Surface hardness and flammability of Na2SiO3 and nano-TiO2 reinforced wood compositesShow others and affiliations
2019 (English)In: RSC Advances, E-ISSN 2046-2069, Vol. 9, no 48, p. 27973-27986Article in journal (Refereed) Published
Abstract [en]
The objective of this study was to explore an effect of the combined inorganic materials on the wood hardness and flame-retardancy properties in a concept of sustainable material management. Herein, the reinforcement of Scots pine (Pinus sylvestris L.) sapwood with sodium silicate and TiO2 nanoparticles via vacuum-pressure technique is reported. Pyrolysis of modified wood was studied by TG-FTIR analysis; the results showed that maximum weight loss for the modified wood was obtained at 40–50 °C lower temperatures compared to the reference untreated wood. The Gram–Schmidt profiles and spectra extracted at maxima absorption from Gram–Schmidt plots indicated chemical changes in wood–inorganic composites. SEM/EDS analysis revealed the presence of Na–O–Si solid gel within the wood-cell lumen and showed that TiO2 was homogeneously distributed within the amorphous Na–O–Si glass-forming phase to form a thin surface coating. EDS mapping further revealed the higher diffusivity of sodium into the cell wall compared to the silicon compound. The presence of amorphous sodium silicate and nano-TiO2 was additionally confirmed by XRD analysis. FTIR spectra confirmed the chemical changes in Scots pine sapwood induced by alkalization. Brinell hardness test showed that the hardness of the modified wood increased with the highest value (44% increase in hardness) obtained for 10% Na2SiO3–nTiO2 modified wood. The results showed good correlation between TG and flammability test; limiting oxygen index (LOI) values for the wood–inorganic composites increased by 9–14% compared to the untreated wood.
Place, publisher, year, edition, pages
Royal Society of Chemistry, 2019. Vol. 9, no 48, p. 27973-27986
National Category
Wood Science Other Mechanical Engineering
Research subject
Wood Science and Engineering
Identifiers
URN: urn:nbn:se:ltu:diva-76014DOI: 10.1039/c9ra05200cISI: 000486203200028PubMedID: 35530478Scopus ID: 2-s2.0-85072338998OAI: oai:DiVA.org:ltu-76014DiVA, id: diva2:1351551
Funder
Swedish Research Council Formas, 2018-01198
Note
Validerad;2019;Nivå 2;2019-09-18 (johcin);
For correction, see: Garskaite, E., Karlsson, O., Stankeviciute, Z. et al. Correction: Surface hardness and flammability of Na2SiO3 and nano-TiO2 reinforced wood composites. RSC Advances 9, 34086-34087 (2019). https://doi.org/10.1039/C9RA90075F
2019-09-162019-09-162022-11-02Bibliographically approved