Fungal decay-provoked degradation of cross-linking networks in phenol-formaldehyde adhesive: From fragmentation process towards damaged mechanical robustness
Year: 2024
Type: article
Abstract: The mechanical robustness of structural adhesives as represented by phenol formaldehyde (PF) adhesive is vital for the safe service of engineered wood/bamboo products facing environmental aggressors. Here, fungal decay-provoked hazard towards the mechanical robustness of PF adhesive was demonstrated, which was usually overlooked in previous works. Obtained results proved that the white rot (Trametes versicolor, T. versicolor) and brown rot (Gloeophyllum trabeum, G. trabeum) fungus can both grow on the surface of cured commercial PF adhesive. An evident oxidization can only be observed on the T. versicolor-infected PF adhesive, as along with the appearance of 2,6-bis(1,1-dimethylethyl)-1,4-benzenediol after infection. It further demonstrated the ruptured and oxidized cross-linking structures. The evident degradation of PF adhesive can be assigned to the favored activity of laccase (40.9 U·ml-1) and lignin peroxidase (60.5 U·ml-1) during T. versicolor infecting. The elastic modulus and hardness of PF adhesive reduced by over 31.6% and 50.2%, respectively, which is also accompanied by the elevation in the creep deformation (45.4%), after a 40-day T. versicolor infection. This work revealed the decay-sensitivity of PF adhesive, and the cleavage of cross-linking structures is the major trigger for the degraded mechanical robustness of PF adhesive after decay infection.
Source: Polymer Testing
Authors: Ran Yang, Shuwei Xu, Hui Wang, Xinxing Wu, Shuaibo Han, Chunde Jin, Fangli Sun, Yizhong Cao, Qiang Wu
Institution: Zhejiang A & F University
Language: English
Subfield: Building and Construction
Field: Engineering
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $2,580
OpenAlex ID: W4402623986