白乳胶中甲醛含量测定方法研究

Study on mensurating methods of formaldehyde content in white latex

采用化学滴定法(碘量法)和乙酰丙酮分光光度法对五种市售白乳胶中甲醛含量进行测定与比较,并设计出一种可以快速简便测定甲醛含量的定性方法——希夫试剂比色法。结果表明:采用碘量法和分光光度法测定白乳胶中游离甲醛含量,两者测试结果相近,偏差在2.6%～7.0%之间;希夫试剂比色法操作简单、快速,但误差较大,可以用作快速定性判定样品中是否含有游离甲醛;在其它条件保持不变的前提下,测试温度越高,白乳胶中游离甲醛含量的测试结果越大。

The formaldehyde contents in five kinds marketed white latexes were mensurated and compared by chemical titration（iodimetl7） and acetylacetone spectrophotometry. A Schiff reagent colorimetry as simpler and faster qualitative mensurating methods of formaldehyde content was devised. The results showed that two mensurating results of free formaldehyde contents in white latexes were similar by iodimetry and acetylacetone spectrophotometry, the deviation of two mensurating results was between 2.6% and 7.0%. The Schiff reagent colorimetry as a qualitative method can fast judge samples with or without free formaldehyde because its operation is simpler and faster,but error is bigger. The mensurating temperature was higher,the mensurating result of free formaldehyde content in white latex was bigger when other conditions were unaltered.