Strong high-density composites from wheat straw

Research output: Contribution to journalArticleResearchpeer-review

Authors

  • Felix Neudecker
  • Stefan Veigel
  • Jiri Duchoslav
  • David Stifter
  • Wolfgang Gindl-Altmutter

External Organisational units

  • BOKU
  • Institute of Applied Physics
  • Wood K Plus – Competence Centre for Wood Composites and Wood Chemistry

Abstract

Wheat straw represents a promising resource for structural materials due to its inherent strength and availability as an underutilized agricultural by-product. However, structural features such as small diameters and a hollow, low-density design, as well as a hydrophobic, waxy surface layer, hinder conventional processing. We present an approach to overcome these hindrances by engineering delignified and densified straw strands into a mechanically strong unidirectional composite material. Wheat straw split into strands along the fiber direction was subjected to water-based and mild alkaline pre-treatments and subsequently densified. As a result, the average tensile strength and modulus of elasticity of straw strands improved to impressive 466 MPa and 26 GPa, respectively. Simultaneously, chemical changes to the surface enabled better adhesive bonding. The resulting unidirectional straw composites exhibited a flexural strength of 190 MPa and an elastic modulus of 20 GPa, well within the range of established wood and bamboo-based materials.

Details

Original languageEnglish
Article number108533
Number of pages11
JournalComposites Part A: Applied Science and Manufacturing
Volume188.2025
Issue numberJanuary
DOIs
Publication statusPublished - 18 Oct 2024