Sürdürülebilir Kalkınma Amaçları
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- MakaleYalnız künye2021Scopus SJRQ1Silane doped biodegradable starch-PLA bilayer films for food packaging applications: Mechanical, thermal, barrier and biodegradability properties
Gürler, Nedim; Paşa, Salih; Temel, Hamdi
In this work, pure potato starch (PPS) purified from waste potato starch, was recovered and used. PPS was modified by 3-APTMS (3-(aminopropyl) trimethoxy silane) to manufacture a crosslinked film. To obtain a bilayer PPS-3APTMS-PLA film, the polylactic acid (PLA) was employed with PPS-3APTMS by casting method. The resulting materials, PPS-3APTMS and PPS-3APTMS-PLA were characterized by attenuated total reflectance fourier transform ınfrared (ATR-FTIR), x-ray Diffraction (XRD), scanning electron microscopy (SEM), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA). The silane-doped bilayer films have more thermal stability compared to PPS. The mechanical, solubility, swelling, water vapor permeability, optical properties and biodegradability under controlled compost conditions were examined. When the tensile strength of the PPS, PPS-3APTMS and PPS-3APTMS-PLA films were evaluated, the tensile strength (TS) were to 1.017±0.35 MPa, 1.437 ± 0.19 MPa and 10.918 ± 1.30 MPa, respectively. The PPS and PPS-3APTMS films were not elongation at break, while it was found about 21.94 ± 9.48 for the bilayer PPS-3APTMS-PLA film. The solubility, swelling, water vapor permeability, and transparency decreased for bilayer films. The water vapor permeability of PPS, PPS-3APTMS and PPS-3APTMS-PLA films were obtained as 31.69±0.4 × 10−7 g s−1 m−1 Pa−1, 28.96±0.4 × 10−7 g s−1 m−1 Pa−1, and 14.26±0.3 × 10−7 g s−1 m−1 Pa−1, respectively. Then, the biodegradability of films was performed under controlled compost conditions for 46 days according to ISO-14,855 standard. The biodegradation of PPS, PPS-3APTMS and PPS-3APTMS-PLA was also calculated as 9.30%, 5.45% and 5.08%. Biodegradation of PPS-3APTMS film decreases compared to PPS. Furthermore, the biodegradation value of bilayer film, PPS-3APTMS-PLA, was also decreased due to the slower degradation tendency of PLA. The contribution to the reusability of waste starch and the modifying of starch for food packaging and coating applications are the novelty aspects of the current study.
AtıfScopus93WoS77OpenAlex90
İncele - MakaleYalnız künye2019Scopus SJRQ2Silver/Selenium/Chitosan-doped Hydroxyapatite coatings on biological NiTi alloy: In vitro biodegradation analysis
Say, Y.; Aksakal, B.
Abstract: Nitinol (NiTi) substrates were bioceramic coated by single layer Hydroxyapatite (HA), double layer HA/Silver (Ag) and double-layered HA/Selenium (Se)–Chitosan (Cht) substitutions by sol–gel method. Surface morphologies and adhesion strengths of the obtained coatings were characterized by means of SEM, EDX, XRD, and adhesion tests. Crack-free coatings were obtained in single layer-HA (S1), double layer HA/Ag (S2), and double-layered HA/Selenium–Cht (S3) coatings on NiTi alloys executed via the sol–gel method. Degradation behavior was analyzed in via simulated body fluid (SBF) environment by means of weight loss (%) and ion release rates for 1–4 weeks of immersion periods. The degraded coating particles were measured and metallic ions were detected quantitatively by an inductively coupled plasma–mass spectrometer (ICP–MS). The results show that such coatings could minimize and/or prevent the degradation of metallic ions and weight loss (%) from the coated substrates. From the overall results, HA/Ag double layer biocomposite (S2)-coated NiTi substrates revealed the highest adhesion strength and lowest weight loss and degradation. It was also shown in all groups that the Ni ion release from the NiTi substrates was prevented by the coatings. [Figure not available: see fulltext.].
AtıfScopus10WoS9OpenAlex11İncele - MakaleYalnız künye2017Scopus SJRQ1Biodegradation of hydroxyapatite coated Rex-734 alloy with silver and selenium/chitosan substitutions: In vitro analysis
Aksakal, B.; Say, Y.; Buyukpinar, Ç.; Bakirdere, S.
Hydroxyapatite (HA) based bioceramic coatings; such as single-HA, double layered with Silver-Ag, Selenium-Se and Chitosan substitutions on Rex-734 alloy were executed by using the sol-gel method. Surface morphologies and adhesion strengths of the obtained coatings were investigated and coating material weight losses and metal ion releases from the substrates were determined in SBF (Simulated Body Fluid) environment. The coatings were characterized by SEM, EDS, XRD and adhesion strengths between the substrate and bioceramic coatings were measured with adhesion tests. SEM analyses revealed that crack-free surface morphologies were obtained in all bioceramic coatings. The coatings were kept in SBF for immersion periods from one to four weeks and the weight loss (%) in coatings and changes in ion release rates were determined. HA/Ag double layered coatings applied on the Rex-734 alloy increased the adhesion strength and accordingly reduced the weight losses (%) of coating materials in SBF. Se/Chitosan double layered coatings were found to decrease the adhesion strength and increase the weight losses (%) in SBF. Additionally, all bioceramic coatings were observed to prevent the elemental ion release by physical barrier effect for the release of metal ions during the four weeks immersion period in SBF.
AtıfScopus12WoS11OpenAlex12İncele - MakaleAçık Erişim2017Scopus SJRQ2Monitoring the ethalfluralin biodegradation with certain bactofungi mixed culture
Ergüven, Gökhan Önder
In this study, the biodegradation of ethalfluralin (C13H14F3N3O4), which is the most preferred herbicide in sunflower farming in Thrace region in Turkey, is investigated. Bacteria and fungi were isolated in soil samples obtained in Thrace region, and a mixed culture was prepared using equal volume of microorganism cultures. Five different apparatuses, including sterile agricultural soil were setup and ethalfluralin in 1,500 µg/L concentration was added to each apparatus, and they were watered for 6 weeks with sterilized tap water. Drained water was then collected, and the filtrates were measured for chemical oxygen demand (COD), biochemical oxygen demand (BOD5), total organic carbon (TOC) and ethalfluralin. Furthermore, pH and dissolved oxygen (DO) concentration were measured. Study results demonstrated that the highest biodegradation was observed in the soil sample that contained 10 mL mixed microorganism culture and ethalfluralin. In this filtrate, ethalfluralin, COD, BOD5 and TOC removals were measured as 92%, 85%, 82% and 97% respectively. The DO level remained between 3.00 and 4.50 mg/L in the first 3 weeks for all cultures. After the third week, it increased to 5.8 mg/L in the 5 mL culture mixture and to 7.1 mg/L in the 2 mL culture mixture. pH results demonstrated, an increase during the first 3 weeks and pH values decreased for all culture mixture media due to the formation of carbonic acid.
AtıfScopus2WoS2OpenAlex2İncele