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 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… More >

Nicole M. Stark

Journal of Renewable Materials, Vol.4, No.5, pp. 313-326, 2016, DOI:10.7569/JRM.2016.634115

Abstract Performance requirements for packaging films may include barrier properties, transparency, flexibility, and tensile strength. Conventional packaging materials, such as plastic films and laminates, are typically made from petroleum-based polymers. Currently, there is a drive to develop sustainable packaging materials. These alternative materials must be able to be manufactured economically and on a commercial scale, exhibit barrier properties and transparency, and provide adequate mechanical performance. As a biobased, renewable material, cellulose nanomaterials (CNs) are ideally suited to be used in sustainable packaging applications. CNs include cellulose nanocrystals (CNCs) and cellulose nanofibrils (CNFs) and each can provide More >

Ronald Sabo^1*, Aleksey Yermakov², Chiu Tai Law³, Rani Elhajjar⁴

Journal of Renewable Materials, Vol.4, No.5, pp. 297-312, 2016, DOI:10.7569/JRM.2016.634114

Abstract Cellulose nanomaterials have a number of interesting and unique properties that make them well-suited for use in electronics applications such as energy harvesting devices, actuators and sensors. Cellulose nanofibrils and nanocrystals have good mechanical properties, high transparency, and low coefficient of thermal expansion, among other properties that facilitate both active and inactive roles in electronics and related devices. For example, these nanomaterials have been demonstrated to operate as substrates for flexible electronics and displays, to improve the efficiency of photovoltaics, to work as a component of magnetostrictive composites and to act as a suitable lithium More >

Craig Clemons, Srikanth Pilla

Journal of Renewable Materials, Vol.4, No.5, pp. 295-296, 2016, DOI:10.7569/JRM.2016.634133

Abstract Cellulose nanomaterials (CNs) are at the convergence of nanotechnology and bio-sourced material trends and are currently of considerable interest. CNs are a new class of nano-scale, cellulose-based building blocks extracted from trees and plants as well as certain animals, bacteria, and algae. CNs are not a single material type but a family of materials with different characteristics, which largely result from differences in source and preparation methodology. Here we focus on plant- and tree-derived CNs. More >

A. Ivdre^1*, G.D. Soto², U. Cabulis¹

Journal of Renewable Materials, Vol.4, No.4, pp. 285-293, 2016, DOI:10.7569/JRM.2016.634122

Abstract This study presents the synthesis of novel polyols made from tall oil (TO) and poly(ethylene terephthalate) (PET) with different TO/PET molar ratios. Rigid polyurethane foams based on these synthesized polyols were obtained and characterized to evaluate polyols’ suitability for the development of light materials with insulating properties. The effect of TO/PET molar ratios on the physical, morphological and mechanical properties of the obtained foams, as well as their thermal insulation characteristics, were evaluated. Increasing amounts of PET in polyurethane foams resulted in higher compression strength and closed cell content, while water absorption was not affected. More >

Facundo I. Altuna¹, Borja Fernández-d’Arlas², M. Angeles Corcuera², Arantxa Eceiza², Mirta I. Aranguren³, Pablo M. Stefani^3*

Journal of Renewable Materials, Vol.4, No.4, pp. 275-284, 2016, DOI:10.7569/JRM.2016.634120

Abstract Mixtures of biomass-derived polyols were used to synthesize rigid polyurethane (PU) foams. A commercial polymerized methylene diphenyl diisocyanate (pMDI) was used as crosslinker, and distilled water served as foaming agent. The morphology and mechanical properties of foams with different glycerol and water contents were compared in order to evaluate the most suitable formulations. The rigid foams with higher water contents had larger and more anisotropic cells, explaining their lower density. Compressive moduli ranged from about 2.5 MPa to above 20 MPa and collapse stresses from 55 kPa to more than 1 MPa for densities between More >

Piotr Rojek², Mirta I. Aranguren¹, Aleksander Prociak², Mirna A. Mosiewicki^1*

Journal of Renewable Materials, Vol.4, No.4, pp. 266-274, 2016, DOI:10.7569/JRM.2016.634113

Abstract Solid biobased polyurethanes (PUs) were prepared from a rapeseed oil-based polyol (ROPO) synthesized by epoxidation reaction followed by oxirane ring-opening with diethylene glycol. The reference material was modified by replacement of the ROPO with glycerol in different proportions and also by addition of commercial microcellulose (MC). The curing process of the reactive mixtures was monitored by rheological measurements and the analysis showed that both MC and glycerol increase the time of crossover between storage and loss modulus (liquid to solid transition in the response at 1 Hz). The completely cured polyurethanes were characterized by physical, More >

Juan P. Correa^1,2*, Alejandro Bacigalupe^2,3, Jorge Maggi⁴, Patricia Eisenberg^2,3

Journal of Renewable Materials, Vol.4, No.4, pp. 258-265, 2016, DOI:10.7569/JRM.2016.634117

Abstract Poly(lactic acid)/poly(butylene adipate-co-terephthalate) (PLA/PBAT)-based nanocomposites were prepared by melt blending of PLA and PBAT with 5 wt% of unmodified (Cloisite Na) and modified (Cloisite 30B) montmorillonites. X-ray diffraction (XRD) revealed an intercalated structure in both nanocomposites. The extent of the intercalation was higher for nanocomposites based on modified clays (OMMT) with chemical affinity with the polymer matrix. Rheological measurements have shown an increase in viscosity and a better degree of clay dispersion for nanocomposites containing OMMT. Nanocomposites with OMMT showed lower PBAT separated phase particle size and improvements in thermal stability, mechanical properties and water More >

M. L. Lambri^1,2, E. D. Giordano^2,3, P. B. Bozzano⁴, F. G. Bonifacich², J. I. Pérez-Landazábal^5,6, G. I. Zelada², D. Gargicevich², V. Recarte^5,6, O. A. Lambri^2*

Journal of Renewable Materials, Vol.4, No.4, pp. 251-257, 2016, DOI:10.7569/JRM.2016.634111

Abstract The denaturation processes of collagen in the temperature range between 450 K and 670 K are revealed through studies performed on cow rib bones by means of mechanical spectroscopy, differential scanning calorimetry, thermogravimetry, scanning electron microscopy and infrared spectroscopy. The conformational change of the collagen molecules from a triple helix structure to a random coil was found at around 510 K. It was determined that the transformation is developed through the viscous movement of fibrils with an activation energy of (127 ± 8) kJ/mol. The second stage of massive bulk deterioration of the collagen was More >