配合胶乳和硫化胶乳胶膜干燥历程及交联密度比较研究

The Comparison Study of Drying Kinetics and Cross-linking Desity of Formulated and Prevulcanized Natural Latex Films during Drying

采用热风干燥方法进行配合胶乳和硫化胶乳胶膜的干燥实验,研究了两种天然胶乳胶膜的干燥动力学过程及干燥过程与橡胶分子链交联密度的关系。结果表明,配合胶乳膜干燥的活化能Ea1=31.4kJ·mol-1,硫化天然胶膜的干燥活化能Ea2=63.6kJ·mol-1,配合胶乳膜较硫化胶乳膜易于干燥;在相同条件下,配合胶乳膜的交联密度始终低于硫化胶乳膜。配合胶乳膜和硫化胶乳膜的干燥过程与硫化过程并不同步,过度的加热干燥会导致交联密度的降低。

In order to investigate the differences of drying kinetics and the relationship between drying process and cross-linking density of formulated natural latex film and prevulcanized natural latex film during drying, mass loss and swelling methods were used in the experiments. The results showed that the drying activation energy of formulated natural latex film and prevulcanized natural latex film were 31.4 kJ·mol^-1, and 63.6 kJ·mol^-1, respectively, that was, formulated natural latex film was more easily to be dried than prevulcanized natural latex film. In the same drying conditions, the cross-link density of formulated natural latex film was lower than that of prevulcanized natural latex film. No matter formulated natural latex film or prevulcanized natural latex film; the drying process and vulcanization process were not synchronous. Excess drying may caused the reduction of the cross-link density.