Properties of High-Density Fiberboard Bonded with Urea–Formaldehyde Resin and Ammonium Lignosulfonate as a Bio-Based Additive

Abstract

The potential of ammonium lignosulfonate (ALS) as an eco-friendly additive to urea–formaldehyde (UF) resin for manufacturing high-density fiberboard (HDF) panels with acceptable properties and low free formaldehyde emission was investigated in this work. The HDF panels were manufactured in the laboratory with very low UF resin content (4%) and ALS addition levels varying from 4% to 8% based on the mass of the dry wood fibers. The press factor applied was 15 s·mm−1. The physical properties (water absorption and thickness swelling), mechanical properties (bending strength, modulus of elasticity, and internal bond strength), and free formaldehyde emission were evaluated in accordance with the European standards. In general, the developed HDF panels exhibited acceptable physical and mechanical properties, fulfilling the standard requirements for HDF panels for use in load-bearing applications. Markedly, the laboratory-produced panels had low free formaldehyde emission ranging from 2.0 to 1.4 mg/100 g, thus fulfilling the requirements of the E0 and super E0 emission grades and confirming the positive effect of ALS as a formaldehyde scavenger. The thermal analyses performed, i.e., differential scanning calorimetry (DSC), thermal gravimetric analysis (TGA), and derivative thermogravimetry (DTG), also confirmed the main findings of the research. It was concluded that ALS as a bio-based, formaldehyde-free adhesive can be efficiently utilized as an eco-friendly additive to UF adhesive formulations for manufacturing wood-based panels under industrial conditions.

Influence of the Structure of Lattice Beams on Their Strength Properties

“…They can be OSB, fibreboards or other modern boards [ 39 ]. This is in line with the current trend of the use of eco-friendly wood-based panels in construction [ 40 , 41 ].…”

Characterization of Thermal Bio-Insulation Materials Based on Oil Palm Wood: The Effect of Hybridization and Particle Size

“…They reported that bio-based adhesives of lignin, starch, and tannins can potentially be used to produce eco-friendly wood composite materials. Furthermore, some researchers have extensively studied the potential utilization of lignosulfonates to produce eco-friendly particleboard [ 32 , 33 , 34 ]. Several research groups have used tapioca starch as a bio-binder in bio-insulation materials, including ramie fiber [ 35 ], sugarcane bagasse [ 36 ], water hyacinth [ 37 ], bamboo [ 25 , 38 ], and oil palm empty fruit bunches (OPEFB) [ 39 ].…”

Mechanical Properties and Formaldehyde Release of Particleboard Made with Lignin-Based Adhesives

“…The contribution of lignosulfonates to the performance of the engineered wood panels is presented in several papers. Calcium lignosulfonate [38] magnesium and sodium lignosulfonates [39], ammonium lignosulfonate [40][41][42] or modified ammonium lignosulfonate [43] were used as adhesives for lowering formaldehyde emission and improve the mechanical properties of the panels. A mixture of phenol formaldehyde adhesives and lignosulfonate (up to 20% of lignosulfonate in the adhesives) was shown to improve the shear strength of wood glued joints gradually [44].…”