Profile Picture

Email Address

Birth Date

Research Projects

Organizational Units

Job Title


Last Name


First Name



Search Results

Now showing 1 - 10 of 46
  • Publication
    Organoclay Applications In Polymer Nanocomposite Filament Production
    (2011) Önder Karaoğlu, Emel; Ersoy, Mehmet Sabri; SARIER, NİHAL; 10598; 114920; 11772
  • Publication
    The Modification Of Na-Montmorillonite By Salts Of Fatty Acids: An Easy İntercalation Process
    (Elsevier Science Bv, Po Box 211, 1000 Ae Amsterdam, Netherlands, 2010-11-20) Önder, Emel; Ersoy, Sabri; SARIER, NİHAL; TR114920; TR10598; TR11772
    The organic modification of Na-montmorillonite (Na-MMT) clay by a reaction with the sodium salts of octadecanoic acid (SOD) and dodecanoic acid (SDD) was studied for the production of effectively intercalated and organophilic clays. The results of X-ray diffractometer (XRD) analysis reveal that the interlayer spacing of Na-MMT increased from 1.38 nm to 3.37-1.4-4 nm, 3.56-1.45 nm, 3.61-1.44 nm and 3.56-1.44 nm in the organoclays containing 393 mM SOD, 787 mM of SOD, 540 mM SDD and 1080 mM SOD, respectively. In the Fourier transform infrared spectrometer (FTIR) analyses, the stretching and bending vibrations of the hydroxyl groups of Na-MMT at 3619,3407 and 1634 cm(-1) 15 as well as the Si-O and Al-O vibrations of silica-alumina layers at 1039-534 cm(-1) 16 respond to the structural changes from hydrophilic to hydrophobic character. Thermogravimetric (TG) analyses results also suggest that the intercalation of SOD and SDD were achieved in the organoclays samples and the samples had permanent structural modifications, although they retained their inorganic character. The TEM-EDS and SEM results show that the SOD and SDD were well dispersed and intercalated throughout the interlayer spaces or adsorbed onto the clay surface. The suggested organic modification of Na-MMT is an easily applicable process in which the chemically stable, low cost and widely available SOD and SDD are used as intercalating agents. (C) 2010 Elsevier B.V. All rights reserved.
  • Publication
    Production of Dynamic Thermal Insulators By Coaxial Electrospinning of PAN and PEG
    (2015) Boz, Ezgi Ceren; Önder Karaoğlu, Emel; SARIER, NİHAL; ARAT, REFİK; 114920; 10598
    In the present work, we produced bicomponent nanofibers, composed of polyacrylonitrile (PAN) shells and PEG cores (PEG2000 and PEG4000), by co-axial electrospinning as new thermal energy storage materials that are suitable for further industrial uses. SEM images showed that the nanowebs of PAN-PEG shell-core nanofibers with smooth surfaces and of the average diameters smaller than 460 nm were successfully produced. The heat absorbed by PAN-PEG2000 nanoweb is 100.3 J/g between 50.6-56.5 C and of PAN-PEG4000 is 144.6 J/g between 54.0-60.7 C, which are quite remarkable in terms of their contribution to the dynamic thermal management of various textile products.
  • Publication
    Silver Nanoparticle Incorporated Thermocapsules Suitable For The Development of Thermally Enhanced Fabrics
    (2018) Önder Karaoğlu, Emel; Nergis, Fatma Banu; SARIER, NİHAL; ARAT, REFİK; 10598; 3551; 114920
  • Publication
    The mechanism of β- Carotene adsorption on activated montmorillonite
    (Springer-Verlag, 1989-07) Güler, Çetin; SARIER, NİHAL; 114920
    The variations in the structure of mineral during adsorption have been examined comparing the results of X-ray diffraction (XRD), differential thermal analysis (DTA), thermogravimetry (TG) and infrared (IR) spectroscopy of the acid activated montmorillonite clay mineral before and after adsorption of β-carotene. Based on the results, it was concluded that β-carotene attaches to the clay surface in the form of carbonium ions either by forming hydrogen bonds with Brönsted sites or by forming coordination bonds with Lewis sites of the activated clay mineral.
  • Publication
    Kinetics of the thermal dehydration of acid-activated montmorillonite by the rising temperature technique
    (1990) Güler, Çetin; SARIER, NİHAL; 114920
    The activation energies of dehydration and combustion of organic materials in a clay sample, and of dehydration of natural and acid-activated montmorillonite have been determined using a rising temperature programme technique. The effect of acid activation of the montmorillonite on the dehydroxylation is discussed.
  • Publication
    Development of Textile Nanocomposites With Thermal Energy Storage Capability
    (Natl Inst Science Communication-Niscair, 2021) Önder, Emel; SARIER, NİHAL
    In this study, textile-based composites with dynamic heat storage capability have been designed and developed, in addition to their existing passive insulation capacity. First, poly(acrylonitrile) (PAN) shell and poly(ethylene glycol) (PEG1000 or PEG1500) cores are produced by coaxial electrospinning. Then, these are incorporated into felt based composite structures, which demonstrate enhanced thermal properties as well as buffering function against temperature changes in the environment. The thermal energy absorption and release capacities of the felt composites including PANPEG1000 or PAN-PEG1500 nanowebs are measured as high as 81 Jg(-1) between 33 degrees C and 46 degrees C, and 48 Jg(-1) between 46 degrees C and 54 degrees C respectively. Felt composites, combined with PAN-PEG nanowebs offer forthcoming production applications in the field of dynamic thermal management in various industries.
  • Publication
    Synthesis and Electrospinning of Polyethylene Glycol Grafted Polyacrylonitrile Copolymers as Novel Solid-Solid Phase Change Materials
    (2016) Önder Karaoğlu, Emel; Boz Noyan, Ezgi Ceren; Menceloğlu, Yusuf Ziya; SARIER, NİHAL; ARAT, REFİK; 114920; 10598; 3329
  • Publication
    Synthesis of Biobased Oleocarbonates and Their Use in the Production of Thermally Enhanced Nanofibers by Electrospinning
    (2015) Boz, Ezgi Ceren; Önder Karaoğlu, Emel; SARIER, NİHAL; ARAT, REFİK; 114920; 10598
    Thermal management named as the dynamic heat-storage, has attracted more attention in the last decade because of the demand for developed energy conservation as well as improved thermal comfort. Phase change materials (PCMs), as thermally active materials, have a buffering effect against temperature changes. A PCM is capable of absorbing or releasing large amount of heat during phase transitions between two solid states and/or liquid and solid states. Various encapsulating and shape stabilizing methods for PCMs have been developed by researchers and industry prior to their application on the surfaces for reducing their reactivity with the outside environment, decreasing the evaporation and diffusion rates and promoting the ease of handling [1]. Fatty acids, fatty alcohols and their derivatives, obtained from fats and oils, serve as an important raw material for the oleochemical industry, since they are from biomass resources. Recently, fatty acids and their derivatives have attracted attention as potential biobased PCM candidates in consequence of their attractive thermal characteristics [2,3]. With the aim of spreading out the biobased PCMs away from fatty acids and fatty acid derivatives, this study concerns with the synthesis of two oleocarbonates, namely dihexadecyl carbonate and dioctadecyl carbonate, from fatty alcohols through a carbonate interchange reaction, and examines for their potential to be used as potential biobased PCM in dynamic thermal management of various composites such as clothing textiles and building envelopes. In the second part of the study, bicomponent nanofibers of those oleocarbonates have been produced using poly olefins as shell and oleocarbonates as core material by the coaxial electrospinning process. The thermal behaviors of dihexadecyl and dioctadecyl carbonates during heating and successive cooling in DSC analysis are given in Figure 1. The heat capacity of dihexadecyl carbonate was 192.8 Jg-1 between 33.9–47.8 C and of dioctadecyl carbonate was 178.2 Jg-1 at 47.4–51.1 C which were quite remarkable in terms of their contribution to the dynamic thermal management of PCM incorporated products. Electrospun nanofibers, carrying the thermal properties of corresponding oleocarbonate, were highly competitive with other existing strategies of encapsulating and shape-stabilizing PCMs.
  • Publication
    Ultrasound Sonication of Tokat Reşadiye Montmorillonite and its Feasibility in Nano Clay Production
    (2010) Önder Karaoğlu, Emel; SARIER, NİHAL; 114920; 10598