Tripathi Anurodh, Parsons Gregory N, Rojas Orlando J, Khan Saad A
Department of Chemical & Biomolecular Engineering, NC State University, 911 Partners Way, Engineering Building I (EB1), Raleigh, North Carolina 27695-7905, United States.
Department of Forest Biomaterials, NC State University, 2820 Faucette Drive, Biltmore Hall, Raleigh, North Carolina 27695-8005, United States.
ACS Omega. 2017 Aug 8;2(8):4297-4305. doi: 10.1021/acsomega.7b00571. eCollection 2017 Aug 31.
A unique combination of well-established synthesis procedures involving chemical cross-linking, careful solvent exchange to water, and subsequent freeze drying is used to produce ultralight (4.3 mg/mL) and highly porous (99.7%) cellulose diacetate (CDA) aerogels with honeycomb morphology. This versatile synthesis approach is extended to other nonaqueous polymers with hydroxyl functionalities such as cellulose acetate propionate and cellulose acetate butyrate to produce a single component polymer aerogel. These aerogels demonstrate a maximum water and oil uptake of up to 92 and 112 g/g, respectively. The honeycomb morphology provides a maximum compression strain of 92% without failure and reaches a compressive stress of 350 kPa, for 4 w/v % CDA aerogels (4%), which is higher than that reported for cellulosic aerogels. The 4% CDA aerogel were rendered hydrophobic and oleophilic via chemical vapor deposition with organosilane. The modified CDA aerogel surpasses their counterparts in maintaining their mechanical integrity for fast oil cleanup and efficient oil retention from aqueous media under marine conditions. These aerogels are identified to be reusable and durable for a long period.
采用成熟的合成程序的独特组合,包括化学交联、小心地将溶剂交换为水以及随后的冷冻干燥,来制备具有蜂窝形态的超轻(4.3毫克/毫升)且高度多孔(99.7%)的二醋酸纤维素(CDA)气凝胶。这种通用的合成方法扩展到了其他具有羟基官能团的非水聚合物,如醋酸丙酸纤维素和醋酸丁酸纤维素,以制备单组分聚合物气凝胶。这些气凝胶的最大吸水量和吸油量分别高达92克/克和112克/克。对于4重量/体积%的CDA气凝胶(4%),蜂窝形态提供了高达92%的最大压缩应变且不会失效,抗压应力达到350千帕,这高于纤维素气凝胶的报道值。通过用有机硅烷进行化学气相沉积,使4%的CDA气凝胶具有疏水性和亲油性。在海洋条件下,改性后的CDA气凝胶在从水介质中快速清理油污和有效保留油污方面,在保持其机械完整性方面优于同类产品。这些气凝胶被确定可长期重复使用且耐用。