Chemical Engineering / Kimya Mühendisliği
Permanent URI for this collectionhttps://hdl.handle.net/11147/14
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Article Citation - WoS: 6Citation - Scopus: 9Preparation and Characterization of Flexible Polyvinylchloride-Copper Composite Films(Smithers Rapra Technology, 2013) Kurt, Emrah; Özçelik, Cenk Yağız; Yetgin, Senem; Özmıhçı Ömürlü, Filiz; Balköse, DevrimFlexible PVC films are statically charged due to their low electrical conductivity. This creates fire threat during its handling. Conductive materials are added to films to prevent this. In the present study it was aimed to prepare PVC- copper composite films by sol gel technique and characterize the prepared films. It was aimed to increase the electrical conductivity of the films by adding copper powder. However, the copper particles settled down to bottom instead of forming a conductive network that covers the whole cross section. Thus at the film crosssection a plastic upper phase and a copper rich lower phase were present. The film did not conduct electricity due to this uneven distribution. The minimum volumetric and surface resistivities of the films were at the order of 109 ohm-cm and 1010 ohm square respectively.Article Citation - WoS: 1Citation - Scopus: 1Flexible Pvc-Silica Composites as an Adsorptive Material for Water Soluble Dyes(Smithers Rapra Technology, 2013) Ulutan, Sevgi; Yetgin, Senem; Balköse, DevrimMethylene Blue (MB) adsorption studies were performed on flexible Polyvinyl Chloride/Silica composites which were obtained by using plastisol-plastigel technology. Change of MB concentration in aqueous phase as the adsorption process advanced was followed by using visible spectroscopy. The diffusion of MB through the composites exhibited non-Fickian behavior with a diffusivity of 10-11 m2s-1. Making use of such PVC-silica composite sheets as column packing, the packing time will be reduced and the surface available for diffusion will be increased. © 2013 Smithers Rapra Technology.Article Citation - WoS: 12Citation - Scopus: 13Statistical Thermal Stability of Pvc(John Wiley and Sons Inc., 2010) Atakul Savrık, Sevdiye; Cansever Erdoğan, Beyhan; Balköse, Devrim; Ülkü, SemraExperimental design was used to optimize the processing parameters for the decomposition of poly (vinyl chloride). Factorial design and face centered composite design (FCC) were applied to determine the optimum conditions. A total of 10 g PVC powder was mixed with different amounts of zinc stearate (ZnSt 2) and natural zeolite and tested for thermal stability. Factorial fitted model was explained by first order pattern due to the significant main effect regression constants, and FCC model was described by second order model owing to higher order polynomial coefficients. FCC design was superior to factorial design as FCC considers not only its pure quadratic effects contribution but also its higher overall desirability for thermal stability of PVC. For factorial design the optimum conditions were determined as 163.06 mg for ZnSt2, 399.99 mg for zeolite, and 140°C for temperature with desirability of 0.933. However, 400 mg for ZnSt2, 333.24 mg for zeolite, and 140°C for temperature with desirability of 0.956 were obtained as the optimum conditions by FCC design. © 2010 Wiley Periodicals, Inc.Conference Object Citation - WoS: 18Citation - Scopus: 19Development of Synergistic Heat Stabilizers for Pvc From Zinc Borate-Zinc Phosphate(Taylor and Francis Ltd., 2009) Erdoğdu, Cem Aykut; Atakul, Sevdiye; Balköse, Devrim; Ülkü, SemraThe importance of flame-retardant and smoke-suppressed poly(vinyl chloride) (PVC) compositions is increasing gradually in the polymer industry since PVC releases smoke and toxic gases (hydrogen chloride, HCl) during heating at temperatures above 140°C with the result of dehydrochlorination reaction. In this study, the synergistic effects of zinc borate (ZB)-zinc phosphate (ZP) on the thermal stability of PVC were investigated using thermal techniques. The induction and stability time values of PVC plastigels were obtained at 140°C and 160°C. The results revealed that PVC plastigels having only ZP and ZB retarded dehydrochlorination of PVC compared with the unstabilized sample. However, the plastigels with both ZB and ZP had a superior synergistic effect on char formation of PVC. Since the induction periods of the samples having both ZB and ZP were higher than those of the unstabilized samples having only ZB or only ZP, the synergistic effect was observed.Article Citation - WoS: 8Citation - Scopus: 5Tin Soaps in Emulsion Pvc Heat Stabilization(John Wiley and Sons Inc., 2002) Arkış, Esen; Balköse, DevrimIn this study, the effect of a liquid stabilizer based on organotins on PVC heat stability is investigated. Control and films with tin soap heat stabilizer Sn500K were prepared by solvent casting and they were heated at 160 and 180°C for different time periods. X-ray fluorescence spectroscopy analysis showed that tin was present in Sn500K and it was lead-free. DSC analysis showed that glass-transition temperature of films with Sn500K increased from 67 to 75-85°C by heating for 15 min at 180°C. IR spectroscopy indicated that concentration of carboxylate groups of Sn500K decreased with heating. Films with Sn500K did not degrade for short heating periods; however, degradation occurred in long heating times. Low concentration of Sn500K was recommended, since at high levels incompatibility with PVC and acceleration of degradation was observed. In the high temperature range, control and stabilized samples degraded in the same manner in two steps