Functionalization and carbonization of cellulose nanofibrils as high-performance fiber materials and their applications

Cellulose nanofibrils;Composites;Aerogels;Bio-carbons;Electrocatalysts

Mulyadi, Arie Tri Nugroho ; Deng, Yulin Schork, Francis J. Behrens, Sven H. Grover, Martha Singh, Preet Chemical and Biomolecular Engineering ; Deng, Yulin

University:Georgia Institute of Technology

Department:Chemical and Biomolecular Engineering

关键词: Cellulose nanofibrils;    Composites;    Aerogels;    Bio-carbons;    Electrocatalysts;   

Others  :  https://smartech.gatech.edu/bitstream/1853/59135/1/MULYADI-DISSERTATION-2016.pdf

美国|英语

来源: SMARTech Repository

【 摘 要 】

Modification strategies for cellulose nanofibrils to generate hydrophobic fiber surface and carbon-based fiber were proposed. The enhanced functionality for the obtained nanofiber was utilized for diverse engineering applications, such as reinforcing filler for hydrophobic thermoplastic, oil absorbent, and carbon-based electrocatalyst. As the neat cellulose nanofibrils are amphiphilic nanoparticles with relatively high surface energy, surface hydrophobization is an important approach to lower the surface energy and induce hydrophobic-oleophilic surface characteristics. In the case of utilizing cellulose nanofibrils as filler materials, surface compatibility with hydrophobic polymers is a problem that causes an ineffective stress transfer between the filler and polymer matrix. Surface hydrophobization of cellulose nanofibrils was found necessary to improve the tensile strength of the nanocomposite, especially at higher filler loading. Furthermore, the hydrophobic cellulose nanofibrils were found useful to prepare a 3D porous material such as aerogel. The flexible, high porosity, and low density properties of the hydrophobic aerogel allowed the material to have high absorption capacity toward oil/organic solvent and to be compressible. In the case of carbon nanofibers prepared from cellulose nanofibrils precursor, functionalization methods such as heteroatoms-doping and recombination were included to enhance the electrochemical and catalytic activity of the carbon material. The results show that the obtained carbon nanofibers can compete with the graphene-based carbon material as electrocatalysts.