Influence of macrostructural parameters on the physico-mechanical properties and post-recovery of densified Scots pine wood

Abstract

Abstract

This study investigates the effects of macrostructural parameters, particularly latewood proportion, on the physico-mechanical properties and post-recovery behaviour of Scots pine (Pinus sylvestris L.) wood subjected to partial delignification and radial densification. The latewood content ranged from 22.56% to 48.25%. Delignification resulted in a 27.1% reduction in lignin content, decreasing from 28.4% to 20.7%. Densification effectively doubled the wood's density, reaching 1056–1168 kg·m⁻³ in the delignified-densified (DD) group and 1008–1117 kg·m⁻³ in the delignified-furfurylated-densified (DFD) group. Brinell hardness increased from 16.06–24.99 N·mm⁻² in controls to 87.85–145.27 N·mm⁻² (DD) and 68.65–103.54 N·mm⁻² (DFD). Specimens with higher earlywood content exhibited greater compressibility and densification. While furfurylation slightly decreased maximum density and hardness, it significantly enhanced dimensional stability, reducing post-recovery dimensional variation after 48 hours to 2.54–4.84% in DFD compared to 4.50–9.23% in DD. Statistically significant correlations were observed among density, compression ratio, and hardness. The results demonstrate that anatomical structure substantially influences densification efficiency, and furfurylation improves short-term moisture stability.