Bio-based cellulose aerogels with liquid absorption and retention capability for sustainable personal hygiene...

Efficient water-absorbing and water-holding materials have shown notable promise in various applications, including hygiene products, agriculture, and drug delivery systems. Opposed to traditional absorbents prepared using synthetic polymers, bio-based, environmentally friendly efficient absorbents have attracted more attention from both academia and the industry. Herein, the aerogel absorbents from functional sodium carboxymethyl cellulose (CMCNa), citric acid (CA) crosslinker, and cellulose nanofibers (CNF) have been developed via freeze-drying and cross-linking process. The effects of aerogel microstructure, doses of CMC-Na and CNF, thermal cross-linking time, salts present in solutions, and solution pH on water storage by aerogels are examined in detail. The water absorption and water retention capacities of aerogels are observed to be 153 ± 3 and 123 ± 4 g g^-1, respectively, showing satisfactory performance. The aerogels possess environmentally friendly raw materials, simple preparation method, remarkable water absorption and retention performance, demonstrating the potential to replace petroleum-based absorbents.