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In this study, almond shell waste (ASW) as filling material, pure (ER), and waste polystyrene modified bisphenol-A type epoxy resin (ER-PS) were used to obtain biobased composite materials. The modification of ASW was carried out with NaOH and linoleic acid (LnA). Fourier transform infrared spectroscopy (FT-IR), Scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and Particle size distribution analyses were used in the characterization of ASW. Composites were prepared at filling ratios of 10-20-30-40-50% by mass using the casting technique. The morphology of the composites was characterized by SEM. The effects of epoxy matrix type and BK filling ratio on composites' mechanical, thermal, and water sorption properties were investigated. Tensile strength and modulus of elasticity (e-modulus) values of ERPS/ASW composites were lower, and tensile elongation values were higher than ER/ASW composites. The highest tensile strength values of 95-129 MPa were obtained for LnA modified ASW composites. The order of the tensile strength of the prepared ER matrix composites according to the filler type is: linoleic acid-modified ASW (LnA-ASW)>NaOH treated ASW (NaOH-ASW) > unmodified ASW. The most suitable ASW ratio was found as 30% by mass. e-modulus values of all modified ASW composites were higher than the epoxy matrix. According to the hardness test results, there was no significant difference between the composites. The water sorption of the composites increased depending on the ASW ratio and had a weakening effect on the mechanical properties. [ABSTRACT FROM AUTHOR]

In this study, electroless nickel plating process was applied on dendritic copper powders obtained from scrap copper plate by electrolysis method. Morphological and oxidation studies of dendritic copper-nickel bimetallic powders obtained by electroless nickel plating processes for 30 min, 60 min and 90 min were carried out. While morphology studies were performed with scanning electron microscopy (SEM), oxidation resistance studies were performed with thermogravimetric analysis (TGA). According to the results obtained, the amount of reduced nickel on electrolytic copper particles increased with the increase of electroless nickel plating time. The reduced nickel layer is composed of nano-sized particles. With the increase of the electroless nickel plating time, the oxidation resistance values of the particles increased, while the oxidation starting temperatures were also increased. In addition, the layers and deposits formed by the nano nickel particles on the particle surfaces increased the surface area values of the electrolytic copper particles by about 20%. According to the results of the particle size analysis, it was determined that a coating layer up to 1 μ was obtained by increasing the average particle size values thanks to the electroless nickel plating layer. [ABSTRACT FROM AUTHOR]

In this study, UiO-66 doped PEI nanocomposite membranes were prepared for the purification of methylal/methanol binary mixtures by pervaporation process. Membranes were characterized by Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and, Thermogravimetric analysis (TGA). Pervaporation tests were performed at different operation temperature, feed methanol concentration, UiO-66 loading ratio and membrane thickness. The optimum operation conditions were determined as 30oC of operation temperature, 6 wt. % of feed methanol concentration, 0.5 wt. % doped PEI membrane and 50 µm of membrane thickness. Under these conditions, flux and methanol selectivity values were 1.48 kg/m2.h and 80126, respectively. The obtained results show that high purity methylal fuel bioadditive and green solvent can be acquired by pervaporation process. [ABSTRACT FROM AUTHOR]

Magnetite (Fe3O4), Humic Acid (HA) and Silver (Ag) are materials with important properties. Synthesizing a single material which will have all the properties of these materials can provide significant advantages for some application areas. In this study, synthesized Fe3O4@HA@Ag was doped into poly(vinyl pyrrolidone) (PVP), in weight ratios of 5%, 7.5% and 10%, and nanofiber production was carried out by electrospinning method. Structural properties of nanofiber structures were investigated by X-ray Diffraction (XRD), morphological properties by Scanning Electron Microscope (SEM), spectroscopic and thermal characterizations by Fourier transform infrared (FTIR) and Thermogravimetric Analysis (TGA). When the analysis results of nanofibers were evaluated, it was determined that Fe3O4@HA@Ag doped PVP nanofibers were successfully produced. [ABSTRACT FROM AUTHOR]

Poly (butylene terephthalate) (PBT) is one of the most used polyesters today; however, the attempts to convert PBT wastes into value-added products are still limited in the recycling context. One of the major drawbacks of the PBT recycling is thermal degradation during multiple melt processing cycles that leads to deterioration in molecular weight and properties of the polymer. In this study, recycled PBT (rPBT) was compounded with a polymeric chain extender (Joncryl ADR 4368) at different loadings (0.5, 1, 1.5 wt%) in a twin-screw extruder. The rheological, mechanical, and thermal properties of the samples were investigated using different characterization techniques. The rheological results showed that addition of chain extender improved the viscoelastic properties of rPBT due to recoupling of the broken chains. The profound effect of chain extender on upgrading properties of rPBT was also confirmed by tensile test results. The samples containing chain extender showed enhancement in elastic modulus and tensile strength, whereas the strain at break values decreased due to chain branching. The samples containing chain extender showed enhancement in elastic modulus and tensile strength, whereas the strain at break values decreased due to chain branching. The effect of chain extender on branched structure of the samples was also observed from the lower crystallinity values. Thermogravimetric analysis indicated that the chain extender increased thermal decomposition temperature of the PBT. The improvement in the properties of the samples containing chain extender became more significant with increase in chain extender concentration. [ABSTRACT FROM AUTHOR]

In this study, porous polymer composites that can be used as support materials in low temperature latent thermal energy storage applications were produced by emulsion templating method and the morphological, thermal and mechanical properties of the obtained materials were investigated. For this purpose, nanocellulose in the form of fibril was modified in order to make compatible with the emulsion system and used as a filler to improve the properties of porous polymeric foams obtained by polymerization of high internal phase emulsions. The morphological, thermal and mechanical properties of the obtained porous materials were investigated by Scanning Electron Microscopy (SEM), thermogravimetric analysis (TGA) and compression modulus measurements, respectively. In addition, the specific surface area values of the produced support materials were determined with the Brunauer-Emmet-Teller (BET) surface area and pore size analyzer. It has been observed that the addition of cellulose nanofibril filler in porous materials contributes positively to the pore morphology and thermal stability of the composite materials, while increasing the surface area values. The obtained composite materials were used as support materials in the production of shape-stabilized composite phase change materials (PCMs) containing n-pentadecane. As a result of thermal analyzes performed with Differential Scanning Calorimetry (DSC); it was found that composite PCM with a support matrix containing 0.75 wt(%) cellulose nanofibril filler has the highest n-pentadecane encapsulation ratio (61.12%) and the highest thermal energy storage capacity (122.0 J/g). [ABSTRACT FROM AUTHOR]

The aim of this study is to examine the behaviour of melon seed pyrolysis and to calculate its kinetic parameters along with thermodynamic properties. The thermogravimetric analysis experiments were conducted from ambient temperature to 800°C under nitrogen atmosphere at the heating rates of 5, 10, 20 and 40°C/min. It was determined that the pyrolysis process underwent through four stages where the second and third stages were the active pyrolysis stages. Kinetic calculations were carried out using modelfree Flynn-Wall-Ozawa, Kissinger-Akahira-Sunose, Starink and model-based Coats-Redfern methods. The apparent activation energy values of the second and third stages were calculated to be in the ranges of 123.9-215.5 and 141.9-234.2 kJ/mol, respectively. The Coats-Redfern method demonstrated that the second and third stages fit the reaction mechanisms of F1.65 and D5, respectively. Moreover, the enthalpy, entropy and Gibbs energy changes of the active pyrolysis stages performed at 10°C/min heating rate were determined using the results calculated from the model-free kinetic methods. The results obtained in the present study will be useful to provide necessary information needed for the design of melon seed pyrolysis processes. [ABSTRACT FROM AUTHOR]

Several methods are published for the coating of solid particles and liquid in recent years. The microencapsulation process is also included in these methods. Microencapsulation is a process by which droplets or particles of liquid or solid material are coated with a film of polymeric material. Microencapsulation technology is widely applied in pharmaceutical, food, agricultural pesticide, cosmetic, textile and other related fields. In this study, tocopherol (vitamin E) microcapsules were formed by complex coacervation method using gelatin and gum arabic polymer mixtures. To form the emulsion as a surfactant and the microcapsule wall to impart insolubility property as crosslinker was used. The effects of the parameters such as polymer ratio, surfactant quantity, cross-linker quantity on microencapsulation were investigated. Microcapsules morfology was characterized by scanning electron microscopy (SEM). Fourier transformation infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), high performance liquid chromotography (HPLC) analysis were carried out to explain the microcapsulation mechanism and investigate the microcapsule structure chemically. [ABSTRACT FROM AUTHOR]

In the present study, the synthesis, characterization, thermal and optical properties of poly(methyl methacrylate)(PMMA)/organomodified montmorillonit clay (OMTAB) nanocomposites were investigated. PMMA/nanoclay composites were synthesized by in situ polymerization method. Organomodified montmorillonit clay and PMMA/OMTAB nanocomposites were characterized by FTIR technique. The interlayer spacing of the organoclay platelets and the polymer clay nanocomposites were determined by X-ray diffraction spectroscopy. It was determined that the clay dispersion in the polymer matrix was exfoliated behavior. Thermal behaviors and thermal degradation activation energies of nanocomposites were determined by thermogravimetric analysis method (TGA). Polymer/nanocomposite thin films on the quartz surface were prepared by spin coating technique. The optical properties were obtained by measuring transmittance values in a UV-VIS spectrophotometer. [ABSTRACT FROM AUTHOR]