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Simultaneous/direct chemomechanical densification and downsizing of weak paulownia wood to produce a strong, unidirectional, all-wooden nanocomposite


Microstructure-free, strong, binderless, all-wooden nanocomposites (AWNCs) with unidirectional nanofibrils were directly fabricated from lightweight paulownia raw wood (RW) through simultaneous chemomechanical densification and downsizing processes with three main steps: (1) partial delignification, (2) partial dissolution with ionic liquid (IL) or oxidation with the free radical 2,2,6,6-tetramethylpiperidine 1-oxyl (TEMPO) and ammonium persulfate (APS) and (3) hot pressing with cyclic pressurizing-depressurizing conditions. The density of RW was 0.310 g/cm3, while the density of the AWNCs drastically increased to 1.24 g/cm3. Field emission scanning electron microscopy (FE-SEM) demonstrated that the microstructure of RW fibers was directly dismantled into wood nanofibrils during AWNC production. Two-dimensional wide angle X-ray diffraction (2D-WAXS) patterns confirmed the unidirectional structure of the AWNCs. Fourier transform infrared spectroscopy (FTIR) successfully confirmed the effect of all chemical treatments on the specimens. Thermogravimetric analysis (TGA) demonstrated that AWNC-TEMPO and AWNC-APS had the lowest thermal stability. AWNC-TEMPO had the highest flexural (246 ± 15 MPa) and tensile (265 ± 17 MPa) strengths, while RW showed the minimum corresponding values of 38 ± 7 MPa and 18 ± 2.5 MPa, respectively.

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  1. Sadatnezhad, SH, Khazaeian, A, Sandberg, D & Tabarsa, T Continuous surface densification of wood: A new concept for large-scale industrial processing. BioResources (2017).

  2. Burnard MD, Kutnar A. Wood, and human stress in the built indoor environment: a review. Wood Sci Technol. 2015;49:969–86.

    Article  CAS  Google Scholar 

  3. Qi Y, Jang JH, Hidayat W, Lee AH, Lee SH, Chae HM, et al. Carbonization of reaction wood from Paulownia tomentosa and Pinus densiflora branch woods. Wood Sci Technol. 2016;50:973–87.

    Article  CAS  Google Scholar 

  4. Song, J, Chen, C, Zhu, S, Zhu, M, Dai, J, Ray, U, et al. Processing bulk natural wood into a high-performance structural material. Nature (2018).

  5. Laine K, Segerholm K, Wålinder M, Rautkari L, Hughes M. Wood densification and thermal modification: hardness, set-recovery and micromorphology. Wood Sci Technol. 2016;50:883–94.

    Article  CAS  Google Scholar 

  6. Wang Y, Wu Y, Yang F, Yang L, Wang J, Zhou J, et al. A highly transparent compressed wood prepared by cell wall densification. Wood Sci Technol. 2022;56:669–86.

    Article  CAS  Google Scholar 

  7. Li, K, Wang, S, Chen, H, Yang, X, Berglund, LA & Zhou, Q. Self-densification of highly mesoporous wood structure into a strong and transparent film. Adv Mater (2020).

  8. Kutnar A, Kamke FA. Influence of temperature and steam environment on set recovery of compressive deformation of wood. Wood Sci Technol 2011 465. 2011;46:953–64.

    Google Scholar 

  9. Soykeabkaew, N, Arimoto, N, Nishino, T & Peijs, T All-cellulose composites by surface selective dissolution of aligned ligno-cellulosic fibres. Compos Sci Technol (2008).

  10. Nishino T, Matsuda I, Hirao K. All-cellulose composite. Macromolecules. 2004;37:7683–7.

    Article  CAS  Google Scholar 

  11. Arévalo R, Peijs T. Binderless all-cellulose fibreboard from microfibrillated lignocellulosic natural fibres. Compos Part A Appl Sci Manuf 2016;83:38–46.

    Article  Google Scholar 

  12. Duchemin BJC, Mathew AP, Oksman K. All-cellulose composites by partial dissolution in the ionic liquid 1-butyl-3-methylimidazolium chloride. Compos Part A Appl Sci Manuf 2009;40:2031–7.

    Article  Google Scholar 

  13. Orelma H, Tanaka A, Vuoriluoto M, Khakalo A, Korpela A. Manufacture of all-wood sawdust-based particle board using ionic liquid-facilitated fusion process. Wood Sci Technol 2021;55:331–49.

    Article  CAS  Google Scholar 

  14. Yousefi, H, Faezipour, M, Nishino, T, Shakeri, A & Ebrahimi, G All-cellulose composite and nanocomposite made from partially dissolved micro-and nanofibers of canola straw. Polym J (2011).

  15. Gindl W, Keckes J. All-cellulose nanocomposite. Polymer. 2005;46:10221–5.

    Article  CAS  Google Scholar 

  16. Yousefi H, Nishino T, Faezipour M, Ebrahimi G, Shakeri A, Morimune S. All-cellulose nanocomposite made from nanofibrillated cellulose. Adv Compos Lett 2010;19:190–5.

    Article  Google Scholar 

  17. Mohammadi Amirabad, L, Jonoobi, M, Mousavi, NS, Oksman, K, Kaboorani, A & Yousefi, H. Improved antifungal activity and stability of chitosan nanofibers using cellulose nanocrystal on banknote papers. Carbohydr Polym (2018).

  18. Yousefi, H, Nishino, T, Faezipour, M, Ebrahimi, G & Shakeri, A. Direct fabrication of all-cellulose nanocomposite from cellulose microfibers using ionic liquid-based nanowelding. Biomacromolecules (2011).

  19. Rindler A, Vay O, Hansmann C, Müller U. Dimensional stability of multi-layered wood-based panels: a review. Wood Sci Technol. 2017;51:969–96.

    Article  CAS  Google Scholar 

  20. Segal L, Creely JJ, Martin AE, Conrad CM. An empirical method for estimating the degree of crystallinity of native cellulose using the X-Ray Diffractometer. Text Res J 1959;29:786–94.

    Article  CAS  Google Scholar 

  21. Kaffashsaie, E, Yousefi, H, Nishino, T, Matsumoto, T, Mashkour, M, Madhoushi, M, et al. Direct conversion of raw wood to TEMPO-oxidized cellulose nanofibers. Carbohydr Polym (2021).

  22. Yan, Y, Dong, Y, Chen, H, Zhang, S & Li, J. Effect of catalysts and sodium hydroxide on glyoxal-treated wood. BioResources (2014).

  23. Nishino T, Arimoto N. All-cellulose composite prepared by selective dissolving of fiber surface. Biomacromolecules. 2007;8:2712–6.

    Article  CAS  PubMed  Google Scholar 

  24. Mashkour M, Tajvidi M, Kimura F, Yousefi H, Kimura T. Strong highly anisotropic magnetocellulose nanocomposite films made by chemical peeling and in situ welding at the interface using an ionic liquid. ACS Appl Mater Interfaces. 2014;6:8165–72.

    Article  CAS  PubMed  Google Scholar 

  25. Khakalo A, Tanaka A, Korpela A, Hauru LKJ, Orelma H. All-Wood Composite Material by Partial Fiber Surface Dissolution with an Ionic Liquid. ACS Sustain Chem Eng 2019;7:3195–202.

    Article  CAS  Google Scholar 

  26. Moosavinejad, SM, Madhoushi, M, Vakili, M & Rasouli, D. Evaluation of degradation in chemical compounds of wood in historical buildings using Ft-Ir And Ft-Raman vibrational spectroscopy. Maderas Cienc y Tecnol (2019).

  27. Shibata, M, Teramoto, N, Nakamura, T & Saitoh, Y. All-cellulose and all-wood composites by partial dissolution of cotton fabric and wood in ionic liquid. Carbohydr Polym (2013).

  28. Lin, N, Bruzzese, C & Dufresne, A. TEMPO-oxidized nanocellulose participating as crosslinking aid for alginate-based sponges. ACS Appl Mater Interfaces (2012).

  29. Isogai A. TEMPO-catalyzed oxidation of polysaccharides. Polym J. 2021;54:387–402.

    Article  Google Scholar 

  30. Pucetaite, M. Archaeological wood from the Swedish warship Vasa studied by infrared microscopy. (Lund university Press, Sweden, pp 16, 2012).

  31. Mascheroni, E, Rampazzo, R, Ortenzi, MA, Piva, G, Bonetti, S & Piergiovanni, L. Comparison of cellulose nanocrystals obtained by sulfuric acid hydrolysis and ammonium persulfate, to be used as coating on flexible food-packaging materials. Cellulose (2016).

  32. Isogai A, Saito T, Fukuzumi H. TEMPO-oxidized cellulose nanofibers. Nanoscale. 2011;3:71–85.

    Article  CAS  PubMed  Google Scholar 

  33. Filipova, I, Serra, F, Tarrés, Q, Mutjé, P & Delgado-Aguilar, M. Oxidative treatments for cellulose nanofibers production: a comparative study between TEMPO-mediated and ammonium persulfate oxidation. Cellulose (2020).

  34. Sehaqui H, Allais M, Zhou Q, Berglund LA. Wood cellulose biocomposites with fibrous structures at micro- and nanoscale. Compos Sci Technol 2011;71:382–7.

    Article  CAS  Google Scholar 

  35. Yousefi H, Faezipour M, Hedjazi S, Mousavi MM, Azusa Y, Heidari AH. Comparative study of paper and nanopaper properties prepared from bacterial cellulose nanofibers and fibers/ground cellulose nanofibers of canola straw. Ind Crops Prod. 2013;43,:732–7.

    Article  Google Scholar 

  36. Henriksson M, Berglund LA, Isaksson P, Lindström T, Nishino T. Cellulose nanopaper structures of high toughness. Biomacromolecules. 2008;9:1579–85.

    Article  CAS  PubMed  Google Scholar 

  37. Berglund LA, Peijs T. Cellulose biocomposites—from bulk moldings to nanostructured systems. MRS Bull 2010;35:201–7.

    Article  CAS  Google Scholar 

  38. Yousefi H, Azad S, Mashkour M, Khazaeian A. Cellulose nanofiber board. Carbohydr Polym 2018;187:133–9.

    Article  CAS  PubMed  Google Scholar 

  39. Robert J. Chapter 12—Mechanical properties of wood-based composite materials. Wood Handb Wood Eng Mater, 2010. p. 556–8.

  40. Yousefi H, Faezipour M, Nishino T, Shakeri A, Ebrahimi G. All-cellulose composite and nanocomposite made from partially dissolved micro-and nanofibers of canola straw. Polym J 2011;43:559–64.

    Article  CAS  Google Scholar 

  41. Ghaderi M, Mousavi M, Yousefi H, Labbafi M. All-cellulose nanocomposite film made from bagasse cellulose nanofibers for food packaging application. Carbohydr Polym 2014;104:59–65.

    Article  CAS  PubMed  Google Scholar 

  42. Yousefi H, Mashkour M, Yousefi R. Direct solvent nanowelding of cellulose fibers to make all-cellulose nanocomposite. Cellulose. 2015;22:1189–1200.

    Article  CAS  Google Scholar 

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EK would like to acknowledge the financial support of the Iranian Ministry of Sciences, Research, and Technology. The authors are also grateful for Nano Novin Polymer Co. (Iran) for its kind cooperation within the primary experiments of this study.

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Correspondence to Hossein Yousefi.

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Kaffashsaei, E., Yousefi, H., Nishino, T. et al. Simultaneous/direct chemomechanical densification and downsizing of weak paulownia wood to produce a strong, unidirectional, all-wooden nanocomposite. Polym J 55, 691–702 (2023).

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