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ABSTRACT Tall oil is one of the side products from the kraft pulping process of lignocellulosic material. The most abundant acid found in this crude viscous material is abietic acid. Strangely, in the past, the utilization of tall oil has been limited to incineration for cogeneration of power. In this study, tall oil rosin acids (TORAs) were used in two different applications. First, it was used to enhance the hydrophobicity and thermal properties of hemp fibers. Second, TORAs were used to supplement epoxy for the production of a polymeric material. The reaction conditions from a model study were mimicked using a crude tall oil rosin acid mixture to enhance hemp fibers. Treated hemp fibers were characterized with increased surface hydrophobicity and improved thermal properties. Also, IR and X-ray photoelectron spectroscopy confirmed successful chemical modification and grafting of carbon rich moieties onto the surface of the fibers, respectively. Furthermore, TORAs were used to supplement epoxy resin and produced plastics with comparable properties to pure epoxy based plastics. Specifically, 25% (w/w) replacement exhibited little difference in thermal stability and curing when compared to virgin epoxy plastics. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 44327. [ABSTRACT FROM AUTHOR]

The feasibility of employing chemical methods for enhancement of cellulose-based materials is dependent on the availability, price, and green index of the modifying agent. This study details the use of iodomethane, an inexpensive organo halide, to increase the hydrophobicity of thermo mechanical (TMP) samples, which renders them better structural elements for composite materials. For this system, we studied the influence of various concentration of iodomethane, concentration of caustic, and reaction time. Infrared spectroscopy suggested reaction of the organo halide with the hydroxyl groups of cellulose and lignin components of TMP. Pulp samples treated for 4 h or at low caustic concentration showed the least improvements plausibly due to pulp degradation or poor pulp swelling, respectively. On the other hand, pulp treated at 3 h using high concentrations of caustic were characterized with surfaces that were more hydrophobic. Thus, this study outlines a fast and organic solvent-free (clean up) method that can be used to enhance pulp samples for composite applications. [ABSTRACT FROM AUTHOR]

A method is proposed for producing fatty acid esters of thermomechanical pulp (TMP) using fatty acids of intermediate chain length (C6-C12). The end objective is to use a stream of fatty acids produced via refining tall oil from Alberta's pulping mills. Depending on the degree of modification, these treated materials can serve either as reinforcement or as copolymers in composite applications. The effect of reaction conditions—reaction time, reaction temperature, fatty acyl concentration, and fatty acid chain length—on the degree of substitution of the pulp samples was studied. The reaction conditions were applied for each fatty acyl chloride and the pulp samples were characterized using X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, force tensiometry, time-of-flight secondary ion mass spectroscopy, atomic force microscopy, and thermal gravimetric analysis. The degree of substitution (DS) plateaued after two hours at a concentration of 0.25 M of hexanoyl chloride. These conditions were used for the other systems studied. The esterification of the pulp samples was heterogeneous as evident from both the AFM and SIMS images, because of the presence of lignin on the surface. Nevertheless, based on adhesion forces measured using AFM, the surface of the modified pulp samples was less polar. This was also confirmed via contact angle measurements. Also, the changes in chemical functionality were studied using FTIR and XPS with the appearance of peaks characteristic of C˭O (esters) and an increase in intensity of the alkyl shifts, respectively. Finally, it was found that esterification significantly improved the thermal properties of the pulp samples. [ABSTRACT FROM PUBLISHER]

The aim of this study was to characterize the surface, morphological, and thermal properties of hemp fibers treated with two commercially available, inexpensive, and water soluble sulfonic acid derivatives. Specifically, the cellulosic component of the fibers were targeted, because cellulose is not easily removed during chemical treatment. These acids have the potential to selectively transform the surfaces of natural fibers for composite applications. The proposed method proceeds in the absence of conventional organic solvents and high reaction temperatures. Surface chemical composition and signature were measured using gravimetric analysis, X-ray photoelectron spectroscopy (XPS) and Fourier transform infra-red spectroscopy (FTIR). XPS data from the treated hemp fibers were characterized by measuring the reduction in O/C ratio and an increase in abundance of the C C O signature. FTIR confirmed the reaction with the emergence of peaks characteristic of disubstituted benzene and amino groups. Grafting of the sulfonic derivatives resulted in lower surface polarity. Thermogravimetric analysis revealed that treated fibers were characterized by lower percent degradation between 200 and 300 °C, and a higher initial degradation temperature. [ABSTRACT FROM AUTHOR]

The main aim of this study was to investigate the effect of mercerization prior to enzymatic treatments on the surface, on the thermal and morphological properties of hemp fibres. Hemp fibres were treated with sodium hydroxide (5%, w/v) and five different enzyme systems. The enzymes studied were xylanase, xylanase + 10% cellulase, pectinmethylesterase, polygalacturonase and laccase. A previous report utilizing enzymes alone ( George et al., 2014 ) was used as a baseline to determine the impact of caustic swelling of the hemp fibres coupled to enzymatic treatment. Thermal gravimetric analysis (TGA) was used to study the effect of each system on thermal properties of the hemp fibres. Scanning electron microscopy (SEM) was used to monitor the changes in the morphological features of the hemp fibres, while X-ray photoelectron spectroscopy (XPS) was used to study the influence of each treatment of the surface chemical composition. Force tensiometry was used to investigate the effect of the different systems on the surface polarity of the treated fibres. The additional treatment with NaOH + hemicellulases was found to result in enhanced thermal properties when compared to previous systems. SEM micrographs confirmed greater fibre bundle rupture and increase in surface roughness of the base + enzyme treated samples. This work demonstrates that mercerization prior to enzymes, depending on the mode of action and arrangement of chemical components of the fibre, can be an effective method for improving the thermal and surface properties of fibres for composite applications. [ABSTRACT FROM AUTHOR]

BACKGROUND As a result of the bovine spongiform encephalopathy ( BSE) emergence, certain tissues of cattle are categorized as specified risk material ( SRM) and completely banned from their traditional applications as an ingredient in animal feed, pet food, or fertilizer applications. The goal of this study was to investigate the hydrolysis of such hazardous proteinacious biomass and extract a safe proteinacious fraction to produce industrial feedstock for value-added applications. RESULTS The SRM was hydrolyzed at subcritical temperatures of 180, 200, 220, 240, and 260 °C for 40 min according to government-approved protocols. The recovery and cleavage of proteins and lipids, the generation and degradation of free and total amino acids, and the generation of organic acids were studied and found to be temperature-dependent. The yield of the hydrolyzed and recovered proteinacious fractions varied between 71.6 and 87.6% by weight of the original protein content in the SRM. The molecular size was also significantly dependent on the hydrolysis temperature. CONCLUSION The valorization of an otherwise waste SRM by subcritical hydrolysis and recovery techniques resulted in protein hydrolyzates suitable for bio-based chemicals and materials applications. The increase of temperature resulted in higher degrees of hydrolysis as shown by the smaller molecular size of hydrolyzed proteins. © 2014 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The primary goal of this research was to develop a waste protein based adhesive, and to optimize its lap shear strength under dry and wet conditions using Taguchi method. The feedstock for this work was specified risk material (SRM) that is considered the tissue potentially at risk of containing misfolded prions. SRM was hydrolyzed in accordance with government approved techniques and modified with a resin system to develop a renewable adhesive platform. Eight of the nine formulated adhesives met the minimum dry shear strength requirement of urea formaldehyde type adhesive, and three of the formulations also met the soak shear strength requirement. This work demonstrates a general valorization platform for the utilization of animal waste protein as a renewable adhesive feedstock. [ABSTRACT FROM AUTHOR]

The primary goal of this work was to develop a novel adhesive technology platform for oriented strand board (OSB) using waste animal protein extracts, as feedstock. In this research, a hazardous animal processing waste was thermally hydrolyzed, and the proteinaceous fractions were recovered and modified into an adhesive. The adhesive developed as such was formulated for OSB adhesion applications, and the OSB performance was also evaluated. Performance results showed that the OSB specimens made with up to 60% by weight of protein hydrolyzate based adhesive met the Canadian Standard Association (CSA O437.0-93) requirements for commercial applications. Based on the intermediate moisture resistance results observed, the recommended use of these boards could be for relatively low moisture environments. [ABSTRACT FROM AUTHOR]

Highlights: [•] Enzymatic treatments produced a homogeneous cellulose surface for subsequent activation. [•] Removal of thermally labile pectic and hemicellulosic content resulted in improved thermal stability. [•] The ultra structure of flax fibres (versus hemp) renders it more susceptible to enzymatic degradation. [ABSTRACT FROM AUTHOR]

The collapse of Langmuir monolayers of poly(vinyl stearate) (PVS) at the air-water interface has been investigated by combined measurements of the surface pressure-area isotherms and Brewster angle microscopy (BAM). Atomic force microscopy (AFM) has been used to gain out-of-plane structural information on collapsed films transferred onto a solid substrate by a modified version of the inverse Langmuir-Schaefer deposition method. At high areas per monomer repeat unit, BAM imaging revealed that the films are heterogeneous, with large solidlike domains (25-200 mum in diameter) coexisting with liquidlike domains. Upon film compression, the domains coalesced to form a homogeneous monolayer before the film collapsed at constant pressure, forming irreversible three-dimensional (3D) structures. BAM images showed that two 3D structures coexisted: buckles of varying width extending across the surface and perpendicular to the direction of the compression and dotted islandlike structures. Upon expansion, the film fractured and both 3D protrusions persisted, explaining the marked hysteresis recorded in the Langmuir isotherms. Experiments with AFM confirmed the 3D nature of both protrusions and revealed that many buckles contain substructures corresponding to narrow buckles whose heights are a multiple of a single bilayer. Additionally, many multilayer islands with diameters spanning from 0.2 mum to over 3.5 mum were characterized by varying heights between 2 nm and up to over 50 nm. The key to the formation of the irreversible 3D structures is the presence of large inhomogeneities in the PVS monolayer, and a generalized phenomenological model is proposed to explain the collapse observed.