Research in porous structure of cellulose aerogel made from cellulose nanofibrils

In this study, a simple strategy to fabricate the cellulose aerogel with homogeneous porous structure and good compression strength properties has been demonstrated. The cellulose aerogel was simply prepared by adding styrene acrylic emulsion (SAE) to the TEMPO-oxidized cellulose nanofibrils (CNF), followed by freeze-drying and oven-heating, in which covalent bond between CNF and SAE was confirmed by FT-IR. Meanwhile, the regulation process of porous structure of cellulose aerogels was investigated by varying the properties of CNF, and the addition of carboxymethyl cellulose (CMC) and SAE. The results demonstrated that the porous structure of cellulose aerogel was gradually improved with increasing carboxyl content of CNF. CMC could effectively increase in specific surface area of cellulose aerogel, achieving a more preferred porous structure due to the elimination of hornification. SAE could highly enhance the uniformity of structure with specific surface area up to 184 m²/g, porosity up to 99%, and successfully improve the strength properties, showing the fabricated cellulose aerogel as a potential cushion packaging material.