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Polybutylene terephthalate (PBT) is a semi-crystalline engineering thermoplastic polyester. PBT offers rapid molding cycles, high heat resistant, crystallinity, fatigue resistance, strength and rigidity, excellent electrical properties, creep resistance, reproducible mold shrinkage and chemical resistance. In this study, PBT was loaded with synthetic graphite and carbon fiber at different weight fractions (10-40 wt.%). PBT-based composites were fabricated by the melt mixing process by using a co-rotating twin screw extruder then thermal, mechanical and morphological properties of filled PBT composites was investigated. Weight fraction of carbon fiber (up to 30 wt.%) increases the tensile strength and flexural strength of PBT, but synthetic graphite loading decreases the tensile strength and flexural strength of PBT. The highest in-plane and through-plane thermal conductivity values were obtained as 9.24 for 40 wt.% synthetic graphite filled composite and 3.41 W/mK for 40 wt.% carbon fiber reinforced composite, respectively. Carbon fiber was found to be more effective in increasing the through-plane thermal conductivities than synthetic graphite., Ege University Research Projects Coordination [18-MUH-027], The author(s) received funding from Ege University Research Projects Coordination (Project no: 18-MUH-027).

In this study, the performance of sandalwood (SW), as an efficient potential filler material for high-density polyethylene (HDPE), was investigated in detail. Firstly, the characterization of SW was conducted by the determination of chemical composition with chemical and thermal analysis methods. The distribution of SW particles, which were used in composite fabrication, was obtained by using a dynamic light scattering analyzer. Then, the composites of SW, whose weight fractions varied from 5% to 20%, with HDPE were produced in a high-speed thermokinetic mixer. The detailed characterization of composites was made by using thermogravimetric analysis, scanning electron microscopy, X-ray diffraction analysis, differential scanning calorimetry, dynamic mechanical analysis (DMA), Fourier transform infrared, thermal conductivity measurements, and tensile and three-point bending tests. From DMA, storage modulus and loss modulus values of the HDPE matrix increased with increasing the weight fraction of SW. It is clearly seen that SW incorporation into HDPE at weight fractions of 5% and 20% exhibited the best improvement in terms of tensile and flexural strengths, respectively. It can be noted that the reinforcement effect of SW for HDPE is more prominent at high temperatures.

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].

Polyamide 4.6 has excellent properties, such as high temperature resistance, crystallinity, fatigue resistance, melting temperature, excellent creep resistance, toughness, and good wear properties, but low thermal conductivity values. For this reason, its use in thermal applications has been limited. In this study, its use in thermal applications can be increased by increasing its thermal conductivity with carbon-based fillers and reinforcements added to the PA46 structure. The aim of this study is to examine the carbon fiber (CF), synthetic graphite (SG) and graphene nanoplatelet (G) loading on the mechanical, thermal, physical, and electrical properties of polyamide 4.6, which are produced using co- rotating twin-screw extrusion. Tensile and flexural strength of polyamide 4.6 increased with the addition of CF at all weight fractions. The highest electrical conductivity value was measured as 4.01 S/cm in PA46-20CF-20SG-3G composite material. The highest in-plane thermal conductivity achieved in this study at 20 wt% CF, 20 wt% synthetic graphite, and 5 wt% graphene loading was 20.43 W/mK. However, the highest through-plane thermal conductivity value was obtained to be 4.19 W/mK at 20 wt% CF. Graphene and synthetic graphite are more efficient to increase the in-plane thermal conductivity, while CF is more efficient to increase the through-plane thermal conductivity., scientific and technological research council of Turkey (TUBITAK) [117M088], The scientific and technological research council of Turkey (TUBITAK), Grant/Award Number: Project No: 117M088

In several studies, Isophorone diisocyanate (IPDI), a monomeric aliphatic diisocyanate, has been microencapsulated with various polymeric shells for self-healing purposes in polymer-based materials. In this study, for the first time, isophorone diisocyanate was microencapsulated with silica shell via interfacial polycondensation of a silica precursor (TEOS). The shell materials of the IPDI-loaded microcapsules reported in the literature are polymeric (organic). It is known from the literature that silica shell can chemically and physically bonded to cementitious matrices, allowing the microcapsules to remain stable for years without deterioration. Essential parameters such as the amounts of core material (IPDI), shell-forming material, and surfactant as well as the stirring speeds were investigated through yield, optical microscopy, SEM, TGA, and FTIR analyses. Promising results were obtained in the process of microencapsulation of isophorone diisocyanate with silica shell. The optimum core material/shell-forming material, oil phase/aqueous phase, and surfactant/oil ratios were found to be 1.0, 0.18, and 0.08, respectively.

Polypropylene is one of the commodity thermoplastics that is widely used in many different applications such as automotive, building, electric-electronics, textile, and packaging industries due to its properties and favorable cost-benefit ratio. The incorporation of mineral fillers such as mica, talc, wollastonite, and calcium carbonate into thermoplastics is a common practice in the plastics industry in order to reduce the production costs of molded products and enhance processibility, mechanical, and thermal properties. Mineral filled polypropylene composites provides high mechanical stiffness, thermal stability, and good dimensional stability over a wide temperature range. The filler weight ratio, type, size, and dimension have significant effect on mechanical, thermal, physical, and rheological properties of composites. Four different mineral fillers (talc, mica, calcite, and feldspar) at weight fractions of 40% were compounded with polypropylene by using a twin-screw extruder. Test specimens were obtained by injection molding process. The effect of various filler types on rheological and mechanical properties of polypropylene was investigated in this study. It was found that talc and mica loadings at 40 wt. % into polypropylene increased the flexural strength of polypropylene. The rheological properties of samples were more affected by the talc than calcium carbonate. © 2021 MIM Research Group. All rights reserved.

The 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.

It is known that polyphenylene sulfide (PPS), which is a semi-crystalline aromatic polymer, exhibits high thermal stability, outstanding chemical resistance, and excellent flame retardancy properties. However PPS has a poor electrical and thermal conductivity, which limits their uses in some applications where thermal conductivity is required for heat dissipation or storing efficiently. in order to improve thermal conductivity of Polyphenylene sulfide (PPS), PPS-Synthetic graphite (SG) composites were produced by using twin-screw extrusion. SG at different weight fractions (10, 30, 50%) were loaded into PPS and thermal conductivity values of composites were measured in plane and through plane directions. the effect of loading SG into PPS on the mechanical properties of PPS was determined by using three-point bending tests. Charpy tests were conducted to determine the impact properties of SG loaded PPS composites. the effect of SG loading on density of PPS was also determined. Differentials canning calorimetry analyses of SG loaded PPS composites were carried out to determine Cp values. When 50 wt% SG was loaded into PPS, in plane and through plane thermal conductivity of PPS were obtained to be 6.54 and 1.5 W/mK, respectively. Considering ISO 180 standard, charpy-notched impact strengths of PPS-10SG, PPS-30SG, and PPS-50SG are determined to be 9.69, 8.75, and 7.9 kJ/m2 respectively. From conducted result it was concluded that in spite of loading of SG, the mechanical properties of PPS has not affected greatly., Polymer Proc Soc, Sabanci Univ, TUBITAK "The Scientific and Technical Research Council of Turkey"Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [117M088], The authors would like to thank TUBITAK "The Scientific and Technical Research Council of Turkey" for financial support under Project Number 117M088.

The aim of this study is to demonstrate whether Carpinus betulus L. (CB) powder can be used as an alternative filler/reinforcement material for polypropylene (PP). About 5, 10, 15, and 20 wt% CB loaded PP composites were prepared by a high-speed thermokinetic mixer. In this article, the effects of weight fraction of CB within PP on thermal, viscoelastic, chemical, mechanical, crystallographic, and morphological properties of PP composites were investigated by tensile and three-point bending test, dynamic mechanic analysis, thermogravimetric analysis, differential scanning calorimetry, Fourier transform infrared analysis, and scanning electron microscopy. Melting temperature of the composites decreased with the increase of CB content. The crystallization temperature of PP increased with the addition of CB into PP. When 10 wt% CB filler was loaded into PP, the tensile of PP increased by about 29 wt%. The storage modulus of PP were remarkably enhanced with increasing CB weight fraction. About 5 wt% CB addition into PP increased the flexural strength of PP by about 32%.

The objective of this study is to understand the significance of graphene oxide type for the improvement of mechanical properties of carbon fiber reinforced epoxy composites. Modified epoxy systems were prepared by adding two different graphene oxide nanoparticles prepared by the modified Hummers method (GOH) and Laachachi method (GOL). in the second stage, carbon fiber reinforced epoxy composites were produced using prepreg manufacturing technique. X-ray Photoelectron Spectroscopy characterizations of the pure graphene and modified graphene nanoparticles (GOH and GOL) were performed to confirm the oxidation of the nanoparticles. the morphology of the nanocomposite epoxy resin was investigated with scanning electron microscopy. Mechanical tests were conducted with composites to determine the properties of the final materials. It was observed that the addition of the GOH improved the longitudinal tensile and flexural strength values by 41 and 33%, respectively. Interlaminar shear strength (ILSS) values of epoxy/carbon fiber significantly increased up to 58% with GOH addition. Moreover, the results show that nano-enhanced resins could be a key component for many composites, and it can be a suitable material for long term usage and resistance of sudden failure of composites., Ataturk UniversityAtaturk University [BAP 2011/395]; Ege University Scientific Research GrantEge University [BAP 11-MUH-083], The authors would like to acknowledge the financial support provided by Ataturk University Scientific Research Grant, BAP 2011/395 and Ege University Scientific Research Grant, BAP 11-MUH-083. Furthermore, the authors would like to thank Dr. Murat Alanyalioglu and Dr. Ferit Cakir for their scientific contributions.

Bu çalışmada silika-esaslı partiküller (SP), tetra etoksi silan (TEOS) kullanarak sol-jel yöntemi ile üretilmiştir. Üretilen silika-esaslı partiküller ile poliüretanın (PU) ısıl iletkenliğinin düşürülmesi amaçlanmıştır. Bu parçacıklar farklı oranlarda (ağırlıkça %0,5, 1, ve 2) poliüretanın içine ilave edilerek kompozit plakalar elde edilmiştir. Bu plakaların yapılan ısıl iletkenlik ölçümlerinde poliüretana %0,5 SP eklenmesi ile ısıl iletkenlik değerinin %16 civarında azaldığı görülmüştür. Bunun yanısıra basma dayanımında ise %6’lik bir azalma gerçekleşmiştir. Daha yüksek SP’nin PU’ya eklenmesiyle ısıl iletkenlikte azalma oranı düşerken basma dayanımındaki bozulma artmıştır. SP eklenmesi poliüretanın kimyasal yapısını, ısıl stabilitesini çok fazla değiştirmezken, ısıl genleşme katsayısını ise düşürmüştür. Poliüretan kompozitlerin içerisindeki SP parçacıkların dağılımı da taramalı elektron mikroskop analizleri ile incelenmiştir., In this study, silica-based particles (SP) were fabricated via sol-gel method by using tetraethoxy silane. It is aimed to reduce the thermal conductivity of polyurethane (PU) by means of silica-based particles. the composite plates were obtained by adding these particles into PU at various ratios (0,5, 1, 2 wt%). the measurements of thermal conductivity values of these plates showed that 0,5% SP addition into PU decreased the thermal conductivity by 16%. in addition, compression strength value of PU decreased by 6%. While addition of higher weight fractions of SP into PU reduced the decreasing rate of thermal conductivity, degradation in compressive strength values increased. SP addition into PU has not changed the chemical structure and thermal stability considerably, however thermal expansion coefficient decreased remarkably. the distribution of SP within the PU matrix was examined by scanning electron microscopy observations.

The aim of this study is to investigate the filling properties of an agricultural waste, olive pomace powder (OP), for polypropylene (PP) matrix material. Different weight fractions of OP (from 10 to 40 wt %), which has a median particle size of 21.36 mu m (D50) mu m, were loaded into PP by high-speed thermo kinetic mixer. In this research, the effects of weight fraction of OP within PP on mechanical, viscoelastic, thermal, chemical, crystallographic, and morphological properties of PP composites were investigated by tensile and three point bending test, dynamic mechanic analysis, thermogravimetric analysis and differential scanning calorimetry, Fourier transform infrared analysis, X-ray diffraction analysis, and scanning electron microscopy. When 40 wt% OP filler was loaded into PP, the Young's modulus and flexural modulus of PP increased by about 62.5% and 19%, respectively. The storage modulus and thermal stability of PP were remarkably enhanced with increasing OP weight fraction. (C) 2017 Elsevier Ltd. All rights reserved.

In-plane alignment of graphene nanoplatelets (GNPs) in thin thermal interface material layers suppresses the through-plane heat transport, which limits the performance of materials. In order to suppress the in-plane alignment of the GNP filler within polypropylene (PP) and increase the through-plane component, modification of GNP (MG) was performed in this study. For this aim, GNP was treated with diallyldimethylammonium chloride solution and filled with PP at different weight fractions by using a laboratory type high-speed thermo-kinetic mixer. The effect of MG loading into PP on thermal conductivity and surface resistivity of PP was measured. With using MG as a conductive filler for PP, instead of GNP, through-plane conductivity increased by 11%, however in-plane conductivity decreased by 33%. Modified GNP-filled PP showed better through-plane conductivity and surface resistivity than those of unmodified GNP-filled PP. Tensile and three point bending tests were performed to determine tensile and flexural properties of composites. Dynamic mechanical analysis was carried out to evaluate viscoelastic properties, such as storage modulus and loss modulus of composites. The thermal properties of samples were measured by using a differential scanning calorimetry, thermogravimetric analysis, and thermo-mechanical analysis. Scanning electron microscopy was utilized to observe the fracture surfaces of the composites after tensile tests. (C) 2018 Society of Plastics Engineers

EgeUn###, Pumice stone (P), which is as a cheap material, can be a good candidate for filling material for polymers because of its high thermal resistance. Its effect on properties of polypropylene (PP) has not been studied in detail up to now. The mechanical, viscoelastic, thermal, morphological, crystallographic, and thermomechanical behaviors of PP filled with P powder were studied. The composites were produced by adding different weight fractions of P powder (0-40 wt%) into PP using a high-speed thermo kinetic mixer and compression molding. The highest tensile and flexural strength values, 26.5 and 46.4 MPa, respectively, were obtained when 10 wt% of P powder was filled into PP. Besides, the storage and loss modulus of PP was increased with the addition of P powder. The onset decomposition temperature of PP increased by 39 degrees C with P powder loading into PP. The addition of P powder into PP led to a significant increase on the crystallinity of PP. It is interesting to report that thermal conductivity of PP was increased with increasing weight fraction of P powder.

Storing healing agents in capsules is one of the most promising self-healing methods in cementitious materials. Because of the considerable advantage of microencapsulation, it has become more interested as compared to the other encapsulation methods. The sodium silicate, which has many advantages as a healing agent in cementitious materials, can be encapsulated through the interfacial polymerization of shell-forming monomer on the aqueous sodium silicate droplets. This study, which is a part of comprehensive project, aimed to produce these microcapsules by optimization of the monomer. The microcapsules were characterized by the yield, SEM, EDS, FTIR, TGA, and XRD analyses. In addition, the fracture behavior of the optimized microcapsule was examined in a cement paste matrix. It was observed that most of the microcapsules seem to be spherical shaped and free-flowing powder. Fracture behavior of optimized microcapsules revealed a sufficient shell-matrix interfacial bond strength which is essential for releasing healing agent into cracks. (C) 2017 Elsevier Ltd. All rights reserved.

In this study, stirring speeds during the synthesizing process of the sodium silicate/polyurethane microcapsules were optimized. The yield values of microcapsules at different stirring rates were evaluated. Based on the yield values and shape of microcapsules, optimized microcapsules were obtained. The measurements of the shell thickness of microcapsules were performed on the fractured microcapsules by using scanning electron microscopy. The optimized microcapsules were further characterized by means of optical microscopy and nanoindentation. Load vs. displacement and modulus of elasticity vs. displacement characteristics of the microcapsules were obtained. The average modulus of elasticity was found to be 633 MPa. The self-healing efficiency of the optimized microcapsules was evaluated by means of compressive strength tests. The incorporation of microcapsules reduced the compressive strength of fiber-reinforced mortar by 12–22%. However, it was observed that the microcapsules enhanced the self-healing capacity (recovery in compressive strength) of the mortar.

In this study, we synthesized antistatic and ultraviolet-resistant acrylic films with a combination of ionic liquids and ZnO nanoparticles for the prevention of static electricity and ultraviolet instability. ZnO and two different ionic liquids such as 1-ethyl-2,3-dimethylimidazolium ethyl sulfate and methyl-tri-n-butylammonium methylsulfate were preferred to achieve conductive and ultraviolet-resistant acrylic films. To obtain the highest ultraviolet protection factor and the lowest surface resistivity for the acrylic film, the combined effect of ZnO nanoparticles and the ionic liquids was utilized. The surface resistivity, thermal conductivity and effusivity, thermogravimetric analysis, and ultraviolet resistivity of the films were investigated. Surface morphology of the films and distribution of ZnO were also observed by scanning electron microscopy. The acrylic polymer exhibits higher ultraviolet resistance and lower transmission even in the low content of ZnO nanoparticles as compared with the neat polymer. The film consisting of methyl-tri-n-butylammonium methylsulfate ionic liquid showed the highest electrical conductivity performance even after 150 days. Consequently, ZnO nanoparticles are determined to be influential on ultraviolet-resistant properties, whereas ionic liquids are efficient on electrical conductivity performance of the acrylic polymer.

8th International Advances in Applied Physics and Materials Science Congress and Exhibition (APMAS) -- APR 24-30, 2018 -- Fethiye, TURKEY, WOS: 000481717400048, The aim of this study is to investigate mechanical and thermal properties of linear low density polyethylene (LLDPE)-based composite prepared with different almond shells powder (AS) contents. In this paper, AS (5, 10, 20, 30, and 40 wt%) filled LLDPE composites were prepared by compounding polyethylene and AS using a co-rotating twin screw extruder. All specimens for mechanical tests were molded using injection molding. 40 wt% AS filling into LLDPE has led to 100% increase in flexural strength of LLDPE. AS filling into LLDPE decreased the MFI value of LLDPE. AS filling into LLDPE at low weight fractions (5 and 10%) has not affected the un-notched impact strength of LLDPE. Thermal properties of the composite were studied by thermal gravimetric analysis (TGA). From TGA analysis, it is seen that degradation of AS within LLDPE started at about 200 degrees C

8th International Advances in Applied Physics and Materials Science Congress and Exhibition (APMAS) -- APR 24-30, 2018 -- Fethiye, TURKEY, WOS: 000481717400051, The aim of this study is to investigate the effect of various filler materials such as talc, glass bead (GB), and bentonite on sound insulation efficiency of polypropylene (PP). In order to evaluate sound insulation properties of PP-based composites sound transmission loss (STL) was determined. Polypropylene based-composite granules were produced by using twin-screw extruder. Some test specimens were obtained by injection molding process. bentonite filled PP composite exhibited the highest STL values for 100, 200, 400, 500, and 800 Hz. While talc and bentonite loadings at 40 wt% into PP increased the flexural strength of PP, GB loading decreased the flexural strength of PP. Izod notched and unnotched impact strength of PP decreased by loading talc, bentonite, and GB into PP.

8th International Advances in Applied Physics and Materials Science Congress and Exhibition (APMAS) -- APR 24-30, 2018 -- Fethiye, TURKEY, WOS: 000481717400079, In this study it was aimed to improve the fire retardant performance of halogen free flame-retardant polypropylene by increasing limiting oxygen index value. Ammonium polyphosphate, pentaerythritol, and ulexite were used to improve flame retardancy of polypropylene. Ulexite powder filled (1, 2, and 4 wt%) polypropylene composites were obtained by using a twin-screw extruder and injection molding method. Thermal, mechanical, and flame retardant performances of polypropylene composites were investigated by several characterization techniques. Limiting oxygen index value was obtained higher than 45% when ulexite was added into polypropylene at 1-4 wt%. It was observed that flame retardant additives do not change the mechanical properties considerably. The effect of ulexite addition on melting and crystallization temperatures of polypropylene-based composite is not pronounced., Scientific and Technological Research Council of Turkey (TUBITAK)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [Teydeb 7160061], The authors would like to thank the Scientific and Technological Research Council of Turkey (TUBITAK) for financial support (Project No: Teydeb 7160061).

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].

Perlite is a glassy amorphous volcanic rock and generally used in construction industries. Possible uses of perlite powder in polymeric composites allow producing value-added products. In this study, expanded Turkish perlite (TP) powder was characterized by particle size distribution and Brunauer–Emmett–Teller analysis. TP-filled high-density polyethylene (HDPE) composites were manufactured via thermokinetic mixer by adding various weight fractions of TP powder (5, 10, 20, and 30 wt%) into HDPE matrix. Produced composites were characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, dynamic mechanic analysis, X-ray diffraction, and mechanical and thermal conductivity tests. From mechanical tests, it was observed that HDPE + 5% TP exhibited the greatest tensile strength. Flexural strength of the TP-filled HDPE composite was increased with the increasing TP content. Morphological properties of TP-filled HFPE composites were examined by scanning electron microscopy. As the weight fraction of TP was increased, storage modulus and loss modulus of the composites were increased. Moreover, the relaxation peak of HDPE was increased by the incorporation of TP into HDPE.

In this study, fumaric acid (FA) crosslinked carboxymethylcellulose (CMC) hydrogel (CMCF) based silver nanocomposites were coated on cotton fabric for antibacterial property for the first time. The performance of the nanocomposite treated cotton fabric was tested for different mixing times of hydrogel solution, padding times and concentrations of silver. The cotton fabrics treated with CMC hydrogel based silver nanocomposites demonstrated 99.9% reduction for both Staphylococcus aureus (Sa) and Klebsiella pneumonia (Kp). After one cycle washing processes of treated cotton fabric, there is no significant variation observed in antibacterial activity. From SEM and AFM analyses, silver particles in nano-size, homogenously distributed, were observed. The treated samples were also evaluated by tensile strength, thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR) analysis, fluid absorbency properties, and whiteness index. The treatment of cotton fabric with CMCF hydrogel did not affect the whiteness considerably, but increased the absorbency values of cotton. (C) 2015 Elsevier Ltd. All rights reserved.

In this study, a series of binary mixtures of Adipic acid (AA) and Sebacic acid (SA) at various mass fractions were prepared. A binary mixture of AA and SA in the ratio of 48.0:52.0 wt% was shown to be an eutectic mixture with melting temperature of 116 degrees C, melting latent heat of 206.0 J g(-1). In order to improve thermal properties of AA-SA eutectic mixture, multilayer graphite nanoplates (GNP) at different mass fractions (0.1, 0.3, and 0.5 wt%) was loaded into AA-SA mixture. The loading of 0.5 wt% GNP decreased the extent of supercooling from 17.7 to 3.6 degrees C. GNP loading did not change the thermal stability, functional groups and crystallographic properties of AA-SA eutectic mixture. Thermal conductivity of AA-SA was improved by GNP loading. Besides, morphological properties of GNP loaded AA-SA were examined by scanning electron microscopy observations. Thermal reliability of the AA-SA eutectic mixtures was investigated at different thermal cycles. Eutectic mixture of AA-SA containing GNP of 0.1 and 0.5 wt% showed relatively smaller variations in melting temperature and freezing temperatures. (C) 2015 Elsevier B.V. All rights reserved.

Fibers 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.

Summary In this study, arachidic acid (AA)/graphite nanoplate (GNP) composite material is proposed as a novel phase change material (PCM). In order to examine the influence of GNP loading into the base material (AA), composite PCMs were prepared with three different fractions (0.5, 1.0 and 2.0 in wt%). The thermal, chemical and morphological characteristics of the samples were introduced in terms of differential scanning calorimetry, thermogravimetric analysis, Fourier transform infrared, and X-ray diffraction analyses. Moreover, the thermal conductivity values of samples in the liquid state were measured by means of 3ω method. It was found that, for GNP fractions of 0.5, 1, and 2 wt. %, the thermal conductivity of composite PCMs have been increased by 15, 30 and 43% in comparison to the pure AA. Results also revealed that the GNP loading into the pure AA led to a reduction in the degree of subcooling and a small diminution in the latent heat values. Considering the thermal cycling tests, it was also obtained that the proposed composite PCMs remained stable even at the highest GNP loading. Conduction-dominated inward solidification process was simulated for one-dimensional spherical computational domain. For this particular case, it was found that the increments of 15, 30 and 45% in thermal conductivity tend to increase the effectiveness by 3.5, 6.4 and 8.7%, respectively. Copyright © 2015 John Wiley & Sons, Ltd.

PubMed: 29253989, 2-s2.0-85032709453, In order to analyze the bending mechanism of the electroactive? chitosan-based actuator, different amounts of poly(diallyldimethylammonium chloride) (PDAD) were incorporated in chitosan solution. The effects of PDAD concentration on electromechanical performance of chitosan actuator were investigated under various excitation voltages. With the incorporation of PDAD into chitosan solution, crosslinked chitosan film acts as an actuator showing a considerable displacement behavior. However it can be noted that higher incorporation of PDAD into chitosan solution decreased the performance of the actuators. Thermal, viscoelastic, and crystallographic properties of the chitosan films were examined by thermogravimetric analysis, dynamic mechanical analysis, and X-ray diffraction analysis, respectively. The effect of incorporation of PDAD in chitosan-based film on morphological properties of chitosan film was determined by scanning electron microscopy. It was observed that the films involving PDAD have larger pore size than the PDAD free film. © 2017 Elsevier Ltd, 111M643, This study was supported by TUBITAK-The Scientific and Technological Research Council of Turkey , with a Project Number: 111M643.

WOS: 000443173500003, In this study, paper processing residues containing a large extent cellulosic fibrous with inorganic filler such as calcite and clay minerals were used in the manufacturing of high density polyethylene (HDPE) composite. The residues ranging from 10 to 60wt% were loaded into HDPE in order to evaluate the effect of the paper processing residue filler on mechanical properties of HDPE. The composites were produced using mixing process by a high-speed thermo-kinetic mixer and molding process. Mechanical properties of the produced composites were analyzed using standard test methods. According to results, it was observed that the flexural modulus of composites increased with increasing filler contents. Especially, the flexural strength was increased by 26.3% for the 40wt% filler content The tensile strength of paper industry mill residues filled HDPE composites exhibited an increase of 10-20% compared to that of HDPE matrix. Consequently, in the present study, paper processing residues filler without any modifying agent was used for the production of HDPE composites having better mechanical properties compared to HDPE. Thus, paper processing residues which have no economic value and cause an environmental problem have served as a filler material for HDPE.

Flax fibers were modified by argon and air atmospheric pressure plasma treatments to improve the mechanical properties of flax fiber-reinforced unsaturated polyester composites. Plasma treatments were carried out at plasma powers of 100, 200, and 300 W. Both plasma surface treatments were conducted to improve the tensile strength, tensile modulus, flexural strength, flexural modulus, interlaminar shear strength (ILSS), Mode I interlaminar fracture toughness (GIC), and Mode II interlaminar fracture toughness (GIIC). Moreover, the maximum improvement in the mechanical properties was obtained after air plasma treatment of flax fiber at a plasma power of 300 W. Tensile strength, flexural strength, ILSS, GIC, and GIIC values of flax fiber-reinforced polyester composites increased by nearly 34%, 31%, 39%, 35%, and 42%, respectively. However, for argon plasma-treated flax fiber-reinforced polyester composites, the mechanical properties of composite increased up to argon plasma power of 200 W.

EgeUn###, Suppressing the through-plane component of the thermal conductivity caused by synthetic graphite (SG) alignment was decreased by loading of recycled carbon fiber (CF) into SG loaded polypropylene (PP) composites. The effect of CF loading into SG loaded PP composites on thermal stability, viscoelastic, and morphological properties were also investigated by thermogravimetric analysis, dynamic mechanical analysis, and scanning electron microscopy, respectively. CF loading into SG loaded PP composites increased through-plane conductivity considerably rather than in-plane conductivity. 20 wt% CF additions into 50 wt% SG increased through-plane and in-plane thermal conductivity values by 12.5 and 1.3 times, respectively. Storage and loss moduli of composites significantly increased with the increasing fiber weight content, particularly 20 wt%. Besides, while SG decreases the mechanical properties of PP, CF loading into SG loaded PP composites increased the mechanical properties., Research Foundation of Izmir Katip Celebi University [2016-GAP-MUMF-0030], The authors gratefully acknowledge the financial support given by the Research Foundation of Izmir Katip Celebi University (Project No: 2016-GAP-MUMF-0030).

In this study, flax fibers were treated by argon and air atmospheric pressure plasma systems under various plasma powers to improve interfacial adhesion between the flax fiber and high density polyethylene (HDPE) and unsaturated polyester. The interfacial adhesion of argon treated flax fiber for HDPE matrix is superior than those of air treated and untreated flax fiber. However for the adhesion between flax fiber and polyester matrix, air treatment is more efficient than argon treatment. Besides, greater plasma power causes greater interfacial adhesion, which was proved by pull out tests. The surface characteristics of flax fibers were examined using Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and Scanning electron microscopy (SEM), and roughness tests. X-ray photoelectron spectroscopy analysis (XPS) indicated that the air plasma-treated fiber had higher oxygen concentration and higher oxygen/carbon ratio than the untreated fiber and argon plasma treated fiber. Changes in the surface chemical composition and functional groups, and increases in surface roughness were obtained. After both plasma treatments, it was clearly seen that a new functional group (O-C=O) generates on the flax fiber surface. (c) 2012 Elsevier Ltd. All rights reserved.

The 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.

The aim of this study is to characterize linden fibres as a novel cellulose-based fibre to be used as a reinforcement material in composites and to investigate the adhesion property to unsaturated polyester. Up to now, there is no report regarding the potential usability of linden fibre in composite applications. Linden fibres were extracted from the stem of a plant of Tilia rubra DC. subsp. caucasica (Rupr.) V.Engl. Characterization of linden fibres was studied by Fourier transform infrared, X-ray photoelectron spectroscopy, thermogravimetric analysis, X-ray diffraction analysis, tensile and pull-out tests. Morphological properties of the fibres were observed through scanning electron and optical microscopes. Initial degradation temperature of the linden fibre was reported to be 238℃. The tensile strength and the Young’s modulus of the linden fibres were calculated to be 675.4 ± 45.7 MPa and 61.0 ± 9.8 GPa, respectively. The interfacial shear strength of the linden fibre with unsaturated polyester matrix was computed as 26.15 ± 2.27 MPa via pullout test. This study offers an alternative and eco-friendly reinforcement material which may have usability potential in polymeric composites.

This study aims to produce a long-term antistatic acrylic-based film by incorporating ionic liquid (IL), 1-ethyl-2,3-dimethylimidazolium ethyl sulphate (EIL) into acrylic resin. After loading, characterisations of samples were conducted by mechanically, thermally and morphologically. In order to determine antistatic properties, surface resistivity of samples was measured by using at different time intervals. The results indicated that IL loaded polymers showed a good antistatic property for a long time. The effect of incorporation on tensile strength, tensile modulus, flexural strength and flexural modulus of polymer were also obtained. After loading process, tensile strength, tensile modulus, flexural strength and flexural modulus values decreased considerably. The decrement in tensile strength of polymer is much less than that in flexural strength. The effect of EIL incorporation into acrylic resin on thermal conductivity and surface wettability was also investigated. From scanning electron microscopy images, EIL particles in nano-size range were observed in polymer structure.

Luffa cylindrica of Turkey's Aegean Region was evaluated in terms of fiber characterization and the mechanical properties of its composite with polyester. Characterization of Luffa cylindrica was carried out by Fourier transform infrared spectrophotometer, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy, and thermogravimetric analysis. Cellulose, hemicellulose, and lignin contents of Luffa cylindirica were also determined. Deconvolutions of XPS data enable determining the distributions of functional groups on the surface of Luffa cylindrica. Luffa cylindrica-reinforced polyester composite was subjected to water aging under a steam of sea-water containing 5% sodium chloride for 170 h at 50 degrees C. After water aging, tensile strength, flexural strength, interlaminar shear strength, and tensile elongation at break values of the composite decreased similar to 28%, 24%, 45%, and 31%, respectively. However, tensile modulus and flexural modulus did not change significantly. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci 123: 2330-2337, 2012

Parameters, such as pH, temperature, initial boron concentration, adsorbent dosage, and ionic strength, affecting boron adsorption onto chitosan beads were examined in this study. The following values were obtained as the optimum conditions in our studied ranges: pH 8.0, temperature = 308 K, amount of chitosan beads = 0.15 g, initial boron concentration = 4 mg L-1, and ionic strength = 0.1 M NaCl]. The adsorption kinetics were also examined in terms of three kinetic models: the pseudo-first-order, pseudo-second-order, and intraparticle diffusion models. The pseudo-second-order kinetic model showed very good agreement with the experimental data. Intraparticle plots seemed to have two steps and indicated multilinearity. Equilibrium data were evaluated with nonlinear and linear forms of the Langmuir and Freundlich equations. The experimental data conformed to the Freundlich equation on the basis of the formation of multilayer adsorption. To characterize the synthesized chitosan beads, we used Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM) analyses. As shown by FTIR analysis, the boron species may have interacted with the NH2 groups on chitosan. Microparticles of about 5 mu m appeared in the SEM micrographs of the chitosan beads. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci 122: 657-665, 2011

The effect of atmospheric air plasma treatment of jute fabrics on the mechanical properties of jute fabric reinforced polyester composites was investigated. The jute fabrics were subjected to different plasma powers (60, 90, and 120 W) for the exposure times of 1, 3, and 6 min. The effects of plasma powers and exposure times on interlaminar shear strength, tensile strength, and flexural strength of polyester based composites were evaluated. The greatest ILSS increase was about 171% at plasma power of 120 W and exposure time of 6 min. It is inferred that atmospheric air plasma treatment improves the interfacial adhesion between the jute fiber and polyester. This result was also confirmed by scanning electron microscopy observations of the fractured surfaces of the composites. The greatest tensile strength and flexural strength values were determined at 120 W for 1 min and at 60 W for 3 min, respectively. Moreover, it can be said that atmospheric air plasma treatment of jute fibers at longer exposure times (6 min) made a detrimental effect on tensile and flexural properties of jute-reinforced polyester composites. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci 121: 634-638, 2011

To increase the mechanical properties of recycled carbon fiber-reinforced polypropylene (PP) composites, recycled carbon fibers (RCF) were subjected to atmospheric plasma treatment at different plasma powers (100, 200, and 300W). The changes on surface topography and roughness of RCF were examined by atomic force microscopy. Plasma treatment of RCF increased the roughness value of RCF. The variation of surface elemental compositions and tensile strength of RCF were determined by using X-ray photoelectron spectroscopy and tensile test, respectively. Plasma-treated RCF-reinforced PP composites were fabricated using high speed thermo-kinetic mixer. Plasma treatment of RCF at 100W increased the tensile and flexural strength values of RCF-reinforced PP composites considerably by 17 and 11%, respectively. However, plasma treatment of RCF at higher plasma powers (200W and 300W) decreased tensile and flexural strength values of composites because of the etching of RCF. (c) 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47131.

This study intends to produce plasma polymer thin films of γ-glycidoxypropyltrimethoxysilane (γ-GPS) on glass fibers in order to improve interfacial adhesion of glass fiber-reinforced epoxy composites. A low frequency (LF) plasma generator was used for the plasma polymerization of γ-GPS on the surface of glass fibers at different plasma powers and exposure times. X-ray photoelectron spectroscopy (XPS) and SEM analyses of plasma polymerized glass fibers were conducted to obtain some information about surface properties of glass fibers. Interlaminar shear strength (ILSS) values and interfacial shear strength (IFSS) of composites reinforced with plasma polymerized glass fiber were evaluated. The ILSS and IFSS values of non-plasma polymerized glass fiber-reinforced epoxy composite were increased 110 and 53%, respectively, after plasma polymerization of γ-GPS at a plasma power of 60 W for 30 min. The improvement of interfacial adhesion was also confirmed by SEM observations of fractured surface of the composites.

Enhancement of the mechanical and vibrational properties of glass/polyester composites was aimed via matrix modification technique. To achieve this, unsaturated polyester was modified by incorporation of oligomeric siloxane in the concentration range of 1-3 wt%. Modified matrix composites reinforced with woven roving glass fabric were compared with untreated glass/polyester in terms of mechanical and interlaminar properties by conducting tensile, flexure, and short-beam shear tests. It was found that after incorporation of 3 % oligomeric siloxane into the polyester matrix, the tensile, flexural, and interlaminar shear strength (ILSS) values of the resulting composite increased by 16, 15, and 75 %, respectively. The increases in ILSS as well as in tensile and flexural properties were considered to be an indication of better fiber/matrix interaction as confirmed by SEM fractography images. Furthermore, the effect of oligomeric siloxane incorporation on the vibrational properties of the composites was investigated by experimental modal testing and the natural frequencies of the composites were found to increase with increasing siloxane concentration.

In this work, application of Luffa cylindrica in malachite green (MG) removal from aqueous solution was studied in a batch system. The effect of contact time, pH and temperature on removal of malachite green was also investigated. By the time pH was increased from 3 to 5, the amount of sorbed malachite green also increased. Beyond the pH value of 5, the amount of sorbed malachite green remains constant. The fits of equilibrium sorption data to Langmuir, Freundlich and Dubinin-Radushkevich equations were investigated. Langmuir isotherm exhibited best fit with the experimental data. Monolayer sorption capacity increased with the increasing of temperature. Sorption kinetic was evaluated by pseudo-first-order, pseudo-second-order. Elovich rate equations and intraparticle diffusion models. It was inferred that sorption follows pseudo-second-order kinetic model. Thermodynamic parameters for sorption process were also found out. Spontaneous and endothermic nature of sorption was obtained due to negative value of free energy (Delta G degrees) and positive value of enthalpy (Delta H degrees) changes. FTIR analyses were also conducted to confirm the sorption of malachite green onto L cylindrica. (C) 2010 Elsevier B.V. All rights reserved.

In this study, jute/polyester composites were fabricated. To improve the adhesion between jute fabric and polyester alkali-treated jute fabrics were treated with γ-methacryloxypropyltrimethoxysilane (γ-MPS). The effect of silane concentrations (0.1%, 0.3%, and 0.5%) on tensile properties, flexural properties, and interlaminar shear strength was investigated. Once jute fabrics were treated with 0.1% and 0.3% silane concentrations, the tensile properties of silane-treated jute polyester composites increased. However, when 0.5% γ-MPS was used in silane treatment, the tensile properties of jute/polyester composites decreased. 0.3% silane-treated jute/polyester composites exhibited superior improvements in terms of the flexure properties among the fabricated composites. Interlaminar shear strength measurements showed that best adhesion was provided by using 0.3% silane-treated jute/polyester composites. Good adhesion between silane-treated jute fabric and polyester was also confirmed by scanning electron microscope observations.

Pillared clay-based superabsorbents (PILC-SA) were synthesized by using Al pillared-montmorillonite K10 and KSF via graft copolymerization reaction of acrylic acid (AA). Swelling behavior of pillared clay-based superabsorbent films in distilled water and at different pH values were investigated at room temperature. It was also obtained that Al-KSF and Al-K10 based superabsorbents were pH dependent and showed a reversible swelling behavior. Water absorbency of Al-KSF based superabsorbent was higher than that of Al-K10 based one. SEM, FTIR, and XRD analysis were conducted for further characterization of the PILC-SA. FTIR analyses lead to ester formation between PILC and SA. XRD revealed the basal spacing of the pillared clays before and after in situ incorporation indicating that the morphology of the superabsorbent was exfoliated and the layers of clay dispersed on the composite.

In 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 Engineers

Chitosan-clay biocomposites have been prepared in which KSF-montmorillonite (KSF) is used as filler and diluted acetic acid is used as solvent for dissolving and dispersing chitosan and montmorillonite, respectively. The effect of KSF loadings in biocomposites has been investigated. The characterization with different methods (FTIR, DSC, TGA, SEM, and XRD) on chitosan/KSF biocomposites systems was examined. Morphology and properties of chitosan biocomposites have been studied compared with those of pure chitosan. The FTIR and SEM results indicated the formation of an intercalated-and-exfoliated structure at low KSF content and an intercalated-and-flocculated structure at high KSF content. The thermal stability and the mechanical properties of the composites were also examined by DSC, TGA/DTG, and tensile strength measurements, respectively. The dispersed clay improves the thermal stability of the matrix systematically with the increase of clay loading. Tensile strength of a chitosan film was enhanced until the clay ratio up to 2 wt% and elongation-at break decreased with addition of clay into the chitosan matrix. The XRD results confirmed the intercalation of the biopolymer in the clay interlayer by the decrease of 20 values while the chitosan-clay ratio increases. POLYM. COMPOS., 30:1035-1042, 2009. (C) 2008 Society of Plastics Engineers

The biosorption of a cationic dye, malachite green oxalate (MG) from aqueous solution onto an invasive marine alga Caulerpa racemosa var. cylindracea (CRC) was investigated at different temperatures (298,308 and 318 K). The dye adsorption onto CRC was confirmed by FTIR analysis. Equilibrium data were analyzed using Freundlich, Langmuir and Dubinin-Radushkevich (DR) equations. All of the isotherm parameters were calculated. The Freundlich model gave a better conformity than Langmuir equation. The mean free energy values (E) from DR isotherm were also estimated. In order to clarify the sorption kinetic, the fit of pseudo-first-order kinetic model, second-order kinetic model and intraparticle diffusion model were investigated. It was obtained that the biosorption process followed the pseudo-second-order rate kinetics. From thermodynamic studies the free energy changes were found to be -7.078, -9.848 and -10.864 kJ mol(-1) for 298, 308 and 318 K, respectively. This implied the spontaneous nature of biosorption and the type of adsorption as physisorption. Activation energy value for MG sorption (E-a) was found to be 37.14 kJ mol(-1). It could be also derived that this result supported physisorption as a type of adsorption. (c) 2008 Elsevier B.V. All rights reserved.