Open Access

ARTICLE

Environmentally Friendly Tannic Acid-Furfuryl Alcohol-Soybean Isolate/Casein Composite Foams Reinforced with Wood Fibers

Jinxing Li¹, Mustafa Zor², Xiaojian Zhou³, Guanben Du³, Denis Rodrigue⁴, Xiaodong (Alice) Wang^1,*

1 Department of Wood and Forest Sciences, Laval University, Québec, G1V 0A6, Canada
2 Department of Nanotechnology, Zonguldak Bülent Ecevit University, Zonguldak, 67900, Turkey
3 Yunnan Provincial Key Laboratory of Wood Adhesives and Glued Products, Southwest Forestry University, Kunming, 650224, China
4 Department of Chemical Engineering, Laval University, Québec, G1V 0A6, Canada

* Corresponding Author: Xiaodong (Alice) Wang. Email:

Journal of Renewable Materials 2025, 13(2), 329-347. https://doi.org/10.32604/jrm.2024.056795

Received 31 July 2024; Accepted 16 October 2024; Issue published 20 February 2025

Abstract

In this study, two series of foams based on tannic acid (TA), furfuryl alcohol (FA), soybean protein isolate (SPI), and casein (CA), namely TA–FA–SPI (TS series) and TA–FA–CA (TC series) were developed, and their properties were enhanced by adding poplar fibers (WF). From the samples produced, a complete set of characterization was performed including possible crosslinking reactions, morphology, mechanical properties, flame retardancy, thermal insulation and thermal stability. Fourier-transform infrared spectroscopy (FTIR) revealed possible covalent crosslinking among the components and hydrogen bonding between WF and the matrix. Viscosity results indicated that lower prepolymer viscosity led to lower apparent density, while WF addition reduced even more the density. Mechanical tests showed that the maximum compressive strengths were good, while WF improved the compressive strength by up to 56%. Scanning electron microscopy (SEM) showed uniform cell structures, but small open pores were observed. Two-dimensional (2D) CT scan images confirmed the good compatibility between WF and the matrix, with low anisotropy in the material. Friability tests indicated that WF decreased the pulverization ratio of the materials by up to 42%. Thermogravimetric analysis (TGA) showed good thermal stability of the materials up to 328°C. Vertical burning tests showed that the materials were self-extinguishing without residue (dripping). The lowest thermal conductivity was 0.04 W/m·K. These results suggest that these novel formaldehyde-free, high biomass content (95%–96%) foams and composite foams have high potential to replace traditional phenolic foams (PF) in applications such as construction, transportation, packaging, and thermal insulation.

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Keywords

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