Modification Of MMT Research Articles

Impact resistance of polyurethane elastomer enhanced by organic montmorillonite with interlayer anchored polymer chains

AbstractThe development of materials with excellent impact resistance is essential for safety protection. Polyurethane elastomer (PUE) is widely used in impact protection; however, it has low dynamic compressive strength and poor energy absorption efficiency under high‐speed impact, limiting its in‐depth application in the protection field. Herein, an organic montmorillonite (MMT) with interlayer anchored polymer chains, named M@NH3+, was synthesized via the dual modification of MMT involving surface grafting and cation intercalation by macromolecular amino silane, which was used to enhance the impact resistance of PUE. Based on the uniform dispersion of M@NH3+ within the PUE matrix, the strong bonding at the polymer‐filler interface and the synergistic action between M@NH3+ lamellae, PUE‐M@NH3+ composite exhibited excellent mechanical properties and energy absorption capacity. Compared with pure PUE, the elastic modulus (+98.3%), static compressive strength (+37.0%), dynamic compressive strength (+35.4%) and impact energy absorption (+50.8%) of PUE‐2wt%M@NH3+ were significantly improved, which shows that it has potential applications in the field of high‐speed impact protection.Highlights Organic MMT with interlayer anchored polymer chains was prepared. The large interlayer spacing of M@NH3+ facilitates its dispersion within the matrix. The interconnected M@NH3+ lamellae can collaboratively disperse impact stress. The impact energy absorption of PUE composite has been remarkably improved.

Enhanced fluoride removal using montmorillonite clay modified with CoFe2O4 and metal-organic frameworks

The use of modified clays can play an effective role as an effective adsorbent in removing fluoride (Flu) ions from water and aqueous solutions. In the present research, montmorillonite clay (MMt) was modified using CoFe2O4 magnetic particles and Al–Fe fumarate metal-organic framework (Al–Fe Fum) and was utilized as an efficient adsorbent for removing Flu from aqueous solution. The properties of MMt and MMt/CoFe2O4/Al–Fe Fum samples were investigated using different techniques. The results showed that with the modification of MMt using CoFe2O4 magnetic particles and the metal-organic framework of Al–Fe Fum, the BET surface has increased notably from 13.217 to 365.80 m2/g. To investigate the effect of independent variables and their interaction on the efficiency of the Flu adsorption, response surface method-central compound design (RSM-CCD) was served. Based on the results of ANOVA, the F-value and p-value parameters for the desired model were determined to be 783.09 and < 0.0001, respectively, which confirms the success and high ability of the model. The number of R2, adjusted R2, and Predicted R2 for adsorption of Flu ion was determined to be 0.998, 0.997, and 0.995, respectively, which shows that the proposed regression model can describe the process of adsorption and interaction between variables well. Compared to other kinetic models, the pseudo 2nd order kinetic model has a greater ability to describe the Flu adsorption behavior. The R2 parameter value determined that the Freundlich isotherm model has a suitable ability to investigate the isotherm behavior and confirms the effect of heterogeneous surfaces in the process. Generally, the outcomes signified that the MMt and MMt/CoFe2O4/Al–Fe Fum samples can be reused several times in the process of Flu adsorption, while the efficiency is more than 90%.

Preparation and Corrosion Resistance of OMMT/EP Composite Coatings in Sulfur-Containing Sodium Aluminate Solution

Organic montmorillonite (OMMT) was prepared from Na-montmorillonite (MMT) by Hexadecylamine (HDA) modification. The composite material has good smoothness, acidity, and salt resistance. OMMT was characterized using small-angle X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and a video optical contact angle measuring instrument. The results showed that the layer spacing was enlarged from 1.44 nm to 2.87 nm after the modification, and the hydrophobicity performance was greatly improved. The organic modification of MMT was successful. The surface morphology, roughness, and anticorrosion properties of the organic montmorillonite/epoxy (OMMT/EP) composite coating were investigated and compared with those of the epoxy (EP) coating. The OMMT/EP composite coating had a flatter surface than the EP coating. The roughness was reduced from 65.5 nm to 10.3 nm. The electrochemical impedance spectroscopy showed that the composite coating’s thickness positively affected its anticorrosion performance, the corrosion current density (Icorr) decreased with the increase in thickness, and its maximum impedance was much larger than that of EP coating. The protection efficiency of the OMMT/EP composite coating was 77.90%, which is a significant improvement over the EP’s 31.27%. In addition, the corrosion resistance of the composite coating gradually decreased with increasing immersion time, but the change was insignificant.

Synthesis and characterization of rigid water-blown, palm oil-based polyurethane/organically-modified clay nanocomposite foam

Despite the superior enhancement it could impose, incorporation of montmorllonite (MMT) nanoclay in polymer-matrix composites is still limited due to miscibility issues with its host matrix; which could be alleviated with surface-modification of the nanoclay. In this paper, diamino methylpentane-modified montmorillonite (DAMP-MMT) nanoclay was incorporated into a bio-based polyurethane (PU) foam at different weight loadings. Characterization tests were then carried out to investigate the influence of included organoclay on the mechanical properties, thermal stability, foam morphology, and foaming kinetics. MMT modification effect could clearly be observed with exfoliated microstructure at lower loadings, compared to pristine clay at similar loading. Presence of organic modifier tethered on the surface of nanoclay was found to act as catalyst which induced accelerated curing, affecting cellular size and structure of foam, which in return cascades into influencing mechanical and thermal properties of the foam. Compressive strength improved with addition of 1 wt.% clay, and deteriorated beyond this point; believed due to clay agglomeration at higher clay loadings. However, thermal stability showed improvement parallel with its clay content, believed owed to additional bonds formed between amine -NH2 from organoclay and – NCO from diisocyanates. Incorporation of organoclays in rigid bio-based PU foam shows great potential in moderate load-bearing applications while upholding “green chemistry” practice.

A novel alkylpolyglucoside‐modified montmorillonite‐filled starch bionanocomposites produced by extrusion

AbstractNative cassava starch was modified by dry heating treatment, and sodic montmorillonite was modified using an alkylpolyglucoside biosurfactant to produce a novel montmorillonite‐filled starch bionanocomposites with improved performance. The bionanocomposites were produced in two extrusion steps using a co‐rotating twin‐screw extruder. The structural properties of the bionanocomposites were studied by X‐ray diffraction. The reinforcement effect and material performance were evaluated by hydrophobicity, solubility, opacity, barrier, thermal and mechanical properties. In general, the dispersion of the nanofillers resulted in bionanocomposites with intercalated structures and improved properties compared with unfilled bioplastics. The main results exhibited that modified montmorillonite showed better compatibility with starch, improving nanofiller dispersion and interaction than the native one. As a result, it increased the hydrophobicity and reduced solubility, water, and oxygen permeabilities in comparison with bionanocomposites based on native starch by 36%, 48%, and 68%, respectively. Also, the tensile strength and Young modulus increased from 0.60 to 2.56 MPa and from 2.99 to 15.68 MPa, respectively. In conclusion, modification of MMT by the biosurfactant is a good approach to enhance dispersion/interaction with the starch matrix.

Preparation of solvent-resistant polyimide membranes for efficient separation of dyes and salts via an “internal drive” strategy

It is extremely difficult to separate salts and dyes from high-salinity printing and dyeing wastewater. In this study, modified montmorillonite (EPTAC-CD-MMT) was obtained by intercalation of 2,3-epoxypropyltrimethylammonium chloride (EPTAC) modified cyclodextrin (CD). PI/EPTAC-CD-MMT membrane was prepared by blending EPTAC-CD-MMT with polyimide (PI). The addition of EPTAC-CD-MMT could inhibit the motion of PI molecular chains and increase the solvent resistance of the membrane. Additionally, EPTAC-CD-MMT exhibited spontaneous “internal drive” during the phase transition and segregated to the membrane surface. The pore structure of the membrane was adjusted to a well-developed “side pore” structure. Thus, solvent-resistant membranes for dye/salt separation with high flux were finally obtained. The successful modification of MMT was demonstrated by FTIR, XRD, TGA and XPS. EDX and SEM were used to characterize the surface segregation phenomena and well-developed pore structures of the membranes. When EPTAC-CD-MMT was added at 3 wt%, the membranes showed a significant increase in pure water flux (138.0 L·m−2·h−1·bar−1), high dye rejection (>98.5 %), low salt rejection (<10.0 %), and good solvent resistance in six organic solvents. This demonstrated the potential of PI/EPTAC-CD-MMT separation membranes for the treatment of dye wastewater containing sophisticated organic solvents.

Montmorillonite-modified stabilizing SA/CMC gel spheres cross-linked by lanthanum for tetracycline hydrochloride removal

In this study, a stable gel sphere was successfully prepared by crosslinking sodium alginate(SA) with sodium carboxymethyl cellulose(CMC) through La and modified by MMT for removing tetracycline hydrochloride (TCH). The obtained materials have been comprehensively characterized using SEM, FTIR, XRD and XPS. The results of batch experiments showed that La@SA/CMC-MMT-0.5 had a high adsorption capacity of TCH, and its maximum adsorption capacity was up to 420.95 mg/g. The adsorption process followed a pseudo-second-order kinetic model and the Freundlich isotherm model. The removal of TCH was a combined process involving both chemisorption and physical adsorption. Hydrogen-bond and complexation played a primary role in removing process, while the role of static electricity was more limited. The MMT modification not only enhanced adsorption capacity of TCH but also improved the thermal stability of the material by creating a temperature barrier and promoting hydrogen-bond. La substitution of metal ions in MMT and electrostatic attraction by MMT-surface negative charges contributed to reducing La-release. In application experiments, the La@SA/CMC-MMT-0.5 showed a high adsorption capacity, strong anti-disturbance performance, and good reusability. Therefore, La@SA/CMC-MMT-0.5 holds great potential for the effective adsorption of TCH in aqueous environments.

Dual-drug (Curcumin/Ciprofloxacin) loading and release from chitosan-based hydrogels embedded with magnetic Montmorillonite/Hyaluronic acid for enhancing wound healing

Montmorillonite (MMt) is extensively applied as an efficient drug-carrier in designing drug delivery systems (DDS) due to its high specific surface area to load drugs. Modification of MMt via iron (Fe) blending can thus be a desirable method to improve its biocompatibility. Herein, magnetic nano-carriers involving the magnetic MMt (mMMt) core surrounded by chitosan (Chito) as a biopolymer and hyaluronic acid (HA) were prepared. To coat the mMMt fabricated through the coprecipitation of the Fe3+/Fe2+ ions in the presence of MMt, the acquired mMMt as the core was then treated with the Chito/HA solution to induce the cross-linked Chito/HA as the shell (namely, the Chito/HA-mMMt). The transmission electron microscopy (TEM) results accordingly revealed the existence of the mMMt inside the Chito/HA solution. Curcumin (CUR) and ciprofloxacin (CIP) were further employed as two model drugs. The CUR and CIP release from the Chito/HA-mMMt subsequently occurred in a sustained manner and pH-dependently. Additionally, an upsurge in the CUR and CIP release by applying an external magnetic field was observed. Thus, the prepared Chito/HA-mMMt hydrogels promise an outstanding potential performance in terms of expanding novel pH-dependent DDS with a sustained release behavior. The scratch assay of the given hydrogels also confirms their applications for wound healing.

Preparation and characterization of novel MP-MMT/PMMA composite microspheres

Melamine polyphosphate (MP), a halogen-free flame retardant was utilized to prepare flame retardant enhanced montmorillonite (MP-MMT), which was introduced into polymethyl methacrylate (PMMA) by emulsion polymerization to improve its heat resistance and flame retardancy. The decorated PMMA were characterized by SEM, FTIR, XRD, and XPS, indicating that MP-MMT/PMMA composites were successfully prepared. The resulting composites exhibited excellent heat resistance, the temperature at maximum weight loss rate was increased from 360 °C to 377 °C, and the char residue at 500 °C was increased to 1.93%. In addition, the LOI value of PMMA composite system was increased from 17.2% to 22.4%, and MP-MMT/PMMA-3 achieved UL-94 V-1 rating. Compared with pure PMMA, the total heat release and peak heat release rate of MP-MMT/PMMA were reduced by 23.0% and 32.4%, respectively. The total smoke release of the optimal flame-retardant PMMA resin decreased by 22.1%, the CO production increased slightly, and the CO2 production decreased significantly. This indicates that the incorporation of MP-MMT has a good effect on flame retardancy. Finally, the flame retardant mechanism of MP-MMT to inhibit PMMA combustion was analyzed. The intercalation modification of MMT is potentially valuable for flame retardant studies of PMMA.

Novel superhydrophobic NIR reflective coatings based on Montmorillonite/SiO2 composites for Energy-saving building

In recent years, cool building materials have received increasing attentions due to their superior energy-saving efficiencies. In this work, novel self-cleaning cool coatings based on fluorocarbon resin-montmorillonite (MMT)/SiO2 composites were prepared for energy-saving buildings. The intercalation modification of MMT improved the dispersion stability of MMT in organic solvent. Surface modification of MMT and SiO2 particles by fluoroalkyl silane (FAS) produced hydrophobic particles. Fluorocarbon resin was used as a binder. With the assistance of the micro/nano structure of montmorillonite/SiO2 composites and low surface energy of FAS and fluorocarbon resin, superhydrophobic state of the MMT/SiO2 composite coatings can be achieved. The maximum contact angle of the MMT/SiO2 composite coatings was as high as 163.5°. The superhydrophobic composite coatings exhibited superior self-cleaning property and good mechanical durability. Furthermore, the NIR solar reflectance of the superhydrophobic montmorillonite/SiO2 composite coatings ranged from 0.77 to 0.85. The composite coatings reduced the heat box’s inside temperature of by 5.9℃. Therefore, the integration of high NIR reflectance property and superior self-cleaning property makes montmorillonite/SiO2 composite coatings good candidates as self-cleaning cool roof coatings for energy-saving buildings.

LDPE:PLA and LDPE:PLA:OMMT polymer composites: Preparation, characterization, and its biodegradation using Bacillus species isolated from dumping yard

AbstractThe focus of the present research is on the biodegradation of low density polyethylene (LDPE):polylactic acid (PLA) and LDPE:PLA:organo modified montmorillonite (OMMT) polymer nanocomposites. PLA was synthesized using the polycondensation method. The surface modification of nanomaterials is affected by various factors such as modifying agent, dispersion medium, and the dispersion of nanoparticles. Ultrasound cavitation technique improves the better dispersion of MMT in reaction mixture and enhances the interaction rate of a modifying agent with clay layered structure. A mixture of aminopropyltriethoxysilane and octadecyl amine was used for the surface modification of MMT. Polymer nanocomposite was prepared using the melt mixing method and used further for the biodegradation study. The mesophilic bacterium isolated from the dumping yard, identified by the 16rRNA technique, was capable of biodegradation of LDPE:PLA and LDPE:PLA:OMMT polymer nanocomposites. Isolated bacterial AP1 is 96.05% identical to the current MCCC1A02146 strain of Bacillus albus. After 50 days of incubation, the polymer nanocomposite sheet was characterized using Fourier transform infrared, X‐ray powder diffractometer, UV–Visible spectroscopy, Field Emission Scanning Electron Microscope (FESEM), etc. Further, LDPE:PLA30% (17.5%) and LDPE:PLA30%:OMMT4.5phr (19.20%), shows maximum percentage degradation. It has been observed that the addition of OMMT contributes to an enhancement in the polymer nanocomposite degradation because it has a large d‐spacing gap that is (21 Å) that enables the water to penetrate in the polymer matrix and increases the growth of bacteria within the polymer matrix. The highest change in biomass and change in extracellular protein content was found to be (39.11 mg/L and OD 0.38) LDPE:PLA30%:OMMT4.5phr composites. In addition, the mechanical properties decrease effectively after the incubation period, for LDPE:PLA 30% and LDPE:PLA30%:OMMT4.5phr.

Capture effect of Pb, Zn, Cd and Cr by intercalation-exfoliation modified montmorillonite during coal combustion

Raw montmorillonite (MMT) was modified by intercalation-exfoliation method to improve the capture capacity of heavy metals (Pb, Zn, Cr and Cd) during coal combustion. Scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR) Spectroscopy and Brunner-Emmett-Teller (BET) indicated that intercalation agents cetyltrimethylammonium bromide (CTAB) and sodium dodecyl benzene sulfonate (SDBS) could be successfully inserted into the interlayer of MMT during the intercalation step, additionally exfoliation process could peel off the MMT into fine flakes. The co-combustion of coal and MMTs was conducted in a tube furnace from 900 to 1300 °C. Results indicated that with the increase of temperature, the retention ratio of Pb, Zn and Cd gradually decreased, especially higher than 1200 °C with a great capture capacity reduction, whereas for Cr, it rose first and then decreased. The capture performance of modified MMT on Pb, Zn and Cr was obviously improved. However, for Cd, adverse effect was observed, of which the capacity was even worse than that of raw MMT in some cases. According to the mechanism analysis, the intercalation-exfoliation modification of MMT primarily enhances the chemisorption of heavy metals by exposing more active sites, which facilitates the fixation of heavy metals in the form of aluminosilicates.

Effect of POSS-Modified Montmorillonite on Thermal, Mechanical, and Electrical Properties of Unsaturated Polyester Nanocomposites.

Montmorillonite (MMT) displays excellent cohesion with an unsaturated polyester (UP) matrix to generate a material which exhibits an extensive range of commercial applications. The organic modification of MMT using polyhedral oligomeric silsesquioxanes (POSS) and the effect of POSS-MMT on the thermal, mechanical, and electrical properties of UP are reported here. Transmission electron microscopy (TEM) images were used to characterize the modification of MMT using POSS. Modified MMT (POSS-MMT) was incorporated, at different wt.% (0.5, 1, 3, 5), into UP via in-situ polymerization. The presence of POSS-MMT enhanced the characteristic properties of UP as a consequence of good dispersion in the polymer matrix. Scanning electron microscopy (SEM) images support effective POSS-MMT dispersion leading to tensile strength enhancement of a UP/POSS-MMT nanocomposite (3 wt.% POSS-MMT) by 54.7% as compared to that for unmodified UP. TGA displays a 35 °C improvement of thermal stability (10% mass loss) at 5% POSS-MMT incorporation, while the electrical conductivity is improved by 108 S/m (3 wt.% POSS-MMT) in comparison to that for unmodified UP. The conventional obstacle of UP associated with shrinkage weight loss during curing seems to be moderated with POSS-MMT incorporation (3%) resulting in a 27.8% reduction in shrinkage weight loss. These fabricated nanocomposites expand the versatility of UP as a high-performance material owing to enhancements of properties.

Development of a water erosion tracer using industrial residue as a source of rare earth elements

This study was aimed at developing a water erosion tracer from montmorillonite (MMT) chemically modified with rare earth elements (REE) as chemical signatures to understand the landscape sediment mobilization dynamics. A new route of development involving the use of an industrial residue from the REE extraction process was evaluated for its REE incorporation efficiency in the clay mineral to enable further tracer applications on a field scale. This industrial residue-modified MMT tracer was compared with a reference tracer based on the chemical modification of MMT with a commercial REE precursor. These REE-modified MMT tracers were characterized by Fourier transform infrared spectroscopy (FTIR) and X-ray fluorescence spectroscopies, inductively coupled plasma mass spectrometry (ICP-MS), X-ray diffractometry, scanning electron microscopy (SEM), and N2 physisorption measurements were performed to verify whether the MMT tracer modified with the industrial residue had the same chemical signature (REE) content and chemical stability as those of the commercial REE precursor-based tracer. Chemical stability tests under different pH conditions were carried out to evaluate possible REE content variations in the tracers, mainly over the targeted soil pH range (pH = 4.0–7.7). The clay modified with the industrial residue was further submitted to laboratory horizontal mobility tests using a soil flume. The chemical modification method was effective in producing a chemically stable MMT-based tracer that also displayed multi-chemical signature due to the use of the ClLa40-INB solution, which will potentially enhance the tracer detection in sediments. The mobility tests confirmed the suitability of the modified clay as a tracer.

A new method combining modification of montmorillonite and crystal regulation to enhance the mechanical properties of polypropylene

This study focused on montmorillonite modification and crystal structure regulation, to prepare polypropylene/montmorillonite composites with high stiffness and toughness simultaneously. A kind of organic montmorillonite was prepared successfully through a new and simple method, which was introducing Fe3+ and stearic acid into interlamination of montmorillonite. The maximum interlayer spacing of organic montmorillonite could be expanded from 1.25 nm to 4.66 nm, and the organic montmorillonite formed an intercalated structure in matrix during melting process. The production of β crystal induced by TMB-5 could solve the problem of embrittlement. The reinforcing effect of montmorillonite combined with toughening of TMB-5 was expected to endow composite with balanced stiffness and toughness, presenting improvement simultaneous in the tensile modulus, flexural modulus and impact strength by 21.0%, 31.4%, 49.6% respectively compared to PP. This paper provided a new and facile method in modification of MMT and a strategy to optimize overall mechanical performance of nanocomposite.

GPTMS-Montmorillonite-filled biopolymer chitosan membrane with improved compatibility, physicochemical, and thermal stability properties ochemical and thermal stability properties

The chitosan/organo-montmorillonite (Ch/O-MMT) membrane was fabricated and tested. Surface modification of O-MMT particles using 3-glicydoxy propyl trimethoxysilane (GPTMS) to enhance its compatibility with chitosan is presented. The resulting composite membrane was characterized by using SEM, AFM, and FTIR to observe the morphological and functional group structure. The crystallinity, thermal stability, and mechanical strength was analyzed by XRD, TGA, and tensile test. The results suggested that the modification of MMT using GPTMS could increase the compatibility of O-MMT with chitosan membrane, thus producing a good composite membrane with well-dispersed MMT filler within the chitosan polymer matrices. Based on the FTIR analysis, the presence of GPTMS could improve the interaction between chitosan and O-MMT material, thus forming more hydrogen bonding with chitosan membrane than Ch/MMT membrane. The TGA curve analysis showed that the addition of inorganic filler into chitosan organic matrices was able to increase the thermal stability of Ch/MMT and Ch/O-MMT composite membrane, suggested to mechanical strength analysis. The improvement in thermal stability was due to the absence of hydrogen bonding formations between chitosan polymer and O-MMT filler. In addition, greater hydrogen bonding formation would lead to the tighter packing of Ch/O-MMT composite membrane, resulting in higher bonding strength and higher thermal resistance. All of the characterization results confirmed that the Ch/O-MMT composite membrane has better physicochemical properties than Ch/MMT composite membrane.

Synthesis of polymer hybrid latex polystyrene methylmethacrylate-co-butylacrylate with organo-montmorillonite as filler through miniemulsion polymerization for barrier paper application

Nanocomposite have a huge potential in the future technologies and scientific communities. It is possible to design new materials with a simple modification and new materials have different properties and improvement in its mechanical properties and application fields. Hybrid latex based on monomer styrene (St), butyl acrylate (BA) and methylmethacrylate (MMA) have been studied and used for barrier paper applications in food industries in order to replace polypropylene (PP), polyethylene (PE) or polyethylene terephthalate (PET) materials. To achieve better hybrid materials, various techniques and materials have been utilized, montmorillonite (MMT) from smectite family have been selected as filler in order to synthesize polymer clay nanocomposites (PCNs). The selection of MMT as filler due to its high aspect ratio, high modulus and high cation exchange capacity (CEC). MMT was not susceptible to common polymer due to its organophobicity, low basal spacing, and incompatible to common monomers phase. Surface modification of MMT with traditional ion exchange method can be done through ion exchange with quaternary alkyl ammonium surfactants. The objective of surface modification of MMT are to change its nature hydrophilicity to organophilicity, in the same time to increase its basal spacing. Various quaternary alkylammonium cationic surfactants have been used; in this study, three type of alkylammonium were selected to be used due to its different in alkyl carbon chain lengths. Intercalation of surfactants cation in MMT depend on the layer-charge alkyl carbon chains, selection of myristyltrimethylammonium bromide (MTAB) with C17 carbon chains, cetyltrimethylammonium bromide (CTAB) with C19 carbon chains and octadecyltrimethylammonium bromide (OTAB) with C21 carbon chains could give an answer of the selection of organoclay that compatible with St, BA and MMA. This study focuses on the microstructure of organo montmorillonite (OMMT) after surface modification and the potential to be used as filler in synthesis of hybrid latex through miniemulsion polymerization technique. The intercalation or exfoliation of MMT through ion exchange with alkylammonium surfactant were studied, interlayer spacing of OMMT were analysed with X-ray diffraction, small angle X-ray scanning (SAXS) technique, presence of cationic surfactant in the interlayer space and bond character and arrangement of surfactant ions were analysed by Fourier Transform Infrared (FTIR), Thermogravimetric analysis (TGA) and Transmission Electron Microscope (TEM). Synthesis of hybrid latex was done by miniemulsion polymerization technique with selected OMMT filler. Series of experiments were performed to study the polymerization variables such as filler loading, role of surfactant/cosurfactant and filler solubility in monomer emulsions. The results shown that water soluble surfactant SDS in miniemulsion polymerization resulted lower coagulum and smaller particle size compare to non-ionic surfactant (TX405) and cationic surfactant (OTAB). Combination of non-ionic surfactant (TX405) with ionic surfactant (SDS) with ration 1:2 showed the better results than SDS alone, with lowest coagulum, narrow particle size distribution, and lowest Broekfield Viscosity. Scale up loading level of OMMT filler in miniemulsion to 5.0 wt%, resulting instability before and after polymerization with regard to high coagulum content and low monomer conversion rate (<90%). The hybrid latex resulted from miniemulsion polymerization will be applied on paperboard with hand rod coater with coating weight 15-20 gsm. The coated paperboard tested on its water vapour transmission rate (WVTR) together with paperboard coated with PE from melt blending process. Paperboard coated with hybrid latex comparable to paperboard coated with PE, indicated improvement in its WVTR value compare to paperboard coated with latex without filler addition. The main target of this research was to synthesis polymer hybrid latex for super barrier material for food packaging in order to replace unrecyclable PP, PE or PET. The utilization of polymer hybrid latex could benefit paper and paperboard packaging industries.

Evaluation of mechanic damping properties of montmorillonite/organo-modified montmorillonite-reinforced cement paste

In this study, the mechanical and damping properties of montmorillonite (MMT)/organo-modified montmorillonite (OMMT) reinforced cement paste were investigated. The damping properties were measured by dynamic mechanical analysis (DMA). The compressive strength of cement composites was decreased by a high dosage of MMT or OMMT. The damping capacities of OMMT-reinforced cement paste was superior to that of MMT-reinforced cement, in which the damping mechanism comprised the internal friction, external friction, and multiphase friction within the cement matrix. Moreover, a constrained-layer damping structure was produced in cement paste by the organic modification of MMT and was beneficial to the damping properties of cement paste.

Surface modification of MMT and its effect on fatigue and fracture behavior of basalt/epoxy based composites in a seawater environment

In this study, silanized-montmorillonite (Si-MMT) reinforced basalt fiber/epoxy composites were prepared and the effect of silanization of MMT on the fatigue and fracture behavior of the composites in seawater condition were analyzed. To compare the properties of Si-MMT/basalt/epoxy (Si-MMT BFRP), Pure basalt/epoxy (pure BFRP) composites were scrutinized in both dry and seawater conditions. The structural changes after silane-treatment were confirmed using TEM, XRD, and FTIR. Further, tensile strength, cyclic loading (fatigue) and fracture properties were studied through the universal testing machine (UTM) and FE-SEM of the fractured surface. It was found that the properties were improved after silanization of MMT due to the better compatibility and dispersion of MMT layers in the matrix. After seawater absorption, debonding occurred due to swelling of the polymer. Hence, deterioration in the properties was observed. However, the composites with Si-MMT still showed better performance among all.

Thermal Degradation Characteristic and Flame Retardancy of Polylactide-Based Nanobiocomposites.

Polylactide (PLA) is one of the most widely used organic bio-degradable polymers. However, it has poor flame retardancy characteristics. To address this disadvantage, we performed melt-blending of PLA with intumescent flame retardants (IFRs; melamine phosphate and pentaerythritol) in the presence of organically modified montmorillonite (OMMT), which resulted in nanobiocomposites with excellent intumescent char formation and improved flame retardant characteristics. Triphenyl benzyl phosphonium (OMMT-1)- and tributyl hexadecyl phosphonium (OMMT-2)-modified MMTs were used in this study. Thermogravimetric analysis in combination with Fourier transform infrared spectroscopy showed that these nanocomposites release a smaller amount of toxic gases during thermal degradation than unmodified PLA. Melt-rheological behaviors supported the conclusions drawn from the cone calorimeter data and char structure of the various nanobiocomposites. Moreover, the characteristic of the surfactant used for the modification of MMT played a crucial role in controlling the fire properties of the composites. For example, the nanocomposite containing 5 wt.% OMMT-1 showed significantly improved fire properties with a 47% and 68% decrease in peak heat and total heat release rates, respectively, as compared with those of unmodified PLA. In summary, melt-blending of PLA, IFR, and OMMT has potential in the development of high-performance PLA-based sustainable materials.