Song Ying, Liu Lijian, Weng Xiaocheng, Zhuo Renxi
Department of Polymer Science, College of Chemistry and Molecular Science, Wuhan University, Wuhan 430072, P. R. China.
J Biomater Sci Polym Ed. 2003;14(3):241-53. doi: 10.1163/156856203763572699.
Acid-initiated ring-opening polymerization (ROP) of epsilon-caprolactone (epsilon-CL) was conducted under microwave irradiation (MI) at 2.45 GHz. At this frequency, metallic catalysts were no longer necessary. The effects of microwave power, irradiation time, epsilon-CL: acid molar ratio and acidity of acid on the polymerization were investigated. Both the rate of polymerization and the molar mass of polymer obtained were enhanced in comparison with conventional thermal method. Poly(epsilon-caprolactone) (PCL) with weight-average molar mass (Mw) over 12000 g/mol and Mw/Mn below 1.6 was synthesized in the presence of carboxylic acids such as maleic acid (MA), succinic acid (SA) and adipic acid (AA). The polymerization was also carried out when the monomer contained a certain amount of ibuprofen (IBU), by which, the IBU-PCL controlled release system was prepared directly. The release of IBU from the system was sustained from 12 h to 9 days with IBU content in weight increasing from 5 to 20%. It seems that this is a promising method to prepare drug controlled release systems.
在2.45 GHz微波辐射（MI）下进行了ε-己内酯（ε-CL）的酸引发开环聚合（ROP）。在此频率下，不再需要金属催化剂。研究了微波功率、辐射时间、ε-CL与酸的摩尔比以及酸的酸度对聚合反应的影响。与传统热法相比，聚合速率和所得聚合物的摩尔质量均有所提高。在马来酸（MA）、琥珀酸（SA）和己二酸（AA）等羧酸存在下，合成了重均摩尔质量（Mw）超过12000 g/mol且Mw/Mn低于1.6的聚（ε-己内酯）（PCL）。当单体含有一定量的布洛芬（IBU）时，也进行了聚合反应，由此直接制备了IBU-PCL控释系统。IBU从该系统中的释放持续12小时至9天，IBU的重量含量从5%增加到20%。看来这是一种制备药物控释系统的有前景的方法。
