交联壳聚糖微球对喹乙醇吸附性能的研究

以壳聚糖为原料,乙酸乙酯为致孔剂,环氧氯丙烷为交联剂,通过交联法制备出改性壳聚糖,考察了交联壳聚糖微球对喹乙醇吸附的影响。结果表明,V(壳聚糖)∶V(乙酸乙酯)∶V(环氧氯丙烷)=30∶1∶1时,制备的交联壳聚糖微球对喹乙醇吸附性能较好;红外光谱表明,环氧氯丙烷与壳聚糖发生反应;扫描电镜分析验证环氧氯丙烷用量对交联壳聚糖微球吸附性能有一定影响;吸附动力学曲线得知交联壳聚糖微球在3 h对喹乙醇吸附达到平衡,有较好的吸附速度;与类似物(喹烯酮和乙酰甲喹)吸附特性比较得知,交联壳聚糖微球对喹乙醇有较好的选择吸附性。     

Synthesis of polymeric salen complexes and application in the enantioselective hydrolytic kinetic resolution of epoxides as catalysts

The polymeric (salen) Co(III) catalysts containing various counter anions have been synthesized, and the asymmetric catalytic activities of these newly synthesized polymer-type salen complexes were investigated in the HKR of terminal epoxides. The polymeric chiral salen Co(III) complexes catalyze the hydrolysis of epichlorohydrine, 1,2-epoxybutane, 1,2-epoxyhexane and epoxystyrene with very high enantioselectivities under mild conditions. The catalysts could be recovered and reused several times without further treatment after reaction, showing no loss of activity and enantioselectivity.     

Interpenetrated Polymeric Networks Based on Gellan and Poly(Vinyl Alcohol)

Abstract

The paper deals with the hydrogels of interpenetrated networks obtained by reticulation of a mixture of gellan and poly(vinyl alcohol) with epichlorohydrine in basic medium and their characterization with respect to the swelling capacity in water. The influence of some factors on the reticulation density (estimated indirectly from the swelling characteristics) is followed, namely: the macromolecular components ratio in the mixture, the polymer/reticulation agent ratio, duration, and temperature. By the proper choice of these parameter values, the hydrogels of preset swelling characteristics can be obtained. Preliminary tests proved the possibility of using these materials as carriers for drugs in view of their controlled release.