Browsing by Author "Körpinar, B"

Now showing 1 - 6 of 6
  • No Thumbnail Available
    Item
    A new thiol-based oxidized polyethylene adsorbent for heavy metal ions removal from aqueous solutions
    Körpinar, B; Akat, H
    In the present study, it has been synthesized a new polymer, OXPESH (oxidized polyethylene functionalized with thiol groups), based on commercially used OXPE (oxidized polyethylene) for possible uses in the removal of heavy metals. Thiol-based oxidized polyethylene was successfully obtained by the esterification process. The synthesized polymeric material was employed as a possible adsorbent for the removal of heavy metal ions from aqueous solutions. Different techniques (H-1-NMR, FTIR, ICP-MS, (Elemental Analysis), XPS, SEM-EDX, TGA/DTG) were used to characterize the physical and chemical properties of the obtained adsorbent. it was observed that the optimum pH values for the adsorption capacity and removal efficiency of heavy metal ions were 6-8. It was observed that the adsorbent removed the best Ag+ > Cr3 + > Pb2+ > Al3+ > Cd2+ > Ni2+ > Cu2+ from the aqueous solution. As a result, thiol-based oxidized polyethylene has been demonstrated to be an effective sorbent for the removal of heavy metal ions from aqueous solution, indicating its potential relation with water improvement.
  • No Thumbnail Available
    Item
    Styrene-based unsaturated polyester-tungsten(VI) oxide composites: Preparation and investigation of their radiation shielding and thermal properties
    Körpinar, B; Öztürk, BC; Çam, NF; Akat, H
    In this study, the thermal and radiation shielding properties of composites obtained using different ratios of tungsten(VI) oxide unsaturated polyester were investigated. Composites were prepared using WO3.2H(2)O powder in different ratios (10%, 20%, 30%, 40%, and 50%.), and based on Styrene unsaturated polyester were used as resins. The linear attenuation coefficients of the composites were measured by the NaI(Tl) gamma spectrometry system. The attenuation coefficients were also calculated theoretically by the XCOM platform, taking into consideration the basic analysis of composites, and compared with empirical outcomes. According to the results of XRD and particle size distribution of WO3.2H(2)O powder demonstrated had obvious diffraction peaks and its pore size distribution values were good. When the thermal degradation curves of the composites are examined, it is seen that the remaining ash amounts of the prepared composites and the % mass of the prepared composites overlap. It was clear that the best shielding material in the studied composites was styrene-based unsaturated polyester +50% WO3.2H(2)O with a higher linear attenuation coefficient.
  • No Thumbnail Available
    Item
    Development of nanocomposites comprising starch and bismuth (III) oxide: An exploration of their viability as substitute materials for shielding high-energy radiation
    Körpinar, B; Akat, H; Cam, NF; Öztürk, BC
    This research focused on investigating the radiation shielding and thermal characteristics of composite materials created by varying the ratios of Bi2O3 and starch. Various composite formulations were developed by blending Bi2O3 powder with starch in ratios of 5%, 10%, 15%, 20%, 25%, 30%, 40%, and 50%. Linear attenuation coefficients of these composites were valued using a NaI(Tl) gamma spectrometry system. Additionally, theoretical calculations were performed using the XCOM platform and GAMOS simulation, incorporating fundamental composite analysis, and these results were compared with empirical data. X-ray diffraction analysis revealed distinct diffraction peaks in Bi2O3 powder, and its pore size distribution exhibited favorable characteristics. Considering the morphological properties of the nanocomposites, it was observed that Bi2O3 in the starch matrix did not undergo agglomeration and even formed homogeneous structures. Examination of the thermal degradation profiles of the samples indicated a significant overlap between the remaining ash quantities and the mass percentages of the prepared samples. The measured experimental linear attenuation coefficient results were ranged from 0.147 +/- 0.023 cm(-1) to 0.267 +/- 0.107 cm(-1) for 662 keV, from 0.119 +/- 0.007 cm(-1) to 0.165 +/- 0.021 cm(-1) for 1173 keV, and from 0.111 +/- 0.015 cm(-1) to 0.152 +/- 0.040 cm(-1) for 1332 keV for starch-Bi2O3 nanocomposites. Notably, the most effective shielding material among the studied samples was found to be a combination of starch and 50% Bi2O3.
  • No Thumbnail Available
    Item
    Novel starch-tungsten (VI) oxide biocomposites: Preparation, characterization, and comparisons between experimental and theoretical photon attenuation coefficients
    Körpinar, B; Öztürk, BC; Çam, NF; Akat, H
    This study synthesized biocomposites containing starch and WO3 at varying ratios of 10 %, 20 %, 30 %, 40 %, and 50 % and assessed their thermal and radiation-shielding properties. These biocomposites were characterized using Fourier-transform infrared spectroscopy, X-ray diffraction (XRD) analysis, particle-size distribution assessments, scanning electron microscopy-energy dispersive X-ray spectroscopy, and thermogravimetric analysis-differential thermogravimetry measurements. Furthermore, the linear attenuation coefficients of the biocomposites were experimentally measured using an NaI(Tl) gamma spectrometry system and theoretically computed using XCOM and GAMOS simulations for comparisons. The XRD and particle-size distribution profiles of the WO3.2H2O powder, respectively, demonstrated evident diffraction peaks and favorable pore-size distributions. Morphological characterizations revealed that the WO3 particles were homogeneously dispersed throughout the starch matrix without any agglomeration. Comparisons of the thermal degradation rates revealed that the pure starch and starch +50%WO3 biocomposite began decomposing at approximately 200 degrees Cand 300 degrees C, respectively, indicating that increasing WO3 proportions enhanced thermal stability. Furthermore, the starch +50%WO3 biocomposite demonstrated the highest experimental linear attenuation coefficient, with a value of 0.2510 +/- 0.0848 cm-1 at a gamma energy of 662 keV. Meanwhile, XCOM and GAMOS simulations revealed theoretical attenuation coefficients of 0.1229 and 0.1213 cm-1 for pure starch and 0.2202 cm-1 and 0.2178 cm-1 for the starch +50%WO3 biocomposite at 662 keV, respectively.
  • No Thumbnail Available
    Item
    Thiol-ended polycaprolactone: Synthesis, preparation and use in Pb(II) and Cd(II) removal from water samples
    Körpinar, B; Yayayürük, AE; Yayayürük, O; Akat, H
    In the present study, thiol-ended polycaprolactone (TPCL) was successfully prepared by ring opening polymerization using 2-3 dimercaptopropanol and caprolactone. The synthesized material was employed as a possible adsorbent for removal of Cd(II) and Pb(II) ions from water samples and the influence of essential parameters (pH of 5.0, adsorbent dosage of 10.0 mg and contact time of 30.0 min) on the adsorption process was studied. Different techniques (BET NMR, FTIR, zeta potential, TGA/DTG) were used to characterize physical and chemical properties of the polymer. Various isotherm and kinetic models were employed to understand plausible mechanisms involved in the adsorption. It is revealed that adsorption process fitted very well with the Langmuir isotherm and pseudo-second-order kinetic models for both of the ions. The adsorption capacity decreased slightly (< 10%), demonstrating the thiol-ended polycaprolactone performance even after four consecutive adsorption-desorption cycles. The spike recovery studies with real water samples yielded recoveries of over 90% which indicated the applicability of the method. As a result, thiol-ended polycaprolactone has been demonstrated to be effective sorbent for the removal of Cd(II) and Pb(II) ions from aqueous solution, indicating its potential relevance in water remediation.
  • No Thumbnail Available
    Item
    Poly(2-ethyl hexyl acrylate-co-methyl allyl polyethylene glycols ether-co-acrylic acid) pressure-sensitive adhesives: synthesis, characterization, investigations of adhesive and thermal properties
    Körpinar, B; Çay, EA; Akat, H
    In the present study, solvent-based acrylic copolymers were successfully synthesized by solution polymerization using methyl allyl polyethylene glycols ether, acrylic acid, and 2-ethyl hexyl acrylate for the fabrication of high-performance pressure-sensitive adhesive tapes. Different techniques (NMR, FTIR, TGA/DTG, Contact Angles, PSAs Test) were used to characterize the physical and thermal properties of the copolymers. The obtained copolymers were investigated as a possible adhesive for permanent or removable applications such as security labels for power equipment, foil tape for HVAC ductwork, automotive interior trim assembly, and sound/vibration dampening films. When the contact angles of the synthesized copolymers were examined, it was observed that while the amount of acrylic acid in the copolymer content was constant, the contact angle increased with the increase in the percentage of HPEG. In addition, while the amount of HPEG was constant in the copolymers, it was observed that the contact angle decreased with the increase in the percentage of acrylic acid. As a result, it was determined that the obtained copolymers showed hydrophilic character and wetted the contact surface. When the thermal properties of the copolymers were examined, while the acrylic acid ratio was constant, the thermal stability increased with increasing HPEG amount. While the HPEG ratio is constant in the copolymer content, the decrease in thermal stability with increasing acrylic acid is thought to be due to decarboxylation. Also, 7% reduction in DTG curves is evidence of decarboxylation of copolymers. According to the results of the pressure-sensitive adhesive test, it was observed that the surface wetting degree of the copolymers changed in direct proportion to the amount of acrylic acid increased and inversely proportional to the amount of HPEG, and the potential of the adhesives obtained in addition to being high-performance pressure sensitive adhesive tapes.