Reinforced low density alginate-based aerogels: Preparation, hydrophobic modification and characterization

Homogeneous reinforced low density alginate-based aerogel was prepared by ionotropic gelation of sodium alginate. N,N′-methylenebisacrylamide and carboxy-methylcellulose were introduced into the alginate hydrogel matrix as reinforcing agents, respectively. Analysis of FTIR spectra showed that the reinforcing agents had strong interaction with alginate through hydrogen bond, which enhanced the aerogel's compression strength effectively. Meanwhile, density and volume shrinkage of the aerogels retained at an appropriate low level. Highly hydrophobic aerogels were obtained by the following targeted modification using a CCl4 plasma treatment. Together with hydrophobicity, the alginate-based aerogels can be used as potential biodegradable, lightweight and oil-absorptive materials.

► Homogeneous, low density and low shrinkage alginate-based aerogels were prepared with an easy method.
► The compressive strength of alginate-based aerogels was reinforced.
► Nature property of the alginate aerogels was converted from hydrophilicity into hydrophobicity by cold plasma technology.
► Reinforced and hydrophobic alginate aerogels showed potential as oil-absorptive materials.