标准摘要
[中文适用范围]： 羟基在吡啶溶液中被邻苯二甲酸酐酯化。 过量的邻苯二甲酸酐被用于中和的氢氧化钠溶液中含有的水水解。 在酯化过程中出现的酸度和在水解过程中形成的邻苯二甲酸的酸度在酚酞作为指示剂的存在下用氢氧化钠溶液中和。 根据滴定空白溶液和测试溶液所用氢氧化钠溶液的体积之差计算羟值。 [外文原描述]： The hydroxyl groups are esterified by phthalic anhydride in pyridine solution. The excess of phthalic anhydride is hydrolyzed with water containing in the sodium hydroxide solution used for the neutralization. The acidity which appears during the esterification and of the phthalic acid formed during the hydrolysis is neutralized by sodium hydroxide solution in the presence of phenolphthalein as indicator. The hydroxyl value is calculated from the difference between the volumes of sodium hydroxide solution used for the titration of the blank and of the test solution.
英文名称Non-ionic surface active agents — Polyalkoxylated derivatives — Determination of hydroxyl value — Phthalic anhydride method