Meriem Fehri^1,2, Rachid Robleh Ragueh¹, Alexandre Vivet^1*, Fakhreddine Dammak², Mohamed Haddar²

Journal of Renewable Materials, Vol.5, No.1, pp. 38-47, 2017, DOI:10.7569/JRM.2016.634123

Abstract The purpose of this work is the improvement of flax fiber-reinforced composites obtained by vacuum molding in order to encourage their insertion into industrial products. The relatively high degree of porosity in these kinds of composites, due to the lack of compatibility between epoxy matrix and flax fibers and the hydrophilicity of flax fiber, remains a major constraint to their use in the industrial world. Hence, we have used a combination of carbon fibers with those of flax in order to optimize the properties of the assembly. Several stacking sequences have been tested in order to analyze the influence of… More >

Miguel Ángel Ramírez¹, Patricia González², Juan Reinerio Fagundo², Margaret Suarez³, Clara Melian³, Tania Rodríguez¹, Carlos Peniche^4*

Journal of Renewable Materials, Vol.5, No.1, pp. 30-37, 2017, DOI:10.7569/JRM.2016.634121

Abstract The inorganic components of crustacean shells are usually removed using HCl solutions. This provokes undesirable modifications in the extracted chitin. In the present procedure, deproteinized lobster shells were demineralized with CO2 and a cationic resin (cationite). The resulting chitin (CHI-CO2) is compared in terms of degree of acetylation (DA), crystallinity index (CrI) and thermal stability with chitins obtained by demineralization procedures with HCl (CHI-HCl) and ethylenediaminetetraacetic acid (CHI-EDTA). The ash content of chitins demineralized with CO2 was similar to that of chitins prepared using HCl or EDTA. However, the resultant DA and CrI of CHI-HCl and CHI-EDTA were lower than… More >

M. Thébault^1,2, A. Pizzi1^3*, F.J. Santiago-Medina¹, F.M. Al-Marzouki³, S. Abdalla³

Journal of Renewable Materials, Vol.5, No.1, pp. 21-29, 2017, DOI:10.7569/JRM.2016.634116

Abstract Isocyanate-free polyurethane resins biosourced to a very high percentage level were prepared by the reaction of aminated mimosa tannin extract with commercial mimosa tannin extract prereacted with dimethyl carbonate. The reaction took place with ease at ambient temperature. Indications were that the polyurethanes obtained formed a hard film when cured at a temperature higher than 100 °C. Furthermore, the carbohydrate fraction of the tannin extract also appeared to be carbonated and reacted to generate isocyanate-free polyurethane linkages with the aminated tannins. This indicated that not only the polyphenolic fraction of the tannin extract, but also its other major component, can… More >

S.K. Pankaj¹, C. Bueno-Ferrer¹, N.N. Misra¹, L. O’Neill², Paula Bourke¹, P.J. Cullen^3*

Journal of Renewable Materials, Vol.5, No.1, pp. 14-20, 2017, DOI:10.7569/JRM.2016.634105

Abstract This work aims to analyze the effects of cold atmospheric air plasma treatment of antimicrobial chitosan film with different levels of thymol. Optical characterization of the dielectric barrier discharge showed the generation of reactive nitrogen and oxygen species by the system. A significant increase (p < 0.05) in the surface roughness was observed after cold plasma treatment of the films. No significant difference (p > 0.05) was observed in the thermal profile of the plasma-treated films. A significant increase (p < 0.05) in the thymol diffusion coefficient was observed after the plasma treatment for all the active films. More >

Heather L. Buckley^1*, Caitlin H. Touchberry², Jonathan P. McKinley², Zachary S. Mathe¹, Hurik Muradyan¹, Hannah Ling², Raj P. Fadadu¹, Martin J. Mulvihill¹, Susan E. Amrose²

Journal of Renewable Materials, Vol.5, No.1, pp. 1-13, 2017, DOI:10.7569/JRM.2016.634109

Abstract Waste cardboard is an underutilized resource that can be redirected for the creation of safer and higher quality building materials for low-income housing in the developing world, as well as to produce better materials for indoor environments in developed-world contexts. Using a renewable biobased binder and benign additives, we have improved the water resistance of a cardboard-based composite material, overcoming one of the major barriers to scaling and adoption of this class of materials. Resistance to water uptake was significantly increased with several additives and was increased over 900-fold in the best case. Strength and water uptake over time are… More >

Mingzhe Jiang¹, S. Nicole DeMass¹, D. Ross Economy², Thomas Shackleton¹, Christopher L. Kitchens^1*

Journal of Renewable Materials, Vol.4, No.5, pp. 377-387, 2016, DOI:10.7569/JRM.2016.634131

Abstract Spin coating was used to cast a uniform film of cellulose nanocrystals with low surface roughness and variable thickness as a function of operational parameters that include rotational speed and dispense suspension concentration. The film thickness was controllable from 40 nm up to 1 μm with surface roughness an order of magnitude less than blade-coating methods. The degree of radial orientation was qualitatively assessed and shown to be variable with processing parameters. Under specific processing conditions, the formation of striation patterns was observed and associated with film drying instability. The striation patterns are periodic in nature where the wavelength and… More >

Mehdi Tajvidi^1*, Douglas J. Gardner², Douglas W. Bousfield³

Journal of Renewable Materials, Vol.4, No.5, pp. 365-376, 2016, DOI:10.7569/JRM.2016.634103

Abstract A novel application of cellulose nanomaterials, particularly cellulose nanofibrils (CNF) as a binder in conventional and novel laminate and particulate composite systems is discussed. Using cellulose nanomaterials as a reinforcing agent in conventional polymer composites faces several difficulties: 1) there are no easy ways to dry the CNF and maintain nanoscale dimensions, 2) there are compatibility issues related to cellulose-polymer bonding, and 3) there are issues related to obtaining a good distribution and redispersion of nanoscale materials inside a polymer matrix. An alternative strategy is applications in which cellulose nanomaterials can be used in the aqueous suspension form without first… More >

Jithin Joy^1,2,3, Cintil Jose³, Srirama B. Varanasi⁴, Lovely Mathew P.^2,3, Sabu Thomas², Srikanth Pilla^1,5*

Journal of Renewable Materials, Vol.4, No.5, pp. 351-364, 2016, DOI:10.7569/JRM.2016.634128

Abstract Isora nanofibers (INF) were produced by a combined thermal-chemical-mechanical method from Helicteres isora plant. The resulting fibers were analyzed using transmission electron microscopy and scanning electron microscopy, which showed a network-like structure with a length of 600 nm, width of 50 nm and an aspect ratio of 12. Fourier transform infrared spectroscopy indicated that chemical treatments progressively removed noncellulosic constituents. X-ray diffraction analysis revealed that crystallinity increased with successive chemical treatments. Using the synthesized isora nanofibers, poly(butylene succinate) (PBS)-based biodegradable nanocomposites were prepared. The nanocomposites were processed using a Brabender twin-screw compounder and an injection molding machine. Effects of INF… More >

Jose Luis Orellana, Michael Mauhar, Christopher L. Kitchens^*

Journal of Renewable Materials, Vol.4, No.5, pp. 340-350, 2016, DOI:10.7569/JRM.2016.634126

Abstract Polylactic acid (PLA) is one of the most widely used biodegradable polymers due to the ability to synthesize it economically at industrial scale and its favorable properties for many consumer products. However, the rigid nature of PLA is not desirable for specific applications, requiring the incorporation of effective bioderived additives in order to enhance the PLA toughness and broaden applications. In this work, PLA was modified by graft polymerization of polyacrylic acid (PLA-g-PAA) to increase the hydrophilicity to promote compatibilization of cellulose nanocrystals (CNCs) or high molecular polyethylene glycol (PEG). CNCs were found to act as a nucleating agent for… More >

Craig Clemons

Journal of Renewable Materials, Vol.4, No.5, pp. 327-339, 2016, DOI:10.7569/JRM.2016.634112

Abstract Continuous fibers are commonly manufactured for a wide variety of uses such as filters, textiles, and composites. For example, most fibrous reinforcements (e.g., carbon fiber, glass fiber) for advanced composites are continuous fibers or yarns, fabrics, and preforms made from them. This allows broad flexibility in design and manufacturing approaches by controlling fiber orientation and architecture. However, there has been growing interest in preparing continuous fibers from biobased materials such as plants. Of particular recent interest are nanocelluloses, which are projected to be less expensive than many other nanomaterials and have the potential to be produced in large volumes. They… More >