Polyacrylamide resin was synthesized via surface-initiated atom transfer radical polymerization ( SI-ATRP) method. Acrylic amide ( AM) was grafted onto the surface of the chloromethyl polystyrene resin via SI-ATRP in the CuBr/2, 2'-bipyridine ( Bpy) system as catalyst at room temperature. The compositions of polyacrylamide resin were determined by means of elementary analysis, FT-IR analysis and scanning electron microscopy ( SEM) . The adsorption properties, the parameters of kinetics and the thermodynamics of the resin were evaluated in details, respectively. As the results, adsorption capacity of 2,4-dichlorophenoxyacetic acid (2,4-D) increased with the initial concentrations of solution increasing at room temperature, and its highest adsorption capacity was 111. 0 mg/g with solution concentration of 8 mmol/L. Adsorption isotherm at room temperature was determined and modeled with Langmuir and Freundlich equations. The thermodynamic equilibrium functions were calculated to be ΔG<0,ΔH=268. 2 kJ/mol, ΔS>0, hence, the adsorption was spontaneous, endothermic and entropy increasing. The kinetics fitted the pseudo-second-order well. The polyacrylamide-chloromethyl polystyrene (PAM-CMCPS) resin was used for the adsorption of 2,4-D in orange sample, and good results were obtained.%以氯甲基化交联聚苯乙烯树脂( CMCPS)为载体和大分子引发剂,溴化亚铜/2,2＇-联吡啶为催化剂体系,采用了表面引发原子转移自由基聚合技术(SI-ATRP),将丙烯酰胺接枝到CMCPS树脂表面,制得了新型聚丙烯酰胺树脂( PAM-CMCPS),并且用元素分析、扫描电镜和红外光谱对其进行了表征。考察了此树脂对2,4-二氯苯氧乙酸的吸附性能、动力学和热力学参数。结果表明,此树脂对2,4-二氯苯氧乙酸的吸附量随溶液初始浓度和温度的升高而增加,当初始浓度为8 mmol/L时吸附效果最佳,树脂的静态饱和吸附容量为111.0 mg/g, Langmuir和 Freundlich 方程都呈现良好的拟合度。热力学平衡方程计算得ΔG<0,ΔH=268.2 kJ/mol,ΔS>0,表明此吸附过程是一个自发、吸热、熵增加的过程。动力学研究表明,准二级动力学方程能较好拟合动力学实验结果,该过程符合准二级动力学模型。此 PAM-CMCPS树脂应用于柑橘样品中2,4-二氯苯氧乙酸的吸附,取得了较满意的结果。
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