端氨基超支化物改性纤维素的制备和吸附性能研究

Preparation of amino-terminated hyperbranched polymer grafted cellulose and its adsorption performance to dye

以丙烯酸乙酯、二乙烯三胺为原料合成端氨基超支化物。利用环氧基开环反应在纤维素/离子液体溶液中均相制备了端氨基超支化物改性纤维素吸附剂(HBPN-C),利用红外光谱仪、X射线衍射分析、扫描电镜等对HBPN-C进行表征与分析,结果表明,端氨基超支化物被成功接枝到纤维素上;HBPN-C晶型由纤维素Ⅰ变为Ⅱ型,无定形区增大,结构变得疏松多孔。吸附实验表明,吸附剂在pH=3时对阴离子染料C.I.Acid Blue 40吸附容量最大。吸附过程符合Langmuir等温线和拟二阶动力学,静电作用是主要的作用力。用0.01 mol/L的氢氧化钠溶液可完成吸附剂的脱附过程。

Amino-terminated hyperbranched polymer(HBP-NH2)are synthesized from ethyl acrylate and diethylenetriamine.Furthermore,HBP-NH2 modified cellulose adsorbent(HBPN-C)is prepared homogeneously via epoxy ring-opening reaction in a cellulose/ionic liquid solution.HBPN-C is characterized by infrared spectrometer,X-ray diffraction analysis and scanning electron microscope.It turns out that HBP-NH2 has been successfully grafted onto cellulose.The crystal form of HBPN-C changes from cellulose I to celluloseⅡ,with a larger amorphous region and a loose porous structure.Adsorption experiments show that HBPN-C adsorbent exhibits the maximum adsorption capacity to anionic dye C.I.Acid Blue 40 when pH=3.The adsorption process accords with Langmuir isotherm and pseudo-secondorder kinetics,and electrostatic action is the main force.The desorption process can be carried out with 0.01 mol·L-1 sodium hydroxide solution.