Exploring the potential of high resolution mass spectrometry for the investigation of lignin-derived phenol substitutes in phenolic resin syntheses

Abstract

Chemical degradation is an efficient method to obtain bio-oils and other compounds from lignin. Lignin bio-oils are potential substitutes for the phenol component of phenol formaldehyde (PF) resins. Here, we developed an analytical method based on high resolution mass spectrometry that provided structural information for the synthesized lignin-derived resins and supported the prediction of their properties. Different model resins based on typical lignin degradation products were analyzed by electrospray ionization in negative ionization mode. Utilizing enhanced mass defect filter techniques provided detailed structural information of the lignin-based model resins and readily complemented the analytical data from differential scanning calorimetry and thermogravimetric analysis. Relative reactivity and chemical diversity of the phenol substitutes were significant determinants of the outcome of the PF resin synthesis and thus controlled the areas of application of the resulting polymers. Graphical abstract ᅟ.

Rapid mass spectral fingerprinting of complex mixtures of decomposed lignin: Data‐processing methods for high‐resolution full‐scan mass spectra

“…Our research focused on the MS study of highly complex lignin mixtures of oxygen‐containing compounds resulting from the electrochemical breakdown process . We demonstrated the proof‐of‐concept of using HRMS for these mixtures and utilized appropriate data‐processing and ‐mining techniques for analysis (Figure ) …”

“…The 2D mass defect matrix plot can also be extrapolated to the study of many other NOM, for example, phenol formaldehylde resins, where the phenol component could be obtained from biooils from lignin. In the modified 2D plot (Figure ), the data points along the y ‐axis belong to the same polymer category with varying number of formaldehyde units (KMD = C 6 H 4 O) . Starting at the KMD for an unsubstituted catechol monomer (★) and following the line vertically along the y ‐axis, four subsequent m/z features follow the straight line.…”

“…B) Enlarged area of the catechol‐rich region. Reprinted from Dier et al, with permission from Springer Publishing…”

Constellation: An Open-Source Web Application for Unsupervised Systematic Trend Detection in High-Resolution Mass Spectrometry Data

“…In a follow-up study, similar visualization techniques were applied to the analysis of lignin-based model resins. 14 Again, by modifying the Kendrick mass scales to suit the target analytes, they were able to achieve clear visualizations for components belonging to various compound classes, gaining deep insight into the composition of very complex mixtures.…”

Lignin and Lignin-Derived Compounds for Wood Applications—A Review

“…However, due to the complex mixture it is often not possible to obtain a bio-oil that does not also contain molecules that worsen the resins' characteristics [80]. Dier et al (2017) [82] tested the influence of model bio-oils with different ratios of monomers on the characteristics of the resols. As in the study by Biziks et al (2020), it was found that bio-oils that contain cresols have high potential to replace phenol in PF resins, while catechols negatively impacted the properties of the resin [82].…”