Optimizing rubberwood performance through rapid heated platen thermal modification: A sustainable approach for enhanced dimensional stability, decay resistance, and mechanical integrity

The global shift toward sustainable development has increased the demand for renewable biomass materials, with rubberwood emerging as a promising resource due to its rapid growth and potential for carbon sequestration. However, its susceptibility to dimensional instability and decay has significantly hindered its widespread industrial application. While current solutions address certain challenges, they often come with disadvantages such as high costs, inefficiencies, and/or environmental risks. This study introduces an innovative heated platen modification method designed to overcome these limitations. By employing direct-contact heating, a rapid surface modification is achieved between 5 and 15 min at temperatures ranging from 250 to 290 ℃. It creates a functionally graded material structure that enhances surface properties while maintaining core strength. Compared to untreated materials, the treated specimens exhibited a 524 kg/m³ increase in surface density, a 29–47 % reduction in modulus of rupture, a 2–11 % decrease in modulus of elasticity, a 2–31 % drop in screw holding power, a 33 % reduction in shrinkage, and a 58 % decrease in swelling. Surface natural decay resistance performance improved significantly, with a 39–45 % decrease in mass loss rate. Mechanistic analysis revealed that selective hemicellulose degradation and lignin redistribution enhanced the overall degree of crystallinity from 40 % to 64 % without compromising the crystalline domains, collectively improved dimensional stability and decay resistance without severe strength compromise. A key contribution of this study is establishing quantitative correlations between color parameters and performance metrics, revealing strong relationships between ΔE * and mechanical properties, chemical composition, and dimensional stability, and suggesting the chromatic indices as viable proxies for performance evaluation. However, predicting fungal durability via color requires further study due to decay mechanism complexities. This work advances the sustainable utilization of plantation species by integrating controlled surface modification, performance enhancement, and non-destructive assessment, offering a paradigm for efficient wood processing aligned with circular economy principles. • A rapid 15-minute platen treatment enhances rubberwood stability, reducing shrinkage by 58 %. • Color parameters ( ΔE */ b *) n predict properties (R² ≤ 0.902) for non-destructive testing. • An optimal treatment at 270 ℃ for 10 min boosts decay resistance, reducing fungal mass loss by 39 %.