In the present work, wood nanocomposites were successfully prepared by lignocellulosic removal through bleaching treatment and rapidly filled the microstructure gaps with the epoxy resin. The wood composite displays a remarkable improvement in its mechanical strength and optical haze compared to native balsa wood, potentially useful for building applications and solar panels. The work utilizes a delignification process that creates promising nanoporosity in the wood cell walls resulting in chemically modified cellulose nanofibers. The method includes removal of light-absorbing Lignin - responsible for the brownish color of wood and holding cellulose and hemicellulose together. The impregnation with index matching epoxy resin was carried out and found liable for the improved strength of the wood composite. Optically transparent wood exhibited a transmittance of 70.4% and an optical haze of 68.3%, a unique property that makes it suitable for use in solar cells, as it catches more solar radiation due to the favorable angle of contact. This convenient angle of contact enhances the kinetic energy of electrons, forming a continuous path for the flow of electrons across the band gaps in silicon chips. The surface morphology and wood chemistry were examined by experimental characterization techniques including FT-IR, SEM, and Transmittance-Haze. It was observed that the bleaching process of wood decreases its lignin content and the wood color changes from dark brown to entirely white indicating no lignin content, confirmed by FTIR results. The epoxy-based matrix played a significant role in enhancing the micromechanical strength and optical properties of the synthesized wood nanocomposite. Thus, this work emphasizes more on understanding the influence of nanoscale tailoring on wood mesoporous nanostructures. As a whole, the suggestive study reveals the promising application in the prospective area of building materials.
Transparent Wood Composite, Lignin, Delignification, Micromechanical Strength, Eco-friendly, Transmittance and Haze
[1]
a) Y. Li, Q. Fu, S. Yu, M. Yan, L. Berglund, Biomacromolecules 2016, 17, 1358-1364; b) M. Zhu, J. Song, T. Li, A. Gong, Y. Wang, J. Dai, Y. Yao, W. Luo, D. Henderson, L. Hu, Advanced Materials 2016, 28, 5181-5187.
[2]
Vay O, De Borst K, Hansmann C, et al (2015) Thermal conductivity of wood at angles to the principal anatomical directions. Wood Sci Technol 49: 577–589. https://doi.org/10.1007/s00226-015-0716-x
[3]
Cabane E, Keplinger T, Künniger T, et al (2016) Functional lignocellulosic materials prepared by ATRP from a wood scaffold. Sci Rep 6: 1–10. https://doi.org/10.1038/srep31287
[4]
Zhu, M. et al (2016) Highly Anisotropic, Highly Transparent Wood Composites. Advanced materials, n/a-n/a, doi: 10.1002/adma.201600427.
[5]
Zhu H, Fang Z, Wang Z, et al (2016) Extreme light management in mesoporous wood cellulose paper for optoelectronics. ACS Nano 10: 1369–1377. https://doi.org/10.1021/acsnano.5b06781
[6]
Eichhorn SJ, Baillie CA, Zafeiropoulos N, et al (2001) Current international research into cellulosic fibres and composites. J Mater Sci 36: 2107–2131. https://doi.org/10.1023/A:1017512029696
[7]
E. Sjöström, Wood Chemistry: Fundamentals and Applications, Gulf Professional Publishing, 1993.
[8]
A. B. Scranton, A. B. Kinney, i (1984) 1518–1520.
[9]
Müller U, Rätzsch M, Schwanninger M, et al (2003) Yellowing and IR-changes of spruce wood as result of UV-irradiation. J Photochem Photobiol B Biol 69: 97–105. https://doi.org/10.1016/S1011-1344(02)00412-8
[10]
Wang S, Lu A, Zhang L (2016) Recent advances in regenerated cellulose materials. Prog Polym Sci 53: 169–206. https://doi.org/10.1016/j.progpolymsci.2015.07.003
[11]
Fang Z, Zhu H, Bao W, et al (2014) Highly transparent paper with tunable haze for green electronics. Energy Environ Sci 7: 3313–3319. https://doi.org/10.1039/c4ee02236j
[12]
Li YF, Liu YX, Wang XM, Wu QL, Yu HP, Li J. Wood–polymer composites prepared by the in situ polymerization of monomers within the wood. J Appl Polym Sci 2010; 119 (6): 3207–16. https://doi,^#rg/10.1002/app.32837.
[13]
Ding WD, Koubaaa A, Chaala A (2012) Dimensional stability of methyl methacrylate hardened hybrid poplar wood. BioResources 7: 504–520. https://doi.org/10.15376/biores.7.1.0504-0520
[14]
Jiang S, Gui Z, Bao C, Dai K, Wang X, Zhou K, et al. Preparation of functionalized graphene by simultaneous reduction and surface modification and its polymethylmethacrylate composites through latex technology and melt blending. Chem Eng J2013; 226: 326–35. https://doi.org/10.1016/j.cej.2013.04.068.
[15]
Yaddanapudi HS, Hickerson N, Saini S, Tiwari A. Fabrication and characterization of transparent wood for next-generation smart building applications. Vacuum 2017; 146: 649–54. https://doi.org/10.1016/j.vacuum.2017.01.016.
