双氧水对聚苹果酸脱色效果探究

Study of Decoloration Effect on Poly Malic Acid by H_2O_2

研究了双氧水对聚苹果酸脱色及其对聚苹果酸的影响,确定最佳脱色工艺。结果以脱色效果、聚苹果酸损失率和分子量为指标,在单因素筛选的基础上,采用正交试验法对脱色工艺进行优选,并对聚苹果酸进行结构表征。最终确定脱色最佳工艺为:双氧水添加量15%(体积比)、温度60℃、时间4 h、p H 10;红外光谱和核磁共振结果显示双氧水处理后部分聚苹果酸氧化。且纯度比未用双氧水处理时要高,可以选用此种方法进行快速有效的脱色。

The objective of this study was to discuss the decolorization effect on poly malic acid by H2O2 and determine the optimal bleaching process.The decolorization effect , loss ratio and molecular weight of PMLA were used as indexes. Based on the single factor experiment , the orthogonal design was applied to select the optimal condition for the decolorization of PMLA.The apparent structure of PMLA was determined under this optimal condition. As a result, the optimal extraction conditions were as follows：the volume addition of H2O2 was 15 %, the temperature was 60℃,the bleaching time was 4 hours and the bleaching pH was 10. The result of FT-IR and HMR showed that the PMLA dealt with H2O2 was partly oxidized. The purity of PMLA was higher than untreated with H2O2. This kind of method can be chosen for fast and efficient decolorization.