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 >

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… 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 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 More >

Estefanía Lidón Sánchez-Safont¹, Jennifer González-Ausejo¹, José Gámez-Pérez¹, José María Lagarón², Luis Cabedo^1*

Journal of Renewable Materials, Vol.4, No.2, pp. 123-132, 2016, DOI:10.7569/JRM.2015.634127

Abstract Novel biodegradable composites based on poly(3-hydroxybutirate-co-3-hydroxyvalerate) (PHBV) and different contents of purifi ed alpha-cellulose fi bers (3, 10, 25 and 45%) were prepared by melt blending and characterized. The composites were characterized by scanning electron microscopy (SEM), wide-angle X-ray scattering (WAXS) experiments, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), dynamic mechanic analysis (DMA) and Shore D hardness measurements. Disintegrability under composting conditions was studied according to the ISO 20200 standard. Morphological results showed that high dispersion of the fi bers was achieved during mixing. Good adhesion on the fi ber-matrix interface was also detected by More >

Ryan Weisman³, Manoranjan Majji⁴, Kyle T. Alfriend⁵

CMES-Computer Modeling in Engineering & Sciences, Vol.111, No.3, pp. 269-304, 2016, DOI:10.3970/cmes.2016.111.269

Abstract This paper presents a closed form solution to Liouville's equation governing the evolution of the probability density function associated with the motion of a body in a central force field and subject to J2. It is shown that the application of transformation of variables formula for mapping uncertainties is equivalent to the method of characteristics for computing the time evolution of the probability density function that forms the solution of the Liouville's partial differential equation. The insights derived from the nature of the solution to Liouville's equation are used to reduce the dimensionality of uncertainties More >

Tamara Calvo-Correas¹, Mirna A. Mosiewicki², M. Angeles Corcuera¹, Arantxa Eceiza¹, Mirta I. Aranguren^2,*

Journal of Renewable Materials, Vol.3, No.1, pp. 3-13, 2015, DOI:10.7569/JRM.2014.634132

Abstract Rigid polyurethane foams were synthesized by using a vegetable oil-based polyol and 4,4-diphenylmethane diisocyanate prepolymer as the majority of reactives,. The polyol was produced by hydroxylation of crude linseed oil with performic acid generated in situ by the reaction of hydrogen peroxide and formic acid. The characterization by FTIR, H1 NMR, iodine and hydroxyl values of the polyol and its comparison with the original linseed oil supports the success of the reaction. The reference foam was subsequently modifi ed by substituting part of the linseed oil polyol with glycerol, diethylene glycol, and a polyethylene glycol More >

Pronob Gogoi, Dhaneswar Das, Shyamalima Sharma, Swapan K. Dolui^*

Journal of Renewable Materials, Vol.3, No.2, pp. 151-159, 2015, DOI:10.7569/JRM.2014.634129

Abstract Alkyd resins based on Jatropha curcas oil with different molar ratios of phthalic anhydride (PA) and maleic anhydride (MA) were prepared by alcoholysis followed by polyesterifi cation reaction. The progress of the reaction was traced by the determination of acid value at regular time intervals. From the kinetic study the extent of the reaction was found in the range of 52.4–61.2%. The prepared resins were blended with a commercially available fast-curing epoxy resin in order to improve the properties like curing time, chemical resistance, tensile strength, and thermal stability. The morphology study of the blends More >

K. M. Hess, W. V. Srubar III^*

Journal of Renewable Materials, Vol.3, No.3, pp. 175-182, 2015, DOI:10.7569/JRM.2015.634106

Abstract This article concerns the development and characterization of a protein-based alternative to traditional fiberreinforced polymer (FRP) composites used in construction. In this work, gelatin-based resins were prepared at various gelatin-to-water (g/w) ratios. The effects of g/w ratio and curing time on resin mechanical properties were investigated. Using gelatin resins with a 30% g/w ratio, (i) gelatin-flax and (ii) gelatin-fiberglass composites were fabricated, and their mechanical properties were characterized and compared to both (iii) epoxy-flax and (iv) epoxy-fiberglass composites. Fracture surface morphologies were investigated using scanning electron microscopy. Results indicate that gelatin-flax composites exhibit similar mechanical More >

William Eberts, Matthew T. Siniawski^*, Timothy Burdiak, Nick Polito

Journal of Renewable Materials, Vol.3, No.4, pp. 259-267, 2015, DOI:10.7569/JRM.2014.634137

Abstract Single-ply biocomposite laminates were fabricated with two different woven fabrics and a bio-based resin using a wet layup technique at room temperature. A highly elastic, stockinette weave bamboo fiber fabric and a thicker, inelastic plain weave bamboo fabric were both investigated. The elastic fabric was pre-strained at 25% intervals, ranging from 0–100% of its original length. Samples made with E-Glass and S-Glass, two common glass fiber reinforcements, were also fabricated using the bioresin as benchmarks. The ultimate strength and modulus of elasticity characteristics of the composites were determined using the ASTM D3039/ D3039M-08 standard test… More >