Galia Moreno, Karla Ramirez, Marianelly Esquivel, Guillermo Jimenez*

Journal of Renewable Materials, Vol.7, No.1, pp. 9-20, 2019, DOI:10.32604/jrm.2019.00017

Abstract Poly(lactic acid) (PLA) composite films reinforced with microcrystalline cellulose (MCC) extracted from pineapple leaf fibers (PALF) were prepared by a solution casting procedure. In an attempt to improve the interaction between PLA and cellulose, two approaches were adopted; first, poly(ethylene glycol) (PEG) was used as a surfactant, and second, the cellulosic fibers were pre-treated using tert-butanol (TBA). Lignocellulosic and cellulosic substrates were characterized using Fourier transform infrared (FTIR), wide-angle X-ray scattering (WAXS), and thermogravimetrical analysis (TGA). MCC from PALF showed good thermal stability, left few residues after decomposing, and exhibited high crystallinity index. Mechanical, thermal and thermomechanical properties of the… More >

A. Atiqah¹, M. Jawaid^1,*, S. M. Sapuan^1,2, M. R. Ishak³

Journal of Renewable Materials, Vol.6, No.5, pp. 477-492, 2018, DOI:10.7569/JRM.2017.634188

Abstract The aim of the present study was to develop sugar palm fiber (SPF) reinforced thermoplastic polyurethane (TPU) composites and to investigate the effects of fiber surface modification by 2% silane treatment and fiber loading (0, 10, 20, 30, 40 and 50 wt%) on the mechanical and thermal properties of the obtained composites. Surface treatment was employed to improve the fiber-matrix interface, which was expected to boost the mechanical strength of the composites, in terms of tensile, flexural and impact properties. Thermal properties were also investigated by thermal gravimetric analysis (TGA) and dynamic mechanical analysis (DMA) to assess the thermal stability… More >

S. Michałowski¹, M. A. Mosiewicki^2*, M. Kuran´ska¹, M. I. Aranguren², A. Prociak¹

Journal of Renewable Materials, Vol.6, No.4, pp. 426-437, 2018, DOI:10.7569/JRM.2017.634163

Abstract Elastomeric polyurethanes were prepared from a reference polyurethane system modified with biobased polyols synthesized using rapeseed or palm oils. The reference material was modified by replacement of the commercial polyol by 10% of biopolyols and also by addition of sisal fibers up to 5 wt%. The higher functionality of the biopolyols increased the crosslinking density of the networks and this was reflected by an increase in hardness and a decrease in water absorption. The effect of the sisal fibers mainly improved the mechanical and thermomechanical properties of the system with rapeseed oil because of good dispersion and strong fiber-matrix interaction.… More >

Dounia Bendahou^1,2, Abdelkader Bendahou¹, Bastien Seantier¹, Bénédicte Lebeau³, Yves Grohens^1,*, Hamid Kaddami^2,*

Journal of Renewable Materials, Vol.6, No.3, pp. 299-313, 2018, DOI:10.7569/JRM.2017.634185

Abstract Hybrid aerogels have been prepared by freeze-drying technique after mixing water dispersions of cellulose microfibers or cellulose nanofibers and silica (SiO2) of type SBA-15 (2D-hexagonal). The prepared composites were characterized by different analysis techniques such as SEM, hot-filament, DMA, etc. These composites are compared to those previously prepared using nanozeolites (NZs) as mineral charge. The morphology studied by SEM indicated that both systems have different structures, i.e., individual fibers for cellulose microfibers WP-based aerogels and films for nanofibrillated cellulose NFC-based ones.... These differences seem to be driven by the charge of the particles, their aspect ratio and concentrations. These hybrid… More >

Rajendran Muthuraj, Abhishek Sachan, Mickael Castro*, Jean-François Feller, Bastien Seantier*, Yves Grohens

Journal of Renewable Materials, Vol.6, No.3, pp. 277-287, 2018, DOI:10.7569/JRM.2017.634182

Abstract In this work, thermally insulating and electrically conductive aerogels were prepared from cellulose nanofibers (CNF) and carbon nanotubes (CNTs) by environmentally friendly freeze-drying process. The thermal conductivity of neat CNF aerogel is 24 mW/(m·K) with a density of 0.025 g/cm3. With the addition of CNTs into CNF aerogel, the electrical conductivity was significantly increased while the thermal conductivity was increased to 38 mW/(m·K). Due to these interesting properties, the Seebeck coefficient and the figure of merit (ZT) of the CNF/CNTs aerogels were measured and showed that CNF/CNTs aerogel thermoelectric properties can be improved. The compressibility and electrical resistance of the… More >

Maxime Pontié^1*, Serge Foukmeniok Mbokou^1,2, Jean-Philippe Bouchara¹, Bienvenue Razafimandimby¹, Sylvie Egloff¹, Ornella Dzilingomo¹, Pierre-Yves Pontalier³, Ignas Kenfack Tonle<

Journal of Renewable Materials, Vol.6, No.3, pp. 242-250, 2018, DOI:10.7569/JRM.2017.634169

Abstract Electrochemical determination of paracetamol (PCT) was successfully performed using carbon paste electrodes (CPEs) modified with treated coffee husks (CHt) or cellulose powder (Ce). Scanning electron microscopy was used to characterize unmodified or modified CPEs prior to their use. The electrochemical oxidation of PCT was investigated using square wave voltammetry (SWV) and cyclic voltammetry (CV). The oxidation current density of PCT was two-fold higher with the CPE-CHt sensor and 30% higher with CPE-Ce in comparison with the unmodified CPE, and this correlated with the higher hydrophilicity of the modified electrodes. Using SWV for the electrochemical analysis of PCT, carbon paste electrode… More >

G. Mondragon, C. Peña-Rodriguez, A. Eceiza, A. Arbelaiz^*

Journal of Renewable Materials, Vol.5, No.5, pp. 345-356, 2017, DOI:10.7569/JRM.2017.634124

Abstract In this work, the main chemical reactions conditions of a succession of specific chemical treatments used for the isolation of nanocellulose from sisal fibers were evaluated. The novelty of this work is the study done to analyze the effect of different reaction conditions (time or concentration) in fiber structure and composition as well as in the characteristics of obtained cellulosic samples. In order to achieve this goal different physicochemical, thermal and morphological characterization techniques were used after each chemical treatment and the most suitable reaction conditions were selected for the subsequent treatment. Moreover, the thermal stability evolution of cellulose nanocrystals… More >

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 >

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 >

Syed A Jamal^*

Molecular & Cellular Biomechanics, Vol.10, No.4, pp. 267-273, 2013, DOI:10.3970/mcb.2013.010.267

Abstract Human Umbilical Cord Mesenchymal Stem Cells (hUCMSCs) were subjected to in vitro osteogenic differentiation using a novel combination of signaling molecules including BMP-2 and purmorphamine. Differentiation outcomes were assessed by calcein staining and by microscopic examination of the cytoskeleton. Calcein staining showed appreciable degree of calcium mineralization in cell culture, and changes in the morphological attributes of differentiating cells were observed vis-a-vis the actin cytoskeleton. Finally, positive calcein staining, altered cytoskeletal profile, and stress fiber formation in treated cells demonstrated, for the first time, a potentially synergistic interplay between BMP-2 and the hedgehog agonist, purmorphamine. This study lends support to… More >