Bernal Sibaja^1,2,3, Camila Pereira Matheus^1,2, Ricardo Ballestero Mendez^1,2,Ramsis Farag^1,2,4, J. R. Vega-Baudrit³, Maria L. Auad^*,1,2

Journal of Renewable Materials, Vol.5, No.3-4, pp. 241-250, 2017, DOI:10.7569/JRM.2017.634114

Abstract The thermo-mechanical properties and linear fracture mechanics of acrylated soybean oil and the triglycidylated ether of α-resorcylic acid interpenetrated networks as a function of their weight composition are the focus of Part 2 of this article. Thermo-mechanical characterization showed that the obtained materials behave as thermoset amorphous polymers, and that both the modulus and glass transition are extremely dependent on the epoxy/acrylate weight ratio. Modulus values ranged from 0.7 to 3.3 GPa at 30 °C, and glass transition temperatures ranged from around 58 °C to approx. 130 °C. No synergistic effect on these two properties More >

Bernal Sibaja^1,2,3, Camila Pereira Matheus^1,2, Ricardo Ballestero Mendez^1,2, J. R. Vega-Baudrit³, Maria L. Auad^*,1,2

Journal of Renewable Materials, Vol.5, No.3-4, pp. 231-240, 2017, DOI:10.7569/JRM.2017.634113

Abstract Interpenetrating polymer networks (IPNs) using an epoxy phase synthesized from chemically modified α-resorcylic acid, and an acrylate phase employing acrylated soybean oil are the main focus of this study. Part 1 details the epoxidation of α-resorcylic acid with epichlorohydrin in alkaline medium, as well as the study of the polymerization and network formation of the generated epoxy-acrylate interpenetrated systems. The epoxy content of the epoxidized α-resorcylic acid was measured by means of a titration using HBr in acetic acid solution, and the functionalization was studied by FTIR. From the obtained results, mainly calorimetry and gel More >

Luis Daniel Mora-Murillo¹, Felipe Orozco-Gutierrez², José Vega-Baudrit², Rodolfo Jesús González-Paz^2*

Journal of Renewable Materials, Vol.5, No.3-4, pp. 220-230, 2017, DOI:10.7569/JRM.2017.634112

Abstract Nowadays, green polyurethane (PU) foams are mostly synthesized by replacing an amount of petrochemical polyol with biobased polyol. Here we report five different families of isocyanate prepolymer formulations that were prepared with biobased sources and the correlation between the structure of chains and the properties of the produced PU foam. Foam behavior in tension, torsion, compression, shape memory tests and physical properties were studied by dynamic mechanical thermal analysis (DMTA); interactions in the polymer chains were analyzed by Fourier transform infrared spectroscopy (FTIR); and thermal analysis was performed by thermogravimetry (TGA) and differential scanning calorimetry More >

Róger Moya^*, Lucia Fallas-Valverde, Alexander Berrocal, Dawa Méndez-Álvarez

Journal of Renewable Materials, Vol.5, No.3-4, pp. 208-219, 2017, DOI:10.7569/JRM.2017.634111

Abstract This study evaluated the durability in terms of decay and mechanical resistance of thermally modified (TM) wood of Tectona grandis and Gmelina arborea treated at 160, 180, 200 and 220 °C. The TM wood of both species treated above 200 °C and 180 °C respectively presents lower weight loss (WL) after 300 days exposure in field and accelerated testing. It was also found that in field testing over 180 °C, the module of elasticity (MOE) and module of rupture (MOR) of the exposed and unexposed stakes of TM wood were not affected. Accelerated tests showed More >

Felipe Orozco^1‡, Brian Alfaro-González^1‡, Yendry Corrales Ureña¹, Karolina Villalobos¹, Angie Sanchez¹, Francisco Bravo¹, José Roberto Vega¹, Orlando Argüello-Miranda^1†*

Journal of Renewable Materials, Vol.5, No.3-4, pp. 199-207, 2017, DOI:10.7569/JRM.2017.634110

Abstract As an outcome of millions of years of evolution, biological systems have developed different methods to interact with their surroundings. Many of these adaptations, such as secretions, light-interacting surfaces, biochemical active compounds, and many other survival strategies, are phenomena occurring at the nanometric scale. In this review, we describe how extracellular nanometric structures are responsible for manipulating energy and matter, creating some of the emergent properties of life. Iridescent colors in birds’ feathers, the manipulation of wettability of insects’ exoskeletons, the adhesive properties of nanopatterned secretions and the ability to polarize light are examples of More >

Karolina Villalobos¹, Hider Rojas¹, Rodolfo González-Paz², Daniel Brenes Granados², Jeimmy González-Masís², José Vega Baudrit^1,3, Yendry Regina Corrales-Ureña^1*

Journal of Renewable Materials, Vol.5, No.3-4, pp. 189-198, 2017, DOI:10.7569/JRM.2017.634109

Abstract Because starch is a biodegradable polymer with low cost and wide availability it is an attractive material for producing edible films for fruits. Films produced with pure starch have the disadvantage of being fragile. To overcome this issue, propolis nanoparticles were used as a novel plasticizer. Mechanical, thermal and morphological properties of the films containing 0.5, 1 and 3 wt.% propolis nanoparticles were evaluated. The best performance was obtained using 0.5 wt.% propolis, increasing the Young’s modulus and decreasing the glass transition temperature (Tg), showing their plasticizing effect. The results of scanning electron microscopy (SEM) More >

Agnieszka Sobczak-Kupiec¹, Klaudia Pluta¹, Dagmara Malina^1*, Bożena Tyliszczak²

Journal of Renewable Materials, Vol.5, No.3-4, pp. 180-188, 2017, DOI:10.7569/JRM.2017.634106

Abstract In recent years, the development of composite biomaterials has been the subject of very intensive research. The elaboration of technology for manufacturing new biomaterials will allow their practical implementation and adaptation to changing market needs. One of the key components in the developed composite materials will be natural origin hydroxyapatite (HAp) and tricalcium phosphate (TCP) obtained from bone products. In this study, preparation and detailed characterization of bone-derived calcium phosphates as a component of biomaterial composites is proposed. This novel method of obtaining hydroxyapatite for biomedical applications allows the obtainment of a material with expected More >

Bożena Tyliszczak¹, Anna Drabczyk^2*, Sonia Kudłacik², Agnieszka Sobczak-Kupiec²

Journal of Renewable Materials, Vol.5, No.3-4, pp. 174-179, 2017, DOI:10.7569/JRM.2017.634107

Abstract In this study a series of hydrogels based on Beetosan® and containing natural substances, such as bee pollen and sage (Salvia officinalis), have been prepared. Beetosan is a type of chitosan that is obtained from the external skeletons of naturally occurring dead honeybees. In multistage chemical treatment, dead insect waste is converted into chitosan that is used in research as a hydrogel matrix. Prepared materials were synthesized using photopolymerization. Studies on the obtained hydrogels included determining their swelling ability and behavior in a simulated body fluid environment, as well as determining their chemical structure by More >

María Belén Colombo Migliorero, Valeria Palermo^*, Patricia Graciela Vázquez, Gustavo Pablo Romanelli

Journal of Renewable Materials, Vol.5, No.3-4, pp. 167-173, 2017, DOI:10.7569/JRM.2017.634108

Abstract The utilization and valorization of industrial waste is an effective strategy for environmental protection. Since the juice industry generates a huge amount of citrus waste, we studied the application of thermally treated orange peel in catalysis. On the other hand, Keggin heteropolyacids are excellent oxidant catalysts used as a replacement for conventional oxidants; however, their solubility in polar solvents and the low specific area limit their use as heterogeneous catalysts. The utilization of treated orange peel as heteropolyacid support for the selective oxidation of sulfides is presented here. Firstly, orange peel was thermally treated, and More >

Yendry Corrales, Bernal Sibaja, Rodolfo González, José Vega-Baudrit

Journal of Renewable Materials, Vol.5, No.3-4, pp. 165-165, 2017, DOI:10.7569/JRM.2017.634149

Abstract This article has no abstract. More >