Puneet Kumar^1,*, J. Srinivas²

CMC-Computers, Materials & Continua, Vol.54, No.1, pp. 1-20, 2018, DOI:10.3970/cmc.2018.054.001

Abstract Evolution of computational modeling and simulation has given more emphasis on the research activities related to carbon nanotube (CNT) reinforced polymer composites recently. This paper presents the composite cylinder assemblage (CCA) approach based on continuum mechanics for investigating the elastic properties of a polymer resin reinforced by multi-walled carbon nanotubes (MWCNTs). A three-phase cylindrical representative volume element (RVE) model is employed based on CCA technique to elucidate the effects of inter layers, chirality, interspacing, volume fraction of MWCNT, interphase properties and temperature conditions on the elastic modulus of the composite. The interface region between CNT More >

A. Subba Rao^a,* , V. Ramachandra Prasad^a , P. Rajendra^a , M. Sasikala^a , O. Anwar Beg^b

Frontiers in Heat and Mass Transfer, Vol.9, pp. 1-9, 2017, DOI:10.5098/hmt.9.2

Abstract In this article, we investigate the nonlinear steady state boundary layer flow and heat transfer of an incompressible Jeffery non-Newtonian fluid from a permeable horizontal isothermal cylinder. The transformed conservation equations are solved numerically subject to physically appropriate boundary conditions using a versatile, implicit, finite-difference technique. The numerical code is validated with previous studies. The influence of a number of emerging non-dimensional parameters, namely with Deborah number (De), surface suction parameter (S), Prandtl number (Pr), ratio of relaxation to retardation times (λ) and dimensionless tangential coordinate (ξ) on velocity and temperature evolution in the boundary… More >

Elizabeth PÉREZ-TEJADA^1,4*, Juan MORALES-CORONA³, Luis Ernesto GÓMEZ-QUIRÓZ², María Concepción GUTIERREZ-RUIZ², Roberto OLAYO³

BIOCELL, Vol.41, No.2-3, pp. 41-44, 2017, DOI:10.32604/biocell.2017.41.041

Abstract Low pressure plasma polymer films were synthesized using pyrrole and allylamine monomers and adding iodine was used (or not) for the reaction in both cases. They were polymerized on glass substrates under the same reaction conditions. Polymerization of allylamine was also studied at different operating powers. These thin polymer films were used as culture surfaces for HepG2 cells, a cell line derived from a human hepatoma. The proliferation, differentiation and two-dimensional propagation until obtaining monolayer of the cells was studied on the different synthetized films and correlations were established between the conditions of synthesis, the More >

Shegufta Shetranjiwalla, Shaojun Li, Laziz Bouzidi, Suresh S. Narine^*

Journal of Renewable Materials, Vol.5, No.5, pp. 333-344, 2017, DOI:10.7569/JRM.2017.634102

Abstract The impact of polymerization protocol on phase structure and properties of entirely lipid-derived thermoplastic poly(ester urethane)s (TPEU)s was investigated. The TPEUs were synthesized from 1,7-heptamethylene diisocyanate, polyester diols and 1,9-nonanediol (ND) as chain extender. A two-stage polymerization method was used to prepare two TPEUs; one in which ND was added in the first stage of polymerization as part of the prepolymer and another in the second stage after the prepolymer was formed. Two very different morphologies exhibiting different degrees of phase separation were obtained, driven by the sequence of addition of the chain extender. The More >

Nicole Segura Salas¹, Felipe Orozco Gutiérrez³, Luis Daniel Mora Murillo², Yendry Corrales Ureña³, Shakira Johnson¹, José Vega Baudrit³, Rodolfo Jesús González-Paz^3*

Journal of Renewable Materials, Vol.5, No.3-4, pp. 313-322, 2017, DOI:10.7569/JRM.2017.634122

Abstract Vegetable oils are being used for the production of biodegradable polymers, opening new possibilities for the synthesis of greener materials that could compete in national markets with petroleum-based polymers. In this study, castor oil and a catalyst (cobalt[II] naphtenate as promotor and MEKP as initiator) from local stores and styrene in different ratios were used to produce thermostable polymers. The kinetics of the polymerization reaction was followed by infrared spectroscopy. A polymeric material was synthetized which presents good mechanical properties. Therefore, composites were produced using 1 wt% of microcellulose extracted from biomass waste as reinforcement 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 >

Elena Fortunati^1*, Francesca Luzi¹, Chiara Fanali², Laura Dugo², Maria Giovanna Belluomo², Luigi Torre¹, José Maria Kenny¹, Luca Santi³, Roberta Bernini³

Journal of Renewable Materials, Vol.5, No.2, pp. 81-95, 2017, DOI:10.7569/JRM.2016.634132

Abstract Hydroxytyrosol (HTyr), a biophenol found in extra-virgin olive oil or olive oil by-products, well known for its strong antioxidant activity, was used as active ingredient for poly(vinyl alcohol) (PVA) matrix to develop film formulations by solvent casting process. The effect of HTyr on the morphological, thermal stability, optical, mechanical and release properties of PVA were investigated, while water absorption capacity, migration with food stimulants, water vapor permeability and antioxidant properties were tested taking into account the final application as food packaging systems. Morphological investigations evidenced homogeneity of all PVA/HTyr films, while the presence of HTyr More >

Ananda S. Amarasekara^*, Muhammad A. Hasan, Eve Larkin

Journal of Renewable Materials, Vol.5, No.1, pp. 62-66, 2017, DOI:10.7569/JRM.2016.634129

Abstract Condensation polymerization of renewable resources-based monomers, 4-ketopimelic acid and glycerol, were studied using two different catalysts; p-toluenesulfonic acid and Sb2O3. The highest polymer yield of 96% was achieved by using a 3:4 mole ratio mixture of 4-ketopimelic acid and glycerol, with Sb2O3 (0.5 mol% relative to 4-ketopimelic acid) as catalyst and heating at 23–210 °C, under N2 for 1 h; then 210 °C, vacuum, 12 h. The poly(4-ketopimelic acid-glycerol) formed is insoluble in all common organic solvents and is shown to contain a branched polymeric structure with ketal and ester links by using FT-IR, 1H 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 >

Szczepan Bednarz^*, Angelika Wesołowska, Magdalena Trątnowiecka, Dariusz Bogdał

Journal of Renewable Materials, Vol.4, No.1, pp. 18-23, 2016, DOI:10.7569/JRM.2015.634131

Abstract New methods of preparation of crosslinked polymers from itaconic acid as a renewable monomer have been explored. Synthesis of hydrogels and xerogels from the acid in deep eutectic solvents (DESs) are described and some basic properties of the materials are reported. Most importantly, a surfactant-free method of creation of macroporous poly(itaconic-co-bisacrylamide) by phase separation polymerization in binary mixture of the DES and poly(ethylene glycol) is demonstrated. More >