Sürdürülebilir Kalkınma Amaçları

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• MakaleAçık Erişim2026Scopus SJRQ2/r/munzur/1294
  Multifunctional PLA/PHA-Based films incorporating Moluccella spinosa extract for sustainable and antimicrobial food packaging applications

  Selcuk Pekdemir, Sibel; Gurler, Nedim; Yilmaz Sancar, Pelin; Karagulle, Burcu; Kok, Mediha; Pekdemir, Mustafa Ersin; Qader, Ibrahim Nazem

  In this study, a novel plant-based shape memory biocomposite was developed for sustainable food packaging applications. A poly(lactic acid)/poly(hydroxyalkanoate) (PLA/PHA) blend was reinforced with the ethanolic extract of Moluccella spinosa, a plant recognized for its bioactive constituents. Structural and thermal analyses confirmed the successful incorporation of the extract without compromising the polymer matrix integrity. The results demonstrated improved barrier performance, characterized by lower water vapor permeability, reduced moisture content, and slightly increased opacity with increasing concentrations of M. spinosa extract. In addition, the composite films exhibited enhanced shape memory behavior, which became more pronounced at higher extract concentrations. Antimicrobial assays revealed a limited and selective inhibitory effect, primarily against Gram-positive bacteria (Enterococcus faecalis and Clostridium perfringens), while no notable activity was observed against Escherichia coli and Staphylococcus aureus. These findings indicate a preliminary antimicrobial potential, likely associated with a sustained-release mechanism rather than strong bactericidal activity. Overall, the integration of M. spinosa extract into the PLA/PHA matrix offers a promising route to design multifunctional, biodegradable packaging materials with shape memory capability, where antimicrobial functionality serves as a complementary feature, contributing to the advancement of environmentally friendly and active food packaging technologies.

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• MakaleAçık Erişim2022Scopus SJRQ2/r/munzur/2683
  Biocompatible PLA/PCL blends nanocomposites doped with nanographite: Physico-chemical, and thermal behaviour

  Qader, Ibrahim Nazem; Pekdemir, Mustafa Ersin; Coşkun, Meltem; Kanca, Muhammed Sait; Kök, Mediha; Dağdelen, Fethi

  There is a great interest in nano-graphite due to its wide application in nanotechnology and important physical properties. Nanocomposites based on polymers and blends are important in the development of traditional polymers and in improving their usage areas. The aim of this study is to improve physico-chemical, and thermal behavior of poly(lactic acid) / poly(ε-caprolactone) (PLA/ PCL) blend by doping nano-graphite (NG) with different amounts and make the characterization of these nano-composites. It was observed that NG affected the temperature at which nanocomposites decompose. Also, the nanoparticles incorporated in the polymer blend become locked between the polymer filaments, speeding up the composites' decomposition. NG has significantly higher melting and evaporation temperature than PLA and PCL, so more residues were left as the quantity of NG rose. There was no significant change in the Tg and Tm peaks in the DSC experiment due to the inclusion of NG. While the NG particles raised the enthalpy of phase transition in general. The sharpness of the XRD peaks and the crystallinity of the nanocomposites both enhanced as the amount of NG in the blend was increased. Shape memory has been demonstrated to be a remarkable characteristic of thermos-sensitive PLA / PCL blend. Although the trained nanocomposite recovered most of its predetermined shape, increasing NG concentration in the composite may diminish its recovery behavior because.

  AtıfScopus22·WoS22·OpenAlex25

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• MakaleYalnız künye2022Scopus SJRQ2/r/munzur/2636
  Production and properties of epoxy matrix composite reinforced with hollow silica nanospheres (HSN): mechanical, thermal insulation, and sound insulation properties

  Demir, Eda; Güler, Ömer

  Hollow silica nanospheres (HSNs) have superior properties such as low density, low dielectric constant, low thermal conductivity, good sound absorption, dispersibility, fluidity, and stability. They have the potential to be utilised as a reinforcing material in the development of next generation composites due to their properties. Epoxy is one of the commonly utilised polymers in today’s technology. Production of epoxy matrix composite materials reinforced with particles having superior properties will open up new application areas for epoxy. In this study, mesoporous HSNs were produced. The mechanical, thermal and sound insulation properties of the composite were examined by reinforcing these mesoporous HSNs to the epoxy matrix. The epoxy matrix was reinforced with HSNs at 1 wt.%, 5 wt.%, and 10 wt.%. When the concentration of HSNs in the epoxy matrix was increased, its strength increased and its ductility decreased. While the non-reinforced epoxy had a tensile strength of 36.45 MPa, but the tensile strength of epoxy at the end of 10% HSN reinforcement reached 89.06 MPa. The strain % reduced in half. The sound insulation properties of epoxy improved as the concentration of HSNs increased. Thermal conductivity coefficient dropped up to a 5% reinforcement ratio, and then increased slightly at a 10% reinforcement ratio. The microstructure analyses indicated that when the reinforcement ratio increased, difficulties in the distribution of reinforcements to the matrix appeared. Furthermore, it was observed that when the matrix/reinforcement interface was improved, the properties of the composite improved.

  AtıfScopus14·WoS13·OpenAlex12

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• MakaleYalnız künye2021Scopus SJRQ2/r/munzur/2431
  Nanofiller reinforced biodegradable PHA/PLA composites: physico-chemical, thermal and dielectric properties

  Torğut, Gülben; Gürler, Nedim

  In this study, the electrical, thermal, morphological and physical properties of polyhydroxyalkanoate (PHA) and polylactic acid (PLA) blends and its nanocomposites prepared in different content of montmorillonite (3%wt, 5%wt, 7%wt) were investigated. Biodegradable blends of PHA/PLA were prepared in different compositions ranging from 30–70%. Nanocomposite films were analyzed by Fourier Transform Infrared (FTIR), Thermogravimetric Analysis (TGA), Differential Thermal Analysis (DTA) and scanning electron microscopy for morphology (SEM). The effects of the amount of MMT used as a reinforcing filler on the morphology, color, opacity, thermal stability, and dielectric properties of PHA/PLA films were investigated. SEM analyses showed good interaction between MMT and PHA/PLA film. As the MMT concentration increases, the transparency of the films decreases. In addition, MMT has improved thermal stability. Also, the dielectric properties and electrical conductivity of nanocomposite films were studied. The measurements were performed at frequencies between 100 Hz to 10 kHz at room temperature. As the frequency increased, dielectric permittivity (έ), the dielectric loss (ε'') and the electrical conductivity (σ) decreased and remain constant at high frequencies. έ, ε'' and the σ increased with increasing MMT content.

  AtıfScopus27·WoS22·OpenAlex28

  İncele
• MakaleAçık Erişim2021Scopus SJRQ2/r/munzur/2406
  Study on the thermal and electrical properties of novel poly[propyl acrylate-co-phenyl methacrylate] containing acetamido group

  Biryan, Fatih; Pihtili, Güzin

  In the available research, firstly a new 3-acetamido phenyl acrylate (APhA) monomer and a novel copolymer containing acetamido phenyl group were synthesized. 3-acetamido phenyl acrylate (APhA) monomer was acquired by the reaction of acryloyl chloride and N-(3-hydroxyphenyl) acetamide. 3-acetamido propyl methacrylate (AAPMA) monomer was prepared in our previous study. A series of copolymers were prepared using these monomers in different mole ratios by free-radical polymerization method at 70 °C The structure of P(AAPMA-co-APhA) copolymer systems was characterized by FT-IR and NMR techniques. Thermal characteristics of P(AAPMA-co-APhA) copolymers were evaluated through thermogravimetric analysis (TGA) and differential scanning calorimeter (DSC) in an N2 atmosphere. Due to the presence of the amide group, we can say that the polymer with the least weight loss and the highest residue percentage at 500 °C is poly(APhA). AC electrical conductivity and dielectric and electrical parameters were analyzed in a range of 100 Hz–20 kHz frequency. The dielectric constant values of poly(AAPMA-co-APhA0.63) and P(AAPMA-co-APhA0.30) were 4.98 and 4.57 respectively. According to the results, the dielectric value decreased as the APhA units increased.

  AtıfScopus5·WoS5·OpenAlex5

  İncele
• MakaleAçık Erişim2020Scopus SJRQ2/r/munzur/3231
  Electrical properties of two-armed poly(Ɛ-CL-co-BMA) composites filled with bentonite

  Pihtili, Güzin; Torğut, Gülben; Biryan, Fatih

  The dielectric and electrical conductivity properties of two-armed poly(Ɛ-CL-co-BMA) copolymer and adding bentonite forms were studied. The effect of the bentonite was investigated at different quantities (%3wt, %6wt, %15 wt). The measurements were performed at frequencies between 100 Hz to 10 kHz at room temperature, and the dielectric permittivity (ε′), the dielectric loss factor (ɛ″) and conductivity (σac) were calculated. ε′ and ɛ″ increased with increasing bentonite content. In addition, changes of susceptance (B) and impedance (IZI) were examined at different frequencies ranging from 100 Hz to 10 kHz in order to investigate the effect of bentonite loading. As frequency increases, (B) increases linearly, whereas IZI decreases and remains constant at high frequencies. Two-armed copolymer synthesized using ring-opening polymerization (ROP) and Atom Transfer Radical Polymerization (ATRP) and its composites prepared with bentonite were characterized by FT-IR, 1H-NMR and SEM. Thermal behaviors were examined by TGA and DSC methods and the effect of bentonite was discussed.

  AtıfScopus15·WoS14

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