改性玉米秸秆材料的制备及吸油性能的研究

以粉末状玉米秸秆(Raw corn stalks,RCS)为基体,甲基丙烯酸丁酯和苯乙烯为单体,采用悬浮聚合法制备高吸油复合材料(Butylmethacrylate and styrene grafted corn stalks,BMS-CS).实验确定的最佳制备条件为:在50℃,引发剂硝酸铈铵为2.0mmol·L-1,单体甲基丙烯酸丁酯和苯乙烯浓度分别为0.6mol·L-1、0.012mol·L-1,交联剂N,N’-亚甲基双丙烯酰胺质量分数为0.1%(相对于RCS的质量)的前提下反应25h.同时,实验考察了吸附时间、吸附温度及保油时间等对材料吸油性能的影响,并通过傅里叶变换红外光谱仪、X-射线衍射和扫描电镜对改性前后样品的结构进行表征.结果表明,BMS-CS表面变得粗糙且呈毛刺状,具有较多不规则的褶皱;结晶度的下降也印证了粗糙度的增加;红外图谱中新出现的酯基和苯乙烯基的吸收峰说明亲油单体被接枝到RCS表面;两种原因共同促进了改性材料吸油性能的增加.吸油数据显示,常温下RCS和BMS-CS的吸油量分别为5.23g·g-1和20.12g·g-1,后者是前者的3.85倍,即改性后的材料吸油性能明显增加.

An experimental investigation of corn stalk grafted by physico-chemical crosslinking as sorbent materials for oil spills

Powdered raw corn stalk (RCS) was modified with butyl methacrylate and styrene by means of suspension polymerization to obtain a new crude oil absorption material,butyl methacrylate and styrene grafted corn stalks (BMS-CS).The optimum conditions determined by orthogonal experiment were as follows:concentrations of initiator ammonium ceric nitrate,monomer n-butyl methacrylate and styrene were 2.0 mmol·L^-1,0.6 mol·L^-1 and 0.012 mol·L^-1,respectively;the dosage of cross-linked agent N,N'-methylene-bis-acrylamide was 0.1% (relative to the quality of RCS);and the reaction was conducted simultaneously at 50°C for 25 h.Oil absorption capacity was investigated at different adsorption time,temperature and retention time.Physico-chemical structure of materials was characterized by Fourier transform infrared spectroscopy,X-ray diffraction and scanning electron microscopy.The results displayed that BMS-CS was corroded and became rougher with more irregular folds;an increase of roughness was also convinced by the decline in crystallinity.Newly emerged absorption peaks in FT-IR spectra indicated that hydrophobic groups had been grafted to the surface of RCS.Both of them enhanced oil absorption capacity of modified material.Performance measurement showed that oil absorption capacities of RCS and BMS-CS were 5.23 g·g^-1 and 20.12 g·g^-1 at room temperature,with the latter 3.85 times higher than the former.