ST-g-NMA-AM的制备及其吸附性能

以红薯淀粉(ST)为原料,丙烯酰胺(AM)为单体,N-羟甲基丙烯酰胺(NMA)为单体和交联剂,采用反向乳液聚合法制备了NMA-AM接枝ST(ST-g-NMA-AM)。考察了NMA用量、引发剂过硫酸铵用量及反应温度对接枝率的影响,利用傅里叶变换红外光谱对其结构进行表征。以亚甲基蓝为吸附质,考察了ST-g-NMA-AM对亚甲基蓝的吸附性能。结果表明:当NMA用量为0.75 g,引发剂用量为0.0500 g,反应温度为55℃时,单体转化率和接枝率最高,分别为90.41%,45.38%;当亚甲基蓝质量浓度为20 mg/L,吸附剂ST-g-NMA-AM质量浓度为1 g/L时,吸附量随着NMA用量的增加而先增大后减小,当引发剂用量为0.0500 g,NMA用量为0.75 g时,吸附量最大,为16.140 mg/g。

Preparation and adsorption of ST-g-NMA-AM

Sweet potato starch(ST)was selected as the raw material,acrylamide as the monomer(AM),N-methylolacrylamide(NMA)as the monomer and crossslinking agent to prepare ST grafted NMA-AM(ST-g-NMA-AM)via reverse emulsion polymerization,whose structure was characterized by Fourier transform infrared spectroscope.The effects of the amount of NMA,the amount of the initiator of ammonium persulfate and the reaction temperature on grafting ratio were observed.The adsorption property of the grafted copolymer was tested with methylene blue as the adsorbate.The results show that the monomer conversion and grafting ratio of the copolymer reach the highest of 90.41%and 45.38%respectively when the amount of NMA and persulfate are 0.75 g and 0.05 g at 55℃.The adsorption quantity rises and then falls with the increase of NMA when the mass concentration of methylene blue and ST-g-NMA-AM are 20 mg/L and 1 g/L.The adsorption quantity reaches the highest of 16.140 mg/g when the amount of initiator and NMA are 0.0500 g and 0.75 g respectively.