Surfactant-Induced Reconfiguration of Urea-Formaldehyde Resins Enables Improved Surface Properties and Gluability of Bamboo

Abstract

The high-efficiency development and utilization of bamboo resources can greatly alleviate the current shortage of wood and promote the neutralization of CO2. However, the wide application of bamboo-derived products is largely limited by their unideal surface properties with adhesive as well as poor gluability. Herein, a facile strategy using the surfactant-induced reconfiguration of urea-formaldehyde (UF) resins was proposed to enhance the interface with bamboo and significantly improve its gluability. Specifically, through the coupling of a variety of surfactants, the viscosity and surface tension of the UF resins were properly regulated. Therefore, the resultant surfactant reconfigured UF resin showed much-improved wettability and spreading performance to the surface of both bamboo green and bamboo yellow. Specifically, the contact angle (CA) values of the bamboo green and bamboo yellow decreased from 79.6° to 30.5° and from 57.5° to 28.2°, respectively, with the corresponding resin spreading area increasing from 0.2 mm2 to 7.6 mm2 and from 0.1 mm2 to 5.6 mm2. Moreover, our reconfigured UF resin can reduce the amount of glue spread applied to bond the laminated commercial bamboo veneer products to 60 g m−2, while the products prepared by the initial UF resin are unable to meet the requirements of the test standard, suggesting that this facile method is an effective way to decrease the application of petroleum-based resins and production costs. More broadly, this surfactant reconfigured strategy can also be performed to regulate the wettability between UF resin and other materials (such as polypropylene board and tinplate), expanding the application fields of UF resin.

Surface Characteristics of Phenolic Resin Coatings

“…This could correspond to the presence of additional C --O bonds (see Figs. S6-S8 in the SI) [67]. Peak broadening was best seen for PF-TEA coatings, where the FWHM of the O 1 s spectra increased on average from 1.6 eV to 2.0 eV.…”

Enhancing Crack and Mold Resistance of Bamboo by In Situ Construction of Shape Memory Epoxy/Poly(furfuryl alcohol) Bioresin

“…Chemical modification is an effective method to improve dimensional stability, crack resistance, mold resistance, and thermal and mechanical performance of bamboo materials. Treatment with low molecular weight monomers or precursors, such as methyl methacrylate (MMA), phenolic resin, urea formaldehyde resin, 1,3-dimethylol-4,5-dihydroxyethyleneurea (DMDHEU), and epoxy resin (EP), which can easily polymerize or cure inside or on the surface of bamboo, has been proved as highly efficient and simple ways to enhance the multifaceted properties of bamboo. − Wood or bamboo modified with unsaturated monomers or formaldehyde-based thermosetting resins exhibit enhanced strength, dimensional stability, and resistance against microorganisms compared with untreated ones. , However, the volatilization of unreacted monomer or formaldehyde during use threatens the environment and human health. As one of the most versatile thermosetting resins, the EP possessing typical advantages of easy processing, excellent adhesion, good dimensional, thermal stability, and shape memory performance has already been widely utilized as adhesives, coatings, and matrices in various fields. − Currently, Chen et al modified bamboo with 2,3-epoxypropyl trimethylammonium chloride cationization and rosin acid impregnation, where the water repellency and mold-proof properties of bamboo were improved .…”