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Ion‐exchange clays containing sodium such as bentonite and montmorillonite have the ability to exchange their cations. Few studies conducted with this type of ion‐exchange pigments are not conclusive about their anticorrosive efficiency. The present research aims to address the study on the anticorrosive efficiency of this type of pigments in chlorinated rubber paints. Sodium‐bentonite was exchanged with Zn, Sr and Zn‐Sr to be applied on low carbon steel specimens and study the anticorrosive performances of these new ion‐exchanged bentonites (IEBs) in anticorrosive paint formulations.

The new pigments were characterised using scanning electron microscopy (SEM) and X‐ray fluorescence (XRF) to determine the CEC (cation exchange capacity) of the different exchanged cations. Evaluation of the ion‐exchanged and Na‐bentonite pigments using international standard testing methods (ASTM) was estimated. Paint systems manufactured with these ion‐exchange pigments have been subjected to adhesion, accelerated corrosion laboratory tests, and EIS in order to assess their anticorrosive behaviour.

The results of this work revealed that the ion‐exchange bentonite (IEBs) pigments showed high anticorrosive performance that can be arranged as follows: Sr‐bentonite was better than Zn‐Bentonite and both were better than the double Zn‐Sr‐bentonite indicating an antagonism behaviour between the two cations when present together.

These pigments can be applied in other polymer composites, e.g. rubber and plastics as reinforcing agent and fillers.

These prepared pigments are environmentally friendly pigments which impart high anticorrosive behaviour to paint films with great economic savings.

The purpose of this paper is to assess sand-bentonite liners (SBL) which could be used as hydraulic barriers with a controllable quality, relatively low cost and easy operation in solid waste landfills.

These barriers have been used successfully in various applications and have attracted much attention in a short period of time. The only precautionary use of SBLs is related to the change of their hydraulic properties in high alkaline chemical environments. The main reason for this phenomenon is the presence of high ion exchange minerals in bentonite. By exposure to these environments, it is also laid open to degradation of the montmorillonite microstructure leads to change in hydraulic behavior. Three different compounds were used for laboratory-scale SBL, and diffusion was considered as the dominant mechanism of contamination transmission in these liners. Chlorine ion has been used as pollutant, and its diffusion coefficient was determined in the tested SBLs.

The sample’s diffusion coefficient for the first experiment containing 3% bentonite and 97% Semnan sand were 2.5 × 10^(−9) (m^2/s) and 2.44 × 10 ^(−9) (m^2/s), respectively. Similarly, for two samples with 6% bentonite and 94% Semnan sand, this parameter was equal to 2.17 × 10 ^(−9) (m^2/s) and 2.22 × 10 ^(−9) (m^2/s) and for two samples with 3% agglacial clay, 12% bentonite and 85% Semnan sand was 5.55 × 10 ^(−10) (m^2/s) and 6.11 × 10 ^(−10) (m^2/s). These values correspond to the range reported in previous studies. Also, it was observed that with comparing the diffusion coefficients of test, it was concluded that with increasing bentonite, the molecular diffusion decreases significantly.

In this study, three laboratory samples with different percentages of bentonite, clay and sand were considered and the results obtained from the laboratory were compared with the results obtained from numerical modeling.

The mixture of attapulgite and bentonite was used as a thickener, and polyalphaolefin was used as the base oil to prepare the new lubricating grease. Some solid particles such as Polytetrafluoroethene (PTFE), MoS2, nano-calcium carbonate and graphite were added in the new lubricating grease as anti-wear additives to investigate the tribological sensitivity.

The new lubricating grease was evaluated by optimol-SRV reciprocating friction and wear tester, and the wear volumes were determined using a MicroXAM-3D. At the same time, the dropping point and the cone penetration were investigated and analyzed. The tribological properties of the new lubricating grease and the sensitivity of some solid lubricating additives to the new lubricating base grease were investigated; pure organic-bentonite and pure organic-attapulgite base grease were used as contrast.

The new lubricating grease based on the surface-modified bentonite/attapulgite clay base grease was synthesized with a relatively high dropping point, and the mass ratio is 25/75 bentonite/attapulgite clay base grease, having a better tribological performance. MoS2 was used as an anti-wear additive that has good tribological sensitivity to the new lubricating base grease.

The main innovative thought of this work lies in the mixture of attapulgite and bentonite used as thickener. A relevant report is not available at present.

This work aims to increase the dyeability of nylon 6 with basic dyeing through the treatment of the fibre with available and cheap nanomaterials, namely; nano bentonite using an economic and simple method.

Different amounts of nano clay, namely, nano bentonite were dispersed in distilled water using an ultrasonic homogenizer for 1 h. Nylon fabrics were treated with different concentrations of dispersed nano bentonite (1%, 2%, 3%, 4%, 5% wt/v). After half an hour, the samples were padded using SVETEMA laboratory padding system. The padding pressure was adjusted at 3 bar to allow a pickup of 100%. The padded samples were dried at 80°C for 5 min and cured at 160°C for 3 min using ROACHES laboratory thermos-fixation. The cured samples were then washed with running water and left to dry at room temperature.

The obtained results indicated that the modification of polyamide 6 fibres with nano bentonite had a great impact on their dyeing properties. The obtained shades, absorption behaviour and fastness properties were significantly enhanced. Based on these results, it was concluded that polyamide fabrics could be successfully dyed with basic dyes using economical dyeing conditions.

This paper introduces a new method the loaded the nano-clay on the synthetic fibres, which are nylon 6 to enhance the dyeability with cationic dyes using the physical method without changing the structure of the fibres.

The purpose of this paper is to evaluate the efficiency of organobentonite (OB) as reinforcing filler in acrylonitrile-butadiene rubber (NBR). The composites were prepared using different loadings of OB and studying in details their properties. A series of OB was modified using surfactant N-cetyl-N, N, N-trimethyl ammonium bromide (CTAB) with concentrations 0.5, 1 and 2 cation exchange capacity (CEC) of bentonite.

The different bentonites were characterized using different analytical and spectro-photometric techniques, such as infra red, X-ray diffraction, thermogravimetric analysis and scanning electron microscopy, while rubber vulcanizate rheological, morphological, swelling and thermal properties were examined using different standard instrumental testing and methods.

The study revealed that the modification of bentonite using CTAB showed significant enhancement on NBR properties, and the optimum filler loading was 12 phr for both 0.5CEC OB and 2CEC OB. These modified bentonites improved reinforcing properties to NBR vulcanizates. Also, results showed that composites exhibited remarkable improvements in tensile strength, elongation at break and hardness in the presence of modified bentonite and also an increase in thermal stability.

Na-B cannot be applied in rubber matrix without modification because it is incompatible with it.

The modified bentonite is considered as efficient reinforcing filler which can replace other fillers because it has lower surface energy and improved intercalating behaviour in rubber matrix.

These papered bentonites are cheap with relatively high purity, which make rubber/clay composites emerge as new class of material and can be used in different fields other than rubber.

Organophilic Sylodex Bentonites are organically treated forms of the clay mineral montmorillonite. The latter is present in the form of microscopically small platelets. The platelets are characteristic of the crystalline structure of the montmorillonite. The chemical composition is that of an aluminium hydrosilicate in which the silicon, aluminium and oxygen atoms are arranged in 3 layers (see Fig. 1). The outer layers consist of SiO2‐tetrahedra and the inner layers of (AlO4(OH)2) octahedra. An idealized initial structure of the precursor of montmorillonite exhibits the following neutral formula:

The purpose of this study is to determine the possibilities to use drill cuttings in soil formation processes on sandy substrates. The ecological and toxicological assessment of drill cuttings of various genesis and mixtures based on them is applied for the purpose.

Acute toxicity of mixtures consisting of various drill cuttings, sand and peat was estimated using soft wheat seeds (Triticum aestivum) using the eluate method. Subacute toxicity experiments were carried out using creeping trefoil (white clover) seeds (Trifolium repens), rye seeds (Secale cereale), and garden radish seeds (Raphanus sativus L.). Drill cuttings of the West Siberian oil-and-gas basin generated as a result of drilling on clay-polymer drilling fluids can be used as a component of soil-like mixtures in the reclamation of sand fills. Patterns of the selective stimulation of seed growth by components of drilling fluids (xanthate and bentonite) were revealed.

It was found that the addition of bentonite and xanthan (0.05% by weight of the cuttings each) reduces the suppression of seed growth occasioned salt content by 21.1% and 24.0%, respectively.

Soil degradation and desertification is a serious and widespread problem. The restoration of the fertile layer can be launched by application of the artificial soil-like mixtures based on drill cuttings of a certain origin to the disturbed lands.

Materials commonly involve microstructure. Clay is a microinhomogeneous material with nanoscale microstructure. Key issues to understand the behavior of such a finely microinhomogeneous material are as follows: the microstructure is characterized in detail, the local distribution of material properties is identified by experiment or simulation, and the microscale characteristics are related to the macroscale behavior by a seamless manner. For characterizing a microstructure of bentonite, we introduce a conforcal laser scanning microscope (CLSM) together with SEM. By CLSM we can specify a 3D configuration under atmospheric condition. Properties of water‐saturated bentonite are mainly controlled by hydrated montmorillonite, which is the major clay mineral of bentonite. Smectite minerals including montmorillonite are extremely fine and poorly crystallized, so it is difficult to determine the properties by experiment. We inquire into the physicochemical properties by a molecular dynamics simulation method. Then, we develop a multiscale homogenization method to extend the microscopic characteristics to the macroscopic behavior. We show numerical examples of a diffusion problem.

The purpose of this paper is to study the corrosion behavior of Q235 steel in the bentonite-based resistance-reducing agent (RRA) with different infiltration rates of underground water.

The corrosion behavior of the steel in underground water was assessed by weight loss experiment, electrochemical impedance spectroscopy and polarization curve.

The results showed that the corrosion rate of the steel in the RRA pastes was much lower than that in the original acidic soil. The underground water infiltration slightly accelerated the corrosion rate of the steel in the RRA pastes, but the acceleration role is weak. The bentonite-based RRA can be compatibly applied in the acidic soil.

The bentonite-based RRA can significantly reduce the corrosion rate of the steel and is suitable to compatibly apply in the acidic soil.

This study aims to motivate the application of some low-cost minerals in synthesizing nanoparticles as effective additives on the performance of liquid crystal (LC) hydroxypropyl cellulose (HPC) nanocomposite film, in comparison with carbon nanoallotrope.

Metallic nanoparticles of vanadium oxide, montmorillonite (MMT) and bentonite were synthesized and characterized by different techniques (Transmission electron microscopy [TEM], X-ray diffraction [XRD] and Fourier transform infrared [FTIR]). While the XRD, FTIR, non-isothermal analysis thermogravimetric analysis, mechanical analysis, scanning electron microscope and polarizing microscope were techniques used to evaluate the key role of metallic nanoparticles on the performance of HPC-nanocomposite film.

The formation of nanoparticles was evidenced from TEM. The XRD and FTIR measurements of nanocomposite films revealed that incorporating the mineral nanoparticles led to enhance the HPCs crystallinity from 14% to 45%, without chemical change of HPC structure. It is interesting to note that these minerals provide higher improvement in crystallinity than carbon nanomaterials (28%). Moreover, the MMT provided film with superior thermal stability and mechanical properties than pure HPC and HPC containing carbon nanoparticles, where it increased the E_a from 583.6 kJ/mol to 669.3 kJ/mol, tensile strength from 2.25 MPa to 2.8 MPa, Young’s modulus from 119 MPa to 124 MPa. As well as it had a synergistic effect on the LC formation and the birefringence texture of the nanocomposites (chiral nematic).

Hydroxylpropyl cellulose-nanocomposite films were prepared by dissolving the HPC powder in water to prepare 50% concentration, (free or with incorporating 5% synthesized nanoparticles). To obtain films with uniform thickness, the prepared solutions were evenly spread on a glass plate via an applicator, by adjusting the thickness to 0.2 mm, then air dried.

These minerals provide higher improvement in crystallinity than carbon nanomaterials (28%), moreover, the MMT and bentonite provided films with superior thermal stability than pure HPC and HPC containing carbon nanoparticles. The mineral nanoparticles (especially MMT nanoclays) had a synergistic effect on LC formation and the birefringence texture of the nanocomposites (chiral nematic).

This study presents the route to enhance the utilization of claystone available in El-Fayoum Province as the precursor for nanoparticles and production high performance LC nanocomposites.

This study presents the route for the valorization of low-cost mineral-based nanoparticles in enhancing the properties of HPC-film (crystallinity, thermal stability, mechanical strength), in comparison with carbon-based nanoparticles. Moreover, these nanoparticles provided more ordered mesophases and, consequently, good synergetic effect on LCs formation and the birefringence texture of the HPC-films.