Improvement the thermal performance of Myristic acid

Paper presented to the 10th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Florida, 14-16 July 2014.This study mainly focus on two aspects; the first one is to increase the thermal conductivity of Myristic acid with graphene additives and the second one is to determine the influence of this increment on the melting duration of a particular encapsulated thermal energy storage system with PCM. As a result, thermal conductivity of composite myristic acid increased by 8%, 18% and 38% after graphene loadings of 0.5%, 1% and 2% into the pure MA, respectively. Besides, one-dimensional spherical computational domain has been considered, and the conduction dominated phase change process simulated with implementing temperature transformation method. Validity of the current code has been revealed by reproducing a numerical work in literature. For this particular case, it is found that the increments of 8%, 18% and 38% in thermal conductivity tend to reduce the total time of melting by 5.6%, 15% and 26%.dc201

Determination of properties of Althaea officinalis L. (Marshmallow) fibres as a potential plant fibre in polymeric composite materials

WOS: 000328801200024The mechanical, thermal, chemical, crystallographic and morphological properties of althaea fibres, extracted from Althaea officinalis L, was examined for the first time in this study. A. officinalis L. was obtained from Mordogan, Izmir (Turkey). After extraction process, lignin, cellulose and hemicellulose contents of althaea fibres were identified. Fourier transform infrared and X-ray photoelectron spectroscopy were utilized for surface functional groups of althaea fibres. By using X-ray diffraction analysis, CI value for althaea fibre is obtained to be 68%. The images of scanning electron microscopy were taken for observation of morphology of althaea fibres. The tensile modulus and tensile strength values of althaea fibre were obtained by single fibre tensile tests as 415.2 MPa and 65.4 GPa, respectively. Thermogravimetric analysis showed that thermal degradation of the fibre begins at approximately 220 degrees C. Besides, by pulling out the althea fibre from the embedded high density polyethylene, interfacial shear strength value was determined to be 8.16 MPa. The results suggest that the althaea fibre can be used in composite applications as a natural reinforcement material. (C) 2013 Elsevier Ltd. All rights reserved

Extraction and properties of Ferula communis (chakshir) fibers as novel reinforcement for composites materials

WOS: 000313854200062The aim of this study is to examine the use of Ferula communis fibers as potential reinforcement in polymer composites. The fibers are extracted from the F. communis plant which grows in Selcuk, Izmir in western Turkey. The chemical composition of ferula fibers in terms of cellulose, lignin, and ash contents was determined. Surface functional groups of ferula fibers were obtained by fourier transform infrared and Xray photoelectron spectroscopy. Crystallinity index and crystallite size were determined by X-ray diffraction analysis. The morphology of ferula fibers was investigated through scanning electron microscopy, the thermal behavior through thermogravimetric and differential scanning calorimetry analyses. The real density of ferula fibers was measured by means of Archimedes method with ethanol. The mechanical properties of F. communis were measured through single fiber tensile tests. The interfacial shear strength (IFSS) in a polyester matrix has been estimated from the pull-out test. Crown Copyright (C) 2012 Published by Elsevier Ltd. All rights reserved.Natural Science Foundation of Dokuz Eylul University under BAPDokuz Eylul University [2008145]The Authors sincerely acknowledge Natural Science Foundation of Dokuz Eylul University under BAP Grant No. 2008145 due to differential scanning calorimetry analysis. Also we thank Prof. Dr. Mithat Yuksel, Burhan SIMSIR and Selman Gulsen for their contributions to the study

Preparation and Properties of Rice Husk-Filled Plasticized Wheat Gluten Biocomposites

WOS: 000337668900001Rice husk (RH) reinforced wheat gluten/glycerol (Gly/Glut) and rice husk (R) reinforced wheat gluten-glycerol/chitosan-polyethylene glycol (Gly/Glut-CP) biocomposites with varying rice husk loading were prepared. Morphological, thermal, and mechanical properties of the biocomposites were investigated by scanning electron microscope, thermogravimetric analyzer, and tensile testing machine, respectively. Water absorption properties and surface functional groups of the biocomposite films were determined by weight measurement and attentuated total reflectance Fourier transform infrared spectroscopy, respectively. The results were discussed in terms of chitosan-polyethylene glycol (CP) and rice husk content. Although CP and 1-g rice husk addition decreased maximum degradation temperature of Gly/Glut film, adding of more rice husk did not considerably change the maximum degradation temperature. As a result of adding CP, the tensile strength of Gly/Glut film was increased by about 183%, whereas tensile modulus was decreased by about 34%. (C) 2013 Society of Plastics Engineer

Evaluating of Agave Americana Fibers for Biosorption of Dye from Aqueous Solution

WOS: 000350271200017Fibers extracted from Agave americana were evaluated as a low cost sorbent for the removal of Malachite Green (MG) from aqueous solution. Agave fiber was characterized by using X-ray diffraction (XRD), thermal gravimetric analysis (TGA), scanning electron microscopy (SEM), and determining chemical content such as cellulose and hemicellulose. The crystallinity index and average size of crystals of agave fibers were obtained to be 53.29 % and 1.4 nm, respectively. The effects of temperature, amount of sorbent and ionic strength on biosorption behavior were investigated. By using Langmuir, Freundlich, and Dubinin-Radushkevich equations, equilibrium biosorption data were analyzed. Based on R-2 values, the best fit was provided with Langmuir isotherm. The results showed that the largest biosorption capacity was obtained as 33 mg g(-1) at 318 K. According to the thermodynamic studies, biosorption was determined to be endothermic and spontaneous in nature. Biosorption kinetics was investigated by equations such as Elovich rate equations, intraparticle diffusion models, pseudo-second-order, and pseudo-first-order models.Simge SIVRIOGLU; Caner TETIKWe acknowledge to Simge SIVRIOGLU and Caner TETIK for their support to our study

Concentration Effect of gamma-Glycidoxypropyl-trimethoxysilane on the Mechanical Properties of Glass Fiber-Epoxy Composites

WOS: 000269341500008In this study, glass fibers. were modified using gamma-glycidoxypropyltrimethoxysilane of different concentrations to improve the interfacial adhesion at interfaces between fibers and matrix. Effects of gamma-glycidoxypropyltrimethoxysilane on mechanical properties and fracture behavior of glass fiber/epoxy composites were investigated experimentally. Mechanical properties of the composites have been investigated by tensile tests, short beam tests, and flexural tests. The short-beam method was used to measure the interlaminar shear strength (ILSS) of laminates. The tensile and flexural properties of composites were characterized by tensile and three-point bending tests, respectively. The fracture surfaces of the composites were observed with a scanning electron microscope. On comparing the results obtained for the different concentrations of silane solution, it was found that the 0.5% GPS silane treatment provided the best mechanical properties. The ILSS value of heat-cleaned glass fiber reinforced composite is enhanced by similar to 59% as a result of the glass fiber treatment with 0.5% gamma-GPS. Also, an improvement of about 37% in tensile strength, about 78% in flexural strength of the composite with the 0.5% gamma-GPS treatment of glass fibers was observed. POLYM. COMPOS., 30:1251-1257, 2009. (C) 2008 Society of Plastics EngineersResearch Foundation of Dokuz Eylul UniversityDokuz Eylul University [2007.KB.FEN.007]Contract grant sponsor: Research Foundation of Dokuz Eylul University; contract grant number: 2007.KB.FEN.007

Evaluating of reinforcing effect of Ceratonia Siliqua for polypropylene: Tensile, flexural and other properties

WOS: 000561350500014The aim of this study is to investigate the reinforcing effect of Ceratonia siliqua (CS) powder as a novel natural filler for polypropylene (PP) based composites. CS powder up to 20 wt% was filled into PP matrix by using high speed thermo kinetic mixer. Mechanical and thermal properties of CS filled PP based composites were investigated by tensile and three point bending test, dynamic mechanical analysis, thermogravimetric analysis, differential scanning calorimetry analysis, fourier transform infrared analysis, and thermomechanical analysis. Morphology of the composites was also investigated by scanning electron microscopy. By filling 5% and 10% of CS into PP, tensile strength and flexural strength of PP increased by about 32 and 23%, respectively. This indicates that CS has a great potential to be used as reinforcing filler for PP composites. CS filling into PP led to lower coefficient of thermal expansion values which could help preventing the thermal expansion

The effect of methyl-tri-n-butylammonium methylsulfate and graphite nanoplates on production of antistatic acrylic polymer

###EgeUn###Methyl-tri-n-butylammonium methylsulfate (BIL) was incorporated into acrylic resin to improve antistatic property of acrylic polymer (AP). In order to avoid reduction in the mechanical properties of acrylic film and to reach higher electrical conductivity values, the combination of graphite nanoplates (Gr) and BIL was used. The effects of incorporation of BIL and Gr into AP on UV-blocking properties and UV transmittance data of acrylic films were measured. After 120 days, AP containing 5 wt% BIL and 0.01 wt% Gr, and AP+15 wt% BIL exhibited antistatic property. While BIL incorporation into acrylic resin deteriorated the mechanical properties, 0.01 wt% Gr incorporation increased the tensile strength by 83%. [GRAPHICS] .Ministry of Science, Industry and Technology (Turkey)Ministry of Science, Industry & Technology - Turkey [0016.STZ.2013-1]This work was supported by the Ministry of Science, Industry and Technology (Turkey), [Project Number: 0016.STZ.2013-1]

Hybrid carbon filled thermoplastic composites: synergistic effect of synthetic graphite and graphene nanoplatelets on thermal and mechanical properties of polyamide 4.6

In comparison with conventional polyamides, polyamide 4.6 is known as one of the high-temperature polyamides due to polymer chain constituents which also enhances its dimensional stability, creep resistance, and chemical resistance. The effect of hybrid synthetic graphite and graphene nanoplatelets fillers on thermal conductivity of polyamide 4.6 based composites was investigated in this study. Synthetic graphite and graphene nanoplatelets filled polyamide 4.6 based composites were fabricated using a twin-screw extruder. The variations on electrical, mechanical, thermal, and morphological properties were also examined. The highest in-plane and through-plane thermal conductivity values were obtained for hybrid 40 wt.% synthetic graphite and 5 wt.% graphene nanoplatelets filled composites as 21.65 and 4.04 W/mK, respectively. It was reported that the usage of hybrid carbon fillers in polyamide 4.6 leads to better thermal conductivity value..Scientific and Technological Research Council of Turkey; Turkiye Bilimsel ve Teknolojik Arastirma Kurumu [117M088]The authors are grateful for the funding from the Scientific and Technological Research Council of Turkey; Turkiye Bilimsel ve Teknolojik Arastirma Kurumu [Project no: 117M088]

Variations of mechanical properties of jute/polyester composite aged in various media

Woven roving jute fiber-reinforced unsaturated polyester composites were subjected to water absorption tests in order to study the effects of water ageing on the mechanical properties. Composite specimens were immersed in distilled water and salt water up to 2736 h. The water absorption of specimens reached to an equilibrium level after an immersion time of 300 h. It was observed that tensile, flexural, and interlaminar shear strengths (ILSSs) of jute/polyester composites decreased depending on the immersion time. The ILSS values of the composites were reduced by more than 53% for both the distilled water and the salt water after an immersion time of 2736 h