Department of Chemistry, Wuhan University , Wuhan 430072, China.
ACS Appl Mater Interfaces. 2014 Nov 26;6(22):19933-42. doi: 10.1021/am505414y. Epub 2014 Nov 7.
A highly hydrophobic and oleophilic chitin sponge was synthesized, for the first time, via a freeze-dried method and then by using a thermal chemical vapor deposition of methyltrichlorosilane (MTCS) at different relative humidity. Fourier-transform infrared, energy-dispersive X-ray spectra, and scanning electron microscopy confirmed that the silanization occurred on the pore wall surface of the chitin sponge. The MTCS-coated chitin sponge had interconnected open-cell structures with the average pore size from 20 to 50 μm, and the MTCS nanofilaments immobilized on the chitin matrix, leading to the high hydrophobicity, as a result of the existence of a solid/air composite rough surface. Cyclic compression test indicated that the hydrophobic chitin sponges exhibited excellent elasticity and high mechanical durability. The sponges could efficiently collect organics both on the surface and bottom from the water with the highest 58 times of their own weight absorption capacities through the combination of the particular wettability and great porosity. Furthermore, the biodegradation kinetics of the chitin sponge forecasted that the chitin could be completely biodegraded within 32 days by the microorganisms in the soil. This work provided a new pathway to prepare the chitin-based materials for highly effective removal of oil from water, showing potential application in the pollutant remediation field.
一种高疏水性和疏油性甲壳素海绵，首次通过冷冻干燥法合成，然后通过在不同相对湿度下使用甲基三氯硅烷（MTCS）的热化学气相沉积进行合成。傅里叶变换红外光谱、能谱和扫描电子显微镜证实了硅烷化反应发生在甲壳素海绵的孔壁表面上。MTCS 涂层甲壳素海绵具有相互连接的开孔结构，平均孔径为 20-50μm，MTCS 纳米纤维固定在甲壳素基质上，导致其具有高疏水性，这是由于存在固/气复合粗糙表面。循环压缩试验表明，疏水甲壳素海绵表现出优异的弹性和高机械耐久性。这些海绵通过特殊的润湿性和大孔隙率的结合，可以有效地从水中收集表面和底部的有机物，最高可吸收自身重量的 58 倍。此外，甲壳素海绵的生物降解动力学预测，壳聚糖在土壤中的微生物作用下，可在 32 天内完全降解。这项工作为制备基于甲壳素的材料以有效去除水中的油提供了新途径，有望在污染物修复领域得到应用。
