Sürdürülebilir Kalkınma Amaçları
Yayınlar
- MakaleAçık Erişim2022Karışmaz PMMA/PS harmanlarının optik özelliklerine uyumlulaştırıcı etkisi
Yilmaz, Ersen
Karışmayan polimetil metakrilat/polistiren (PMMA/PS) harmanları değişik maleik anhidrit-stiren-metil metakrilat (MAStMMA) uyumlaştırıcı oranı (0, 2, 4, 6, 8 ve 10) eklenerek çözeltiden döküm yoluyla elde edilmiştir. Spektral sonuçlar, kırılma indisi (n), sönüm katsayısı (k) ve absorpsiyon katsayısı (µ) gibi optik sabitlerin terpolimer bazlı uyumlaştırıcı ilavesiyle arttığını göstermiştir. Diğer yandan optik enerji boşluğu Eg, anılan optik sabitlere göre zıt bir eğilim göstermiştir. Gözlenen en düşük enerji boşluğu %8 ila %10 uyumlaştırıcı oranı arasında belirlenmiştir.
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İncele - MakaleYalnız künye2022Blending Effect of Maleic Anhydride-Styrene-Methyl Methacrylate Terpolymer on Polyvinylchloride (Pvc)/Polystyrene (Ps) Mixtures
Yilmaz, Ersen
The blending effect of poly maleic anhydride-styrene-methyl methacrylate (MA-St-MMA) terpolymer on nonmiscible PVC and Polystyrene was studied depending on their thermomechanical properties. Depending on the amount of the synthesized and used compatibilizer the tensile strength, modulus, and thermomechanical properties of the blends are enhanced. The unmodified and blends with small amounts of compatibilizer exhibit two-step degradation whereas those containing 6, 8 and 10 percent compatibilizer showed a single glass transition (Tg). All the results reveal that PS/PVC mixtures modified with MA-St-MMA have superior mechanical properties and phase adhesions than mixtures without terpolymer.
- MakaleAçık Erişim2022Viscometric Investigation of Compatibilizer Effect on Polyvinyl chloride/Polystyrene Blends
Yilmaz, Ersen; Boztuğ, Ali
In this study, polyvinyl chloride (PVC) and polystyrene (PS) polymers, which do not form a compatible blend with each other in certain concentration ranges and are widely used on an industrial scale, were used. The concentration range in which these two polymers do not form a compatible blend were determined viscometrically, and maleic anhydride-styrene (MAS) copolymer was added as a compatibilizing agent in this concentration range. The concentration range in which the polymer pair did not form a compatible blend was determined as 1.5 and 2.0 g dL-1. In this concentration range, 5.0 and 10.0 % MAS copolymer was added to the polymer couple and its compatibilizing effect was investigated. It was determined by viscometric method that the MAS copolymer was a good compatibilizer in the range where the polymer pair did not form a compatible blend.
AtıfOpenAlex1İncele - MakaleAçık Erişim2022Green Synthesis of Gold Nanoparticles Using Aqueous Extract of Asphodelus Aestivus, Coating with Chitosan Biopolymer and Cytotoxicity Studies
Ates, Mehmet; Yilmaz, Ersen; Erbay, Muhammed
The green synthesis of gold nanoparticles (Au-NPs) was carried out by pouring the aqueous extract of East Anatolian origin Asphodelus aestivus plant onto aqueous gold metal ions and reducing them via single-step one- pot method. The absorption peak of the synthesized nanoparticles gave a maximum at 575 nm. All the X-ray diffraction peaks at 2θ = 38.25 , 44.46 , 64.64 and 77.20 that index to (111), (200), (220), and (311) planes verify the successful synthesis of Au-NPs. Mostly spherical shape particles showed a homogeneous distribution with size range 20±5 nm are measured using TEM. From the FTIR spectrum, the peaks are seems to be related to phenolic compounds, flavonoids, benzophenones, terpenoids and anthocyanins which assume that they could act as the reducing agents. The plant extraction, one-pot, single-step method used is environmentally safe without the role of synthetic materials which is highly potential in mild and green synthesis applications. The Au-NPs were coated with chitosan biopolymer in aquatic solution medium and verified by SEM. Then, cytotoxic investigations of the biosynthesized Au-NPs were carried out by HUVEC cells. Au-NPs were showed toxic effects on cell culture, even if in a small amount. However, chitosan biopolymer coating increased cell viability.
AtıfOpenAlex3İncele - MakaleYalnız künye2022Scopus SJRQ2Compatibilization of polyvinyl chloride - polymethyl methacrylate polymer blends with maleic anhydride-styrene-methyl methacrylate terpolymer
Yilmaz, Ersen
In this study, nonmiscible polyvinyl chloride (PVC) and polymethyl methacrylate (PMMA) polymers were made miscible by using MA-St-MMA terpolymer as a compatibilizer. Maleic anhydride-styrene-methyl methacrylate (MA-St-MMA) terpolymer was synthesized in our laboratory and used. The synthesized terpolymer was determined by FT-IR spectroscopy. Equal mass PVC/PMMA mixture samples were prepared in series and the compatibilizer terpolymer varying between 2% and 10% by mass was added to the samples and the effect of the added terpolymer on the miscibility was determined viscometrically, thermally, mechanically and, visually. With the addition of the compatibilizer, the two components in the mixture behave like a single polymer with a single glass transition temperature (Tg) and the mixture became compatible. As a result of viscometric experiments, it has been determined that with the added MA-St-MMA terpolymer, the Δb value derivated from the Krigbaum-Wall equation which is the miscibility parameter of a mixture shifted into the positive (+) zone indicating that the two polymers became miscible. By visual analysis, it was observed that the added terpolymer reduced the opaque appearance and the phase separations of the mixture. From the tensile test, a significant improvement in impact toughness was observed. When all the data obtained were evaluated, it was determined that the synthesized MA-St-MMA terpolymer was a suitable compatibilizer for the mixture of PVC and PMMA.
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İncele - MakaleAçık Erişim2021Synthesis and Characterization of Silver Nanoparticles and Coating with Chitosan
Ates, Mehmet; Yilmaz, Ersen; Kar, Bulent; Durukan, Ilknur Kars
Recent advancements in nanotechnology have garnered increasing attention due to the improvements in producing and utilizing particles whose sizes are extremely small. There is particular interest in metal nanoparticles due to their distinctive properties. Silver nanoparticles (Ag-NPs) have been of particular interest owing to their unique electrical, optical and physicochemical properties as well as their biomedical applications. Ag-NPs are the fastest growing class of nanoscale materials because of their antibacterial activities. They are now considered to be the next generation antimicrobials. Today, owing to their disinfectant properties, Ag-NPs are extensively used in numerous consumer products, including disinfecting medical devices and home appliances, paints, optical devices, plastics, textiles, soaps and laundry detergents, cosmetics, health-care products, as well as in food packing and food products as preservative and anti-caking agents. Despite their widespread usage, the products containing Ag-NP additives are a serious environmental and human health concern because of their toxicity. Studies on cell and bacterial cultures have shown that Ag-NPs are toxic; and the toxic effects are mainly due to the dissolved Ag ions when Ag-NPs degrade in water. In this study, considering the criteria outlined above, the purpose of the study and Ag-NPs were chemically synthesized in the laboratory environment and modified as chitosan coating. UV-Vis spectroscopy, transmission electron microscopy, scanning electron microscopy, X-ray crystallography and zeta potential analysis were used to characterize the silver nanoparticles.
AtıfWoS3OpenAlex4TR Dizin3İncele - MakaleYalnız künye2020Scopus SJRQ2Synthesis and modification of amine-terminated maleic anhydride‑butyl acrylate copolymer and investigation of adsorption properties for cadmium (II) ions (Cd2+)
Yilmaz, Ersen; Erenler, Fatih Mehmet; Boztuğ, Ali
In this study, a maleic anhydride‑butyl acrylate copolymer (MA-BA) was synthesized using maleic anhydride (MA) and butyl acrylate (BA) monomers. The synthesis was carried out in methyl ethyl ketone by benzoyl peroxide as the initiator at 70 °C. Secondly, the MA-BA copolymer was chemically modified with ethylenediamine and abbreviated as NH2MA-BA. The copolymer and its modified structure were analyzed spectroscopically by FT-IR, thermally by Thermo Gravimetry (TGA) and by Differential Scanning Calorimetry (DSC). Solubility tests of both structures were performed. Then, the adsorption of cadmium ions (Cd2+) by the modified copolymer (NH2MA-BA) was studied. The copolymer and its modified structure were synthesized successfully, and this was proven by their FTIR spectra. The (MA-BA) copolymer is soluble in common organic solvents but (NH2MA-BA) is not due to cross-linking. The DSC and DTA results showed that chemical modification improved the structure thermally. It was shown that the Freundlich model was the best explanation for the adsorption type in correspondence with the experimental plots, and the modified copolymer is a good candidate for Cd2+ adsorption.
AtıfScopus8WoS7OpenAlex8İncele - MakaleYalnız künye2013Scopus SJRQ2Amine-modified maleic anhydride containing terpolymers for the adsorption of uranyl ion in aqueous solutions
Simsek, Selcuk; Yilmaz, Ersen; Boztug, Ali
Maleic anhydride-styrene-methyl methacrylate (MA-S-MM) terpolymer was prepared. It was modified by ethylenediamine (EDA) and diethylenetriamine (DETA) in order to get cross-linked polymers bearing carboxyl and amine groups. Modified polymers used as an adsorbent for the removal of UO2 (2+) from water. The characterizations of structures of all the polymers were performed by Fourier transform infrared. The adsorptive features of adsorbents were then investigated for UO2 (2+) in view of dependency on ion concentration, pH, temperature and kinetics. Experimentally obtained isotherms were evaluated with reference to Langmuir, Freundlich and Dubinin-Radushkevich models. The maximum monolayer adsorption capacity for UO2 (2+) was found to be 1.59 and 2.43 mol kg(-1) for EDA-MA-S-MM and DETA-MA-S-MM, respectively. It can be said that the new modified polymers prepared in our laboratory have been suggested as new adsorbents for uranyl ions.
AtıfWoS27İncele - MakaleAçık Erişim2013Scopus SJRQ4Effects of the Different Methacrylate Monomers on Bond Strength Between Soft Liner and Acrylic Resin
Bolayir, Giray; Soygun, Koray; Simsek, Selcuk; Yilmaz, Ersen; Dogan, Arife; Boztug, Ali; Dogan, Orhan Murat
In the present study, tensile bond strength between on acrylic resin and a soft liner, molloplast B, was studied. To enhance the bonding capacity between these materials, acrylic resin surface was modified using ethyl methacrylate, iso-butyl methacrylate or tert-butyl methacrylate monomers. The monomers were applied onto the surfaces of methacrylate components for 60, 120 or 180 s and the bond strength values were obtained. The values were statistically compared. Changes on the modified surfaces were investigated by fourier transform infared spectroscopy with attenuated total reflectance (FTIR-ATR). The highest bond strength value was obtained from 120 s treatments with ethyl methacrylate and the lowest value was obtained from 60 s treatments with iso-butyl methacrylate. These high alkyl monomers also had secondary interactions on the acrylic surfaces, evidenced by FTIR-ATR.
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