Surface physicochemical properties of surface-compressed wood subjected to superheated steam treatment under varying pressures

• Published in: Construction & building materials 2024-03, Vol.418, p.135444, Article 135444
• Main Authors: Xiang, Elin, Jin, Xiaobei, Li, Jing, Huang, Rongfeng
• Format: Article
• Language: English
• Subjects: Dimensional stability; Mechanism; Poplar wood; Superheated steam pressure; Surface compression; Surface physicochemical properties
• ISSN: 0950-0618; 1879-0526
• DOI: 10.1016/j.conbuildmat.2024.135444

This study aimed to evaluate the effects of superheated steam treatment at different pressures (0.1 MPa, 0.3 MPa, 0.5 MPa, and 0.7 MPa) on the physicochemical properties of surface-compressed (SC) poplar wood. Applying a 20% compression ratio significantly increased the average density of the SC wood, while reducing its surface wettability and roughness. The compressive deformation of SC wood with superheated steam treatment (SHTSC wood) could be permanently fixed under a steam pressure of 0.7 MPa, yielding higher hydrophobic surface properties. Furthermore, the surface color of SHTSC wood resembled that of hardwood commonly used in furniture. The structural changes, such as increased surface density and decreased roughness, had a greater impact on reducing the surface wettability of SC wood than chemical changes. Additionally, superheated steam treatment led to deacetylation of hemicellulose, demethoxylation of lignin, and an increase in the relative crystallinity and crystal width of cellulose, thereby improving the surface properties and dimension stability of SHTSC wood. Overall, this study demonstrated that the combined modification treatment provides a new perspective for enhancing the utilization of fast-growing wood. •The combination of surface compression and superheated steam treatment was conducted for upgrading fast-growing wood.•High superheated steam pressure was able to permanently fix the compressive deformation.•The treated wood showed improved density and dimensional stability.•The surface color of treated wood resembled that of hardwood commonly used in furniture.