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1.
Polymers (Basel) ; 15(18)2023 Sep 16.
Article in English | MEDLINE | ID: mdl-37765642

ABSTRACT

Due to the possible effects of global warming, new materials that do not have a negative impact on the environment are being studied. To serve a variety of industries and outdoor applications, it is necessary to consider the impact of photoluminosity on the performance of biocomposites in order to accurately assess their durability characteristics and prevent substantial damage. Exposure to photoluminosity can result in adverse effects such as discoloration, uneven surface, loss of mass, and manipulation of the intrinsic mechanical properties of biocomposites. This study aims to evaluate general charcoal from three pyrolysis temperatures to understand which charcoal is most suitable for photoluminosity and whether higher pyrolysis temperatures have any significant effect on photoluminosity. Porosity, morphology, Fourier transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy of charcoal were analyzed. Charcoal obtained at a temperature of 800 °C demonstrates remarkable potential as a bioreinforcement in polymeric matrices, attributable to its significantly higher porosity (81.08%) and hydrophobic properties. The biocomposites were characterized for flexural strength, tensile strength, scanning electron microscopy (SEM), FTIR, and x-ray diffraction (XRD). The results showed an improvement in tensile strength after exposure to photoluminosity, with an increase of 69.24%, 68.98%, and 54.38% at temperatures of 400, 600, and 800 °C, respectively, in relation to the treatment control. It is notorious that the tensile strength and modulus of elasticity after photoluminosity initially had a negative impact on mechanical strength, the incorporation of charcoal from higher pyrolysis temperatures showed a substantial increase in mechanical strength after exposure to photoluminosity, especially at 800 °C with breaking strength of 53.40 MPa, and modulus of elasticity of 4364.30 MPA. Scanning electron microscopy revealed an improvement in morphology, with a decrease in roughness at 800 °C, which led to greater adhesion to the polyester matrix. These findings indicate promising prospects for a new type of biocomposite, particularly in comparison with other polymeric compounds, especially in engineering applications that are subject to direct interactions with the weather.

2.
Polymers (Basel) ; 14(24)2022 Dec 16.
Article in English | MEDLINE | ID: mdl-36559891

ABSTRACT

Most composites produced come from fossil fuel sources. Renewable strategies are needed for the production of composites. Charcoal fines are considered waste and an alternative for the production of biocomposites. The charcoal fines resulting from the pyrolysis of any biomass are an efficient alternative for the production of green composites. Studies to understand how the pyrolysis parameters influence the properties of this material for the production of biocomposites are necessary. Charcoal has a high carbon content and surface area, depending on final production temperatures. This study aims to evaluate charcoal fines as potential reinforcing agents in biocomposites. This study investigated for the first time charcoal fines from three pyrolysis temperatures (400, 600, and 800 °C) to identify the most suitable charcoal for use as a raw material in the production of carbon biocomposites with 30% by weight incorporated into a polyester matrix composite. Apparent density, porosity, morphology, and immediate chemical composition and Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) of charcoal fines were evaluated. The charcoal fines produced at 800 °C showed interesting potential as polymeric matrix fillers due to their higher porosity (81.08%), fixed carbon content (96.77%), and hydrophobicity. The biocomposites were analyzed for flexural and tensile strength and scanning electron microscopy. The results revealed an improvement in resistance at elevated temperatures, especially at 800 °C, with higher breaking strength (84.11 MPa), modulus of elasticity (4064.70 MPa), and traction (23.53 MPa). Scanning electron microscopy revealed an improvement in morphology, with a decrease in roughness at 800 °C, which caused greater adhesion to the polyester matrix. These results revealed a promising new biocomposite compared to other natural lignocellulosic polymeric composites (NLFs) in engineering applications.

3.
Polymers (Basel) ; 13(12)2021 Jun 15.
Article in English | MEDLINE | ID: mdl-34203736

ABSTRACT

Commercial wood adhesives are based on products that contain formaldehyde; however, environmental and health concerns about formaldehyde emissions from wood products have influenced research and development efforts in order to find alternative, formaldehyde-free products for wood adhesives. In this work, different soy protein-based wood adhesives are proposed, and their performance is compared to commercial urea formaldehyde (UF) adhesive. Soy protein-based wood adhesives were prepared using either soy protein isolate (SPI) or soy protein flour (SF) with different coadjutant polymers: polyethylene oxide (PEO), hydroxypropyl methylcellulose (HPMC), cellulose nanofibrils (CNF) or polyvinyl alcohol (PVA) with and without addition of kraft lignin. The effects of the type of soy protein, solids content, coadjutant polymer and lignin addition were investigated. The wood adhesive formulations were tested on the bonding of hardwood (white maple) and softwood (southern yellow pine) and the dry shear strength of test specimens was measured according to method ASTM D905-08. The adhesive formulations with SPI achieved significantly higher values than those with SF. The dry shear strength of the adhesives varies depending on the coadjutant polymer, the wood species and the addition of lignin.

4.
J Colloid Interface Sci ; 381(1): 171-9, 2012 Sep 01.
Article in English | MEDLINE | ID: mdl-22721790

ABSTRACT

A new approach based on microemulsions formulated with at least 85% water and minority components consisting of oil (limonene) and surfactant (anionic and nonionic) is demonstrated for the first time to be effective for flooding wood's complex capillary structure. The formulation of the microemulsion was based on phase behavior scans of Surfactant-Oil-Water systems (SOWs) and the construction of pseudo-ternary diagrams to localize thermodynamically stable one-phase emulsion systems with different composition, salinity and water-to-oil ratios. Wicking and fluid penetration isotherms followed different kinetic regimes and indicated enhanced performance relative to that of the base fluids (water, oil or surfactant solutions). The key properties of microemulsions to effectively penetrate the solid structure are discussed; microemulsion formulation and resultant viscosity are found to have a determining effect in the extent of fluid uptake. The solubilization of cell wall components is observed after microemulsion impregnation. Thus, the microemulsion can be tuned not only to effectively penetrate the void spaces but also to solubilize hydrophobic and hydrophilic components. The concept proposed in this research is expected to open opportunities in fluid sorption in fiber systems for biomass pretreatment, and delivery of hydrophilic or lipophilic moieties in porous, lignocellulosics.


Subject(s)
Cyclohexenes/chemistry , Oils/chemistry , Surface-Active Agents/chemistry , Terpenes/chemistry , Water/chemistry , Wood/chemistry , Emulsions , Hydrophobic and Hydrophilic Interactions , Kinetics , Limonene , Porosity , Thermodynamics , Viscosity , Wettability
5.
Sensors (Basel) ; 10(11): 10401-12, 2010.
Article in English | MEDLINE | ID: mdl-22163477

ABSTRACT

Wood processing industries have continuously developed and improved technologies and processes to transform wood to obtain better final product quality and thus increase profits. Abrasive machining is one of the most important of these processes and therefore merits special attention and study. The objective of this work was to evaluate and demonstrate a process monitoring system for use in the abrasive machining of wood and wood based products. The system developed increases the life of the belt by detecting (using process monitoring sensors) and removing (by cleaning) the abrasive loading during the machining process. This study focused on abrasive belt machining processes and included substantial background work, which provided a solid base for understanding the behavior of the abrasive, and the different ways that the abrasive machining process can be monitored. In addition, the background research showed that abrasive belts can effectively be cleaned by the appropriate cleaning technique. The process monitoring system developed included acoustic emission sensors which tended to be sensitive to belt wear, as well as platen vibration, but not loading, and optical sensors which were sensitive to abrasive loading.


Subject(s)
Optical Devices , Wood , Acoustics , Environmental Monitoring
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