In situ polymerization of PEGDA/MMA network in sliced wood for high flexibility and thermally induced shape memory functionality

Sliced wood veneer maintains the natural texture and color of wood, but its lack of flexibility and difficulty in shaping limit its potential applications. In this study, a modified sliced wood veneer was successfully fabricated by employing NaOH hydrothermal pretreatment and in situ polymerization with a reactive monomer solution of polyethylene glycol diacrylate (PEGDA) and methyl methacrylate (MMA), with FTIR, DMA, and SEM analyses performed to systematically reveal its chemical structure, thermomechanical behavior, and microscopic morphology. The results showed that the modified sliced wood veneer possessed excellent thermally induced shape memory properties, with a shape recovery ratio of 99.6% and a shape fixity ratio of 97.9%, retaining high recovery efficiency and fixed over 12 consecutive cycles. Moreover, in the transverse direction, the fracture diameter of the sliced veneer at 130 °C was reduced from 12.2 mm to 1.4 mm, indicating a significant enhancement in flexibility. The transverse and longitudinal tensile strengths of the modified sliced veneer were also improved by 37.3% and 12.9% by combining NaOH hydrothermal pretreatment and in situ polymerization, respectively. This approach improves the performance of wood and broadens the potential applications of sliced wood veneer in fields such as architecture, interior decoration, and transportation interiors.