Owing to the increasing energy demands and the environmental constraints, the need for bio-based materials has been on the rise due to their variety of favorable properties like biocompatibility, cost-effectiveness, large specific surface area, high porosity, and non-toxicity. Thermal stability and mechanical strength of aerogels are highly dependent on their micro-porous structures. A three-dimensional structure based on cellulose nanofiber/chitosan ( CNF/CS) aerogels was built using two different freezing methodologies, namely random freezing, and unidirectional freezing techniques, by changing mold shapes. The unidirectional aerogels ultimately resulted in high-temperature stability and mechanical strength. The results show that the unidirectional CNF/CS( u-CNF/CS) aerogels contain controlled micro porous orientation relative to random-CNF/CS ( r-CNF/CS) aerogels with the disordered porous distribution. The high-temperature stability with an increase of glass transition temperature Tg from 275 ℃( CNF ) to 283 ℃ ( CNF/CS ) , the ultra-low thermal conductivity of 0. 030 W/( m · K ) , and mechanical robustness of u-CNF/CS aerogels make them quite favorable for practical applications.

College of Textiles,Donghua University,Shanghai 201620,China;Key Laboratory of Textile Science&Technology,Ministry of Education,Donghua University,Shanghai 201620,China;Department of Chemistry,Zhejiang University,Hangzhou 310027,China

[1]CHAUDARY Aneeba;CHUDHARY Tayba;FAROOQ Amjad;ZHANG Meiling;PATOARY Mohammed Kayes;LIU Lifang-.Polysaccharides Based Random and Unidirectional Aerogels for Thermal and Mechanical Stability)[J].东华大学学报（英文版）,2022(02):103-109

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