Academic literature on the topic 'Composite clay chemistry'
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Journal articles on the topic "Composite clay chemistry"
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Abd El-Fattah, Ahmed, and Eman Abd ElKader. "Influence of different clays on the mechanical, thermal, and water absorption properties of recycled high-density polyethylene/wood flour hybrid composites." Journal of Composite Materials 52, no. 9 (2017): 1215–26. http://dx.doi.org/10.1177/0021998317723180.
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Wood plastic composites based on recycled high-density polyethylene (r-HDPE)/wood flour with the addition of organically modified clays were prepared by melt mixing and compression molding. The effect of two different types and contents of clays, bentonite and layered double hydroxide – on the mechanical, thermal, and water absorption properties of the wood plastic composites – was examined to identify the most effective clay type for wood plastic composites. It was found that incorporation of 2 wt% modified bentonite (mBNT) clay was the most effective in the composite formulation; it has significantly enhanced the properties of the wood plastic composites. The scanning electron micrographs of the fractured surfaces showed improved interfacial adhesion of the composite components. The tensile strength of wood plastic composites was increased by 9.7% when 2 wt% mBNT clay was incorporated in the composite formulation; however, the tensile strength slightly decreased as the clay content was further increased. The izod impact strength was lowered about 10.5% by 2 wt% mBNT clay. Moreover, the addition of 2 wt% mBNT clay enhanced the water resistance of the wood plastic composites by 27.5% after immersion in water for five days. On the other hand, the modified layered double hydroxide (mLDH) clay did not cause any remarkable improvement in the properties of the wood plastic composites. The tensile strength showed a decreasing trend with an increase in mLDH content. However, both clays did not improve the thermal stability of wood plastic composites. In addition, there are no noticeable changes in the values of melting temperature by increasing the content of clays. The experimental results indicated that the properties of the wood plastic composites were significantly improved when combined with the appropriate clay type and content. However, the interaction between wood flour and the intercalated clay particles as well as the processing conditions will need further study.
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SUGAHARA, Yoshiyuki, Tomohide SUGIYAMA, Tetsuji NAGAYAMA, Kazuyuki KURODA, and Chuzo KATO. "Clay-Organic Nano-Composite." Journal of the Ceramic Society of Japan 100, no. 1160 (1992): 413–16. http://dx.doi.org/10.2109/jcersj.100.413.
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Li, Qingde, Xun Gao, Wanli Cheng, Guangping Han, and Jiye Han. "Preparation and performance of high-density polyethylene-based wood–plastic composites reinforced with red pottery clay." Journal of Reinforced Plastics and Composites 36, no. 12 (2017): 853–63. http://dx.doi.org/10.1177/0731684417693698.
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In this study, by preparing red pottery clay according to unearthed red pottery clay pieces and using red pottery clay to reinforce high-density polyethylene-based wood–plastic composites, the effects of the amount of red pottery clay on the properties of the fabricated wood–plastic composites were investigated. The results indicated that when the amount of red pottery clay increased, flexural strength and impact strength of the composite initially increased and then decreased; flexural modulus increased and tensile strength and elongation at break decreased. The cone calorimeter tests studied the effects of red pottery clay on the flame retardant and smoke suppressant behaviors of high-density polyethylene-based wood–plastic composites. Red pottery clay formed a ceramic structure on the surface and inside high-density polyethylene, thus preventing high-density polyethylene from interacting with oxygen and increasing the amount of available carbon. As a result, the flame retardant properties of wood–plastic composites were improved due to the addition of red pottery clay. A comprehensive evaluation of the properties of high-density polyethylene-based wood–plastic composites reinforced with red pottery clay showed that addition of 5% of red pottery clay resulted in the most optimal mechanical properties: the addition of red pottery clay improved the density of the composite, decreased the shrinkage rate, and enhanced the flame retardant properties.
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Jahangiri, Ali Asghar, and Yasser Rostamiyan. "Mechanical properties of nano-silica and nano-clay composites of phenol formaldehyde short carbon fibers." Journal of Composite Materials 54, no. 10 (2019): 1339–52. http://dx.doi.org/10.1177/0021998319877225.
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The mechanical properties of phenol formaldehyde (phenolic novolac) and short carbon fiber T300 polymer-based nano-composites-reinforced with nano-silica and nano-clay particles have been studied experimentally. By increasing the weight percentage of the short carbon fiber in the phenol formaldehyde, the strength of the composite increases, but its plastic deformation is severely limited. Also, in the case of composite reinforced with nano-silica particles, the tensile and flexural strength of the composite with the increase in the weight percentage of the nano-silica increase by 1% to 3%, whereas with the nano-clay particles, the tensile and flexural strength of the composite decrease by 1% to 3%. It is composite with 1% weight percentage of the nano-clay particle which has the highest strength in comparison to the other samples. Regardless of the type of corrosive solution, the composite strength decreases significantly over 25 days. However, with an increase in the duration from 25 days to 45 days, a slight change has been observed. The outcomes indicate that the corrosion of PF/CF40% composites and the composite reinforced with silica nanoparticles are higher corrosion rate in acid than in salt solution. In contrast, the nano-clay composite has more corrosion in salt solution. Furthermore, the analysis of the fracture surface of samples done by SEM microscopy shows reduction of the porosity in the case of using nanoparticles.
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Muthu, Jacob, Janet Priscilla, Akindele Odeshi, and Nalen Kuppen. "Characterisation of coir fibre hybrid composites reinforced with clay particles and glass spheres." Journal of Composite Materials 52, no. 5 (2017): 593–607. http://dx.doi.org/10.1177/0021998317712568.
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Hybrid composite materials were fabricated using an optimum coir fibre with functionalised clay and glass spheres using a vacuum-assisted resin transfer moulding. The coir fibres were treated with 10% sodium hydroxide (NaOH) to improve their bonding properties by removing the cellulose and lignin found on the fibre surface. Clay functionalisation was done using 3-aminopropyltriethoxysilane at different ratios and obtained an optimum ratio of 1 g clay: 2 g silane. Composite specimens were fabricated using epoxy and coir fibre at 7%, 10%, 15% and 20% volume fractions, respectively. Based on the mechanical properties, an optimum volume fraction of 15% coir fibre was selected to fabricate the hybrid composites with functionalised clay and glass spheres reinforcements, respectively. These composite specimens were then characterised to obtain their tensile, flexural and impact properties. From the results, it was realised that hybrid composites containing 4% functionalised clay particles and 8% glass spheres have superior mechanical properties. The reason behind the improved properties might be due to the reinforcing effect of the particles, which improved the load transfer between the fibre and the matrix.
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del Pino, Gilberto García, Abderrezak Bezazi, Haithem Boumediri, et al. "Hybrid epoxy composites made from treated curauá fibres and organophilic clay." Journal of Composite Materials 55, no. 1 (2020): 57–69. http://dx.doi.org/10.1177/0021998320945785.
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This work evaluates an epoxy composite reinforced with curauá fibres and/or organophilic clay. Epoxy polymers reinforced with nano-clays are also assessed. Composites are manufactured by cold pressing using fibres in pristine and treated conditions. Three levels of the factors NaOH solution (2.5, 5 and 10%) and immersion time (2, 4 and 10 hours) are investigated. Nano-clays are incorporated at the levels of 2.5, 5 and 10 wt.%. The morphology and crystallinity of the treated fibres are evaluated by scanning electron microscopy and X-ray diffraction, respectively. Tensile, three-point bending and impact tests are performed to characterise the composites. Tensile strength, flexural strength and impact resistance are increased by 24%, 44% and 47%, respectively, when compared to untreated fibre composites. The highest tensile and flexural strengths are achieved by hybrid composites containing 5 wt.% of nano-clay and 20 wt.% of curauá fibres treated with 5% NaOH for 4 hours. In contrast, the highest tensile modulus is achieved when hybrid composites are made from untreated fibres and 10 wt.% of nanoparticles. The highest impact resistance is obtained by curauá composites, without particles, composed of fibres treated with 5% NaOH for 4 hours. The inclusion of nano-clay leads to reduced impact resistance values.
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Zhumagaliyeva, Sh N., R. S. Iminovа, G. Zh Kairalapova, B. M. Kudaybergenova, and Zh A. Abilov. "Sorption of Heavy Metal Ions by Composite Materials Based on Polycarboxylic Acids and Bentonite Clay." Eurasian Chemico-Technological Journal 23, no. 1 (2021): 19. http://dx.doi.org/10.18321/ectj1030.
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The paper shows the study results of sorption capacities of composite gels based on polyacrylic and polymethacrylic acids with bentonite clay as the mineral filler concerning heavy metal ions (Pb+2, Cu+2, Ni+2, Zn+2, Fe+2, Cd+2). The binding of metal ions to gels occurs through the formation of electrostatic bonds between the charged surface of bentonite clay and ionogenic functional groups of polymers in the composition, as well as the coordination bonds between metal ions and unshared pairs of oxygen electrons in the functional groups of polymers. The gel swelling degree decreases in metal solutions with increasing metals concentration and the content of BC in the composite. The sorption and desorption of heavy metal ions from the polymer-clay composites from model solutions and samples of industrial wastewater from the Kazakhstani metallurgical plants were evaluated. The adjustment of the pH, the temperature of the medium and the clay content in the composite leads to increasing the degree of sorption and achieving regeneration of the used composite gels in certain media. The data obtained testify to the prospects of using these composites as effective sorbents of heavy metals from industrial wastewaters expanding the range of composite materials for wastewater treatment.
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Binitha, N. Narayanan, and Sankaran Sugunan. "Polyaniline/pillared montmorillonite clay composite nanofibers." Journal of Applied Polymer Science 107, no. 5 (2007): 3367–72. http://dx.doi.org/10.1002/app.27353.
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Huebner, Henry J., and Timothy D. Phillips. "Clay-Based Affinity Probes for Selective Cleanup and Determination of Aflatoxin B1 Using Nanostructured Montmorillonite on Quartz." Journal of AOAC INTERNATIONAL 86, no. 3 (2003): 534–39. http://dx.doi.org/10.1093/jaoac/86.3.534.
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Abstract A study was conducted to investigate the selective cleanup and determination of aflatoxin B1 (AfB1) from contaminated media. Composite adsorbents were formulated from calcium montmorillonite clay, which possesses a high affinity and enthalpy of adsorption for AfB1. Nanostructuring techniques were used to construct various formulations of the clay-based composite media. In AfB1 adsorption studies with prototypical affinity columns, these composites offered narrowly defined, reproducible capacity ranges. Composite recoveries of AfB1 from spiked grains exhibited linear trends that correlated well with the range of spike levels. Composite columns provided lower recoveries of AfB1 from naturally contaminated corn than did immunoaffinity columns; however, recoveries were consistent and purified extracts were free of inter-fering compounds, as determined by liquid chro-matography with fluorescence detection.
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Liu, Pengfei, Mingyong Du, Peta Clode, Jishan Liu, and Yee-Kwong Leong. "Rod–plate interactions in sepiolite–LAPONITE® gels: microstructure, surface chemistry and rheology." Soft Matter 17, no. 9 (2021): 2614–23. http://dx.doi.org/10.1039/d0sm02112a.
Full textDissertations / Theses on the topic "Composite clay chemistry"
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Lao, Hongbai. "Novel microporous organo-clay materials and organo-clay polymeric composite membranes." Thesis, University of Ottawa (Canada), 1993. http://hdl.handle.net/10393/6830.
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A series of quaternarized ammonium mono and di-cations, quaternarized amino acid ester mono and di-cations, and quaternarized polyammonium cations were synthesized by methylation reaction. The synthesized quaternarized ammonium derivatives were incorporated into the interlamellar space of the smectites, montmorillonite (SWy-1) and hectorite (SHCa-1). The adsorption of these quaternarized ammonium cations by the smectites were studied by colorimetric and Na-electrode methods. Also the CEC values were determined from the adsorption isotherms and were found to be close to the CECs of the smectites. The intercalation of the quaternarized ammonium cations into the interlamellar space of the smectites were evaluated by X-ray powder diffraction technique and the changes of the interlayer spacings upon intercalation were measured. The adsorption and X-ray results indicated that the quaternarized ammonium cations adopt a parallel orientation arrangement in the interlamellar space of the smectites. Insight into the micropore structure of the prepared organo-smectites has been obtained with N$\sb2$ adsorption and desorption studies. The BET interlayer surface area, external surface area, micropore volume and mesopore volume were calculated from the N$\sb2$ adsorption and desorption isotherms. The total BET surface areas of the organo-smectites were in the range of 58-224 m$\sp2$/g, depending on the size of the intercalated cations. It has been implied that the incorporation of the quaternarized ammonium cations into the interlamellar space of the smectites results in a microporous material with a network of cavities whose height and volume are controlled by the size and the shape of the organic cation. The gas chromatographic properties of these organo-smectites have been determined with focus on the separation of air, CH$\sb4$ and CO$\sb2$ as well as the separation of C$\sb1$-C$\sb4$ and C$\sb5$-C$\sb8$ hydrocarbons. The organo-smectites have been proven to be a GC adsorbent for gas separations. The separation of methane and carbon dioxide was controlled by the interactions with the clay surface, not by the interaction with the substituents of the alkylammonium chain. The shapes of the microcavities played a role in the separation of gas mixtures. The CO$\sb2$ retention time has been found to increase with increasing the free surface area of the organo-smectite. Moreover, it has been shown that the retention time of C$\sb1$-C$\sb4$ hydrocarbons decreased with increasing the free volume of the organo-smectite. Furthermore, some microporous organo-smectite materials have been imbedded into the cross-linked polydimethylsiloxane (PDMS) polymers giving composite membranes. The composite membranes have been evaluated by the gas permeation experiments. The pure gas permeation results showed that the gas permeabilities decreased upon filling of the organo-smectites into the PDMS polymers. The pure gas permeability ratios of O$\sb2$/N$\sb2$ and CO$\sb2$/CH$\sb4$ were found to be controlled by both the organo-smectite content and the microporosity of the organo-smectites. The maximum pure gas permeability ratio for CO$\sb2$/CH$\sb4$ achieved was 8.7 as compared to 3.9 which was obtained for organo-smectite free PDMS membranes.
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Tudor, Jonathan Simon. "Synthesis and catalytic activity of organometallic-inorganic composite materials." Thesis, University of Oxford, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.339188.
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Zhang, Yongcheng. "Part I. Natural fiber / thermoplastic composites Part II. Studies of organo-clay synthesis and clay intercalation by epoxy resins /." Diss., Mississippi State : Mississippi State University, 2008. http://library.msstate.edu/etd/show.asp?etd=etd-11032008-094748.
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Samakande, Austin. "Use of the RAFT technique as an efficient method to synthesise well defined polymer-clay nanocomposites with improved properties." Thesis, Stellenbosch : University of Stellenbosch, 2009. http://hdl.handle.net/10019.1/1242.
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Thesis (PhD (Chemistry and Polymer Science))--University of Stellenbosch, 2009.<br>Synthesis and structural characterization of two novel cationic and three new neutral
reversible addition–fragmentation chain transfer (RAFT) agents is described. The
cationic RAFT agents bear a quaternary ammonium group: N,N-dimethyl-N-(4-
(((phenylcarbonothionyl)thio)methyl)benzyl)ethanammonium bromide (PCDBAB) and
N-(4-((((dodecylthio)carbonothioyl)thio)methyl)benzyl)-N,N-dimethylethanammonium
bromide (DCTBAB). The three neutral RAFT agents synthesized are 1,4-
phenylenebis(methylene)dibenzene carbodithioate (PCDBDCP), didodecyl-1,4-
phenylenebis(methyllene)bistrithiocarbonate (DCTBTCD) and 11-(((benzylthio)carbonothioyl)
thio)undecanoic acid (BCTUA). The self-assembly behaviour in diluted
aqueous solutions of the cationic RAFT agents, PCDBAB and DCTBAB, is
described. The self-assembly behaviour was promoted by the presence of the thiocarbonyl-
thio group on the RAFT agents, in addition to the overall chemical structure
of the surfactant that also influence self-assembly.
The RAFT agents were used for the bulk or miniemulsion RAFT-mediated controlled
free-radical polymerization in the presence of clay to yield polymer–clay
nanocomposites (PCNs). Bulk polymerization resulted in PCNs with better control of
molar mass and polydispersity index (PDI) values when compared to PCNs prepared
by miniemulsion polymerization. In both bulk and miniemulsion polymerizations the
molar masses and PDI values were dependent on the amount of clay and RAFT
agent present in the system.
Free-radical bulk neutral RAFT agent-mediated polymerization resulted in PCNs with
predominantly intercalated morphology. This was attributed to radical–radical
coupling of the initiator anchored onto the clay galleries on which polymerization took
place. On the other hand, when the cationic RAFT agent anchored onto clay, i.e.
RAFT-modified clay was used, bulk polymerization resulted in predominantly exfoliated PCNs. However, miniemulsion polymerization carried out in the presence
of the RAFT-modified clays resulted in PCNs with a morphology that ranged from
partially exfoliated to intercalated morphology, as the clay loading was increased.
The changing morphology for miniemulsion-based PCNs was attributed to the
decreasing molar mass as the clay loading was increased.
The PCNs obtained had enhanced thermo-mechanical properties as a result of the
presence of clay. The thermo-mechanical properties depended on the molar mass,
PDI, clay loading, and the morphology of the PCNs.
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Zengeni, Eddson. "Highly filled water based polymer/clay hybrid latexes." Thesis, Stellenbosch : Stellenbosch University, 2012. http://hdl.handle.net/10019.1/71613.
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Thesis (PhD)--Stellenbosch University, 2012.<br>ENGLISH ABSTRACT: The use of co-sonication (ad-miniemulsion) polymerisation for the preparation of highly filled polymer/clay hybrid latexes is described. Laponite (Lap) content levels in the range of 10–50 wt% were effectively encapsulated in both polystyrene (PS) and polystyrene-co-butyl acrylate nanoparticles (PSBA). The latex and film morphological features of these highly filled hybrid materials were evaluated using both transmission electron microscopy (TEM) and small angle X-ray scattering (SAXS). PS/Lap latexes exhibited mixed particle morphologies from armoured particles at low clay content (10 wt%) to encapsulated particles at high clay content (50 wt%). However, PSBA/Lap hybrid latexes exhibited predominantly crumpled particle morphologies through the clay content studied. The resultant polymer/clay nanocomposites (PCNs) of PS/Lap and PSBA/Lap exhibited either partially or fully exfoliated structures. It was found that generally these PCNs exhibited superior properties than the neat polymers except for thermal stability properties. As much as 5000% storage modulus improvement was observed for both PS/Lap and PSBA/Lap relative to the neat polymers. The Tg of PSBA/Lap showed a 14 ºC shift towards higher temperature. Rheology tests showed that the resultant PCNs exhibited solid-like viscoelastic behaviour. The encapsulation of montmorilonite clay (MMT) using the ad-miniemulsion procedure was found to be ineffective. The MMT platelets remained adhered onto the polymer particles surfaces. Ineffective encapsulation of MMT platelets was attributed to their dimensions which were either large or equal to those of the polymer particles. Despite the ineffective encapsulation, the MMT platelets were completely exfoliated within the final PCNs as shown by both SAXS and TEM.
Overall, the ad-miniemulsion was found to be an effective method for the preparation of highly filled water based polymer/clay hybrid latexes. However, the clay encapsulation in polymer particles and the extent of clay exfoliation were found to be dependent on clay dimensions relative to the polymer particles, monomer/clay compatibility and clay modifier reactivity. It was found that clay dimensions and use of clay modifier that improve monomer/clay compatibility enhances encapsulation. On the other hand, the modifier reactivity influenced the extent of clay exfoliation in the final PCN, irrespective of clay encapsulation in the polymer particles. These findings were based on comparative studies conducted on the use of Lap versus MMT and non-reactive modifier versus reactive modifier during ad-miniemulsion polymerisation.<br>AFRIKAANSE OPSOMMING: Die gebruik van mede-sonikasie (ad-miniemulsie) polimerisasie vir die voorbereiding van die hoogsgevulde polimeer/klei hibriedlatekse word beskryf. Laponiet (Lap) vlakke in hoeveelhede van 10-50 gew% is effektief ge-inkapsuleer in beide polistireen (PS) en polistireen-ko-butielakrilaat nanopartikels (PSBA). Die morfologiese eienskappe van die latekse en films van hierdie hoogsgevulde hibried materiale is geëvalueer deur beide transmissie-elektronmikroskopie (TEM) en klein-hoek X-straal-verstrooiing (SAXS). PS/Lap latekse het gemengde partikel morfologieë getoon, bv. vanaf gepantserde partikels by lae kleihoeveelhede (10 gew%) tot ge-inkapsuleerde partikels by hoë kleihoeveelhede (50 gew%). Daarteenoor het PSBA/Lap hibriedlatekse „n oorwegend verkreukelde partikelmorfologie getoon vir die reeks kleihoeveelhede wat bestudeer is. Die gevolglike polimeer/klei nanokomposiete (PKNs) van PS/Lap en PSBA/Lap het, óf gedeeltelike, óof ten volle geëksfolieerde strukture getoon. Oor die algemeen is bevind dat hierdie PKNs beter eienskappe as die suiwer polimere getoon het, behalwe vir die termiese stabiliteit eienskappe. Verbeteringe van soveel as 5000% in die stoormodulus is waargeneem vir beide PS/Lap en PSBA/Lap met betrekking tot die suiwer polimere. Die Tg van PSBA/Lap het „n 14°C verskuiwing na „n hoër temperatuur getoon. Reologiese toetse het getoon dat die gevolglike PKNs vastestofagtige visko-elastiese gedrag getoon het. Die inkapsulering van montmorilonietklei (MMT), deur middel van die ad-miniemulsieproses, was ondoeltreffend. Die MMT plaatjies het agtergebly op die oppervlaktes van die polimeerpartikel. Oneffektiewe inkapsulering van MMT plaatjies is toegeskryf aan hul grootte, wat óf groter, óf gelyk was aan dié van die polimeerpartikels. Ten spyte van die oneffektiewe inkapsulering was al die MMT plaatjies in die finale PKNs geëksfolieer soos deur beide SAXS en TEM aangedui.
Oor die algemeen is bevind dat ad-miniemulsie „n effektiewe metode is vir die voorbereiding van hoogsgevulde waterbasis polimeer/klei hibriedlatekse. Daar is egter bevind dat klei inkapsulering in polimeerpartikels asook die omvang van klei eksfoliëring, afhanklik is van die klei afmetings in verhouding tot die polimeerpartikels, monomeer/klei verenigbaarheid en die reaktiwiteit van die kleiwysiger. Daar is bevind dat die klei afmetings en die gebruik van „n kleiwysiger wat die monomeer/klei verenigbaarheid verbeter, inkapsulering bevorder. Aan die ander kant het die reaktiwiteit van die kleiwysiger die omvang van klei eksfoliëring in die finale PKNs beïnvloed, ongeag van klei inkapsulering in die polimeerpartikels. Hierdie bevindings is gebaseer op vergelykende studies van die gebruik van Lap teenoor MMT en nie-reaktiewe wysiger teenoor reaktiewe wysiger gedurende ad-miniemulsiepolimerisasie.
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Chirowodza, Helen. "Polymer-clay nanocomposites prepared by RAFT-supported grafting." Thesis, Stellenbosch : Stellenbosch University, 2012. http://hdl.handle.net/10019.1/71914.
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Thesis (PhD)--Stellenbosch University, 2012.<br>ENGLISH ABSTRACT: In materials chemistry, surface-initiated reversible deactivation radical polymerisation (SI-RDRP) has emerged as one of the most versatile routes to synthesising inorganic/organic hybrid materials consisting of well-defined polymers. The resultant materials often exhibit a remarkable improvement in bulk material properties even after the addition of very small amounts of inorganic modifiers like clay.
A novel cationic reversible addition–fragmentation chain transfer (RAFT) agent with the dual purpose of modifying the surface of Laponite clay and controlling the polymerisation of monomer therefrom, was designed and synthesised. Its efficiency to control the polymerisation of styrene was evaluated and confirmed through investigating the molar mass evolution and chain-end functionality.
The surface of Laponite clay was modified with the cationic chain transfer agent (CTA) via ion exchange and polymerisation performed in the presence of a free non-functionalised CTA. The addition of the non-functionalised CTA gave an evenly distributed CTA concentration and allowed the simultaneous growth of surface-attached and free polystyrene (PS). Further analysis of the free and grafted PS using analytical techniques developed and published during the course of this study, indicated that the free and grafted PS chains were undergoing different polymerisation mechanisms. For the second monomer system investigated n-butyl acrylate, it was apparent that the molar mass targeted and the monomer conversions attained had a significant influence on the simultaneous growth of the free and grafted polymer chains. Additional analysis of the grafted polymer chains indicated that secondary reactions dominated in the polymerisation of the surface-attached polymer chains.
A new approach to separating the inorganic/organic hybrid materials into their various components using asymmetrical flow field-flow fractionation (AF4) was described. The results obtained not only gave an indication of the success of the in situ polymerisation reaction, but also provided information on the morphology of the material.
Thermogravimetric analysis (TGA) was carried out on the polymer-clay nanocomposite samples. The results showed that by adding as little as 3 wt-% of clay to the polymer matrix, there was a remarkable improvement in the thermal stability.<br>AFRIKAANSE OPSOMMING: Oppervlakgeïnisieerde omkeerbare deaktiveringsradikaalpolimerisasie (SI-RDRP) is een van die veelsydigste roetes om anorganiese/organiese hibriedmateriale (wat bestaan uit goed-gedefinieerde polimere) te sintetiseer. Die produk toon dikwels ʼn merkwaardige verbetering in die makroskopiese eienskappe – selfs na die toevoeging van klein hoeveelhede anorganiese modifiseerders soos klei.
ʼn Nuwe kationiese omkeerbare addisie-fragmentasie kettingoordrag (RAFT) middel met die tweeledige doel om die modifisering van die oppervlak van Laponite klei en die beheer van die polimerisasie van die monomeer daarvan, is ontwerp en gesintetiseer. Die klei se doeltreffendheid om die polimerisasie van stireen te beheer is geëvalueer en bevestig deur die molêre massa en die funksionele groepe aan die einde van die ketting te ondersoek.
Die oppervlak van Laponite klei is gemodifiseer met die kationiese kettingoordragmiddel (CTA) deur middel van ioonuitruiling en polimerisasie wat uitgevoer word in die teenwoordigheid van ʼn vrye nie-gefunksionaliseerde CTA. Die toevoeging van die nie-gefunksionaliseerde CTA het ʼn eweredig-verspreide konsentrasie CTA teweeggebring en die gelyktydige groei van oppervlak-gebonde en vry polistireen (PS) toegelaat. Verdere ontleding van die vrye- en geënte PS met behulp van analitiese tegnieke wat ontwikkel en gepubliseer is gedurende die verloop van hierdie studie, het aangedui dat die vry- en geënte PS-kettings verskillende polimerisasiemeganismes ondergaan. n-Butielakrilaat is in die tweede monomeer-stelsel ondersoek en dit was duidelik dat die molêre massa wat geteiken is en die geënte polimeerkettings.
ʼn Nuwe benadering tot die skeiding van die anorganiese/organiese hibriedmateriale in hulle onderskeie komponente met behulp van asimmetriese vloeiveld-vloei fraksionering (AF4) is beskryf. Die resultate wat verkry is, het nie net 'n aanduiding gegee van die sukses van die in-situ polimerisasiereaksie nie, maar het ook inligting verskaf oor die morfologie van die materiaal. Termogravimetriese analise (TGA) is uitgevoer op die polimeer-klei nanosaamgestelde monsters. Die resultate het getoon dat daar 'n merkwaardige verbetering in die termiese stabiliteit was na die toevoeging van so min as 3 wt% klei by die polimeermatriks.
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VU, YEN THI. "SYNTHESIS AND CHARACTERIZATION OF ELASTOMER-BASED COMPOSITES AND POLYMER-IMMOBILIZED COLLOIDAL TRANSITION METAL NANOPARTICLES: CATALYTIC SELECTIVITY AND MORPHOLOGY." University of Cincinnati / OhioLINK, 2001. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1004541836.
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Huang, Gang. "CHARACTERIZATION AND PROPERTY STUDIES OF CYANATE ESTER/ORGANOCLAY NOCOMPOSITES." MSSTATE, 2006. http://sun.library.msstate.edu/ETD-db/theses/available/etd-07072006-162122/.
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Five series of PT-30/organoclay (Cloisite 10A, Cloisite 30B, Nanomer I.28E, Nanomer I.30E and Nanomer I.44PA) composites were prepared and characterized. The dispersion of clay tactoids in PT-30 resin was studied by XRD and TEM. XRD analyses determined that the d-spacings of each nanoclays of these were expanded upon dispersing in the PT-30 matrix versus the as-received clay. TEM micrographs further demonstrated that the intercalation of clay layers by PT-30 occurred during the curing process. Histograms of clay tactoids distributions were generated based on the combination of XRD and TEM results. The glass transition temperatures (Tg) of selected PT-30/clay composites were measured by DSC and compared. Partial clay exfoliation with some resin intercalation was demonstrated. The average flexural strengths and flexural moduli of all composites were obtained using three-point bending tests.
Book chapters on the topic "Composite clay chemistry"
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Hızal, Jülide, and Mesut Yılmazoğlu. "Montmorillonite Clay Composite for Heavy Metal Removal from Water." In Environmental Chemistry for a Sustainable World. Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-47400-3_4.
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İsmail Tosun, Yıldırım. "Adsorption of Heavy Metals by Microwave Activated Shale/Asphaltite Char/Zeolite Granule Composts from Hazardous Sludges and Industrial Waste Slurries." In Clay Science and Technology [Working Title]. IntechOpen, 2020. http://dx.doi.org/10.5772/intechopen.94404.
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There is a great concern about surface water pollution with high level mercury, lead (Pb) over 10 mg/l, 30 mg/l to the fishing lakes and streams in Şırnak Province even contaminating fresh water fishing and poisonening of human by merury and lead in thr region. The chromium over 50 mg/l from industrial seepages was disposed to lakes and streams in our country. There is a great green concern prompting land in order to control acidic mine waters so that the research study controlled and avoided hazardous metal limits of residual stream contaminants of heavy metals by sorption local clay and zeolite compost. The contamination rate changes to those based on seepage concentrations and wetness. The stream amendments, such as shale char carbonized from Şırnak asphaltite containing 52–60% shale activated by acid washing under microwave radiation as geo material composted for waste water treatment should control contaminated effluents concentration. The field studies to evaluate the stability of heavy metal concentrations and salts were scarce. The initial objective of this study was to determine the effects of seepage flow to surface and groundwater from the industrial discharge. In this study, important investigations have been made on composite granules production with Şırnak shale char and zeolite feed in order to activated in microwave oven 2 M HCl dissolution. The compost sorbent for high level heavy metal sorption in laboratory water packed bed column adsorption compost system. However, the results of filled packed bed zeolite yield high metal transfer to compost. Due to the complex chemistry of shale pores, and high porosity, heat conduction improved in the microwave sorption depended on granule size decreased. The other heavy metal sorption distribution was changed in the activation dependent on the microwave heating power.
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Sonkaria, Sanjiv, and Hyun Joong Kim. "Nanoscale Configuration of Clay-Interlayer Chemistry: A Precursor to Enhancing Flame Retardant Properties." In Flame Retardant and Thermally Insulating Polymers. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.95788.
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Nanomaterials are proving to be pivotal to the evolution of controllable, cost-effective and environmentally safe technologies. An important concern is the impact of low-dimensional compositional materials and their ability to significantly reduce the hazardous nature of flame retardants that are reputably harmful through unchecked inhalation. While eco-friendly and recyclable alternatives are necessary requirements to function as replacements for the ‘Next Generation’ of flame retardants, the underlying ‘Chemistry’ at the nanoscale is unfolding unlocking vital clues enabling the development of more effective retardants. In this direction, the dimensional order of particles in naturally occurring nanoclay materials and their associated properties as composites are gaining increasing attention as important constituents of flame retardants. In this review, we examine closer the compositional importance of intercalated/exfoliated nanoclay networks essential to retardant functionality exploring the chemical significance and discussing underlying mechanisms where possible.
Conference papers on the topic "Composite clay chemistry"
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Burlakovs, Juris, Jovita Pilecka, Inga Grinfelde, and Ruta Ozola-Davidane. "Clay minerals and humic substances as landfill closure covering material constituents: first studies." In Research for Rural Development 2020. Latvia University of Life Sciences and Technologies, 2020. http://dx.doi.org/10.22616/rrd.26.2020.032.
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Soil and groundwater as the leachate may contaminate surrounding watersheds, thus different pollutants from closed dumps and landfills pose significant risks to human health and ecology. Pollution may lead to soil and water degradation however it might be diminished through sustainable dump site closure projects and processual management. Several decades of clays and clay minerals studies lead to modified clay composites concept that is one of the potential promising solutions for building the landfill covering material and serve as capping biocover layer at the same time. As humic substances are constituents of soil organic matter, pollutants can be sorbed on the surfaces of complex molecules. This kind of humic acid-clay mineral composite materials thus might become as low cost building material component - covering material. Construction of such layer are to be performed as a combination of clay-humic composites and landfill mined fine fraction of waste with small amendment of natural soil. Several hypotheses that are already proven has to be mentioned: a) Clay minerals produce composites with humic substances; 2) Clay-humic complexes reduce through sorption both organic and inorganic pollutants; 3) Low risk of toxic byproducts from landfill mined waste fine fraction can be the problem; 4) Such composites mostly would trap toxic contaminants (e.g., pharmaceuticals) found in reworked fine fraction of waste. The aim of the work is to provide alternative solution for landfill closure by giving theoretical considerations from multidisciplinary knowledge of environmental engineering, chemistry and waste management.
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Zheng, Hongjuan, and Zhengqian Sun. "Preparation and Properties of PLA/clay composites." In 2016 5th International Conference on Environment, Materials, Chemistry and Power Electronics. Atlantis Press, 2016. http://dx.doi.org/10.2991/emcpe-16.2016.149.
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