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n-Butyl acrylate and other acrylic monomers were copolymerized with an acrylated macromonomer to produce polymers for pressure-sensitive adhesive (PSA) applications. Macromonomers were generated through the ring-opening copolymerization of L-lactide and ε-caprolactone with 2-hydroxyethyl methacrylate (HEMA) at an average molar composition of 5:4:1, respectively. Conversion in the mini-emulsion polymerization was followed using Raman spectroscopy and was nearly complete within 2 h. Testing of these adhesive polymers indicates that performance properties meet or exceed those of commercial...

Forests are significant stores of carbon (C). This has been recognised by the United Nations Framework Convention on Climate Change and forests are one of the sectors which are included in national greenhouse gas (GHG) inventories. Some of this C pool remains in wood after harvest and can remain in use for long periods of time. Accounting for the C stored in harvested wood products (HWP) can potentially contribute to GHG mitigation. A model was developed for this research to estimate C stocks and flows in HWP in Ireland for the years 1961e2009. The change in carbon stocks in HWP were...

Southern yellow pine (Pinus taeda) wood char powder was thermally treated at 1,000°:C in the presence of a 25-nm-size Fe nanoparticle catalyst. The thermally treated carbon materials were analyzed by Raman spectroscopy and high-resolution transmission electron microscopy. Well-aligned graphitic carbon structures with 15 to 17 layers on average were observed. These graphitic carbon structures were similar to those of graphite with an average interplanar distance of 0.34 nm. The Raman spectra results showed that the full-width half-maximum values of Raman G and D bands, and the peak...

This report has been reviewed in draft form by persons chosen for their diverse perspectives and technical expertise in accordance with procedures approved by the National Research Council’s Report Review Committee. The purpose of this independent review is to provide candid and critical comments that will assist the institution in making the published report as sound as possible and to ensure that it meets institutional standards of objectivity, evidence, and responsiveness to the study charge. The review comments and draft manuscript remain confidential to protect the integrity of the...

It is well documented that temperature and humidity can influence formaldehyde emissions from composite panels that are produced using urea-formaldehyde (UF)–type adhesives. This work investigates the effect of temperature and humidity on newer commercial California Air Resources Board (CARB) phase II–compliant particleboard produced with UF-type adhesives. These results were compared with laboratory particleboards prepared with the no-added-formaldehyde (NAF) Soyad adhesive technology. A modified version of EN 717-3 (‘‘Formaldehyde Release by the Flask Method,’’ ÖNORM 1996) was used to...

Shear-based film casting methods were used to cast neat films from wood-based cellulose nanocrystal (CNC) suspensions. The degree of CNC alignment in dried films was characterized using the Hermans order parameter (S), and the film elastic modulus (E), ultimate tensile strength (σf ), elongation at failure (εf), and work of fracture (WF) were measured with respect to casting direction and CNC alignment. The degree of CNC alignment in dried films was found to increase with higher casting shear rates (0, 10∙s-1, and 100∙s-1) and at higher suspension pH (~3 versus ~7). The maximum orientation...

The Gram-positive bacterium Paenibacillus sp. JDR-2 (PbJDR2) has been shown to have novel properties in the utilization of the abundant but chemically complex hemicellulosic sugar glucuronoxylan. Xylanase A1 of PbJDR2 (PbXynA1) has been implicated in an efficient process in which extracellular depolymerization of this polysaccharide is coupled to assimilation and intracellular metabolism. PbXynA1is a 154 kDa cell wall anchored multimodular glycosyl hydrolase family 10 (GH10) xylanase. In this work, the 38 kDa catalytic module of PbXynA1 has been structurally characterized revealing several...

We investigate through-thickness hardness and modulus of Zr50Cu45Al5 metallic glass melt-spun ribbon. Because of their thinness, the ribbons are challenging to measure, so we employ a novel nanoindentation based-method to remove artifacts caused by ribbon flexing and edge effects. Hardness and modulus vary approximately linearly across the thickness but, unlike bulk ingots, the side of the ribbon that cooled most quickly had the highest hardness and modulus. This “inverse” variation may be caused by the fast-moving solidification front, which might conceivably, for instance, push free...

Wood specific gravity (SG) has long been used by foresters as an index for wood properties. More recently, SG has been widely used by ecologists as a plant functional trait and as a key variable in estimates of biomass. However, sampling wood to determine SG can be problematic; at present, the most common method is sampling with an increment borer to extract a bark-to-pith core—a difficult task requiring considerable physical effort and sometimes repeated borings to hit the pith, with potential to damage the trunk of small trees. Here, we test a novel sampling method that reduces the...

Using natural cellulosic fibers as fillers for biodegradable polymers can result in fully biodegradable composites. Biodegradable composites were prepared using nanofibrillated cellulose (NFC) as the reinforcement and poly (3-hydroxybutyrate-co-3-hydroxyvalerate, PHBV) as the polymer matrix. The objective of this study was to determine how various additives (i.e., blending PHBV with chain extender (CE) and/or Ecovio—a commercially available PLA/PBAT blend) affect the mechanical properties of injection molded PHBV/NFC nanocomposites. Tensile test bars of PHBV/NFC nanocomposites were...