羧甲基纤维素钠修饰的聚氨酯泡沫制备磁性吸油材料

Preparation and Oil Absorption of Magnetic and Porous Materials Based on Carboxymethyl Cellulose Sodium Modified Polyurethane Foams

采用聚氨酯泡沫为模板,依次修饰羧甲基纤维素钠(CMC)、Fe^(3+),在惰性气氛中高温热处理反应,制备多孔结构的磁性吸油材料.用光学显微镜、扫描电子显微镜、红外吸收光谱、X-射线衍射、接触角等技术对材料进行表征.详细考察了加热反应温度、CMC浓度和Fe^(3+)浓度对材料吸油性能和磁性的影响规律.实验表明,当加热反应温度选择230°C,CMC浓度为0.3 wt%,FeCl_3浓度为0.1 mol/L时,材料吸油性能最佳,对正己烷、二甲苯、环己烷、甲苯、乙酸乙酯、氯仿、机油、原油等有机溶剂和油类分子的吸附容量为10倍左右.磁性多孔材料具有明显的亲油、疏水特性,水的接触角达115.9°,同时材料密度只有0.036g/cm^3,能够漂浮于水面,实现对水面有机溶剂的快速吸附.吸附后的材料在外界磁场控制下,能够通过磁分离方式从水面快速分离.该材料具有良好的循环利用性能,可重复使用20次以上,吸油性能仍然保持良好.

Magnetic and porous materials with effectively oil-absorbing and magnetic responsive properties were prepared through a facile way from carboxymethyl cellulose sodium（CMC） modified polyurethane foam. Polyurethane foam was first washed and immersed into CMC aqueous solution to modify the polyurethane foam by CMCs. The modified foam was then dipped into aqueous Fe Cl3 solution for further modification by Fe3＋through the interaction between Fe^3＋ and the carboxy groups of CMC. The composite porous materials were put into a teflon autoclave and the temperature was elevated to 230 ℃ and heated for 4 h to obtain magnetically porous materials. The as-prepared materials were characterized by optical microscope（OM）, scanning electron microscope（SEM）, Fourier transform infrared spectroscopy（FTIR）, X-ray diffraction（XRD） and contact angles. The results from OM and SEM showed that the materials were indeed porous. FTIR indicated that CMC and Fe3＋were present on the polyurethane foam sequentially. XRD pattern showed that Fe3＋ changed to Fe3O4 during the heating process. The effects of heating temperature and concentrations of CMC, Fe Cl3 solution on oil-absorbing and magnetic responsive performance of the magnetic materials were investigated in details. The materials were hydrophobic and the contact angle of water droplet on the foam surface was determined to be 115.9°. The magnetic and porous foam was oleophilic and absorbed about 10 times of its own weight for crude oil and engine oil. It absorbed also a series of solvents, including hexane, xylene, cyclohexane, toluene, ethyl acetate and chloroform. The absorption rate was in general very fast and could be used for treating oil spills. The density of the porous material was low（0.036 g/cm3）, so that they were floating on the surface of water, good for absorbing spilled oils. The as-prepared samples were magnetic, and the oil saturated samples could be easily separated by using an exterior magnet. What was more important was that the porous materials were reusable more 20 times without obvious decrease in their oil-absorption capacity.