Search

The antibacterial ability of the organoclays prepared as an ingredient of the personal care product formulation was investigated. Four organoclay samples were synthesized using cationic surfactants; cetyltrimethylammonium bromide (CTAB), behentrimonium chloride (BT), cetylpyridinium chloride (CPC), and an anionic surfactant sodium lauroyl sarcosinate (SR) loading onto commercially available bentonite, Detercol® P2 (Mt-D). The antibacterial ability of the prepared organo-bentonite was investigated against Gram positive bacterium, S. aureus and Gram negative bacterium E. coli by using the Disk Diffusion Method and ASTM 2419 Standard Method under Dynamic Contact Condition Shaker Flask Analysis. While Mt-D had no antibacterial ability, Mt-D-CP exhibited the highest antibacterial activity against both S. aureus and E. coli. The other organoclays prepared had antibacterial activity mainly against Gram positive bacterium S. aureus. The characterization of the organobentonites using FTIR, XRD and SEM analyses showed that the surfactants could be loaded successfully into the bentonites. The results of the XRD analysis indicated that CP, and CP-SR molecules together delaminated the bentonite structure. On the other hand, BT and CTA molecules intercalated into Mt-D decreased the number of the platelets, however they did not delaminate the bentonite crystal structure completely. The SEM micrographs of the organobentonites showed the typical flower-shaped curly structure of bentonite except the Mt-D-CP-SR, which attained a fiber-like structure. It was investigated whether Mt-D-CP with approved antibacterial ability against S. aureus and E. coli would also show antibacterial activity in a personal care formulation matrix by preparing cosmeceutical facial mask with adding Mt-DCP in different concentrations. The antibacterial analysis showed that the formulation containing 45 % Mt-D-CP had the most effective antibacterial activity. It deduced that Mt-D-CP has a potential to be used in antibacterial applications., Kişisel bakım ürünlerinde kullanılmak amacı ile hazırlanan organo-killerin antibakteriyel özellikleri araştırılmıştır. Araştırmada dört tür organo-kil hazırlamak için ticari olarak bulunan bentonit türü kil Detercol® P2 (Mt-D) kullanılmış ve üzerine katyonik yüzey aktif maddeler setiltrimetilamonyum bromür (CTAB), behentrimonyum klorür (BT), setilpridinyum klorür (CPC) ve anyonik yüzey aktif madde sodyum lauril sarkosinat (SR) yüklenmiştir. Gram pozitif S. aureus ve Gram negatif E. coli bakterileri kullanılarak Disk Difüzyonu Metodu ve ASTM 2149 Dinamik Temas Koşullarında Antimikrobiyal Ajanların Antimikrobiyal Aktivitesinin Belirlenmesi İçin Standart Test Yöntemiyle bu çalışmada hazırlanmış organik-killerin antibakteriyel özellikleri incelenmiştir. Mt-D’nin her iki bakteriye karşı etkisiz, Mt-D-CP’nin her iki bakteriye karşı etkili, hazırlanan diğer organik-killerin de esas olarak Gram pozitif S. aureus bakterisine karşı etkili olduğu görülmüştür. FTIR, XRD ve SEM analizleri ile gerçekleşen organik killerin karakterizasyonu yüzey aktif maddelerin bentonit kiline başarıyla yüklendiğini göstermektedir. XRD sonuçları, CP ve CP-SR yüzey aktif maddelerinin bentonitin kristal yapısını dağıttığını, tabakalarını birbirinden ayırarak yüzeylerine adsorplandığını göstermiştir. BT ve CTA yüzey aktif maddelerinin ise adsorpsiyon esnasında tabaka sayısını azaltmakla birlikte kristal yapıyı tamamen dağıtmadığını ve bentonitin yüzey ve ara yüzeylerine yüklendiğini göstermiştir. SEM görüntülerinde Mt-D-CP-SR hariç tüm organik killerde bentonitin çiçek benzeri kıvrımlı yapısı görüntülenmiştir. Mt-D-CP-SR görüntülerinde ise dağılan bentonit parçacıklarının tekrar birleşme esnasında yeni lifli yapılar oluşturduğu görülmüştür. Farklı konsantrasyonlarda Mt-D-CP içeren bir yüz maskesi hazırlanarak, S. aureus ve E. coli’ye karşı etkili Mt-D-CP malzemesinin bir formülasyon içinde de etkinlik gösterip göstermeyeceğine bakılmıştır. % 45 oranında ilave edilen Mt-DCP ile en iyi antibakteriyel etkinlik görülmüş ve bu çalışma sonucunda MT-DCP’nin antibakteriyel yüz maskesi üretiminde kullanılabileceği sonucuna varılmıştır.

Cilj diplomskog rada bio je istražiti bentonitne gline sa sedam lokaliteta: Sjeničak, Paripovac, Lončarski vis, Divoselo (Hrvatska), Šipovo (BiH), Zaloška Gorica (Slovenija), Vranjska Banja (Srbija). Uzorci su analizirani metodom rendgenske difrakcije na praškastim uzorcima, infracrvenom (IR) spektroskopskom metodom, metodom kapaciteta zamjene kationa, termičkom analizom i kemijskom analizom. Dobiveni rezultati govore kako je u svim uzorcima kao glavni mineral zastupljen montmorillonit, dioktaedarski smektit. Osim motmorillonita se u nekim uzorcima pojavljuje i beidelit, kao dominantni mineral ili kao sekundarni mineral uz montmorillonit. Kemijskom analizom određen je volumni udio makro i mikroelemenata, iz čega je ishodišni materijal određen kao trahiandezit za sve uzorke osim Divosela koji je određen kao riolit. Main goal in this master thesis was investigation and interpretation of bentonite clays from seven sites: Divoselo, Sjeničak, Paripovac, Lončarski Vis (Croatia), Šipovo (Bosnia and Hezegovina), Zaloška Gorica (Slovenia) and Vranjska Banja (Serbia). Samples were investigated using XRD(X-ray diffraction) analysis on powder samples, IR (infrared) spectroscopy, CEC (Cation exchange capacity), thermal analysis and chemical analysis. The research showed that the main mineral in all samples is montmorillonite, dioctahedral smectite. Along with montmorillonite, in some samples there is also beidelite, found as main or secondary mineral to montmorillonite. Chemical analysis resulted with volume fraction of macro and microelements what gave us posibillity to calculate what the parent material was. Trachyandesite was parent material for all samples except Divoselo which evolved from riolite.

Tez (Yüksek Lisans) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 2015, Thesis (M.Sc.) -- İstanbul Technical University, Instıtute of Science and Technology, 2015, Günümüzde polimerlerin kullanımı oldukça yaygındır ve polimer üzerine yapılan çalışmalar gün geçtikçe artmaya devam etmektedir. Polimerler üzerine yapılan çalışmalarda nano ölçekteki katkıların, polimerin özelliklerini oldukça geliştirdiği de bilinmektedir. Doğal olarak tabakalı yapıda bulunan killerin polimer içerisinde dağılabilmesi nedeniyle çok iyi birer katkı malzemesi olabilecekleri anlaşılmıştır ve böylece kil/polimer nanokompozitlerin hazırlanması, karakterizasyonları ve özelliklerinin belirlenmesi üzerine yapılan çalışmalar başlamıştır. Bu çalışmada, farklı kil çeşitleri incelenip, kil parçacıklarının birbirleri ile etkileşimleri, reolojik ve elektrokinetik ölçümlerle araştırılmıştır. Montmorillonit, sepiyolit ve vermiküler killeri araştırılarak killerin birbirleri ile olan etkileşimleri ve özellikleri incelendikten sonra, PVA polimeri ile en kolay nanokompozit hazırlama yöntemi olan çözeltilerin birleştirilmesi yöntemi kullanılarak nanokompozitler hazırlanmış ve bu nanokompozitler film haline getirilmiştir. Hazırlanan bu nanokompozitlerin karakterizasyonu yapılarak nanokompozit oldukları anlaşılmış, daha sonra nanokompozit filmlerin özelliklerinin incelenmesiyle PVA polimerine vermiküler kilinin katkısıyla mekanik özelliklerinin, montmorillonit kili katkısıyla da termal özelliklerinin geliştiğini görülmüştür. Mekanik özellik çalışmada daha ön planda olduğu için, yapılan ölçümlerde vermiküler kilinin istenildiği gibi yüksek elastik modülüne sahip olduğu görülmüş ve vermiküler kilinin anyonik, katyonik ve nanyonik yüzey aktiflerle etkileşimleri incelenmiştir. Bu yüzey aktif malzemelerle dispersiyonları hazırlandı. Karakterizasyonu yapılan ve özellikleri incelenen bu numunelerde, anyonik yüzey aktif SDS ve katyonik yüzey aktif ODTABr, vermiküler kilinin akış özelliğini değiştirmemiş ve tabakalar arası uzaklığı arttırmış veya tabakaları dağıtmıştır. Vermiküler kili, SDS ve ODTABr yüzey aktifleriyle modifiye edilerek organokil hazırlanmıştır. Hazırlanan bu organokil kullanılarak PVB polimeri ile ’’organokil/polimer nanokompoziti’’ hazırlanmıştır. Nanokompozit hazırlanırken polimerizasyon ve çözeltilerin birleştirilmesi tekniği olmak üzere iki farklı yöntem kullanılmıştır ve hangi yöntemle polimerin özelliklerinin daha çok geliştiği belirlenmeye çalışılmıştır. Hazırlanan nanokompozitlerin XRD, FTIR, TEM analizleri ile nanokompozit oldukları belirlemiştir. Ayrıca bu nanokompozitlerin termal ve mekanik özellikleri araştırılmıştır. Hazırlanan bu nanokompozitlerin XRD sonuçlarına bakıldığında, her iki yöntemde de tabakaların dağıldığı, TEM resimlerine bakıldığında ise kil parçacıklarının 100 nm boyutundan daha küçük oldukları ve kil parçacıklarının tabakalarının hem dağılmış hem de tabakalı yapılarının bir arada oldukları görülmüştür. PVB ve organokil nanokompozitlerinin orjinal PVB polimerine göre, termal dayanımları 2 kata kadar, mekanik dayanımları ise 8 kata kadar artmıştır., Recently, the studies to improve the properies of the polymers increased with increasing industrial applications of the polymers. The studies to find which addition of the nano scale particles improved the properties of polymer. The naturally layered structure of the clay is understood to be an effective addition for polymer because it can be render easily in polymer matrix. Therefore, the studies for determine the preparation methods, the characterization, and properties of the clay/polymer nanocomposites have been started. In this thesis, firstly, different type of clay samples were investigated. The interaction between clay particles analysed by rheological and electrokinetical measurements. In this study, sepiolite, montmorillonite and vermiculite clays have been used. The first aim of this study is to determine and compare the effect of the clay minerals in a clay/polymer nanocomposites concerning the mechanical and thermal properties. The effects of the different clay minerals on different polymers have been researched frequently, but the comparison of the clay minerals never studied in an article at the literature. Since, clay minerals have different properties from each other such as surface area, crystal structure, surface properties, etc., the effect of the clay minerals on the nanocomposites would be different. At first, the characterization of clay particles were investigated. Clay minerals dispersed in water and were shaked for at least 24 hours. Dispersions of clay/water were dripped on the glass layer and were waited for drying for measurment of XRD measurments. According to XRD results, montmorillonite particle’s gap between the layers were measured as 12.78 Å, for sepiolite it was found as 11.88 Å, and for vermiculite it was found as 11.33 Å. Another type of characterization is FTIR were used for investigation of bonding between particles. Also montmorillonit and vermiculite clay particles have the layered structure and sepiolite has the fiber stucture. Another type of characterization was FTIR for this samples. FTIR measurments have been done by FTIR spectrometer. Also samples were mixed with Kbr and were waited under pressure about 10 tons for preparing pellets. The results were discussed with modes of absorbance and transmittance of wave functions. In this method, the characteristic peaks of clay minerals were found. In literature, there is a lot of appliance of clay/polymer nanocomposites with different types of clays but there is not any study about comparison of which clay is more effective to improve the specific properties of polymer. Thats why our next aim was investigating which clay improves the mechanical properties of polimer in nanocomposite application. At the nanocomposite applience, layered particles are mostly preffered. Thats why montmorillonit and vermiculite clays are seems suitable for this project. Montmorillonite (Mt), vermiculite (Verm) and sepiolite (Sep) clay minerals were used to prepare the nanocomposites for the comparison. A basic polymer, polyvinyl alcohol (PVA) were chosen as the polymer and the basic method, solution-casting method was used to prepare the nanocomposites. The structural and morphological characterizations were examined by using XRD (X-ray diffraction), TEM (Transmission electron microscopy), and FTIR (Fourier transform infrared) techniques and mechanical, thermal properties of the nanocomposites were determined by DMA (Dynamical mechanical analysis) and DSC (Differential scanning calorimetry) methods. XRD results shows that, due to the exfoluation of layered clay particles which are montmorillonit and vermiculite, the characteristic peaks of clay particles were disappeared. Because of the fiber structured sepiolite particles were not exfoluated, also were flocculated in nanocomposite. In nanocomposite applications, exfoluation of layers is needed to improve the interaction between polymer and particle’s surface. Since sepiolite has not the layered structure, it is not suitable for nanocomposite applications. FTIR results showed that, there is hydrojen bonding between montmorillinite and polyvinly alcohol. According to thermal measurments, PVA polymer’s glass transition temprature (Tg) is measured as 77.2 oC. The results showed that the layered clay minerals Mt, and Verm can be dispersed well in polymer and improved the mechanical, and thermal properties more than the fibrous sepiolite. Montmorillonit addition was improved the thermal properties about 2 times, vermiculite addition was improved the mechanical properties about 6 times of polyvinly alcohol. The bigger surface area of Verm caused to the bigger values of the elastic modulus while the more interaction between Mt with PVA caused to the higher values of glass temperature. Due to bigger surface area of Verm causing to the bigger values of the elastic modulus, we prefer the Verm mineral in further experiments. According to rheological measurments, the dispertions of vermiculite in water, show the Bingam flow model and the according to electrokinetic analysis, zeta potantial measured as -17.4 mV. In the second part of the study, we modified the Verm minerals with different type of the surfactants in order to charge of the head parts of the surfactants. Vermiculite was modified with surfactants in order to enable intercalation of vermiculite layers. Since vermiculite has negative charges on its surfaces, it was expected that cationic surfactant would expand the clay layers more than an anionic surfactant. Nevertheless, OH- ions of the vermiculite surfaces were exchanged with negative parts of the anionic surfactant so unexpectedly the expansion of the layer was determined to be fully collapsed phase of vermiculite. Colloidal and structural properties of vermiculite dispersions were examined in presence of anionic, cationic and nonionic surfactants. The results showed that cationic surfactant covered the surface of the vermiculite with a second layer but the expansion of the clay layer was limited compared to the anionic surfactant. The anionic surfactant produced ion exchange with OH- ions of vermiculite and fully expanded the layer structure of the vermiculite. Also anionic and cationic surfactants didn’t changed the rheological properties of dispertions. For further experiments, we choose the octadecyl trimethylammonium bromide and sodium dodecyl sulfate. In the third part of the study, the organoclays were prepared with vermiculite; sodium dodecyl sulfate (SVerm) and octadecyl trimetylammonium bromide (OVerm). With this organoclays and polyvinyl butyral, nanocomposites were prepared. Polimerization and solution-casting methods were used in order to prepare the nanocomposites. The structural, and morphological characterizations were examined by using XRD (X-ray diffraction), TEM (Transmission electron microscopy), and FTIR (Fourier transform infrared) techniques and mechanical, and thermal properties of the nanocomposites were determined by DMA (Dynamical mechanical analysis), and DSC (Differential scanning calorimetry) methods. Organoclay samples used with PVB polymer in order to prepare nanocomposites. According to XRD (X-ray diffraction) results, organoclay particles exfolieted, and dispersed in the nanocomposites. According to TEM images, the vermiculite particle’s layers are not bigger than 100 nm. In solution-casting method, particle’s layes are nearly 100 nm, and in polymerization methods, organoclays particle’s layers are smaller than 100 nm. According to thermal analysis, the samples which prepared by solution-casting method; nanocomposites which prepared with vermiculite and SVerm, did not change the thermal properties of original PVB polymer, but the addition of OVerm to the PVB polymer increased the thermal properties. The samples which prepared by polymerization methods; nanocomposites which prepared vermiculite and SVerm increased the PVB polymer’s glass transition temprature, and addition of vermiculite and SVerm increased the melting temprature at all concentration., Yüksek Lisans, M.Sc.

Bentonite has vide variety of uses. Special use of bentonite, where its absorbing properties are employed to provide water-tight sealing is for an underground repository in granites In this paper, bentonite processing and beneficiation are described., Bentonit ima vrlo široku primjenu. Između ostalog, primjenjuje se za izradu nepropusne zaštite u podzemnim odlagalištima visoko radioaktivnog otpada u granitima zbog njegovog svojstva absorpcije vlage. U ovom radu opisuju se karakteristike i oplemenjivanje bentonita.

A comparison and estimation of usefulness of a quantitative analysis of montmorillonite in foundry bentonites, was the aim of this research. The investigations were made by means of three different techniques: methylene blue (MB) adsorption method, Cu(II)-triethylenetetramine complex (Cu(II)-TET) adsorption method, and infrared spectroscopy (FTIR) method. Tests were performed for 9 kinds of bentonites originated from various producers. The achieved results indicated that, the results obtained by the FTIR method were, in general, even 10% lower than the ones obtained by other methods. The best correlation with the data given by the producers were obtained for the Cu(II)-TET method. In addition, this method was characterised by the smallest value of standard deviations. A very essential advantage of the Cu(II)-TET method is a much shorter time needed for the analysis and its easier execution, which is important under production conditions., Cilj ovog istraživanja je bila procjena upotrebljivosti kvantitativne analize montmorilonita u ljevaoničkim bentonitima. Istraživanja su provedena pomoću tri različite tehnike: adsorpcija metilenskog modrila (MB), adsorpcija Cu(II)-trietilentetramin kompleksa (CU(II)-TET), i infracrvena spektroskopija (FTIR). Ispitivanja su provedena na 9 vrsta bentonita koji potječu od različitih proizvođača. Rezultati dobiveni FTIR metodom u prosjeku su za čak 10,0% niži od rezultata dobivenih ostalim metodama. Najbolja korelacija s podatcima od proizvođača dobivena je primjenom Cu(II)-TET metode. Osim toga, kod te metode najmanje su vrijednosti standardnih devijacija. Vrlo važna prednost Cu(II)-TET metode je znatno kraće vrijeme potrebno za anaalizu i lakše provođenje, što je značajno u proizvodnim uvjetima.

Istraživanja u okviru ovog rada su obuhvatila proučavanje mehanizma promena reoloških osobina minerala montmorilonita pri oplemenjavanju sa natrijum-karbonatom i magnezijum-hidroksi-karbonatom. Mehanizam promena reoloških osobina je izučavan na montmorilonitu 'Jelenkovac' koji je dobijen iz bentonita 'Jelenkovac', izdvajanjem čestica manjih od 2μm, sa pretežno Ca2+ i Mg2+ kao izmenljivim katjonima. Metodama strukturne analize utvrđeno je nastajanje nove faze tipa anjonske gline. Međudejstvo anjonskih i katjonskih glina dovodi do nastajanja novih struktura u obliku 'umreženih trakastih struktura' i uvršćenih po modelu 'kopče'. . The subject of this paper is the study of the montmorillonite mineral rheological characteristics change mechanism during the activation with sodium carbonate and alkali magnesium carbonate. The rheological characteristics change mechanism has been studied for the 'Jelenkovac' montmorillonite obtained from 'Jelenkovac' bentonite by separating fractions smaller than 2μm, with Ca2+ and Mg2+ mostly being the exchangeable cations. Structural analysis showed that new anionic clay type occurred. Interaction of anionic and cationic clay leads to formation of new structures called 'networked band type' connected by a 'latching' mechanism. .

Tez (Yüksek Lisans) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 2007, Thesis (M.Sc.) -- İstanbul Technical University, Institute of Science and Technology, 2007, Bu çalışmada, Türkiye’nin farklı bölgelerinden temin edilen farklı mineralojik bileşimine sahip bentonit numuneleri kullanılarak, nem alıcı (desikant) kil üretimi amaçlanmıştır. Bu bentonit numunelerinin nem adsorbe etme özelliklerinin iyileştirilmesi için çeşitli yöntem ve katkılarla bentonit numuneleri modifiye edilmiştir. Modifikasyon işlemlerinde, bentonit numuneleri üzerinde öncelikli olarak; kurutmada ısıl işlem sıcaklık ve süreleri, uygun tane boyutu tesbiti yapılmış ve ayrıca katkısız olarak yeteri kadar nem alma kapasitesine ulaşamayan bentonit numunelerine çeşitli nem alıcı kimyasal maddeler ilave edilerek nem alma kapasitesi standardlarda yer alan seviyelere getirilmiştir. Sonuçlar nem alıcı ticarı ürünlerle karşılaştırıldığında, önerilen yöntemlerle araştırma kapsamında kullanılan ve geliştirilen nem alıcı (desikant) malzemelerin ticari ürünlerin gerektirdiği spesifikasyonları sağladığı gözlenmiştir., In this study, various bentonites with different minerologies from different deposits in Turkey were subjected to tests with the aim of producing moisture adsorbents so-called desiccants of commercial grade or material competitive in the market. Bentonites used in this study were upgraded and modificated through applying several additives and methods given in the literature. In modification processes, initially the particle size, heat treatment conditions such as temperature and drying time, were examined. In addition to the standard test and parameters, chemical additives such as calcium chloride, lithium chloride and also starch which can enhance the moisture adsorption capacity were mixed with the bentonites whereby low moisture adsorption capacities of the bentonites were brought up to the levels required in the standards. The results obtained, in this study together with the standard were specifications compared with the commercial products and found to be compatible with them., Yüksek Lisans, M.Sc.

The adsorption of nicotinamide by two different Anatolian sepiolites (Eskisehir sepiolite and Bolu-Kibriscik sepiolite), loughlinite (Na-sepiolite), and palygorskite has been investigated using FT-IR spectrometry. The spectroscopic results indicate that nicotinamide molecules adsorbed on sepiolite, loughlinite and palygorskite are coordinated to surface hydroxyls and/or to Lewis acidic centers by hydrogen bonding interaction through the ring nitrogen lone pairs. Amino group nitrogen is found to be relatively in active to adsorbing sites. Some intensity and frequency changes in the OH stretching and deformation bands of surface hydroxyls (Si-OH) of the nicotinamide treated sepiolite and loughlinite were observed. But these bands are found to be less affected by the adsorption of nicotinamide in the case of palygorskite, probably because the surface Si-OH groups in palygorskite appear to be less abundant than in sepiolite or loughlinite. (c) 2004 Elsevier B.V. All rights reserved.