摘要
新型工艺胶乳法氯化天然橡胶(CNR)产品在干燥过程中会有HCl脱出,其脱出量对CNR的制备、性能等有一定的影响。采用电导法可连续测定CNR在干燥历程中脱HCl量及速率,这是研究CNR在低温下热降解行为的有效方法。用改进工艺的"胶乳法"制备出湿的CNR,并在一定温度下通入氮气进行干燥,在此历程中会发生脱氯化氢反应,其反应过程可分为诱导期、恒速期和低速期。文中使用Friedman法分析该过程在恒速期、低速期的反应动力学参数,其脱氯化氢反应分别为0级反应、1级反应,活化能分别为26.65,36.79 kJ/mol。在80℃以下对产品进行加热(或干燥),虽有少量HCl脱出,但并不会对产品质量造成影响。所以干燥温度应以低于80℃为宜。
Conductive detection can determine the HC1 loss amount and rate continuously during the drying process, which is an effective method to study the thermal-degradation behavior of chlorinated natural rubber （CNR） at low temperature. Fresh CNR, prepared by a new latex method, is dried at a certain temperature with the existence of nitrogen. During the drying process, the dehydrochlorination process happens, which can be divided into induction, constant rate and low speed stages. The kinetics parameters of constant rate and low speed periods were analyzed by Friedman equation. The results show that the dehydrochlorination processes are zero order reaction and first order reaction for constant rate and low speed periods respectively, and the corresponding activation energies are 26.65, 36.79 kJ/mol respectively. There is little HCI produced during the drying process at 80 %, but no negative effect on CNR quality. Therefore the ideal drying temperature is 80 °C below.
出处
《化学工程》
CAS
CSCD
北大核心
2012年第5期50-53,共4页
Chemical Engineering(China)
基金
国家自然科学基金资助项目(50873031)
广东省自然科学基金资助项目(9152402301000021)
关键词
电导法
氯化天然橡胶
脱氯化氢反应
动力学
conductivity method
chlorinated natural rubber
dehydroehlorination reaction
kinetics
