High porosity cellulose nanopapers as reinforcement in multi-layer epoxy laminates

• Main Authors: Mautner, Andreas, Wan Nawawi, Wan Mohd Fazli, Koon-Yang, Lee, Bismarck, Alexander
• Format: Article
• Language: English; English; English
• Published: Elsevier Ltd 2020
• Subjects: TP Chemical technology; TP248.13 Biotechnology
• Online Access: http://irep.iium.edu.my/82235/1/82235_High%20porosity%20cellulose%20nanopapers.pdf; http://irep.iium.edu.my/82235/2/82235_High%20porosity%20cellulose%20nanopapers_SCOPUS.pdf; http://irep.iium.edu.my/82235/3/82235_High%20porosity%20cellulose%20nanopapers_WOS.pdf; http://irep.iium.edu.my/82235/; https://www.sciencedirect.com/science/article/abs/pii/S1359835X20300178

Utilizing high-performance cellulose nanopapers as 2D-reinforcement for polymers allows for realizing high-loading-fraction (80 vol-%), high-performance (strength > 150 MPa, modulus > 10 GPa) laminated nanopaper reinforced epoxy composites. Such cellulose nanopapers are inherently dense, which renders them difficult to be impregnated with the epoxy-resin. High-porosity nanopapers facilitate better resin impregnation, truly utilizing the properties of single cellulose nanofibres instead of the nanofibre network. We report the use of high-porosity (74%) but low strength and modulus bacterial cellulose (BC) nanopapers, prepared from BC-in-ethanol dispersion, as reinforcement for epoxy-resin. High-porosity nanopapers allowed for full impregnation of the BC-nanopapers with epoxy-resin. The resulting BC-reinforced epoxy-laminates possessed high tensile modulus (9 GPa) and strength (100 MPa) at a BC loading of 30 vol-%, resulting from very low void-fraction (3 vol-%) of these papregs compared to conventional nanopaper-laminates (10+ vol.-%). Better resin impregnation of less dense nanocellulose networks allowed for maximum utilization of stiffness/strength of cellulose nanofibrils. © 2020 Elsevier Ltd