Research Institute of Resources Insects, Chinese Academy of Forestry, Kunming 650224, People's Republic of China.
Faculty of Chemical Engineering, Kunming University of Science and Technology, Kunming 650550, People's Republic of China.
J Agric Food Chem. 2020 Mar 25;68(12):3779-3785. doi: 10.1021/acs.jafc.9b07629. Epub 2020 Mar 12.
Renewable biobased porous aerogels with excellent biodegradability have versatile applications in oil/water separation, catalysis, and tissue engineering. However, processing of the porous matrix is challenging due to the high energy consumption and low efficiency from the fabrication procedures, such as freeze-drying or critical-drying of the hydrogel, which need to be improved. In the present study, natural amphiphilic oligomer shellac secreted by the lac insect was employed to fabricate the porous template, which could self-assemble into a continuous rigid network with a hydrophobic core. Because of the hydrophobic core, the hydrated shellac network could be directly dried without collapse by the ambient air. The air-drying shellac aerogel presented a great mechanical property. The silane-coating treatment converted this shellac aerogel into a hydrophobic material that absorbed various organic solvents and oils. Also, this silane-coated shellac aerogel also could remove organic solvent or oil from the bottom or surface of the water. Notably, the saturable aerogel rapidly degraded in pH 14 and released the solvent absorbed by this matrix. This porous and hydrophobic matrix also could be applied as a filter that could connect with a vacuum pump to assemble a device for continuous collecting of oil from water. It also has great potential to be employed as a high-efficiency strategy to treat large scale oil spill issues. A new porous template composed of natural resin secreted by the insect was fabricated, and the whole fabrication process was green, low-cost, and energy saving. The surface of this template could be modified further to effectuate other processes, such as catalysis, heavy metal absorption, and tissue proliferation.
可再生的生物基多孔气凝胶具有优异的生物降解性，在油水分离、催化和组织工程等领域有广泛的应用。然而，由于多孔基质的加工具有挑战性，例如水凝胶的冷冻干燥或临界干燥，需要改进这些工艺，这些工艺的能量消耗高，效率低。在本研究中，采用由紫胶虫分泌的天然两亲性低聚物紫胶来制备多孔模板，它可以自组装成具有疏水核的连续刚性网络。由于疏水核的存在，水合紫胶网络可以在空气中直接干燥而不会塌陷。空气干燥的紫胶气凝胶具有很好的机械性能。硅烷涂层处理将这种紫胶气凝胶转化为一种疏水材料，可以吸收各种有机溶剂和油。此外，这种硅烷涂层的紫胶气凝胶还可以从水的底部或表面去除有机溶剂或油。值得注意的是，可饱和的气凝胶在 pH 值为 14 时迅速降解，并释放出被这种基质吸收的溶剂。这种多孔疏水的基质也可以用作过滤器，可以与真空泵连接，组装一个从水中连续收集油的装置。它也有很大的潜力被用作处理大规模溢油问题的高效策略。制备了一种由昆虫分泌的天然树脂组成的新型多孔模板，整个制备过程绿色、低成本、节能。该模板的表面可以进一步修饰，以实现其他过程，如催化、重金属吸收和组织增殖。
