摘要
对微波辐射乳酸熔融缩聚反应动力学进行研究,考察微波功率、催化剂及辅助加热介质等对反应级数和反应速率常数的影响,并与传统加热法进行了比较.结果表明,在微波热效应和非热效应共同作用下,反应速率常数明显增大,且速率常数随着微波功率的增加而增大,但微波辐射不改变反应在传统加热条件下原有的反应级数,乳酸自催化熔融缩聚反应为三级反应,在外加酸催化下乳酸熔融缩聚反应为二级反应;在体系中加入碳化硅作为辅助加热介质对反应级数无改变,但可使反应速率常数提高约20%.
The chemical reaction kinetics of melt polycondensation of lactic acid under microwave irradiation was studied. The effects of microwave power, catalyst and assisted - heating medium （SiC） were investigated. The chemical kinetic parameters under microwave irradiation were compared with those under conventional heating. It was found that, with the co-effects of thermal effects and nonthermal effects of microwaves, the reaction rate constant under microwave irradiation was enhanced obviously and increased with the microwave power increasing; microwave irradiation had no changes on the original reaction order under conventional heating; the orders of self-catalytic polycondensation and acid-catalytic polycondensation were 3 and 2 respectively; the addition of SiC as assisted - heating medium during the reaction had no effects on reaction order, but made the reaction rate constant increase about 20%.
出处
《哈尔滨工业大学学报》
EI
CAS
CSCD
北大核心
2006年第8期1330-1332,1339,共4页
Journal of Harbin Institute of Technology
关键词
微波辐射
乳酸
熔融缩聚
反应动力学
microwave irradiation
lactic acid
melt polycondensation
chemical reaction kinetics
