Acetylation of Never-Dried Wood via Diffusion-Driven Solvent Exchange

This dataset contains measurement data from the following publication:

Sultan M.T., Valkonen M., Awais M., Nousiainen P., Lillqvist K., Wang S., Rautkari L. Acetylation of Never-Dried Wood via Diffusion-Driven Solvent Exchange. Biomacromolecules 2026. https://doi.org/10.1021/acs.biomac.6c00768

ABSTRACT

Acetylation is one of the most widely applied chemical modification methods for enhancing the dimensional stability and durability of wood. In this work, we investigate a diffusion-driven solvent-exchange method for acetylating never-dried Scots pine wood, eliminating the energy-intensive drying typically required before wood acetylation. Results from two-dimensional confocal Raman microspectroscopic imaging, coupled with multivariate data analysis and high-performance liquid chromatography, suggest a uniform distribution of acetyl groups within the cell walls and increased lignin acetylation using the solvent-exchange method. The uniform distribution of acetyl groups and increased lignin modification in the cell corners and the middle lamella resulted in less shrinkage and much-improved antiswelling efficiency at the macroscale. Overall, this diffusion-driven solvent-exchange pretreatment provides a uniform, direct acetylation of never-dried wood, bypassing the conventional oven- or kiln-drying step, with targeted lignin modification playing a crucial role in controlling wood-water interactions.

Data Description

Methodological details can be found in the associated publication. The research data has been collated into a ZIP folder.

The "Delignified wood ATR-FTIR.opju" (OriginLab Corp. OriginPro) and "Delignified wood ATR-FTIR.xlsx" (Microsoft Corp. Excel) files contain the baseline (BL) -corrected and/or normalized (NLBC) attenuated total reflectance Fourier-transform infrared spectra and spectral data of the delignified specimens. The data are presented as wavenumbers [cm⁻¹] and absorbance [a.u.]. The OriginPro file contains relevant plots of the data with specimen labels, and the Excel file (in separate sheets) matches the supplementary material of the publication.

The "Histogram of lignin and acetyl.opju" and "Histogram of lignin and acetyl.xlsx" files contain the pixel intensities [–] for acetyl groups and lignin-related information, obtained per sample section from the Raman imaging data, with the OriginPro file containing the relevant plots. The Excel data has been separated into sheets per sample section label. The labels match the publication.

The "Mean Raman spectra.opju" and "Mean Raman spectra.xlsx" files contain the baseline-corrected (BLC) and/or NLBC mean Raman spectral data obtained from the cell walls (CWs) or cell corners (CCs) per sample section or delignified (DCW) specimen during the Raman imaging. The data are presented as Raman shifts [cm⁻¹] and Raman intensities [a.u.]. The OriginPro file contains the relevant plots, whereas the Excel file has been split into sheets per sample section or specimen label. The labels match the publication.

The "Principal component analysis.opju" and "Principal component analysis.xlsx" files contain the results of the principal component analysis in terms of Raman shift [cm⁻¹] and loading vector values [–] for the selected principal components. The OriginPro file contains the relevant plots, and the Excel file includes representative plots and the image mosaics of the components. There are also statistical details on the principal components and clustering data, along with relevant plots, in the Excel file. The labels match the publication and its supplementary material.

The "Raman microspectroscopy data" folder contains the raw and cosmic-ray-removed data from the Raman imaging. The WiRE data file (WDF) names match the sample section or specimen labels, and "CR" stands for "cosmic ray". The WDF files can be preliminarily analyzed with the "renishawWire.m" MATLAB (Matrix Laboratory) [The MathWorks, Inc.] function and are compatible with the WiRE (Windows-based Raman Environment) software by Renishaw plc. Related description: RenishawWire is a MATLAB function that reads Renishaw WiRE version 3 .wdf files and extracts the Raman shift axis, intensity data (as a height by width by Raman shift hypercube), map dimensions, acquisition date, and axis labels. It supports single spectra, multiple spectra, and hyperspectral images, with optional plotting. This function was used to import raw Renishaw Raman data into MATLAB for the analysis reported in the publication, and the function has been archived here for reproducibility and ease of access. This function is the original work of Alex Henderson (University of Manchester) and is distributed under the GNU General Public License v3.0. The canonical version is available at https://bitbucket.org/AlexHenderson/renishaw-file-formats. All rights and credit remain with the original author.

The "Saponification calculation 1.1.xlsx" file contains (A, first sheet) the basic chemical analysis data and parameters of wood acetyl group determination by saponification and (B, second sheet) the same for holocellulose acetyl group determination by saponification. It is presented using common wood materials science and chemical engineering symbols and parameters, which are readily understood by anyone with experience in these fields. Some key data have also been averaged and plotted in the file. N.B. The file has been patched for a minor issue.

The "Solvent exchange file 1.1.xlsx" file contains (A, first sheet) the mass- and dimension-based basic measurement data obtained during or after the pre-treatments, acetylation reactions, and characterizations, and (B, second sheet) the details of the dimensional stability measurement data. It is presented using common wood materials science and chemical engineering symbols and parameters, which are readily understood by anyone with experience in these fields. Some key data have also been averaged and plotted in the file. N.B. The file has been patched for a minor issue.

The "Wood ATR-FTIR.opju" and "Wood ATR-FTIR.xlsx" files contain the NLBC attenuated total reflectance Fourier-transform infrared spectra and spectral data of the wood pellets. The data are presented as wavenumbers [cm⁻¹] and absorbance [a.u.]. The OriginPro file contains relevant plots of the data with specimen labels, and the Excel file (in separate sheets) matches the publication.