Due to compatibility issues between traditional reinforcing materials and the substrate of museum wooden artifacts, interface failure occurs after crack reinforcement, particularly under dry and wet cycling conditions. This significantly compromises the durability of reinforcement. To resolve this issue, dealkalized lignin was grafted onto epoxy acrylate (LEA) to synthesize a novel consolidant with both humidity responsiveness and mechanical compatibility. The resulting LEA exhibited excellent multilayer adsorption capability and demonstrated synchronous and uniform hygroscopic expansion behavior, closely matching that of archeological wood. DMA revealed that LEA2 has an elastic modulus of 261.58 MPa and a Poisson’s ratio of 0.35, comparable to artificially degraded wood, effectively mitigating interface stress caused by rigidity differences. Furthermore, LEA effictively reinforced micron-scale cracks while maintaining the original microstructure of the wooden artifact. This material provides a promising solution to the compatibility challenges of traditional consolidants under humidity fluctuations and offers a new approach for the stable preservation of museum wooden artifacts.

The Qianlong Tripitaka preserved in the Capital Museum is a distinctive large-scale wood block printing plates of the Qing Dynasty. It represents a unique type of Chinese documentary wooden heritage preserved in a dry museum environment, which has rarely been subjected to comprehensive physicochemical analysis, resulting in an inadequate understanding of their deterioration processes. This study applied a comprehensive multi-analytical method to investigate the deterioration of the scripture plates. The findings indicate that the Qianlong Tripitaka shows typical structural deformation, chemical depolymerization, and a decline in structural integrity and stability. Scanning Electron Microscopy (SEM) and Computed Tomography (CT) revealed thinning and the distortion of cell walls, reduced density, and partial collapse of tissue structures. Thermogravimetric Analysis (TGA) indicated lower decomposition temperatures and higher inorganic residues, while a Brunauer–Emmett–Teller surface area analyzer (BET) showed diminished surface area, expanded pores, and compromised connectivity. Moisture content analyses verified significant water loss, contributing to brittleness and susceptibility to microbial degradation. Fourier Transform Infrared Spectroscopy (FTIR) and X-ray Diffraction (XRD) analyses revealed considerable hemicellulose degradation, the disruption of cellulose crystallinity, and relatively stable lignin. This study highlights the value of a multi-analytical strategy for assessing the deterioration of wooden cultural heritage, providing a transferable framework for similar documentary wooden artifacts.