Montmorillonite Nanocomposites Research Articles

Theoretical modeling of predicting elastic modulus of polyurethane copolymer/organic-montmorillonite nanocomposite

A structure of theoretical models set was suggested to predict the elastic moduli of polyurethane copolymer (PUC)/organic modified montmorillonite (OMMT) nanocomposites (NCs) in terms of length (L) to thickness (t) ratio and volume fraction ([Formula: see text]) of OMMT nanoparticles. The predicted elastic modulus outcomes of PUC/OMMT NCs were compared with experiment data. The outcome demonstrated that the suggested aspect ratio of predicted elastic modulus decreased with increased [Formula: see text] of OMMT compared to experimental data. The largest value of effective aspect ratio belonged to the Hui–Shia model over all OMMT [Formula: see text]. The modified Halpin–Tsai model incorporated with the factor for decreasing modulus (FFDM) recorded the lowest range of percentage error between theoretical and experimental data around 0.385–0.816% at [Formula: see text] (4[Formula: see text]wt.%) OMMT.

Synthesis of nanocomposites of montmorillonite with carbon nanotubes as a potential material for water purification

The main goal of this research is to create nanocomposites based on unmodified and iron-modified (FeNP) montmorillonite (Mt) and carbon nanotubes (CNT) synthesized using the chemical vapor deposition method. The target area for the application of these materials is the creation of water treatment systems. This paper compares the efficiency of the CNT synthesis process on Mt before and after modification with FeNP of different concentrations and provides the characterization of the CNT microstructure and structure using different methods, such as scanning electron microscopy, high-resolution transmission electron imaging, and Raman spectroscopy. For initial verification of properties important for water purification, Mt+CNT and Mt+FeNP+CNT nanocomposites on a carbon nonwoven fabric (CF) are tested in this work. Incubation of the above-mentioned samples in a water–oil mixture reveals complex adsorption dynamics. The CF+Mt+FeNP+CNT sample shows a very good oil adsorption capacity due to its superhydrophobic and oleophilic properties.

Mechanical property analysis of carbon-bamboo fiber–reinforced montmorillonite nanocomposite

Mechanical property analysis of carbon-bamboo fiber–reinforced montmorillonite nanocomposite

Time- and temperature-dependent mechanical and rheological behaviours of injection moulded biodegradable organoclay nanocomposites

Injection moulded specimens were produced from biodegradable poly(butylene succinate) (PBS)/organomodified montmorillonite (OMMT) nanocomposites, after melt compounding in different compositions. WAXD studies demonstrated that the OMMT formed similar intercalation levels in the 2.5–10 w/w% additive ratio range. It was also proved by rotational rheometry that the nanoclay stacks form physical network above 5 w/w% concentration, which significantly influence the viscoelastic properties of the melt. The value of zero shear viscosity also changed accordingly, starting to increase above 5 w/w% nanoclay content. The OMMT content reduced the creep sensitivity measured in molten state.X-ray and DSC investigations showed that OMMT inhibits the crystallisation of PBS, resulting in a decrease in crystallinity at higher nanoclay ratios. As a result, the room temperature creep increased with the OMMT ratio.The Young's modulus linearly increases in the entire concentration range exceeding 1.2 GPa at 10 w/w% nanoclay content. The value of yield strength does not change significantly (35–40 MPa), but the strain at yield – which characterises stiffness – and the notched Izod impact strength already decrease at 2.5 w/w% OMMT content, but further increasing the nanoclay content has minor effect. However, the nanocomposite with 10 w/w% OMMT can be a real alternative to polypropylene (PP) and high-density polyethylene (HDPE) injection moulded products based on its mechanical properties.To characterise the effect of OMMT on dynamic mechanical properties, the S (Stiffening effectiveness), L (Loss effectiveness) and D (Damping effectiveness) indices were introduced to quantitatively describe the nanoclay effect intensity in each temperature range.

Chitosan-Pd0 nanoparticles encapsulated in Al, Co-pillared montmorillonite by one-pot process

Chitosan-Pd0 (CS-Pd0) nano particles encapsulated in Al, Co-pillared montmorillonite (MMt) nanocomposites were synthesized by a facile one-pot heat treatment method. The MMt was impregnated with Al, Co pillaring reagent, protonated chitosan solution, and Na2PdCl4 solution, followed with a controlled low-temperature (200 °C) heat treatment, resulting in Pd@CS/Al, Co-MMt nanocomposites. Al, Co pillaring effectively expanded the basal spacing of MMt layers from 1.24 nm to 1.82 nm, and generated numerous mesopores in interlayer space, resulting in increase of surface area from 11.8 m2/g to 198.3 m2/g. Due to the well encapsulation of CS chains in the interlayer nano-spaces, the specific surface area of the hybrid nanocomposite underwent a reasonably decrease as the CS content increase. Most of nano-sized Pd species (2–3 nm) chelated with CS chains dispersed well in the interlayer space of the porous Al, Co pillared MMt matrix. The resultant nanocomposite prepared by such facial one-pot process method have similar high comprehensive catalytic performances as applied in coupling reactions to that prepared by regular divided-multistep method. Moreover, it is confirmed that Al pillaring doped with Co and encapsulation of CS chains have synergistic improving effects on the comprehensive catalytic performance of the nanocomposites.

Cu2+ cation-doped montmorillonite nanocomposites: Synthesis, characterization and antibacterial activity

Cu2+ cation-doped montmorillonite nanocomposites: Synthesis, characterization and antibacterial activity

Evaluation of newly copolymers and their montmorillonite nanocomposite as cold flow improver for petroleum lubricating oil

The great demand on the energy makes the attention toward modifying lubricating oil. This work tends to prepare the following copolymers; octadecylmethacrylate-co-dodecene (CP1) and octadecylmethacrylate-co-hexadecene (CP2) by free radical solution polymerization using laboratory prepared octadecylmethacrylate monomer with either 1-dodecene or 1-hexadecene. The same monomers also used to prepare their polymers nanocomposite (NP1, NP2) with 1% of nanomontmorolonite by emulsion polymerization. The structures of the prepared polymers and their nanocomposite were elucidated by FTIR, 1HNMR, TGA, DSC, TEM and DLS. These polymers were used as pour point depressant, flow improver and viscosity modifier and showed high efficiency. After comparison of the data of the polymers and their nanocomposite, the nanocomposite give the best results where the pour point decreased from 0 °C to − 18, − 27, − 24 and − 33 °C for CP1, CP2, NP1 and NP2 respectively at the optimum concentration 10,000 ppm. On the other hand the viscosity index increased from 86.57 to 93.25, 92.41, 94.17 and 93.103 for CP1, CP2, NP1 and NP2 respectively, the apparent viscosity increased from 55.863 to 69.31, 119.41, 111.28, and 166.89 cP also the yield stress increased from 652.19 to 1076.3, 1074 and 1480 D/cm2 for CP1, CP2, NP1 and NP2 respectively.

Effect of Repeated Extrusion Cycles on the Structure and Properties of Polypropylene/Polyolefin Elastomer/Organic Montmorillonite Nanocomposites Using a β-Nucleating Agent

In this study the compatibilizer, maleic anhydride/hydroxyethyl acrylate-grafted-polyolefin elastomer (POE-g-MAH/HEA), was utilized in the preparation of polypropylene/polyolefin elastomer/organic nano-montmorillonite (PP/POE/OMMT) nanocomposites with a β-nucleating agent (β-NA) via twin-screw extrusion. The impact of repeated extrusion cycles (up to three) on the properties and structure of the nanocomposites was investigated. The results indicated that the dispersion of the OMMT within the polymer matrix improved with increased extrusion cycles, thereby enhancing the interfacial interactions between the constituents. In addition, the OMMT platelets led to increased crystallinity of the nanocomposites, accompanied by polymer chain degradation. The second extrusion cycle resulted in the nanocomposite with the best melt strength and mechanical properties. Additionally, the three cycles of additional repeated extrusion significantly enhanced the thermal stabilities of the nanocomposites.

Bioinspired design of nitrile-butadiene rubber/montmorillonite nanocomposites with hydrogen bond interactions leading to highly effective reinforcement

An efficient and environmentally friendly strategy was demonstrated for enhancing the interfacial interaction between nitrile-butadiene rubber (NBR) and montmorillonite (MMT) nanocomposites. Herein, we coated the MMT surface with a thin coating of polydopamine (PDA), and then compounded PDA-coated MMT (DMMT) gel with the solid NBR via gel compounding method to obtain NBR/DMMT nanocomposites. It was revealed that the hydrogen bond interactions between DMMT and NBR are responsible for the nanodispersion of DMMT as well as for effective stress transfer. This led to a great improvement in the mechanical properties of the NBR/DMMT nanocomposite at low DMMT loading. Using only 6 phr DMMT, the tensile strength of NBR/DMMT nanocomposite was able to achieve 15.9 MPa, which is 4.1 times that of pure NBR.

Enhancing the Properties of Water-Soluble Copolymer Nanocomposites by Controlling the Layer Silicate Load and Exfoliated Nanolayers Adsorbed on Polymer Chains

Novel polymer nanocomposites of methacryloyloxy ethyl dimethyl hexadecyl ammonium bromide-modified montmorillonite (O-MMt) with acrylamide/sodium p-styrene sulfonate/methacryloyloxy ethyl dimethyl hexadecyl ammonium bromide (ASD/O-MMt) were synthesized via in situ polymerization. The molecular structures of the synthesized materials were confirmed using Fourier-transform infrared and 1H-nuclear magnetic resonance spectroscopy. X-ray diffractometry and transmission electron microscopy revealed well-exfoliated and dispersed nanolayers in the polymer matrix, and scanning electron microscopy images revealed that the well-exfoliated nanolayers were strongly adsorbed on the polymer chains. The O-MMt intermediate load was optimized to 1.0%, and the exfoliated nanolayers with strongly adsorbed chains were controlled. The properties of the ASD/O-MMt copolymer nanocomposite, such as its resistance to high temperature, salt, and shear, were significantly enhanced compared with those obtained under other silicate loads. ASD/1.0 wt% O-MMt enhanced oil recovery by 10.5% because the presence of well-exfoliated and dispersed nanolayers improved the comprehensive properties of the nanocomposite. The large surface area, high aspect ratio, abundant active hydroxyl groups, and charge of the exfoliated O-MMt nanolayer also provided high reactivity and facilitated strong adsorption onto the polymer chains, thereby endowing the resulting nanocomposites with outstanding properties. Thus, the as-prepared polymer nanocomposites demonstrate significant potential for oil-recovery applications.

Pd-ZnO nanoparticles decorated acid activated montmorillonite for the efficient removal of cationic dyes from water

Efficient adsorbent being the need of the hour for the effective removal of dye stuff from textile effluents, we herein report the synthesis of palladium intercalated zinc oxide nanoparticles decorated acid activated montmorillonite (Pd-ZnO@H+-Mt)nanocomposite using ion-exchange process followed by wet impregnation technique with Citrus limon leaf extract as reducing agent and its application as an efficient adsorbent for methylene blue (MB) and malachite green (MG) removal from water. The successful intercalation of Pd into the ZnO lattice was identified by band gap value calculated using UV-DR spectra. ATR FT-IR, XRD, SEM, TEM, TGA, BET, and XPS techniques confirmed the successful preparation of Pd-ZnO@H+-Mt nanocomposite. The synthesized Pd-ZnO@H+-Mt nanocomposite was then evaluated for efficient uptake of cationic dyes through batch adsorption experiments and thereby various parameters that influenced adsorption process were found. The experimental maximum adsorption capacity, qm of Pd-ZnO@H+-Mt for MB and MG dyes were 205 and 167 mg/g. The main driving force for the adsorption of MB and MG was identified to be the presence of mesopores, high specific area of Pd-ZnO@H+-Mt on acid activation, total pore volume and the presence of Pd-ZnO NPs on the surface which enhanced the negative charges of Mt surface thus facilitated better loading of dye molecules. Multilayer coverage of MB/MG molecules on Pd-ZnO@H+-Mt were evidenced through Freundlich isotherm model and experimental data of both MB and MG were described well by pseudo second-order kinetic model. The adsorption phenomenon was identified as feasible, spontaneous, and endothermic for MB adsorption while exothermic for MG adsorption. Moreover, the adsorbent could be recycled thrice. Thus, the synthesized Pd-ZnO@H+-Mt nanocomposite could be utilized effectively in industrial water treatment for the removal of dye stuff as adsorbent.

Insights of Montmorillonite Clay Nanocomposites for Adsorption of Toxic Colorant and Metals Ions from Wastewater: A Mini Review

The development of lowcost adsorbents is triggered often by not utilizing the costly starting material that pave the path for synthesizing cost comparative adsorbents for purpose of sequestration of toxic pollutants from water. Clay minerals are alternatives that are low-cost to activated charcoal due to their abundance presence, excellent textural properties, high specific surface area, strong chemical, and mechanical stability Pollution, in recent years has become an increasingly serious problem, leading to health issues in human and deteriorating environmental condition. Various remediation technologies are introduced so far, but adsorption regarded as important industrial technique for separation and purification of effluent media. This review paper showcases the importance of montmorillonite nanocomposites for the remediation of toxic contaminants from water. The preferred method of remediation is adsorption. It also emphasizes the recent development in the field of montmorillonite nanocomposites in sequestering different types of dyes and various heavy metals from water. Hence, this brief review authorises the various montmorillonite adsorbents conceivability towards water treatment.

Electrochemical stripping voltammetrical sensor based on polypyrrole exfoliated polyetheramine-montmorillonite nanocomposite for nanomolar detection of nifuroxazide.

A series of polypyrrole/polyetheramine-montmorillonite nanocomposites have been fabricated by the intercalation of different types of polyoxyalkylene amine hydrochloride (Jeffamines: D400, D2000, T5000, and T403) into montmorillonite layers via the cation-exchange process followed by in situ polymerization of pyrrole. The physicochemical characteristics of as-prepared nanocomposites were investigated using Fourier transform infrared (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer-Emmett-Teller (BET), and electrochemical impedance spectroscopy (EIS) instruments. The change of the types of Jeffamine causes a change in the geometrical structure, and surface area of nanocomposites. Noteworthy, the resulting polypyrrole/D2000-montmorillonite ([PDM-50]) nanocomposite exhibited a cauliflower-like shape with a specific surface area (116.2 m2 g-1) with the highest conductivity. Furthermore, the modified stripping voltammetric carbon paste sensor was fabricated based on 1.0% [PDM-50] nanocomposites to detect the drug nifuroxazide (NF). The sensor achieved detection limits (LD) of 0.24, and 0.9 nM of NF in the medication, and human urine fluid, respectively. This sensor showed appropriate repeatability, reproducibility, stability, and selectivity for NF sensing in different fluids accompanied by other interferents.

Improved Conductivity in Gellan Gum and Montmorillonite Nanocomposites Electrolytes.

Nanocomposite polymer electrolytes (NPEs) were obtained using gellan gum (GG) and 1 to 40 wt.% of montmorillonite (Na+SYN-1) clay. The NPEs were crosslinked with formaldehyde, plasticized with glycerol, and contained LiClO4. The samples were characterized by impedance spectroscopy, thermal analyses (TGA and DSC), UV-vis transmittance and reflectance, X-ray diffraction (XRD), and continuous-wave electron paramagnetic resonance (CW-EPR). The NPEs of GG and 40 wt.% LiClO4 showed the highest conductivity of 2.14 × 10-6 and 3.10 × 10-4 S/cm at 30 and 80 °C, respectively. The samples with 10 wt.% Na+SYN-1 had a conductivity of 1.86 × 10-5 and 3.74 × 10-4 S/cm at 30 and 80 °C, respectively. TGA analyses revealed that the samples are thermally stable up to 190 °C and this did not change with clay addition. The transparency of the samples decreased with the increase in the clay content and at the same time their reflectance increased. Finally, CW-EPR was performed to identify the coordination environment of Cu2+ ions in the GG NPEs. The samples doped with the lowest copper concentration exhibit the typical EPR spectra due to isolated Cu2+ ions in axially distorted sites. At high concentrations, the spectra become isotropic because of dipolar and exchange magnetic effects. In summary, GG/clay NPEs presented good ionic conductivity results, which qualifies them for electrochemical device applications.

Effect of nanoclay on combustion, mechanical and morphological properties of recycled high density polyethylene/marula seed cake/organo-modified montmorillonite nanocomposites

Effect of nanoclay on combustion, mechanical and morphological properties of recycled high density polyethylene/marula seed cake/organo-modified montmorillonite nanocomposites

Preparation and characterization of sodium polyacrylate grafted montmorillonite nanocomposite for the adsorption of cadmium ions form aqueous solution

High-efficiency adsorbents made from clay minerals have a wide application in remediation of soil and water pollution, especially in the treatment of refractory and highly toxic heavy metals. Montmorillonite itself has a good adsorption capacity and a large modification space for its layered structure. Therefore, carboxylate polymer grafted montmorillonite was developed to improve the adsorption capacity of heavy metals in this paper. Two kinds of modified preparation routes were compared, and a series of batch adsorption tests were conducted to evaluate the influence degree of parameters (contact time, pH, temperature, and cadmium concentration). The structural changes of montmorillonite samples before and after modification were characterized by a series of microscopic analyses and measurement techniques. The results show that the silicon hydroxyl produced by the hydrolysis of silane coupling agent can indeed be grafted by dehydration condensation with Si/Al-OH on clay surface. The grafting chain can be greatly increased by C=C double bond breaking polymerization. The polycarboxylate group can effectively improve the adsorption performance of modified montmorillonite for cadmium ions. The maximum adsorption capacity of modified montmorillonite increased by about 224.75%, reaching 63.49 mg/g. The adsorption model of montmorillonite conforms to Langmuir monolayer adsorption model, while modified montmorillonite samples exhibit Freundlich adsorption model and S-type isothermal adsorption curve characteristics of resin. The preparation method of neutralizing after polymerization of acrylic acid was proposed to be better, which provides technical guidance for scientific and efficient application.

Study on the water‐tree ageing characteristics of polyethylene/organic montmorillonite and crosslinked polyethylene/organic montmorillonite nanocomposites

AbstractThe dispersion state of nanoparticles affects the properties of composites, and the crosslinking process of polymers affects the dispersion state of nanoparticles. In order to investigate the effects of crosslinking behaviour on the water‐tree ageing characteristics of nanocomposite dielectrics at the molecular level, polyethylene/organic‐montmorillonite (PE/organic montmorillonite (OMMT)) and crosslinked polyethylene/organic‐montmorillonite (XLPE/OMMT) nanocomposites were prepared by the melt blending method, after which the accelerated water‐tree ageing experiments were conducted using a needle electrode. Fourier transform infrared spectroscopy, differential scanning calorimetry, successive self‐nucleation annealing and scanning electron microscope (SEM) tests were conducted to characterise the properties of the samples before and after water‐tree ageing. The results indicate that the initiation probability and the length of water trees in XLPE/OMMT are less than those in PE/OMMT. The carbonyl index in the water‐tree area of the two nanocomposites increases, indicating that the water‐tree ageing is the result of electrochemical degradation. The crystallisability of the water‐tree area degrades, decreasing the crystallinity and the lamellar thickness. The growth of water trees destroys molecular chains and crystal structures, which results in local cracks. There are many holes for the water tree growth in the PE/OMMT specimen. However, the crosslinked meshwork not only restricts the movement of macromolecular chains but also increases the stability of the lamellar barrier effect of OMMT. The combination of the two effects significantly improves the water‐tree resistance of the XLPE/OMMT nanocomposite.

Alignment control of clay and its effect on properties of polymer nanocomposites

Polymer nanocomposites are well known to show high performances by the addition of a small amount of nanofiller. However, the brittleness has often been reported as a general issue of the nanocomposites. In this study, we revealed the excellent toughening effect of poly (vinyl alcohol) (PVA)/montmorillonite (MMT) nanocomposites by controlling the alignment of MMT by drawing. The PVA/MMT nanocomposites with 5 wt% MMT loading was prepared and then drawn by uniaxial drawing, roll drawing and simultaneous-biaxial drawing. The drawn nanocomposites, where MMT was highly aligned parallel to the film surface, showed excellent enhancement in the mechanical properties and barrier properties. It is noteworthy that not only the Young's modulus and the tensile strength, but also the elongation at break and the toughness remarkably increased for the drawn nanocomposites. For example, the simultaneously-biaxially-drawn nanocomposite showed the toughness of 17 times higher than that of the as-cast nanocomposite. Furthermore, the swelling ratio was comparable to that of surface fluorinated PVA film.

Praseodymium-oxide decorated montmorillonite nanocomposite as a novel admixture for dredged soil stabilisation

ABSTRACT Herein a novel nanocomposite, Praseodymium oxide-nano montmorillonite (Pr-nMMT)was fabricated and explored as stabilising admixture for enhancing the strength of dredged soils. The compaction, permeability, direct shear, california bearing ratio (CBR), and unconfined compressive strength (UCS) tests performed on the dredged soil samples collected from the Shalimar site along the Dal Lake Srinagar rendered it unsuitable as construction material and needed stabilisation before using it as a building material. Different percentages of Pr-nMMT (0.25–1%) were used for stabilisation purposes and it revealed that the addition of Pr-nMMT to soil increased maximum dry density (MDD), shear strength parameters (angle of internal friction and cohesion), CBR, and decreased optimum moisture content (OMC), plasticity index, and hydraulic conductivity. The UCS enhanced notably with Pr-nMMT content and increment in curing time. The optimum Pr-nMMT content determined was 0.5% as it demonstrated the maximum value of UCS at 0, 7 and 14 days of curing beyond which the strength showed a declining trend. It was anticipated that Pr-nMMT filled pores between soil particles, therefore resisting sliding among soil particles and thus increasing the strength of treated dredged soil. The results portray Pr-nMMT as an efficient nano admixture for the stabilisation of dredged soil.

Enhancing morphological and optical properties of montmorillonite/chitosan-modified cerium oxide nanoparticles for antimicrobial applications

Cerium oxide montmorillonite (CeO2NPs-Mt) nanocomposite has been successfully synthesized using montmorillonite (Mt) as support, Moringa oleifera as a chelating agent, and chitosan as a cross-linking agent with the green hydrothermal method. The molar composition of cerium (Ce) as a precursor and montmorillonite (Mt) as support was varied to 1: 0.5, 1: 1, 1:2, 1:3, and 1:4 to discover the effect of support on morphology, optical properties, and antimicrobial activity of cerium oxide. X-ray diffraction (XRD) analysis result showed the deposition of CeO2NPs on Mt surface. The Fourier transform infra-red (FTIR) analysis revealed the appearance of a Ce-O specific peak in the range of 400–600 cm−1. Based on Transmission electron microscopy (TEM) analysis, the morphology of CeO2NPs-Mt nanocomposite showed reduced agglomeration with nanoparticles dispersed on the support's surface. Scanning electron microscopy (SEM) analysis confirmed that using of Ce: Mt composition of 1:2 resulted in more evenly Ce nanoparticles on Mt support with no agglomeration. Based on the Diffuse Reflectance Spectroscopy UV-Visible (DRS-UV-Vis) analysis result the sample resulted in the largest bandgap energy as well. Nanocomposite Ce: Mt with a molar ratio of 1:2 indicated the good activity of antimicrobial to Pseudomonas aeruginosa, Escherichia coli, and Staphylococcus aureus bacteria, as well as Candida albicans and Aspergillus fumigatus. The result shows that an inhibitory effect of CeO2NPs was increased up to 30% after modification using Mt, showing a highly potential for antimicrobial material to be developed in biomedical applications.