Approaching Self-Bonded Medium Density Fiberboards Made by Mixing Steam Exploded L. and Wood Fibers: A Comparison with pMDI-Bonded Fiberboards on the Primary Properties of the Boards.

This study presents an unexplored method to produce formaldehyde-free MDF. Steam exploded L. (STEX-AD) and untreated wood fibers (WF) were mixed at different mixing rates (0/100, 50/50, and 100/0, respectively) and two series of boards were manufactured, with 4 wt% of pMDI, based on dry fibers, and self-bonded.

Loofah Sandwich Panels: The Effect of Adhesive Content on Mechanical and Physical Properties.

In the development of new materials, the focus nowadays is increasingly on their relevance with regard to lightweight construction or environmental compatibility. The idea of a lightweight sandwich panel was inspired by an increasing number of cosmetic accessories that use the fibers of the loofah plant, a rapidly renewable, light, fibrous raw material. The aim of the study was to develop a fiber composite panel based on the fibers of the loofah plant () as core material and wooden veneer as the skin layer to be used in areas of lead construction.

Seagrass Leaves: An Alternative Resource for the Production of Insulation Materials.

Seagrass wracks, the remains of dead leaves accumulated on seashores, are important ecosystems and beneficial for the marine environment. Their presence on the touristic beaches, however, is a problem for the tourism industry due to the lack of aesthetics and safety reasons. At the present time, seagrass leaves are landfilled, although this is not considered an ecological waste management practice.

Vacuum Low-Temperature Microwave-Assisted Pyrolysis of Technical Lignins.

Cleavage by microwave-assisted pyrolysis is a way to obtain higher-value organic chemicals from technical lignins. In this report, pine kraft lignin (PKL), spruce and beech organosolv lignin (SOSL and BOSL), and calcium lignosulfonates from spruce wood (LS) were pyrolyzed at temperatures between 30 and 280 °C using vacuum low-temperature, microwave-assisted pyrolysis. The mass balance, energy consumption, condensation rate, and pressure changes of the products during the pyrolysis process were recorded.

Bonding Acetylated Veneer for Engineered Wood Products-A Review.

The purpose of this review is to put previous research findings on acetylated wood and the fabrication of veneer-based products in a common context. The first research on wood acetylation was already conducted in the 1920s using wood meal, whereas relevant research on veneer acetylation was published nearly two decades later, during the 1940s. In the years that followed, a great deal of research has been done on both solid wood and composite acetylation.

Lignin and Lignin-Derived Compounds for Wood Applications-A Review.

Improving the environmental performance of resins in wood treatment by using renewable chemicals has been a topic of interest for a long time. At the same time, lignin, the second most abundant biomass on earth, is produced in large scale as a side product and mainly used energetically. The use of lignin in wood adhesives or for wood modification has received a lot of scientific attention.

Determination of fungal activity in modified wood by means of micro-calorimetry and determination of total esterase activity.

Beech and pine wood blocks were treated with 1,3-dimethylol-4,5-dihydroxyethylen urea (DMDHEU) to increasing weight percent gains (WPG). The resistance of the treated specimens against Trametes versicolor and Coniophora puteana, determined as mass loss, increased with increasing WPG of DMDHEU. Metabolic activity of the fungi in the wood blocks was assessed as total esterase activity (TEA) based on the hydrolysis of fluorescein diacetate and as heat or energy production determined by isothermal micro-calorimetry.

Degradation of acrylic copolymers by white-rot fungi.

Various water-soluble homopolymers and copolymers of acrylamide (AAm) and acrylic acid (AA) which contained phenolic sites, such as guaiacol, lignin sulfonate (LS) and 3,4-dihydroxybenzoic acid (3,4-DHBA), were tested with regard to their degradability by white-rot fungi. Compared with Phanerochaete chrysosporium, Pleurotus ostreatus caused a significantly higher decrease in the average molecular weight ( Mw) of most of the copolymers and the homopolymer under the applied culture conditions. However, the Mw of poly(guaiacol/AAm) increased significantly during incubation with Pl ostreatus.

Lignification and structural biomass production in tobacco with suppressed caffeic/5-hydroxy ferulic acid-O-methyl transferase activity under ambient and elevated CO concentrations.

To investigate the relationship between growth, biomass partitioning and lignification we used tobacco (Nicotiana tabacum) in which O-methyl transferase (OMT) activity, an enzyme involved in the pathway of sinapyl alcohol formation for lignin synthesis, was suppressed by antisense transformation. To modulate growth, controls and transformed tobacco plants were grown under ambient (approximately 380 p.p.

Elevated pCO affects N-metabolism of young poplar plants (Populus tremula × P. alba) differently at deficient and sufficient N-supply.

•  The effects of N-availability and elevated atmospheric CO partial pressure ( pCO ) on growth, allometry and N-metabolism of poplar plants are reported here. •  Poplar plants were grown hydroponically at deficient and sufficient N-supply under ambient and elevated pCO . The N-fluxes within the plants were estimated by comparing the fate of newly acquired N-NO in plants either severely N-limited or with sufficient N-supply.