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The current production of wood composites relies mostly on formaldehyde-based adhesives such as urea formaldehyde (UF) and phenol formaldehyde (PF) resins. As these resins are produced from non-renewable resources, and there are some ongoing issues with possible health hazard due to formaldehyde emission from such products, the purpose of this research was to develop a formaldehyde-free plywood adhesive utilizing waste protein as a renewable feedstock. The feedstock for this work was specified risk material (SRM), which is currently being disposed of either by incineration or by landfilling. In this report, we describe a technology for utilization of SRM for the development of an environmentally friendly plywood adhesive. SRM was thermally hydrolyzed using a Canadian government-approved protocol, and the peptides were recovered from the hydrolyzate. The recovered peptides were chemically crosslinked with polyamidoamine-epichlorohydrin (PAE) resin to develop an adhesive system for bonding of plywood specimens. The effects of crosslinking time, peptides/crosslinking agent ratio, and temperature of hot pressing of plywood specimens on the strength of formulated adhesives were investigated. Formulations containing as much as 78% (wt/wt) peptides met the ASTM (American Society for Testing and Materials) specifications of minimum dry and soaked shear strength requirement for UF resin type adhesives. Under the optimum conditions tested, the peptides-PAE resin-based formulations resulted in plywood specimens having comparable dry as well as soaked shear strength to that of commercial PF resin. [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 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]

The effects of salt, molecular weightand viscosity, and mass ratioon the apparent activation energy of the cross-linking reaction ofepoxy resins and protein hydrolysate were studied by nonisothermaldifferential scanning calorimetry. The Kissinger equation, the model-freeisoconversional method, and the autocatalytic model were used to analyzethe kinetic data. The presence of salts contributed to an increasein the apparent activation energy. The curing of epoxy resins withlower molecular weight protein hydrolysates was found to have loweractivation energy and order of reaction. An increase in the concentrationof curing groups resulted in a small increase in the order of reaction.The activation energy of curing bisphenol A diglycidyl ether (DGEBA),with viscosity 500–700 cP, was found to be significantly higherthan the curing activation energy of polypropylene glycol diglycidylether (PPGDE), which has a viscosity of 50 cP. [ABSTRACT FROM AUTHOR]

Highlights: [•] We characterized hydrolysates of cattle tissues known as specified risk materials. [•] We measured protein cleavage as function of hydrolysis protocol. [•] We identified the reactive functionalities available. [•] We suggested possible industrial applications. [ABSTRACT FROM AUTHOR]

Theeffects of salt, water, and temperature on the cross-linking of peptoneswith glutaraldehyde were studied. At low reaction temperatures, aminegroups from peptones form Schiff bases with carbonyl groups of glutaraldehyde.The resulting CN bond is weak and can be easily broken byheat or dissolution in water. As the reaction temperature is increased,the more stable CN bond is formed. A network with low watersolubility and significantly improved thermal stability is produced.The presence of salt (sodium chloride) increases the miscibility ofpeptones and glutaraldehyde solution but also increases the watersolubility of the final product. The presence of water also has adual effect. Water acts as a medium to disperse peptones into glutaraldehydeand is also a hydrogen source to drive the reaction forward. However,water is a byproduct of the reaction. Its presence suppresses thereaction from the standpoint of thermodynamic equilibrium, and itmust therefore be driven off (by heat). [ABSTRACT FROM AUTHOR]