含甲基丙烯酸二甲氨基乙酯的丝瓜络的合成及吸附性能

Synthesis and adsorption of loofah containing polymethacylic acid two methylamino ethyl ester brushes

摘要:

以表面含溴的丝瓜络为大分子引发剂（loofah-Br），溴化铜（CuBr2）/五甲基二乙烯基三胺（PMDETA）/抗坏血酸（Vc）为催化体系，通过电子转移活化再生催化原子转移自由基聚合（ARGET ATRP）方法，制备了含聚甲基丙烯酸二甲氨基乙酯刷的丝瓜络接枝共聚物loofah-g-PDMAEMA；采用傅里叶红外光谱（FT-IR）及热重分析(TGA)对其结构和性能进行表征；考察了影响Pb2+吸附的主要因素，研究了对Pb2+的重复吸附性能。结果表明，loofah-g-PDMAEMA对Pb2+具有良好的吸附性；吸附最佳条件为：温度30℃、pH=5.5、吸附时间5h时；最大吸附量可达107.8mg/g；吸附过程符合准二级动力学模型；经过5次重复使用后，吸附量可达首次吸附量的84.73% 。

Abstract:

Loofah graft copolymers (loofah-g-PDMAEMA) was synthesized via electron transfer for atom transfer radical polynerization(ARGET ATRP), using loofah with bromide side-group(loofah-Br) as the macroinitiator and N,N,N′,N′,N″-pentamethyldiethylenetriamine (PMDETA)/copper(Ⅱ) bromide(CuBr2) as catalytic system, vitamin C as reducing agent. Chemical structure, crystalline structure and thermal stability of modified loofah were characterized by fourier transform infrared spectroscopy(FT-IR), thermogravimetric analysis(TGA). The lead adsorption and repeated adsorption performance of the loofah-g-PDMAEMA were studied. The results indicated that loofah-g-PDMAEMA possesses good adsorption capacity of Pb2+. loofah-g-PDMAEMA achieved the maximum adsorption capacity of 107.8mg/g under the best adsorption conditions when the temperature was 30°C, the pH was 5.5, and adsorption time was 5h. The adsorption process was conformed well to the pseudo-second-order kinetic model. Besides, after 5 reuses, the adsorption capacity can reach 84.73% of the first adsorption.