Oscar F. Aguilar Gutierrez, Alejandro D. Rey^*

Journal of Renewable Materials, Vol.4, No.4, pp. 241-250, 2016, DOI:10.7569/JRM.2016.634119

Abstract Biological plywoods are solid analogues of liquid crystalline phases whose building blocks, including cellulose, collagen and chitin, present multifunctionality, providing in some cases protection, camouflage, self-healing and/or adaptability to the surrounding environment. The 3D ordered structure is the main factor for these fascinating properties, and the assessment of the structure-property relationship will be a powerful tool in terms of future material design and innovation. Cross-section observations lead to characteristic patterns depending on the specific arrangement of the plywood’s building blocks. Twisted plywood architectures, known as the Bouligand structure, lead to the widely observed arced patterns which can be ideal or… More >

Mirta Inés Aranguren, Arantxa Eceiza

Journal of Renewable Materials, Vol.4, No.4, pp. 239-239, 2016, DOI:10.7569/JRM.2016.634125

Abstract There is an increasing awareness among the general public of the importance of the intelligent use of earth’s biological resources for the production of chemicals, materials and precursors, resulting in an economy that is turning towards considering the valuable contributions offered by these resources. To face the present challenges of reducing the use of nonrenewable resources and the negative impact of polymer pollution on the environment, the world’s scientists are making their contribution by unraveling biological structures and studying and developing new materials and applications from biomass resources. More >

Evelien Uitterhaegen^1,2, Quang Hung Nguyen^1,2, Othmane Merah^1,2, Christian V. Stevens³, Thierry Talou^1,2, Luc Rigal^1,2, Philippe Evon^1,2*

Journal of Renewable Materials, Vol.4, No.3, pp. 225-238, 2016, DOI:10.7569/JRM.2015.634120

Abstract New fiberboards were manufactured from a coriander cake through thermo-pressing, and the influence of thermo-pressing conditions (temperature, pressure and time) on the boards’ mechanical properties, their thickness swelling and their water absorption was evaluated. Because the protein glass transition systematically occurred during molding, this resulted in effective wetting of the fibers. Consequently, all boards were cohesive, with proteins and fibers acting as binder and reinforcing fillers, respectively. Flexural properties were influenced by all tested conditions, and the optimal board was molded at 200 °C temperature, 36.8 MPa pressure and 180 s time. Its flexural strength at break and its elastic… More >

Arunjunairaj Mahendran^1*, Günter Wuzella¹, Thomas Hardt-Stremayr¹, Wolfgang Gindl-Altmutter²

Journal of Renewable Materials, Vol.4, No.3, pp. 215-224, 2016, DOI:10.7569/JRM.2016.634110

Abstract Woven natural fiber-reinforced composites were fabricated using four different flax fabrics and two biobased epoxy resin matrices. The reinforced composites were prepared using resin infusion technique and fiber volume fractions of between 28–35% were achieved using this method. The fiber matrix interaction and the failure mechanism in the composite were observed using scanning electron microscopy. The flexural strength and modulus on the warp and weft directions were characterized and it was found that based on yarn count and yarn thickness change in the flexural strength was observed. Dynamic water absorption and thickness swelling were observed for a certain period of… More >

Mercedes Echegaray¹, Gurutz Mondragon¹, Loli Martin², Alba González³, Cristina Peña-Rodriguez¹, Aitor Arbelaiz^1*

Journal of Renewable Materials, Vol.4, No.3, pp. 206-214, 2016, DOI:10.7569/JRM.2016.634106

Abstract Organic rodlike cellulose nanocrystals extracted from sisal fibers and inorganic montmorillonite based on silicate layers were employed to develop bionanocomposites based on gelatin matrix. Bionanocomposites with cellulose nanocrystal, montmorillonite and both nanoreinforcements combined were characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis and differential scanning calorimetry. Tensile properties and oxygen and water vapor gas permeability values were determined to study the influence of the addition of nanoreinforcements, different in nature, to gelatin matrix. Bionanocomposites with montmorillonite improved tensile strength but systems reinforced with nanocellulose showed lower tensile strength than neat gelatin ones. Oxygen gas permeability values decreased for all bionanocomposites,… More >

D. Puglia^1*, F. Dominici¹, M. Badalotti², C. Santulli³, J.M. Kenny¹

Journal of Renewable Materials, Vol.4, No.3, pp. 199-205, 2016, DOI:10.7569/JRM.2016.634102

Abstract In this work, cocoa bean shells (CBS), which were ground, then sieved to less than 150 μm and dried in a vacuum oven, have been introduced in a polycaprolactone (PCL) matrix in three different amounts, 10, 20 and 30% wt. The obtained composites were tested under tensile loading, which indicated an enhanced rigidity with a slight decrease of strength with respect to the neat polymer and a reduced elongation, particularly evident for composites with 30 wt% CBS, where final collapse took place for strains only slightly exceeding the yielding point. Differential scanning calorimetry (DSC) indicated a rather negligible variation of… More >

F. Luzi, E. Fortunati^*, D. Puglia, R. Petrucci, J.M. Kenny, L. Torre

Journal of Renewable Materials, Vol.4, No.3, pp. 190-198, 2016, DOI:10.7569/JRM.2015.634134

Abstract In this research, the revalorization of Posidonia oceanica leaf sea waste was studied and the acid hydrolysis processing times were modulated in order to optimize the extraction of cellulose nanocrystals (CNCs). The obtained CNCs were deeply investigated. A two-step treatment was applied to extract cellulose nanocrystals from Posidonia oceanica leaves. First, a chemical treatment leads to the removal of lignin and production of holocellulose, while the second chemical process of acid hydrolysis allows the obtainment of cellulose nanocrystals in aqueous suspension. The unbleached and bleached leaves and cellulose nanocrystals were characterized by using thermogravimetric analysis, infrared spectroscopy and morphological investigation;… More >

Karina Cruz-Aldaco¹, Erika Flores-Loyola², Cristóbal Noé Aguilar-González¹, Nuria Burgos³, Alfonso Jiménez^3*

Journal of Renewable Materials, Vol.4, No.3, pp. 178-184, 2016, DOI:10.7569/JRM.2016.634107

Abstract The use of vegetable oils to replace fossil feedstock has become an area of opportunity and a priority for study in the field of polymer science. Vegetable oils are considered as renewable resources with high potential, low cost and full availability. The aim of this study is the synthesis of biobased polyols from cottonseed oil (Gossypium barbadanse) and corn oil (Zea mays) as feedstock. Their synthesis was successfully performed, as can be concluded from the determination of their hydroxyl index as well as the structural and thermal characterization carried out in this work. Polyurethanes from biobased polyols were synthesized with… More >

Nuria Burgos, Arantzazu Valdés, Alfonso Jiménez^*

Journal of Renewable Materials, Vol.4, No.3, pp. 165-177, 2016, DOI:10.7569/JRM.2016.634108

Abstract In this study we provide an overview of the latest developments on the extraction, production, modification and applications of fruit residues and by-products in the formation of protein-based biopolymers, in particular for the formulation of edible films. Our aim was mainly to demonstrate the highly transdisciplinary character of these topics by giving an overview of the main developments and research topics in the chemistry and engineering aspects of protein-based biopolymers. These innovative raw materials have been evaluated for the production of biomaterials to be used in some key sectors, such as food packaging. More >

Alfonso Jiménez, Arantxa Eceiza, José M. Kenny

Journal of Renewable Materials, Vol.4, No.3, pp. 163-164, 2016, DOI:10.7569/JRM.2016.634118

Abstract The articles included in this Special Issue of the Journal of Renewable Materials are a selection of those presented at the 5th International Conference on Biobased and Biodegradable Polymers (BIOPOL-2015) that was held in Donostia-San Sebastián, Spain, in October 2015. More >