Araştırma Çıktıları / Research Outputs

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Alan Özelinde Sosyalleştirme Yaklaşımı Çerçevesinde Etkili Ebeveynlik: Annenin Duygusal Erişilebilirliği ile Gelişimsel Çocuk Çıktıları Arasındaki İlişki
This study aims to examine effective parenting within the framework of the domains-of_x0002_socialization approach. Three separate studies were carried out. In the first study, Domain_x0002_Specific Parenting Interview (DSPI) was developed to measure parenting quality in different socialization domains and its psychometric properties were examined. The deductive content analysis of the DSPI was carried out in the second study. In the third study, the replicability of the first study was tested, the interactions between different socialization domains were examined qualitatively, and the relations of mothers' knowledge on effective parenting and the quality of their parenting behaviors with developmental child outcomes were examined. The participants of the first study consisted of 82 mothers with children between 35-76 months. The participants of the second study consisted of 50 mothers, which were randomly selected from the data set of the first study. The participants of the third study consisted of 141 mothers and fathers, who have children aged between 47-72 months. The findings of the first study provided evidence that DSPI is a valid and reliable measurement tool. The qualitative findings of the second study showed that the domains-of-socialization approach and the daily life interactions of mother-child dyads were mostly consistent. The third study showed that the quality of parenting behaviors in different socialization domains were related to various child outcomes through emotion regulation and inhibitory control.
Dolgu Maddesi Eklenmesiyle İletken Polimer Kompozitlerinin Hazırlanması
Within the scope of the project, conductive polymer composites with uniform filler distribution were produced by mixing thermoplastic polymers and carbon-based conductive fillers in molten form. Electrical, mechanical, thermal and morphological characterization of the produced composites were carried out. In the project experiments, conductive polymer composites of different compositions were prepared by mixing high-density polyethylene (HDPE), Nylon 6, Polypropylene (PP), Poly(ethylene thermthalate) (PET) polymer matrices, carbon black and multi-walled carbon nanotube particles in a twin-screw extruder. Test specimens were prepared using pressure and injection molding devices. The electrical properties of the samples were determined using two- and four-point probe conductivity measurement methods. During the mechanical characterization processes, tensile and impact strength tests were applied to the composites. Thermal properties were examined using DSC (diffrential scanning calorimetry) device. Morphological features were examined by SEM (scanning electron microscope). The electrical conductivity of insulating thermoplastic polymers has been reduced to the semiconductor level. The lowest critical concentration value (0.25% carbon nanotube by weight) was obtained in the PET-carbon nanotube composite system. The mechanical properties of composites have changed with the addition of fillers. The best improvement in mechanical properties was observed in PP-based composites. In general, as the amount of filler in the composites increased, the percentage of crystallization decreased.
Donör-akseptör düzeninde yeni bir bileşik grubununtasarımı, sentezi ve iletken polimerlerinin uygulama alanları
Chemical Engineering
Donor-acceptor-based electrochromic polymers, unknown in the literature, were synthesized and the optical and electrochemical properties of these materials were examined. In this study, in which both the donor effect and the acceptor effect were examined, soluble and processable materials with colors such as green, blue, cyan and black, although very few in number in the literature, were synthesized which are indispensable for their application areas. Necessary characterization studies have been carried out for the anticipated technological applications.
Erken Dönem Ebeveynlik Desteği: Anne Duyarlığı ve Güvenli Bağlanmayı Arttırmaya Yönelik Müdahale Programı Uygulaması
Previous research has shown that caregiving behaviors that are ‘sensitive’ can be increased through positive feedback based systematic interventions. This project aims to adapt, implement, and empirically test the effectiveness of the VIPP: Video-Feedback Intervention to Promote Positive Parenting (Juffer et. A., 1993; 2008), which has been shown to be highly effective in a vast number of studies in enhancing positive parenting practices and maternal sensitivity in the Western cultures. First, interveners were certified through training and the translation of the manual, tests and other related documents were completed, and then the research was conducted in two major cities of Turkey, Ankara (n = 76) and İstanbul (n = 27) for two years. Mothers (N = 103) were coming from low-SES backgrounds. Using a randomized control trial design, mother-child dyads were randomly assigned to the intervention (n = 63) and control (n = 40) groups. A number of video recordings, observational assessments, and self-report measures were employed in the periods of pretest, posttest, and follow-up. Maternal sensitivity and child’s attachment security were assessed through observation-based measures. Mothers were also asked to complete a set of self-report measures assessing child temperament and psychological adjustment as well as their parental stress, relationship satisfaction, and own attachment orientations. Results have shown that mothers and children in the intervention and control groups were not significantly different in terms of their basic characteristics in the pretest. GLM Repeated Measures analyses using 2 factor (intervention X control) X 3 time (pretest, posttest and follow-up) yielded significant differences on three out of 10 main outcome variables. Specifically, interaction effects were significant on Ainsworth Sensitivity Scale, self-reported maternal attitudes toward sensitivity, and marital satisfaction, indicating that mothers’ sensitivity and related attitudes were positively changed and their marital satisfaction were enhanced following the intervention. Additional analyses that were conducted comparing the pretest and posttest as well as pretest and follow-up measures within the control and the intervention groups separately, suggested that the levels of maternal sensitivity measured by the MBQS, and the child attachment security measured by the AQS have increased in the intervention group in the posttest and follow-up periods. Moreover, children’s internalization problems significantly decreased in the intervention group. Finally, to better understand the effectiveness of the VIPP, potential risk groups (High Risk vs. Low Risk) were created using the median split on a number of variables, such as the level of psychological symptoms and attachment avoidance. The findings suggested that compared to the control group, mothers who were categorized in the high-risk groups benefited more from the intervention. Overall, xi results have demonstrated that the effectiveness of the VIPP application had a moderate effect size and may have higher effect size if it is applied to the mothers from disadvantaged groups. The limitations of the study, suggestions, and directions for both future interveners and researchers were discussed. In sum, within the scope of the current project, an effective intervention instrument targeting to enhance maternal sensitivity and child security in the early years of children in Turkey has been adapted and validated as well as a number of measures were provided for the future interveners and researchers in this arena.
Kimyasal ışıl-ışıma özelliğine sahip heterosiklik monomerlerin ve iletken polimerlerinin sentezlenmesi ve uygulama alanları
Chemical Engineering
A new group of compounds with chemiluminescence properties were designed and synthesized, and after their identification, their behavior towards metal ions was examined. Some of these compounds, which are likely to be used in both analytical chemistry and forensic science, have been successfully polymerized by electrochemical methods and their optical and electrochemical properties have been identified.
Kurşun İçermeyen Yeni Nesil Primer Patlayıcı Tasarımı, Sentezi ve Karakterizasyonu
Chemical Engineering
Mercury fulminate, lead azide and lead styphnate have been used as primary explosives for a long time. They are very good initiatory explosives, however, they have some serious drawbacks such as thermal, hydrolytic, chemical instability, highly sensitive to light, high toxicity of the compounds themselves, high sensitivity to mechanical stimuli. Today, improvement on the existing primary explosives is essential to find materials without heavy metals with safer production line and more efficient use compared to the present ones. The main aim of this study is to synthesize and explore the initiating performance of novel energetic organic and metallic compounds, which lead to providing the similar or even better performance with lower toxicity. For this purpose, 5-(kloronitrometil)-4-nitro-1H-imidazol ligand and its cobalt, copper, iron and zinc complexes in different geometries were synthesized. The characterization of the complexes was elucidated by elemental analysis, ESI-MS, IR and 1H-NMR spectroscopy techniques. The geometric and electronic properties of the complexes were determined using gas phase density functional theory calculations. Then, the explosive properties of the energetic materials obtained were studied with theoretical methods. The thermal stability of the materials was investigated by TG-TA methods. Explosion safety tests of the two most suitable complexes having exothermic energy profile were completed in the form of service procurement. The results obtained showed that the prepared complexes have very high thermal stability, they do not show the ability to be a primary explosive. However, the complexes having exothermic properties can be used as propelling power, and the complexes having endothermic properties can be used as additives to increase thermal stability against impact and friction in high energy rocket fuels.
Plastikleştirilmiş Poli(Laktik Asit)’in alev dayanımının fosfor bazlı katkı maddeleri ile geliştirilmesi
The aim of this study is to improve the flame resistance and toughness of PLA by adding small amounts of different flame retardant additives and plasticizers at the same time. Poly(ethylene glycol) (PEG) was used as a plasticizer. Phosphate-based chemicals as flame retardant additives; ammonium polyphosphate (APP), boron phosphate (BP) and tri-phenyl phosphate (TPP) were used. Within the scope of the project, the synergistic effects of the double and triple compositions of these flame retardant additives were also examined. The mixtures are produced by melt blending and injection molding methods. The effect of the type and composition of flame retardant additives on the properties of PLA composites was determined by various mechanical, thermal and flammability tests.
Preparation of magnetic nanoparticles which enable the use of 18F-FDG as multi-modal imaging agents in PET-MRI applications/18F-FDG nin PET-MR görüntüleme uygulamalarında multi-modal görüntüleme ajanı olarak kullanılmasına yönelik manyetik nanoparçacıkların hazırlanması
Chemical Engineering
It is becoming increasingly evident that PET-MRI multi-modal imaging systems have great potential in practical medicine and for basic scientific research. Consequently there is a wide interest in developing proper imaging agents for these applications. Superparamagnetic iron oxide (SPIO) nanoparticles are already, extensively, being used as MRI contrast agents. The labeling of these nanoparticles with radioactive isotopes provides a new generation for MRI agents. Combination of the required properties, in the body of the same sample for both measurement techniques, ensures that both images are coming from the same spot and simultaneously. This approach provides more accurate and reliable data for diagnosis and treatment of the illness. One of the candidates of the applicable radioactive isotopes is 18F, an easily available one and is being produced in our country. However its chemical binding to delivery agents requires several steps of exhaustive chemical treatments. A laboratory/firm which tends to fabricate iron oxide nanoparticles labeled with 18F should reconstruct a new manufacturing plant, which needs a laborious and a quite expensive operation. Instead, a new process, which can convert already available PET contrast agents into PET-MRI agents without requiring any special expertise, would be more practical and economical.
Preparation of Novel Nanostructures with High Light to Heat Conversion and Investigation of their Fhotothermal Efficiencies and Toxicities/Yakın Kızılötesi Bölgede Yüksek Işık-Isı Çevrimine Sahip Özgün Nanoyapıların Hazırlanması, Fototermal Etkinliklerinin ve Toksisitelerinin Araştırılması
Chemical Engineering
Cancer is known as one of the main causes of death and according to Centers for Disease Control and Prevention Organization accounted for 8.2 million deaths worldwide in 2012 with an increasing incidence rate. For this reason, progressing efficient therapeutic strategies with low toxicities to eradicate tumours specificly, is considered as the main object in the cancer treatments. Poor specificity toward malignant tissues, systemic side effects, low efficacy and drug resistance are the well-known disadvantages of widely applied radiation and chemotherapies. Thus, to improve the cancer therapy, it is expected that the therapeutic methods should eliminate only diseased cells/tissues without causing collateral damage selectively. The development of new protocols for biomedical application are encouraged by advanced nanotechnologies and production of novel nanomaterials. When it is compared the conventional tratment like surgery, radiation therapy, and chemotherapy with nanoparticle approach, nanoparticle treatments are minimally invasive and should result in minimal side effects. Accordingly, novel and effective therapeutics with unique light-to-heat conversion property of nanoscale materials can be utilized for cancer treatment. Among them, near-infrared (NIR) region photothermal therapy (PTT) has become more popular and developed quickly due to minimally invasive treatments for patients. Generally, photothermal therapy depends on the photosensitizers taken up by cancer cells to transfer light to heat, leading to photoablation of the cells and subsequent cell death. Therefore, photosensitizing agents are a key factor in photothermal therapy. In PTT, due to its easy operation, ability to be locally focused on a specific region and minimal absorbance by skin and tissues to allow for noninvasive penetration of reasonably deep tissues, near-infrared (NIR) light (700–1000 nm) is preferred. Recently, due to their high photothermal conversion efficiency and the ease of synthesis and modification, inorganic based fotothermal therapy agents (PTA) have received great interest. Among them, gold nanoparticles (AuNPs) are considered as a special photosensitizer due to their strong localized surface plasmon resonance (LSPR). Different types of Au nanoparticle based photosensitizers in photothermal therapy, like nanorods, nanocages, and nano-core–shells, nanostars have been reported. Unfortunately, the problem related to the potential toxicity induced by photothermal agents (especially for carbon nanotubes or graphene, CTAB coated Au rods, copper sulfide crystals and iron oxide nanoparticles (Fe3O4 NPs), is still an unresolved debate, which will inevitably limit future clinic applications of PTT. Therefore, it is significant to explore an effective fototermal therapy agent in order to decrease the extra-high-dose nanoparticles used in photothermal ablation of cancer with NIR irradiation which can generate potential toxicity to the body. In addition, with the presence of effective agents in the near infrared region, deeper cases may be treated with photothermal therapy. In this project proposal, it is aimed to develop novel photothermal therapy agents, which can reduce toxic effect, using in very small quantities, by increasing the light to heat conversion efficiency and be able to provide treatment even in deeper case due to the effective light to heat conversion in the near infrared region (NIR) because of the different and improved plasmon resonance properties than the photothermal agents in the literature.For this it is planned to prepare 6 different phototermal agent and detection of the efficiencies of them in photothermal therapy. The first two of these structures will be formed by adding gold (AuNPs) and gold-silver bimetallic nanoparticles (AuAgNPs) of 1-3 nm in size onto the hollow gold nanoparticles (Hollow AuNPs) with a 60-100 nm size and 5-10 nm shell thickness (AuNPs/HollowAuNPs(1. agent), AuAgNPs/HollowAuNPs (2. agent)). The third and fourth agents will be prepared by adding gold nanoparticles and gold-silver bimetallic nanoparticles of 1-3 nm in size on magnetic iron oxide nanoparticles coated with a thin silica shell (AuNPs/Fe3O4-SiO2 (3. agent) ve AuAgNPs/Fe3O4-SiO2 (4. agent)). The proposed last two agents will be formed with the addition of gold nanoparticles and gold-silver bimetallic nanoparticles onto the resulting structure formed by the addition of gold shells over the thin silica layer coated iron oxide nanoparticles (AuNPs/AuShell/Fe3O4-SiO2 (5. agent), ve AuAgNPs/AuShell/Fe3O4-SiO2 (6. agent)). Characterization of the photothermal therapy agents will be done by using HR-TEM, XPS, VSM, ICP-OES, XRD, UV-Vis, Raman. The photothermal effects of the prepared structures will then be measured by using an 808 nm wavelength laser irradiation in solution and then their activity in the cancer cell line (in vitro) will be investigated. Finally, toxicity studies of photothermal agents will be carried out.
Quorum Sensing Inhibitör Özelliği Gösteren Yeni Moleküllerin Sentezi ve Çevreci Hidrojel Boya Sisteminde Kullanımı
Chemical Engineering
Bacteria present in the seawater quickly form a biofouling on the surfaces immersed in it. This process starts with the adhesion of organic nutrients such as protein and carbohydrates to the surface in the first seconds. Bacteria adhere to the nutrient film on the surface and form a protective biofilm of proteins and polysaccharides around them. The biological fouling process continues with the adhesion and development of diatoms (microalgae), macroalgae spores and macroorganism larvae such as of mussels. However, this sequential model is not valid in all cases. Biological fouling limits the maneuverability of water vehicles, increases fuel consumption and greenhouse gas emissions. Therefore, antifouling methods are important in terms of economy and environment issues. One of the methods to prevent microfouling on surfaces is to prevent communication between bacteria. Bacteria communicate with each other through "Quorum Sensing" (QS) molecules to permanently attach to surfaces. Gram-negative bacteria use acylated homoserine lactone (AHL) molecules for QS communication. Molecules resembling AHL have the potential to inhibit QS. Hydrogels with a three-dimensional polymer network are also considered promising coatings with high antifouling performances against marine organisms. The super hydrophilic property of hydrogel materials enables them to absorb large amounts of water into three-dimensional polymeric networks and form a hydrated layer on their surface, which can prevent the adhesion of micro or macroorganisms. For these reasons, in order to solve the problem of biological fouling within the scope of the proposed project, it is aimed to synthesize and characterize new QS analogs that will prevent bacteria from forming biofilms and settling on surfaces. As a result of the bacterial tests, the two compounds with the best antibiofilm properties will be used as biocides, and a water-based hydrogel paint formula with anti-QS properties will be developed. With the hydrogel technology, it is aimed to significantly reduce the friction force, fuel consumption and emissions together with the biofouling on the ship surface. The hydrogel paint designed within the scope of the project is water based, self-curing, can be easily applied to a ship surface by brushing or spraying and can be produced in powder form. Environmentalist methods were chosen in both synthesis stages. The use of organic solvents that cause volatile organic compounds (VOCs) to be released into the atmosphere is avoided.
Sürekli Nanomalzeme Üretimi için Alev Aerosol Reaktör Tasarımı, Kontrolü ve Simülasyonu
Due to its advantages compared to the wet chemistry methods, Flame Aerosol Technology is used to produce 90% (by volume) of the commercial nanomaterials continuously in a faster, cheaper way, and in a single step [1-2]. Evolved by combining combustion and aerosol technologies, a large span of materials from salts to metal oxides can be produced by this method [3]. In this technology, the most important issue is to produce the desired phase in the desired purity and morphology, and to understand the effect of the process parameters that control these properties. This is mostly because it takes place at very high temperature, where momentum, heat and mass transfer phenomena take place simultaneouly, as well as the combustion of fuel and the reaction of the metal salts in the flame. In order to apply this fast and high temperature process to the industrial scale, there is a need for well controlled laboratory experiments that allows to produce models which can be used to simulate the experimental results. In this proposal, a well controlled flame reactor will be designed, and the effect of the operation conditions on the final nano particle size, morphology and crystal phase will be investigated. The aim is to control the process conditions in a way that allows the tailor-made nanoparticles especially for heterogeneous catalytic applications. Computational Fluid Dynamics package FLUENT will be used along with a user defined “population balance” model in order to estimate the nanoparticle size, and compared with the experimental results. A new reactor will be designed and constructed with the help of the simulation, and metal oxides (e.g. TiO2, Pd/Co3O4 ) will be produced under different operating conditions. The nanoparticles produced will be characterized for their size and morphology, and the validity of the simulation model will be checked.
Synthesis and Applications of High Sulfur Content Polymeric Materials/Yüksek Kükürt İçerikli Polimerik Malzemelerin Sentezi ve Uygulamaları
Chemical Engineering
Sulfur has been used in various applications. With approximately 70 million tonnes produced each year from petroleum refining, elemental sulfur is widely available and inexpensive (∼$120 USD per tonne). A significant portion of sulfur is used in the production of sulfuric acid. Although elemental sulfur is not toxic, it is a flammable solid so finding productive uses for this stockpiled material under the open air is important. Finding large-scale uses for this sulfur, such as conversion to useful polymers, would be an important advance. Polymerization of elemental sulfur has long been studied. Sulfur polymerizes above 159 oC. Unfortunately, the polymeric sulfur undergoes depolymerization since elemental sulfur is more stable thermodynamically at room temperature. As a solution for this problem, in Pyun’s pioneering study, an alkene was used as an organic cross-linker via inverse vulcanization method. In this study, sulfur was heated to 185 °C to initiate ring-opening polymerization and then, addition of alkene resulted in cross-linking. Because of the high sulfur content (50-90 wt%) and the corresponding polysulfur copolymers represented several interesting chemical, material, and optical properties: redox acitivity (cathode materials for Li-S batteries), a high refractive index and a mid IR region of transparency (night vision, thermal imaging), self healing, heavy metal ions remediation, etc. These usage areas have inspired further exploration of inverse vulcanization with a variety of unsaturated cross-linkers to obtain polysulfides with various properties. On the other hand, today vegetable oils are the most important renewable raw material for the chemical industry. About 80% of the global oil and fat production is vegetable oil. These oils make highly pure fatty acids available such as oleic acid (OA) from sunflower, linoleic acid (LA) from soybean, linolenic acid (LnA) from linseed, and ricinoleic acid from castor oil (Figure 1.1(a)). Vegetable oils are expected to play a key role during the 21st century to synthesize polymers from renewable sources. Within this contribution, the project is aimed at the synthesis and application of new high sulfur content polymeric materials using fatty acids (Figure 1.1(a)). Figure 1. (a) Chemical structures of some fatty acids, (b) the synthesis and chemical modification (poly(S-r-OA)-PE) of a polsulfur copolymer (poly(S-r-OA)) via inverse vulcanization. Due to the presence of double bonds, these pure fatty acids will be used firstly for cross-linking by using inverse vulcanization method (Figure 1.1(b)). Correponding copolymers are expected to be soluble in common organic solvents, processable and electroactive. In particular, the effect of double bonds and the free alkyl chains on the polysulfur copolymers will be investigated systematically by using OA, LA and LnA. Another feature of the copolymers obtained from these fatty acids will be the presence of reactive functional units (-COOH), which makes it possible to make chemical modifications (amide, ester, etc. linkages) of the polysulfur copolymers and to convert them into new polymers with different properties. With this project, the first examples of high sulfur content derivatives of polyesters and polyamides (like poly(S-r-OA)-PE) may have been synthesized by the chemical modification (esterification and amidation) of polysulfur copolymers. After inverse vulcanization process, the characterization of the obtained polysulfur copolymers will be done by using NMR, Raman, FTIR, UV, GPC, SEM, DSC, TGA etc., techniques. Electrochemical, optical, and material properties of the polymers will be investigated and tested as potential promising materials for use in Li-S batteries, heavy metal ions remediation and photocatalytic dye removal. The properties of obtained polymers will be compared with each other as well as with the literature data. Lastly, studies will be carried out to produce polymers in kg scale, and the applicability of the method to be applied to the industry will be tested. With reaching the project targets, it will be possible to polymerize elemental sulfur with the renewable vegetable fatty acids; therefore, huge amounts of sulfur can be used more effectively and an important step for sustainable synthesis/production in the polymer industry will be realized.
Synthesis And Applications of New Conjugated Polymeric Materials Based on Carborane
Chemical Engineering
Combination of conjugated polymers and carborane units under the same roof was taken place recently, for the first time in 2003. In very few number of studies in the literature, it was reported that carborane units gave thermal, mechanical, optical and electrochemical stability to the condujugated polymers. In this study, in order to overcome the problems faced by the industrial field of conjugated polymers (insolubility, thermal, mechanical, optical and electrochemical instability, etc.) the inorganic and organic units will be melted in the same pot for producing new carborane based polymeric materials. In the first two years of the project, initially carborane based electron donor-acceptor-donor (D-A-D) type new inorganic-organic hybrid monomers will be designed and synthesized and then soluble conjugated polymers (low band gap, reversible electronic and optical properties, n- and/or p-type doping behavior, fast switching of various redox states and different colors and environmetally and thermally stable novel florescent conjugated polymers) will be tried to obtain by use of electrochemical and chemical methods. While alkyl substituted 3,4-propylenedioxythiophene and carbazole units will be used as D unit, carborane units will be used as A unit. Tetrabutylammonium salts (perchlorate, tetrafluoroborate and hexafluorophosphate) as the supporting electrolyte and acetonitrile, dichloromethane and/or propylene carbonate will be used as the solvent in the electrochemical polymerization. For the chemical polymerization, Stille Coupling, anhydrous FeCl3 and / or CuI oxidant and/or Yamamoto type Ni (0) dehalogenation polymerization techniques will be used. After the investigation of the electrochemical, optical and thermal properties of the obtained polymeric materials, studies for the industrial and technological applications (electrochromic devices and light emitting diodes (LEDs)) will be done at Atılım University and METU by experienced teams in the last two years of the project. When the materials designed in the project are moved successfully to the industrial fields such as electrochromic devices and LED applications, it will be brought to a solution to an industrial problem by using carborane chemicals. As a result, it will be the primary purpose and goal of our project to overcome the problem faced by industrial areas (electrochromic devices and LEDs) with the products based on special carboranes, which can be synthesized in our country.
Synthesis and Polymerization of Monomers possessing Chemiluminescence Properties and Their Application Areas
Chemical Engineering
A novel class of chemiluminescence (KL) compounds was designed, synthesized and characterized; 2,3-dihydro-thieno[3,4-d]pyridazine-1,4-dione (T-Lum), 2,3-dihydro-furo[3,4-d]pyridazine-1,4-dione (FLum) and 2,3-dihydro-pyrrolo[3,4-d]pyridazine-1,4-dione (P-Lum). The KL reaction of the compounds in alkali medium was examined by using hydrogen peroxide and potasium permanganate oxidants and a possible KL mechanism was investigated. Synthesized compounds are especially sensitive to Fe+3 ion and this property makes them amenable to use as iron sensors. Also, the sensitivity of these materials towards iron makes them a promising candidate in forensic area to detect trace amount of blood at crime scene. Compounds are also sensitive both iron and blood samples even at lower concentration. By using the sensitivity of compounds towards hydrogen peroxide, the detection of many analytes will be possible. Beside the KL property, the electrochemiluminescence (EKL) property of the materials makes them very precious. Since the oxidation of pyridazine ring occurs before the aromatic rings, electropolymerization of the functionalized pyrrole, furan and thiophene compounds with pyridazine rings were not possible. To overcome this problem, new compounds, which have lower oxidation potential than that of pyridazine ring, were designed, synthesized and characterized; 5,7-di-tthiophen-2-yl-2,3-dihydro-thieno[3,4- d]pyridazine-1,4-dione (TTT-Lum) and 5,7-di-ethylenedioxythiophene-2-yl-2,3-dihydro-thieno[3,4- d]pyridazine-1,4-dione (ETE-Lum). The materials synthesized in the form of donor-acceptor-donor exhibit both KL and EKL properties, which makes them promising candidates in the analytical chemistry and forensic science. Compounds were polymerized successfully without oxidizing pyridazine ring via electrochemical polymerization (only neat BF3-Et2O solution or 0.1 M LiClO4 or 0.1 M tetrabutylammonium perchlorate dissolved in acetonitrile containing 5% of BF3-Et2O by volume ) and the electrochemical and optical properties were investigated. Electroactive and electrochromic polymeric materials, exhibiting reversible redox behaviours, have lower band gaps between 1.6 and 1.7 eV. Also, the polymer films are very stable; the electroactivity and the EKL properties were remain unchangeable after many cycles. Furthermore, the soluble polymer films in alkali medium with their KL properties will attract many attention in the academic areas.
Synthesis, Characterization and Applications of Various Aromatic Polythioureas via Multicomponent Polymerization
Chemical Engineering
In recent years, multicomponent polymerization (MCP) method has attracted the attention of researchers due to its simple operation, high atom economy, high polymerization efficiency and high molecular weight of polymers without using catalyst under moderate conditions. In the MCP method used in the synthesis of different polythioamides and polythioureas, one of the reactants is aliphatic amines and unfortunately aromatic amines are not used directly. Due to this reason, in polythioamide syntheses, it is seen that aromatic diamines do not react with alkynes in the presence of elemental sulfur and therefore they are converted firstly to aromatic diisocyanides and this increases the cost of synthesis. There is no study on the use of aromatic diamines directly in the synthesis of polythioureas. In the light of this information, it is aimed to use the MCP method which is thought to be an economic and effective method for the use of elemental sulfur and aromatic diamine directly to obtain well defined, functional and workable polymeric structures without using catalyst in the project. In the MCP method, diisocyanides which are more reactive than the dialkyne reactant used previously will be used. The reactivity of diisocyanides to aromatic amines was supported by literature data and preliminary studies performed by our group. In addition, elemental sulfur, one of the most abundant elements in the world, is a non-toxic and stable solid under normal conditions and is an inexpensive substance that is readily available even at high purity grades. The use of aromatic diamines directly with elemental sulfur is very interesting in terms of practical, cost-effective and synthetic compatibility. With the use of aromatic diamines in the MCP method, the gateway for the synthesis of different polythioureas will be further expanded. For this purpose, the synthesis of 10 different polythioureas shown below will be carried out and characterization of the obtained products (NMR, FTIR, GPC, SEM, UV-Vis, DSC, TGA) will be performed. The data obtained will be examined comparatively with the methods used before for the synthesis of polythioureas. Due to today's polluted environment and limited energy reserves, it becomes important to develop highly efficient renewable technologies, green energy sources and environmentally friendly methods for environmental remediation and energy production. In this direction, hydrogen production becomes so important in the field of energy. In addition, the removal of heavy metals found in nature and organic matter in waste water is of great importance in environmental remediation. From this point of view, the preparation of nanocatalysts that will allow hydrogen production and removal of organic substances and materials that provide heavy metal removal attracts the attention of scientists. Thanks to the thiourea functional groups in the structure of different polythioureas to be synthesized by the MCP method, it can be used in mercury treatment (due to the ability of the thiourea groups and mercury ions to be complex) as well as to be used as support materials for the production of silver, palladium and copper nanoparticles. In this respect, firstly mercury removal capacity of the prepared polymers will be investigated. Then, the polymer-metal nanoparticle hybrid materials (4 different structures, polymer/AuNPs, polymer/AgNPs, polymer/CuNPs and polymer/PdNPs)) will be obtained by adding gold, silver, copper and palladium nanoparticles (separately) onto the polymer having the highest metal ion-holding capacity. The stability, catalytic activity and the effect of the interaction on the catalytic activity of the polymer/metal nanoparticle hybrid materials will be investigated in hydrogeneration from amine borane and photocatalytical removal of dye molecules founded in waste waters, respectively.
Synthesis, Characterization and Applications of Various Aromatic Polythioureas via Multicomponent Polymerization/Çok Bileşenli Polimerizasyon Yöntemi ile Farklı Aromatik Politiyoürelerin Sentezi, Karakterizasyonu ve Uygulamaları
Chemical Engineering
In recent years, multicomponent polymerization (MCP) method has attracted the attention of researchers due to its simple operation, high atom economy, high polymerization efficiency and high molecular weight of polymers without using catalyst under moderate conditions. In the MCP method used in the synthesis of different polythioamides and polythioureas, one of the reactants is aliphatic amines and aromatic amines are not used directly. Due to this reason, in polythioamide syntheses, it is seen that aromatic diamines do not react with alkynes in the presence of elemental sulfur and therefore they are converted firstly to aromatic diisocyanides and this increases the cost of synthesis. There is no study on the use of aromatic diamines directly in the synthesis of polythioureas. In the light of this information, it is aimed to use the MCP method which is thought to be an economic and effective method for the use of elemental sulfur and aromatic diamine directly to obtain well defined, functional and workable polymeric structures without using catalyst in the project. In the MCP method, diisocyanides which are more reactive than the dialkyne reactant used previously will be used. The reactivity of diisocyanides to aromatic amines was supported by literature data and preliminary studies performed by our group. In addition, elemental sulfur, one of the most abundant elements in the world, is a non-toxic and stable solid under normal conditions and is an inexpensive substance that is readily available even at high purity grades. The use of aromatic diamines directly with elemental sulfur is very interesting in terms of practical, cost-effective and synthetic compatibility. With the use of aromatic diamines in the MCP method, the gateway for the synthesis of different polythioureas will be further expanded. For this purpose, the synthesis of 10 different polythioureas shown below will be carried out and characterization of the obtained products (NMR, FTIR, GPC, SEM, UV-Vis, DSC, TGA) will be performed. The data obtained will be examined comparatively with the methods used before for the synthesis of polythioureas. Due to today's polluted environment and limited energy reserves, it becomes important to develop highly efficient renewable technologies, green energy sources and environmentally friendly methods for environmental remediation and energy production. In this direction, hydrogen production becomes so important in the field of energy. In addition, the removal of heavy metals found in nature and organic matter in waste water is of great importance in environmental remediation. From this point of view, the preparation of nanocatalysts that will allow hydrogen production and removal of organic substances and materials that provide heavy metal removal attracts the attention of scientists. Thanks to the thiourea functional groups in the structure of different polythioureas to be synthesized by the MCP method, it can be used in mercury treatment (due to the ability of the thiourea groups and mercury ions to be complex) as well as to be used as support materials for the production of silver, palladium and copper nanoparticles. In this respect, firstly mercury removal capacity of the prepared polymers will be investigated. Then, the polymer-metal nanoparticle hybrid materials (4 different structures, polymer/AuNPs, polymer/AgNPs, polymer/CuNPs and polymer/PdNPs)) will be obtained by adding gold, silver, copper and palladium nanoparticles (separately) onto the polymer having the highest metal ion-holding capacity. The stability, catalytic activity and the effect of the interaction on the catalytic activity of the polymer/metal nanoparticle hybrid materials will be investigated in hydrogeneration from amine borane and photocatalytical removal of dye molecules founded in waste waters, respectively.

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