Aerogels from Unaltered Bacterial Cellulose: Application of scCO(2) Drying for the Preparation of Shaped, Ultra-Lightweight Cellulosic Aerogels

作者：Liebner Falk^*; Haimer Emmerich; Wendland Martin; Neouze Marie Alexandra; Schlufter Kerstin; Miethe Peter; Heinze Thomas; Potthast Antje; Rosenau Thomas

来源：Macromolecular Bioscience, 2010, 10(4): 349-352.

DOI：10.1002/mabi.200900371

• aerogels
• bacterial cellulose
• biopolymers
• porosity
• renewable resources
• ultra-lightweight materials

Bacterial cellulose produced by the gram-negative bacterium Gluconacetobacter xylinum was found to be an excellent native starting material for preparing shaped ultra-lightweight cellulose aerogels. The procedure comprises thorough washing and sterilization of the aquogel, quantitative solvent exchange and subsequent drying with supercritical carbon dioxide at 40 degrees C and 100 bar. The average density of the obtained dry cellulose aerogels is only about 8 mg.cm(-3) which is comparable to the most lightweight silica aerogels and distinctly lower than all values for cellulosic aerogels obtained from plant cellulose so far. SEM, ESEM and nitrogen adsorption experiments at 77 K reveal an open-porous network structure that consists of a comparatively high percentage of large mesopores and smaller macropores.

• 出版日期2010-4-8