How wood made transparent is replacing glass

How wood made transparent is replacing glass

Can Wood Replace Glass in Buildings?

The Concept of Transparent Wood

  • The idea is to make wood transparent, allowing it to function like glass while providing better insulation.
  • A significant amount of heat (25%) escapes through traditional glass windows, highlighting the need for improved materials.

Historical Context and Scientific Discovery

  • German botanist Siegfried Fink first bleached wood to study plants in 1992, leading to later inquiries about its potential as a glass substitute.
  • Swedish scientist Lars Berglund revisited Fink's work, questioning if this modified wood could replace conventional glass.

The Process of Creating Transparent Wood

  • By removing lignin from wood, researchers create hollow channels that can be filled with a clear polymer, resulting in a material that allows approximately 90% light transmission.
  • This process retains the structural strength of wood while preventing shattering, unlike traditional glass.

Thermal Properties and Advantages Over Glass

  • Unlike solid glass which easily conducts heat, the microscopic structure of treated wood slows down heat transfer by five times.
  • This innovative material permits visible light passage while blocking infrared radiation that carries heat away.

Conclusion on Material Innovation

  • For thousands of years, humans have melted sand to create glass; however, the solution for better building materials has been available in forests all along.
Video description

Transparent wood is a real material: a wood-derived composite that transmits up to about 90% of visible light while insulating far better than glass. It is made by delignification — chemically removing lignin, the aromatic polymer whose chromophores give wood its brown colour and absorb light — leaving a porous, near-white cellulose scaffold of empty vessels and tracheids. That scaffold is then infiltrated with a refractive-index-matched polymer (typically PMMA or epoxy, n ≈ 1.5), which suppresses light scattering at the cell-wall/air interfaces and renders the structure optically clear. The result retains cellulose's mechanical strength, so it is tough and does not shatter like glass. Its thermal advantage is largely conductive: transparent wood has a thermal conductivity around 0.2 W/m·K, roughly five times lower than soda-lime glass (~1 W/m·K), because the retained cellular architecture breaks up the direct conduction path. The high optical haze also scatters transmitted light into a room. Because windows are among the weakest points for heat loss in buildings, a transparent yet insulating structural material is an attractive, more sustainable alternative to glass. First demonstrated by botanist Siegfried Fink in 1992 to study wood anatomy, the material was revisited around 2016 by Lars Berglund's group at KTH and Liangbing Hu's group at the University of Maryland as candidate glazing. References Fink, S. (1992). Transparent Wood – A New Approach in the Functional Study of Wood Structure. Holzforschung, 46(5), 403–408. Li, Y., Fu, Q., Yu, S., Yan, M., & Berglund, L. (2016). Optically Transparent Wood from a Nanoporous Cellulosic Template. Biomacromolecules, 17(4), 1358–1364. Zhu, M., Song, J., Li, T., et al. (2016). Highly Anisotropic, Highly Transparent Wood Composites. Advanced Materials, 28(26), 5181–5187. Montanari, C., Li, Y., Chen, H., Yan, M., & Berglund, L. (2019). Transparent Wood for Thermal Energy Storage and Reversible Optical Transmittance. ACS Applied Materials & Interfaces, 11(22), 20465–20472. PHENOMICA — precise, contemplative science, one phenomenon at a time. #materialscience #transparentwood #cellulose #engineering