uct. Brown and Houghton (1) inanother review described a method for determining degree of substitution of tire acid form of carboxymethylcellulose based uponelectrometric titration. Another method reported by the same authors (1) involves precipitation of the copper or aluminum salts and determination of the metal content of the precipitate. Schmidt, Meinel, Jandebeur, and Simson (7) describe a conductometric method for determining carboxyl in cellulose which is of interest in connection with one of the methods discussed in the present paper. Sakurada (6) reports three methods for determining substitution, one involving potentiometric or conductometric titration with sodium hydroxide, another requiring ashing the sodium salt, and the third consisting in titration of the free acid with sodium hydrox-ide. Since none of these procedures fulfilled the need for methods suitable for control purposes and applicable to both purified and unpurified samples ofthe sodium salt of varying degrees of sub-stitution, the methods presented here were developed. This paperdescribes three methods—acid-wash, conductometric and colorimetric—for determination of the degree of sub-stitution of sodium carboxymethylcellulose. With appropriate modifications, however, the methods would be applicable also to the free acid form. Quantitative determination of the amount of carboxymethylcellulose present in admixture with other ma-terials would be possible but would require previous knowledge of the degree ofsubstitution. Each of these methods is best adapted to a certain type of sample, although the applications may some-times overlap.