Treesearch

The impact of jet cooking on shear strength of soy-and-water adhesives was investigated to understand the higher shear strength of commercial soy protein isolates compared to soy flours. Soy flour-based wood adhesives are appealing because of their bio-based content, low formaldehyde emission, and low cost, but their commercial application is limited by low wet cohesive strength. Previous researchers proposed that the process of jet cooking (steam injection with high turbulence followed by rapid cooling) was responsible for the high (∼3 MPa) wet shear strength of adhesives made with...

This paper addresses strengths, weaknesses, opportunities, and threats of the wood adhesives industry as discussed at the International Conference on Wood Adhesives in May 2022. The authors have organized the points made during the discussion and added further facts, assumptions, and conclusions to provide context and perspective, even surpassing the outcome of the discussion. The biggest themes of the discussion were the unprecedented opportunity for adhesives to enable forest products to supply society’s surging demand for renewable materials and the challenges in meeting those demands....

The combination of alkaline delignification and densification was applied to improve wood mechanical strength. Poplar wood samples were subjected to alkali delignification with varying degrees of lignin and hemicellulose removal followed by hot pressing. Dynamic mechanical performances and dynamic sorption behavior of the untreated and densified wood were then evaluated. Results showed that appropriate removal of lignin can improve the stiffness of densified wood and reduce moisture sorption and the numbers of sorption sites. Fourier transform infrared (FTIR) microscopy along with X-ray...

Accurate quality detection of hardwood logs can realize efficient utilization of wood and provide significant benefits to wood enterprises. However, due to the differences in the extraction principle of acoustic parameters and the interaction mechanism between the parameters and wood properties, the quality assessment results of hardwood logs are different to some extent. For this, a method for feature extraction of the acoustic signal and defect detection was proposed based on the improved particle swarm optimization-variational modal decomposition (IPSO-VMD). By analyzing the sparse...

A mass timber lateral force resisting system (LFRS) is proposed using a mass timber buckling restrained brace (TBRB) to improve the seismic resilience of mass timber buildings. To develop a resilient braced frame, it is essential to understand and quantify the behavior of the connections, including the possible failure modes and moment-rotation capacities. Cyclic and monotonic tests were conducted on six mass timber beam-column connections to study the response of a mass timber joint connected with slotted-in steel plates and mild steel dowels. The primary goal of the subassembly tests was...

Several material properties of wood are directionally dependent. Mechanical properties such as tension, compression, and bending strength vary greatly for the same piece of wood when tested parallel to the grain (longitudinally), perpendicular to the grain and parallel to the annual rings (tangentially), or perpendicular to both the grain and rings (radially). For this reason, wood is often considered to be a cylindrically orthotropic anisotropic material. The orthotropy extends to dielectric properties of wood. However, in the presence of internal decay, the directional dependency of the...

Each year, agricultural residues such as stalks, husks, and pits/nutshells from food crop harvesting are available on a gigatonne scale worldwide. While biorefinery routes have been used convert agricultural residue carbohydrates into value-added products (e.g., bioethanol, biochemicals), the lignin, comprising 20–50% of the dry mass of agricultural residues, remains largely underutilized. Therefore, there is an urgent need to explore the utilization of agricultural biorefinery lignins for value-added products. In this review, we briefly introduce the origins of agricultural lignins,...

The efficacy of a spray-on combination formula containing the insecticides thiamethoxam and chlorantraniliprole was tested against subterranean termites using a covered ground proximity test. The test consisted of six treatments, five were chemical treatments and one was water control. Southern pine wood samples were treated with varying rates or treatment methods of the aforementioned insecticide combination, chlorantraniliprole alone, borate alone, or no chemical (water) treatment. Treated samples were installed at the Harrison Experimental Forest in Saucier, Mississippi using a modified...

Thermally modified wood (TMW) is a growing trend in North America in areas of low decay and insect pressure. Thermal modification improves dimensional stability, decreases moisture uptake, and results in a darkened color that resembles tropical hardwoods. More testing is needed in severe decay situations and in areas of high termite pressure to fully understand the boundaries of its material performance. Within the AWPA, the P9 subcommittee (non-biocidal wood protectants) has been working to develop test methodologies and appropriate use category designations for TMW materials. The Forest...

Moisture-selective polymer-based membranes can be a promising method for energy saving in drying systems of different industries that vent moisture vapor-rich air to the atmosphere, such as wood drying, biorefinery, food processing, and pharmaceutical industry. Developing a sustainable product with bio-based materials reduces the environmental impacts. This study assessed the techno-economic feasibility and life-cycle environmental impacts of producing a novel cellulose nanocrystal/polydimethylsiloxane hybrid moisture-selective membrane. The cradle-to-gate assessment was facilitated by...