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A reduced graphene oxide (H-rGO)/TiO2-composite (H-TiO2@rGO) as a catalyst for photocatalytic degradation of rhodamine B (Rh B) and methyl orange (MO) was prepared by hydrothermal treating a dispersant of TiO2 nanoparticles with sizes of 5-10 nm and GO obtained by the Hummers method from coal-based graphite in water. Compared with the M-TiO2@GO and M-TiO2@rGO composites by a wet mixing method, results indicated that the TiO2 nanoparticles in H-TiO2@rGO were uniformly decorated on both sides of rGO sheet, forming a stacked-sheet structure while apparent aggregation of TiO2 nanoparticles was found in both M-TiO2@GO and M-TiO2@rGO. Therefore, H-rGO@TiO2 had the highest catalytic activity towards degradation of Rh B and MO under visible light irradiation among the three, where the incorporation of rGO into TiO2 helps to narrow the band gap of TiO2, inhibit the recombination rate of electron–hole pairs and provide conductive networks for electron transfer.

Two small molecular dispersants (SMD-1 and SMD-2) with different charge densities of phosphate as the adsorption group were synthesised by the reaction of polyetheramine, phosphorous acid and formaldehyde. The structure and molecular weights of these two synthesised phosphated superplasticisers (PSPs) and a commercial polycarboxylate superplasticiser (PCE) were characterised by Fourier transform infrared spectroscopy and gel permeation chromatography. The dispersing, adsorption and hydration behaviours with the addition of potassium sulfate (K2SO4) to the cement paste were also analysed. The experimental results showed that, compared with the conventional comb-shaped PCE, the linear structure of the PSPs provided lower dispersing ability but better fluidity retention. The addition of potassium sulfate had an obvious negative effect on the dispersing ability of PCE, while the effect on the PSPs was slight. The adsorption isotherms indicated that, with the addition of 2 wt% potassium sulfate, the competitive adsorption between sulfate ions and PCE was enhanced: the saturated adsorption of PCE decreased by 10.37%, whereas the PSPs were less affected, with the saturated adsorption of SMD-1 only decreasing by 2.32%. Isothermal calorimetry measurements showed that the PSPs showed excellent retarding ability and could delay the hydration process of cement.

In this present work, nanosize zinc oxide particles were prepared via modest coprecipitation synthesis route. Powder X-ray diffraction pattern was applied for calculating the size of crystallites in the prepared sample. Fourier Transform Infra-Red spectrum established the Zn-O bands at 539 and 433 cm−1 in nano ZnO sample. The structural analysis was done using Scanning Electron Microscopy (SEM) studies for ZnO nanoparticles. Ultrasonicated two step procedure was followed to disperse the produced nanoparticles in the combination of water (60%) and ethylene glycol (40%) to produce ZnO nanofluids with five different particle volume fractions from 0.0125% to 0.1%. To overcome the stability problem and uniform distribution of nanoparticles within the fluid, Cetyl Trimethyl Ammonium Bromide (CTAB) dispersant was added within the suspension while preparation. The investigation results of viscosity, density as well as thermal conductivity at various temperatures showed the enhanced results than the base fluid combination. Huge improvements in thermophysical properties leads the ZnO nanofluid as an alternate working liquid in heat transferring systems.

Polymer nanocomposites which possess outstanding antimicrobial efficacies are potential materials for food packaging applications. Amidst the several biodegradable synthetic polymers, Polyvinyl alcohol exhibits excellent biocompatibility and are very economical. A new hybrid composite based on Polyvinyl alcohol with GO and reduced rGO with Potassium Chloride as salt spacer was synthesized using solvent cast method. The antibacterial activity of the prepared films was explored against Pseudomonas aeruginosa (ATCC 7903) Escherichia coli (ATCC 8739) Campylobacter jejuni (ATCC 29428) Staphylococcus aureus (ATCC 6538). The antifungal activity was studied against Candida albicans (ATCC 10231) Trichodermaharzianum (ATCC 90237) Aspergillus Niger (ATCC 6275). Polymer nanocomposite with GO as dispersant (4 wt%) have shown inhibitory activity with respect to P. aeruginosa, E. coli and C. jejuni. Polymer nanocomposite with rGO as dispersant (4 wt%) have inhibitory activity against E. coli, C. albicans and against P. aeruginosa using well diffusion method.

Porous materials manufactured by freeze-casting are demonstrating potential application as oxygen carriers for the production and purification of hydrogen, or anode material for lithium-ion batteries. However, to obtain the required pore morphology and sufficient mechanical strength, the suspension processing parameters must be controlled. Fe2O3 nanoparticles/camphene suspensions were fabricated using stearic acid as the dispersant agent showing a low-viscosity (130 mPa·s) with a high solid volume fraction (0.3). Suspensions show a shear-thinning behavior according to the Sisko model and a maximum packing fraction of 0.569 estimated from a zero porosity sample. A modified Krieger and Dougherty model was introduced to incorporate the influence of the particle-aspect ratio. The Fe2O3 scaffolds manufactured by freeze-casting shown a gradient pore size along the freezing direction, which was diminished with the solid volume fraction, the compression strength was improved with the pore size reduction and fitted according to the minimum solid area model.

Poloxamers (known by the trade name Pluronic®) are triblock copolymer surfactants that contain two polyethylene glycol blocks and one polypropylene glycol block of various sizes. Poloxamers are widely used as nanoparticle dispersants for nanotoxicity studies wherein nanoparticles are sonicated with a dispersant to prepare suspensions. It is known that poloxamers can be degraded during sonication and that reactive oxygen species contribute to the degradation process. However, the possibility that poloxamer degradation products are toxic to mammalian cells has not been well studied. We report here that aqueous solutions of poloxamer 188 (Pluronic® F-68) and poloxamer 407 (Pluronic® F-127) sonicated in the presence or absence of multi-walled carbon nanotubes (MWNTs) can became highly toxic to cultured cells. Moreover, toxicity correlated with the sonolytic degradation of the polymers. These findings suggest that caution should be used in interpreting the results of nanotoxicity studies where the potential sonolytic degradation of dispersants was not controlled.

The increase of harmful carbon monoxide (CO) caused by incomplete combustion can affect human health even lead to suffocation. Therefore reducing the CO discharged by vehicles or factories is urgent to improve the air quality. The spinel cobalt (II, III) oxide (Co3O4) is an active catalyst for CO abatement. In this study, we tried to fabricate dispersing Co3O4 via the dispersion-precipitation method with acetic acid, formic acid, and oxalic acid as the chelating dispersants. Then, the asprepared samples were calcined at 300 ºC for 4 h to obtain active catalysts, and assigned as Co(A), Co(F) and Co(O) respectively, the amount of the dispersants used are labeled as I (0.12 mole), II (0.03 mole) and III (0.01 mole). For comparison, another CoAP sample was prepared via alkaliinduced precipitation and calcined at 300 ºC. All samples were characterized by X-ray diffraction (XRD), temperature-programmed reduction (TPR), scanning electron microscope (SEM), and nitrogen adsorption/desorption system, and the catalytic activity focused on the CO oxidation. The influence of chelating dispersant on the performance of abatement of CO was pursued in this study. Apparently, the results showed that the chelating dispersant can influence the catalytic activity of CO abatement. An optimized ratio of dispersant can improve the performance, while excess dispersant lessens the surface area and catalytic performance. The series of Co(O) samples can easily donate the active oxygen since the labile Co–O bonding and indicated the preferential performance than both Co(A) and Co(F) samples. The nanorod Co(O)-II showed preferential for CO oxidation, T50 and T90 approached 96 and 127 ºC, respectively. Also, the favorable durability of Co(O)-II sample maintains 95% conversion still for 50 h at 130 ºC and does not emerge deactivation.

Nowadays, 3D polymer-derived silicon oxycarbide ceramics (SiOC) can be fabricated by the stereolithography method successfully. However, due to their intrinsically poor ceramic content and the large thermal shrinkage during the pyrolysis, it is difficult for the bulk 3D polysiloxane precursors to be pyrolyzed into dense 3D-ceramics. Herein, the ceramic content of the photocurable polysiloxane precursors was increased by adding a large amount of SiO2 powders into the low solid content epoxy-acrylic siloxane. After being added with proper dispersant, the viscosity of the high solid loading polysiloxane/SiO2 slurry can reach a proper level. Bulk 3D-silica ceramics with the wall-thickness around 8 mm can be conveniently fabricated from the polysiloxane/SiO2 slurry by stereolithography and a two-step sintering process. The addition of a proper sintering aid NaF can promote the 3D-PSO/SiO2 precursor to be converted into dense and crack-free 3D-silica ceramics with good mechanical proprieties.

Waterborne polyurethane (WPU) and Ag NPs have been applied widely in packaging. However, WPU was susceptible to the contamination due to high moisture absorption, and the stability of Ag NPs in matrix polymers was still low. To resolve this problem, chitosan (CS) was used as the dispersant to synthesize CS/Ag NPs composites in this work, and then they were mixed with WPU to prepare CS/Ag-WPU films. CS macromolecules provided the carriers for Ag NPs with a diameter of about 2.5 nm, and Ag NPs were dispersed stably in WPU. Compared with pure WPU film, as-prepared CS/Ag-WPU films had a higher thermal stability at low temperature, and the crystal size for WPU increased after introducing CS/Ag NPs. Importantly, the water contact angle for CS/Ag-WPU-5 increased to 54.2° from 27.5° implying that the hydrophobicity was improved. In addition, CS/Ag-WPU composites exhibited an excellent inhibitory effect on Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). Antibacterial performances of most samples were improved with the crease of the concentration of CS, and the inhibitory effect on S. aureus was preferred. Therefore, as-prepared CS/Ag-WPU films in this paper have a potential application in antibacterial packaging field.

Magnetic nanoparticles (MNPs) are widely investigated to evaluate their efficacy for therapeutic carriers, biosensors, contrast agents, therapeutic agents (hyperthermia generators), antimicrobial agents, etc., in extracellular space. When MNPs are used for biomedical applications, the nanoparticles are usually dispersed in phosphate buffer saline or body fluids. Bare MNPs tends to agglomerate and aggregate due to high specific surface energy and magnetic dipolar interactions. Further non-specific adsorption of proteins and salts on bare MNPs leads to collapse of colloidal properties. In order to mitigate the above problems, bare MNPs are ligated with biocompatible dispersants for colloidal stability. Majority MNPs are ligated with dispersants such as oleic acid, oleylamine, dopamine derivatives, zwitterionic compounds and polyethylene glycol, to obtain surfactant ligand monolayer on MNPs. Sometimes, polymers are also used as capping agent or encapsulation material. Surfactant monolayer can further be functionalized with therapeutics, proteins, immunoreceptor, etc., for a specific application. Hence one need to understand biocompatible properties, especially cytotoxicity, of nanoparticles with different dispersant monolayers. In addition, biocompatibility testing is also important because the presence of extractable chemical compounds and agents from synthesis process may influence biocompatibility. Cytotoxicity is most sensitive of the biocompatibility tests and is useful for evaluating these types of harmful reactions. Effect of dispersants on cytotoxicity of MNPs are not reviewed in the literature. The effect of various dispersant on cytocompatibility of various MNPs are systematically presented here. Among all, polyethylene glycol polymer is a universal dispersant with high colloidal stability and very low cytotoxicity. Short-chain zwitterionic surfactant ligands are next best dispersants.

In response to food packaging improvements, this study investigates changes in mechanical and thermal barrier properties of pigment-based paper coatings when cellulose nanocrystals (CNC) and cellulose nanofibers (CNF) are added to the formulation. Stable dispersions of all coating components were formed between pH 7–9 (zeta potential > |30 mV|) except CNF, which favored stable dispersions at higher pH. Hydrodynamic diameters (Dh) of CNC and CNF decreased when interacting with calcium carbonate ions (Ca2+ and CO32-); however, latex binder and dispersant diameters were unaffected by the presence of CaCO3 in solution. Thermal barrier performance was quantified by measuring ΔT across coated samples, with and without nanoparticle additives. Both CNC and CNF additives significantly contributed to the ΔT measured, with the best result recorded for 2 wt% CNF, pH 7, and a drying rate of 25 °C/min. This sample recorded 37 ± 6 °C higher than the ΔT for baseline coatings (without additive). Dynamic mechanical analysis (DMA) showed a higher storage modulus for all samples containing CNC and/or CNF compared with the baseline coating, suggesting a material with greater resistance to deformation from applied load. Higher dissipation energy was also observed; however, lower tan delta values suggest improved mechanical properties with both additives.

The GuLF STUDY is investigating health outcomes associated with oil spill-related chemical exposures among workers involved in the spill response and clean-up following the Deepwater Horizon disaster. Due to the lack of dermal exposure measurements, we estimated dermal exposures using a deterministic model, which we customized from a previously published model. Workers provided information on the frequency of contact with oil, tar, chemical dispersants applied to the oil spill and sea water, as well as the use of protective equipment, by job/activity/task. Professional judgment by industrial hygienists served as a source of information for other model variables. The model estimated dermal exposures to total hydrocarbons (THC), benzene, ethylbenzene, toluene, xylene, n-hexane (BTEX-H), polycyclic aromatic hydrocarbons (PAHs), and dispersants in GuLF DREAM units (GDUs). Arithmetic means (AMs) of THC exposure estimates across study participants ranged from 0.9) for most of the substances in oil but were lower for some of the substances in tar. These data were linked to the study participants to allow investigation of adverse health effects that may be related to dermal exposures.

The avoidance and mitigation of energy wastage have attracted increasing attention in the context of global warming and climate change. With advances in materials science, diverse multifunctional materials with high thermal conductivity have shown excellent energy-saving potential. In this study, a hybrid film exhibiting high thermal conductivity with excellent stretchability and washability was prepared. First, a simple surface modification of boron nitride (BN) was performed to realize a modified boron nitride (BNOH) filler. Next, an organic dispersant was synthesized to enhance the dispersion of BNOH and graphene nanoplatelets (GNPs) in the proposed composite. Subsequently, a simple procedure was used to combine the dispersed GNPs and BNOH fillers with thermoplastic polyurethane (TPU) to fabricate a hybrid structure. The hybrid films composed of BNOH–GNP/TPU with a dispersant exhibited a high thermal conductivity of 12.62 W m–1 K–1 at a low filler loading of 20 wt.%. This hybrid film afforded excellent stretchability and washability, as indicated by the very small thermal-conductivity reduction to only 12.23 W m–1 K–1 after 100 cycles of fatigue testing and to 12.01 W m–1 K–1 after 10 washing cycles. Furthermore, the cooling and hydrophobicity properties of the hybrid film were enhanced when compared with neat TPU. Overall, our approach demonstrates a simple and novel strategy to break the passive effect of traditional commercial cooling clothing by combining a high-thermal-conductivity film with an active cooling source to amplify the cooling effect and develop wearable cooled smart clothes with great commercial potential.

Assembly processes in marine microbial communities amended with crude oil and chemical dispersant are poorly understood and even more so when biosurfactants are used. We set up a microcosm experiment in which microbiome structure was analyzed using 16S rRNA gene amplicon sequencing and six null models to better understand and quantify the mechanisms and patterns controlling the assembly of a marine crude oil degrading microbial community in the presence of chemical dispersant or rhamnolipid biosurfactant. Although each null model quantifies different aspects of the community assembly, there was a general agreement that neither purely stochastic nor purely deterministic processes dominated the microbial communities, and their influence was variable over time. Determinism was dominant in the early phase of incubation, while stochasticity was prevalent in the middle and late stages. There was faster recruitment of phylogenetically distant species in the dispersant‐amended community compared to oil‐only or rhamnolipid‐amended communities. This analysis provides important insights of how chemical dispersants and rhamnolipid influence microbial communities' dynamics and identified which groups may be excluded—an important consideration for biodegradation process and oil spill response., Assembly processes in marine microbial communities amended with crude oil and chemical dispersant are poorly understood and even more so when biosurfactants are used. We used a comprehensive set of null models approaches to test traditional macroecological concepts in the context of microbial metagenomics in order to understand and quantify the mechanisms and patterns controlling the complexity of microbial ecology Our results advance the understanding of how chemical and biogenic dispersants affect the ecological processes in marine microbial community response to crude oil.

Kraft lignin is an underutilized material mainly combusted in the pulping industry. Its conversion to value-added products for further end-use applications is limited due to its insolubility in water. In this work, the modification of kraft lignin (KL) was conducted through oxidation and carboxymethylation to generate anionic water-soluble lignin (OKL, and CMKL, respectively). The results indicated that these biopolymers acted as effective dispersants in an aluminum oxide suspension. Subsequently, generated biomaterials were polymerized with acrylamide monomer to generate flocculants (i.e., OKL-AM and CMKL-AM) for the aluminum oxide suspension. The properties of polymers were characterized extensively, and the polymerization of OKL and CMKL with acrylamide increased the molecular weight (Mw) of the biomaterials from 16 × 103 and 28 × 103 to 684 × 103 and 387 × 103 g/mol, respectively. Flocculation studies under stirring revealed that the chord length of aluminum oxide particles increased substantially by treating the suspension with the OKL-AM polymer. The reflocculation analysis provided further insight into the reversibility and high strength of formed flocs. Our results confirmed that by following a one-step reaction, a lignin-based dispersant could be generated, and further polymerizing the biomaterials (i.e., dispersants) would make it a valuable flocculant. This investigation confirms a versatile and environmentally friendly pathway to convert a waste material (i.e., lignin) to a green dispersant and flocculant.

In this study, the relationship between the physicochemical properties of kaolin slurries and their particles produced by spray drying to obtain FCC matrices was discussed. Eight aqueous slurries were prepared with 40 wt.% solids using two types of kaolin (K1 and K2) and sodium silicate solution as the dispersant. Additionally, nitric acid at 5.0 wt.% was used to adjust the pH in the range between 6 and 8. Both kaolin sources were characterized by X-ray diffraction and scanning electron microscopy. The K2 kaolin had a higher crystallinity of kaolinite and smaller particle size in comparison with K1. Likewise, while K2 showed 4 well defined bands of hydroxyl groups in the infrared spectrum at 3688, 3666, 3653 and 3620 cm−1, the K1 IR spectrum consisted of two sharp signals at 3692 cm−1 and 3620 cm−1 and two poorly developed bands at 3666 cm−1 and 3653 cm−1. These features intimately related to their structure were shown to have an effect on the morphology of the particles obtained during the drying process; in the case of the K1 slurries, these led to the formation of microspheres, and on the contrary, from K2 slurries mushroom head shape particles were formed. Furthermore, the average diameter (D50) of the particles increased with the increase of the amount of the binder in the slurry. Thus, the results show that a less crystalline kaolin favors the formation of microspherical particles during the spray drying process that allows a better control of the FCC matrix produced to be used in in-situ zeolite Y crystallization on kaolin particles.

On the cusp of a miniaturized device era, a number of promising methods have been developed to attain large-scale assemblies of micro- and nanoparticles. In this study, a novel method is proposed to firmly capture dispersed microparticles of nominal sizes of 10 μm on a two-dimensional array (1.0 × 1.0 mm2) of through-pores on a surface. This is obtained by dispensing a droplet of the particle dispersion on the pores, which drains by applying a vacuum-driven force at the backside of the pores. The assembled particles are captured on the surface in a reversible way, making them available for direct manipulation and inspection, or subsequent transfer of the particles to a second surface. The relevant process parameters dispersant concentration, dispersant type, particle properties, and pitch distance d, are optimized to obtain (near-)perfect ordered particle arrays. Furthermore, to significantly improve the quality of the particle assembly, washing steps are added to remove excess particles from the surface. Silica or polystyrene (PS) particle assemblies with an error ratio (ER) as low as 0.2% are obtained, demonstrating the universality of the proposed method. For the smallest pitch, d = 1.25 μm, even with optimal process parameters, higher ER-values (=1.1%) are obtained.

Obtaining winter diesel fuel is an expensive and complex process, in which paraffinic hydrocarbons are removed from the fuel. Today, the consumption of winter diesel fuel in Russia has reached its maximum, and the volume produced is not enough to meet the needs of the Russian market. Therefore, obtaining winter diesel fuel from summer grades, by adding a depressant additive, remains relevant. The most common depressants are ethylene vinyl acetate copolymers. The effectiveness of depressant-dispersant additives depends on the fractional and group hydrocarbon composition of diesel fuel. Also, the physicochemical characteristics of the paraffins contained in the fuel play an important roleDuring long-term storage of fuel, depressants do not prevent fuel stratification. Therefore, together with a depressant additive, a paraffin dispersant is used, the composition of such additives includes mainly amides and imides of mono- and dicarboxylic acids. Dewaxol 7801 depressant and dispersant additive is a specially selected composition based on surfactants and copolymers in a hydrocarbon solvent. The use of this additive makes it possible to improve the low-temperature performance of diesel fuel without affecting other properties. From the low-temperature properties of diesel fuel, we have chosen the limiting filterability temperature, since it is this temperature that characterizes the real working conditions. When the maximum filterability temperature is reached, the n-paraffin crystals reach sizes exceeding the pore diameters of the filters, the fuel is not pumped through the fine filters of the high-pressure fuel pump, and the fluidity of the fuel deteriorates. The article shows the effect of Dewaxol 7801, a depressant-dispersant additive, on summer diesel fuel, in various concentrations and when the fuel is heated from 40 to 60 degrees in steps of 10 degrees.

Polypropylene (PP)/poly(benzyl methacrylate) (PBzMA) composite particles were prepared by dispersion polymerization of benzyl methacrylate (BzMA) in the presence of PP particles without a conventional dispersant. The polymerization process yielded a stable emulsion of composite particles with a "currant bun"-like morphology consisting of a PBzMA core and PP bumps, indicating that the PP particles operate as colloidal stabilizers. Conversely, when BzMA was replaced with styrene as the monomer, dispersion polymerization yielded a large amount of aggregates. Finally, a stable emulsion was formed by copolymerizing a small amount of methyl methacrylate (MMA) with styrene. This result suggested that PP must interact with a second polymer to prepare stable composite particles. The surfaces of the PP particles, which are highly hydrophilic due to their carboxyl groups, were involved in the attachment and stabilization of the polymer precipitated in the medium. A film prepared from the obtained PP/PBzMA composite particles was highly hydrophobic and strongly adhesive to a PP sheet.

In this work, highly filled composites made of a commercial polypropylene resin and low melting point Tin particles, up to 50 vol.% in loadings, have been prepared by melt blending process. The introduction of stearic acid (SA), a common dispersant, was investigated in compositions. The developed systems were characterized in terms of dynamic rheological testing. Final results confirmed a reduction of linear viscoelastic domain, by increasing filler loadings, with an effect more emphasized in the presence of SA. Contrary to literature studies, at equal filler content (50%), both moduli resulted to be superior for formulations containing the dispersing agent. A further rheological characterization continued on systems at 30 vol.% of particle loadings for highlighting differences depending on the SA addition. Specific tests were also performed at temperatures above the melting of Tin particles. Finally, optical microscopic analyses were carried out for gaining insight on sample microstructure, in controlled conditions of temperature and shear rate.

In this research, nanoparticles and nanostructured thin films of lead sulfide are synthesized by using physicochemical methods at room conditions or suchlike conditions, at short reaction times; furthermore, is used simple laboratory equipment and a simplified experimental configuration. Both syntheses do not employ, ammonium or ammonia to elaborate PbS. The main used precursors for both processes are lead acetate, as the lead source, polyethyleneimine as the complexing agent, and thioacetamide, as the sulfur source. Acetylacetone has been employed as a dispersant agent to elaborate PbS nanoparticles. While the sodium hydroxide maintains a high pH, to elaborate PbS thin films. The characterizations reveal the existence of PbS nanoparticles whose size is smaller than 10nm and with a band gap of 3.35 eV. On the other hand, the resulting thin film is made up of PbS little crystallites of 22 nm in a homogeneous way and its band gap is 1.85 eV.

It remains a great challenge to prepare polylactic acid (PLA) composites with excellent mechanical properties, superior anti-bacteria, and highly effective electromagnetic interference (EMI) shielding using ultralow loading of functional fillers. Herein, lignin particles were uniformly nano-sized as the matrix reinforcement and the fillers carrier via green mechanochemistry for improved thermal properties of polymer matrix. Through one-pot approach to a multitasking engineered agent, hybridized ZnO/Ag particles were synthesized for multi-functionalities. Inspired by mussels, the bio-derived dopamine cross-linker was introduced to in-situ synthesize the polypyrrole (PPy-PDa) glutinous nanofibrils as an interfacial modifier and a particles dispersant to regulate surface free energy of nanoparticles and improve filler-matrix interactions. With effective constructed 3D conductive networks by glutinous nanofibrils and hybridized particles, the dramatic improvement in EMI shielding and electrical conductivity was accomplished using an ultralow content of the conductive particles modifier (0.29 vol% Ag). The resulted biobased composites presented outstanding anti-dripping properties, mechanical properties, electrical conductivity (104.2 S/cm), anti-bacteria, joule heating, photothermal conversion ability and EMI shielding effectiveness (48.6 dB at X-band), which are superior to those reported. This work will broaden the application prospects of PLA composites in the fields of wearable electronics, food packaging and medical devices.

In this study, two types of carbon nanotubes were used as ophthalmic material, and hydrogel contact lenses were polymerized by adding two types of dispersants to effectively exert the functions of carbon nanotubes. The physical properties and surfaces of the ophthalmic hydrogel lenses prepared to confirm the functionality as a dispersant were compared and analyzed to find the utility as an ophthalmic lens material. For the polymerization, single-walled carbon nanotubes (SWCNTs), single-walled carbon nanotubes carboxylic acid functionalized (SWCCNTs), 2-hydroxyethyl methacrylate (HEMA), ethylene glycol dimethacrylate (EGDMA, a crosslinking agent), and azobisisobutyronitrile (AIBN, an initiator) was used. In addition, as a dispersant, PVP (polyvinylpyrrolidone) and BYK-111 were copolymerized. As a result of this study, PVP increased the water content and decreased refractive index regardless of the type of carbon, whereas BYK-111 did not show a significant difference in basic properties. Also, PVP gradually decreased breaking strength, while BYK-111 gradually increased breaking strength. BYK-111 effectively exerted the function of carbon nanotubes, and it was confirmed whether it was dispersed through TEM. Therefore, if carbon nanotubes are used as ophthalmic materials by utilizing BYK-111, it considered to be used as functional ophthalmic lens materials.

Herbicides based formulations are conventionally used as wettable powder or as Emulsifiable concentrate. The Emulsifiable Concentrates (EC) are prepared by mixing the active content with solvents a...

The bactericidal properties of copper oxide nanoparticles have growing interest due to potential application in the medical area. The present research investigates the influence of sodium dodecyl sulfate (SDS) and poly(vinylpyrrolidone) (PVP) on the production of copper oxide nanoparticles prepared from copper sulfate (CuSO4) and sodium borohydride (NaBH4) solutions. Different analytical techniques were used to determine the crystal nature, mean size diameter, and surface morphology of the copper oxide nanoparticles. The X-ray diffraction (XRD) patterns showed formation of nanoparticles of cuprite (Cu2O) and tenorite (CuO) when PVP and SDS were added at the beginning of the reaction. In fact, when the Cu/PVP ratio was 1.62, Cu2O nanoparticles were obtained. In addition, nanoparticles of CuO were synthesized when the Cu/PVP ratios were 0.54 and 0.81. On the other hand, a mixture of copper oxides (CuO and Cu2O) and cuprite (Cu2O) was obtained when PVP (Cu/PVP = 0.81 and 1.62) and SDS (Cu/SDS = 0.90) were added 30 min after the beginning of the reaction. Transmission electron microscopy (TEM) images show agglomerated nanoparticles with a size distribution ranging from 2 to 60 nm, while individual particles have sizes between 4.1 ± 1.9 and 41.6 ± 12.8 nm. The Kirby-Bauer method for the determination of antibacterial activity shows that small CuO (4.1 ± 1.9 nm) and Cu2O (8.5 ± 5.3 nm) nanoparticles inhibit the growth of Escherichia coli, Staphylococcus aureus MRSA, S. aureus and Pseudomonas aeruginosa bacteria. The antibacterial test of cotton fabric impregnated with nanoparticles shows positive results. The determination of the optimal ratio of copper oxide nanoparticles per cm2 of fabric that are able to exhibit a good antibacterial activity is ongoing.

Marine oil dispersants typically contain blends of surfactants dissolved in solvents. When introduced to the crude oil-seawater interface, dispersants facilitate the breakup of crude oil into droplets that can disperse in the water column. Recently, questions about the environmental persistence and toxicity of commercial dispersants have led to the development of "greener" dispersants consisting solely of food-grade surfactants such as l-α-phosphatidylcholine (lecithin, L) and polyoxyethylenated sorbitan monooleate (Tween 80, T). Individually, neither L nor T is effective at dispersing crude oil, but mixtures of the two (LT blends) work synergistically to ensure effective dispersion. The reasons for this synergy remain unexplained. More broadly, an unresolved challenge is to be able to predict whether a given surfactant (or a blend) can serve as an effective dispersant. Herein, we investigate whether the LT dispersant effectiveness can be correlated with thermodynamic phase behavior in model systems. Specifically, we study ternary "DOW" systems comprising LT dispersant (D) + a model oil (hexadecane, O) + synthetic seawater (W), with the D formulation being systematically varied (across 0:100, 20:80, 40:60, 60:40, 80:20, and 100:0 L:T weight ratios). We find that the most effective LT dispersants (60:40 and 80:20 L:T) induce broad Winsor III microemulsion regions in the DOW phase diagrams (Winsor III implies that the microemulsion coexists with aqueous and oil phases). This correlation is generally consistent with expectations from hydrophilic-lipophilic deviation (HLD) calculations, but specific exceptions are seen. This study then outlines a protocol that allows the phase behavior to be observed on short time scales (ca. hours) and provides a set of guidelines to interpret the results. The complementary use of HLD calculations and the outlined fast protocol are expected to be used as a predictive model for effective dispersant blends, providing a tool to guide the efficient formulation of future marine oil dispersants.

Zirconium oxide (ZrO2) nanoparticles were synthesized and used as additives to prepare silicone oil-based nanofluids. The stability issues associated with the nanofluid are overcome by using oleic acid (OA) as a dispersant. Thermal conductivity and viscosity measurements were carried out at temperature range (25–45 °C). Thermal conductivity of ZrO2/silicone oil nanofluid shows nonlinear behaviour with increasing concentration of ZrO2 nanoparticles. Viscosity measurements showed 31.1% enhancement for 0.1 volume fraction of ZrO2 in OA incorporated ZrO2 nanofluid. The thermal conductivity and viscosity increment of OA incorporated ZrO2/silicone oil nanofluid predict it for cutting fluid applications.

Reticulated porous ceramics feature a three-dimensional network structure with high porosity and permeability simultaneously. However, generally, the compressive strength capabilities of reticulated porous ceramics are low, which severely limits applications of these materials. To increase the compressive strength of reticulated porous ceramics, it is necessary to coat the strut walls of the polyurethane foam completely with alumina slurry to form a thin ceramic coating layer after optimizing the processing conditions, specifically the alumina slurry composition and the coating condition. Although it remains challenging to improve the compressive strength of reticulated porous ceramics, thus far efforts to do so are underreported. Therefore, in this study, we attempt to optimize the composition (thickener, dispersant, and binder) of the alumina slurry. Among various types of reticulated porous ceramics, we focus on reticulated porous alumina here. Although there are numerous studies regarding porous alumina, which is already widely used, investigations of reticulated porous alumina are rare. In this study, we determined the optimized processing conditions to improve the compressive strength of reticulated porous alumina. These conditions, specifically the composition of the alumina slurry and the pore density of the polyurethane foam, are discussed.

In this article, we synthesized a series of poly butyl acrylate-co-methacrylic acid-2-acrylamido-2-methyl propanesulfonic acid (PBAS) with different molecular weight and monomer molar ratios by 1,1...

Six different sodium lignosulfonates with varying degrees of sulfonation (0.14–1.29 sulfonate groups per phenylpropane unit) and molecular weights (Mw = 6000–330,000 g/mol) were evaluated for their ability to disperse carbon black in aqueous media. Rheological and particle size measurements of carbon black dispersions indicated that lignosulfonates with low degree of sulfonation function as good carbon black dispersants. The dispersion efficiency did not correspond directly to the amount of lignosulfonate adsorbed on the surface of carbon black. The lignosulfonates have an ability to enhance the colloidal stability by electrostatic repulsion, and the likely mechanism of stabilization is a combination of electrostatic repulsion and steric hindrance. Graphical abstract

This work probes the slurry architecture of a high silicon content electrode slurry with and without low molecular weight polymeric dispersants as a function of shear rate to mimic electrode casting conditions for poly(acrylic acid) (PAA) and lithium neutralized poly(acrylic acid) (LiPAA) based electrodes. Rheology coupled ultra-small angle neutron scattering (rheo-USANS) was used to examine the aggregation and agglomeration behavior of each slurry as well as the overall shape of the aggregates. The addition of dispersant has opposing effects on slurries made with PAA or LiPAA binder. With a dispersant, there are fewer aggregates and agglomerates in the PAA based silicon slurries, while LiPAA based silicon slurries become orders of magnitude more aggregated and agglomerated at all shear rates. The reorganization of the PAA and LiPAA binder in the presence of dispersant leads to a more homogeneous slurry and a more heterogeneous slurry, respectively. This reorganization ripples through to the cast electrode architecture and is reflected in the electrochemical cycling of these electrodes.

In this study, low-rank coal-water slurry (LCWS) was prepared using polyoxyethylene dodecylphenol ether (PDPE) and polyoxyethylene lauryl ether (PLE), respectively. A combination of experiments and simulations was used to investigate the pulping properties and microscopic mechanism of the LCWS samples prepared using the two agents, so as to explore the influence of benzene ring on the performance of dispersant. The results of the LCWS preparation experiments revealed that the pulp-forming performance of PDPE exceeded that of PLE. When LCWS concentration is 62%, 64%, and 66%, the apparent viscosity corresponding to PDPE is 247.80, 504.17, and 653.10 mPa·s, and the apparent viscosity corresponding to PLE is 548.10, 1470.61, and 1549.98 mPa·s, respectively. The C1000 (When the apparent viscosity is 1000 mPa·s, the corresponding concentration of LCWS is defined as C1000) values of PDPE and PLE are 67.60% and 62.95%, respectively. In addition to the van der Waals forces and hydrogen bonds between the PDPE and/or PLE molecules and coal, the benzene rings of PDPE present π-π stacking effect with the aromatic rings of coal. That could facilitate and strengthen the adsorption of PDPE on coal, which would be conducive to further improving the dispersion of coal particles. The two dispersants have no significant difference in effect on the pyrolysis of LCWS. The simulation results indicated that the times for PDPE and PLE molecules to reach flat adsorption state on coal are approximately 290 and 565 ps, respectively. The self-diffusion coefficient (D) of the PDPE and PLE on coal is 3.16 × 10−6 and 6.57 × 10−6 m2/s, respectively, and their interaction energies with coal are 785.71 and 648.60 kcal/mol, respectively. The results of the simulation calculations demonstrated that PDPE adsorbed on coal easier than PLE, and its binding is more stable than that of PLE owing to the π-π stacking effect, which is conducive to uniform dispersion of coal in solution. The simulation results confirmed the experimental results.

With the increasing awareness of environmental protection and energy conservation, ink-jet printing technology has attracted much attention in recent years. In this work, attempts have been made to prepare novel dye-based inks for printing wool/acrylic blend fabrics using cationic reactive dyes in ink’s formulation. After the dyes were milled, various auxiliaries were added into dye dispersion solution. The effect of dispersant, polyols, surfactants, and pH regulator on ink properties has been investigated to obtain the optimum condition of each ink. The stability of inks was also measured. Then the wool/acrylic blend fabrics were digitally printed and the color performance as well as color fastness of printed fabrics were also studied. Experimental results showed that all the auxiliaries had significant impact on properties of inks. The optimal formulations for inks as following: cationic reactive dyes were 10 % w/w, dispersant (dispersant IW) was 25 % w/w, polyols (ethylene glycol) was 15 % w/w, surfactant (XP-70) was 1.5 % w/w, and pH regulator (triethanolamine) was 0.02 % w/w. Except for Dye 3 (D3)-based ink, the other three inks showed satisfactory storing stability in 90 days. Additionally, the wool/acrylic blend fabrics printed with Dye 1 (D1), Dye 2 (D2), Dye 4 (D4)-based inks exhibited excellent union color properties and color fastness.

The present work describes a comparative study on a pool of 12 dispersants for the de‐agglomeration and stabilization of silicon carbide in aqueous suspensions with solids loading relevant for dip coating applications. As silicon carbide slurries may include sintering aids, different functional groups, molecular weight, and stabilization mechanisms were considered for the dispersants to be able to stabilize both slurry components. Additionally, pH effect, toxicity, additive compatibility, and foaming properties were considered, giving all the necessary information for developing new aqueous formulation of SiC suspensions, including advantages and disadvantages of the different candidates. Different de‐agglomeration procedures, powder surface area and calcination temperature are also considered to study the effect of the SiC surface properties.The outcome is that slurry stabilization provided by an alkaline environment at pH larger than 8‐9 is significantly more effective than slurry stabilization by any of the tested dispersants. Alkaline environments facilitate a negative surface charge on SiC particles and provides a stable electrostatic stabilisation mechanism not observed in neutral or acidic environments. One among the dispersant candidates (FA 4404) seems to broaden slightly the range of stability towards the acidic regime. Anionic surfactants or block co‐polymers tested exhibited no significant interaction with the SiC particles.

New Sn-Ti microspheres were first successfully synthesized by a PVP-assisted sol-gel method in this paper, and their performance in the B–V oxidation of cyclohexanone was investigated. The XRD, N2 sorption, SEM, Py-IR, UV–Vis, XPS, EDX, Elemental mapping and TEM characterization techniques were utilized to investigate their physical and chemical properties. Based on the proposal possible formation mechanism, in the MTS-x sample synthesis procedure, the introduction of PVP as a stabilizer and dispersant can coordinate the hydrolysis rate of two different precursors resulting in the hindrance of their agglomerations. And the HDA as a precipitation accelerator and morphology control agent can be beneficial to the formation of spheres by increasing the hydrogen-bonding interactions. The MTS-12 as well as the weight percent of tin to titanium species of 12 with specific regular microspheres has the highest cyclohexanone conversion of 97.8% and the highest e-caprolactone selectivity of 98.2%, which is better than the bulk Sn-TiO2 catalyst even though that the weight percent of tin to titanium species was 18. The catalysts with higher accessible active sites and shorter diffusion channels would provide a valuable theoretic reference for the industrial process of the B–V oxidation of cyclohexanone for the preparation of caprolactone.

The preparation of aqueous graphene nanoplatelet (GNP) dispersions is a challenging task due to their tendency to agglomerate. In contrast, graphene oxide (GO), an oxidized form of GNP, has amphiphilic characteristics which allow it to disperse in an aqueous milieu without the addition of a surfactant. Therefore, we utilize GO as a dispersing agent to prepare highly-concentrated aqueous GNP dispersions, which can be used for various applications. The nature of the dispersed phase is investigated by various material characterization methods. Furthermore, we measure the zeta potentials of the dispersed phased as well as the contact angles of dispersions on different substrates. The latter data are used in the extended Derjaguin–Landau–Verwey–Overbeek theory to gain insight into the interactions that determine dispersion stability. We find that the stability of such dispersions mainly depends on the pH value as well as the ratio of GO and GNP concentrations. The rheology of the dispersions is investigated and different nematic phases are identified. Finally, highly-concentrated dispersions are used for printing of graphene films on a flexible substrate. After reduction of the minor GO fraction, the films have a high conductivity of more than 4500 S m−1.

Flower-like ZnO microstructures were successfully produced using a hydrothermal method employing ZnSO4/(NH4)2SO4 as a raw material. The effect of the operating parameters of the hydrothermal temperature, OH−/Zn2+ molar ratio, time, and amount of dispersant on the phase structure and micromorphology of the ZnO particles were investigated. The synthesis conditions of the flower-like ZnO microstructures were: hydrothermal temperature of 160°C, OH−/Zn2+ molar ratio of 5:1, reaction time of 4 h, and 4 mL of dispersant. The flower-like ZnO microstructures were comprised of hexagon-shaped ZnO rods arranged in a radiatively. Degradation experiments of Rhodamine B with the flower-like ZnO microstructures demonstrated a degradation efficiency of 97.6% after 4 h of exposure to sunshine, indicating excellent photocatalytic capacity. The growth mechanism of the flower-like ZnO microstructures was presented.

The features governing the high-rate thermal transformation (combustion without air access) of several dispersants (high-enthalpy N-heterocyclic compounds) were experimentally studied. The quantitative regularities of the combustion of both individual dispersants and their mixtures with isoprene rubber and ammonium perchlorate were examined. The dependences of consumption of individual dispersants on the nitrogen pressure, enthalpy of formation of the dispersants, and oxygen supply coefficient of the dispersant were determined. The dependences of the combustion rate on the contents of isoprene rubber and ammonium perchlorate were experimentally determined for the fuel compositions based on each dispersant. The results of the study can be used for the formation of optimal gas-generating fuel compositions.

The current study presents an attempt to develop two molecules, namely sulfonated aromatic diol (SAD) and sulfonated aromatic diamine (SADAM), to induce flame retardancy, thermal stability, and dispersion ability for water-based polyurethane dispersions (WPUDs). The previously reported itaconic acid-based polyester polyol was used for prepolymer synthesis as well as for chain extension. Pre- and post-sulfonated compounds were subjected to characterization tests such as FTIR, 13C-NMR, 1H-NMR, and CHNS for confirmation of their structures. The standard dispersant used for the basis of comparison was commercially available dimethyl propionic acid (DMPA). WPUDs were synthesized in different molar concentrations of DMPA, SAD, and SADAM, and the covalent incorporation of all three molecules in the polymer backbone was confirmed by FTIR. The WPUD films were subjected to various thermal tests like TGA and DSC as well as mechanical tests like flexibility and pencil hardness. WPUD films obtained from SADAM showed a remarkable increase in Tg as well as char content. The THRI values for SAD- and SADAM-based films were better than DMPA-based films. SAD- and SADAM-based WPUD films also showed an increase in LOI value and UL-94 ratings with the maximum LOI value of 26. Dispersions based on DMPA showed better stability as compared to dispersions based on SAD and SADAM.

In this research, the effect of different parameters on the behavior of suspension rheology, as well as the physical and mechanical properties of green and sintered SiC bodies, were investigated. Viscosity values ​​for slurries containing 0.1, 0.3, 0.5, 0.7, 0.9 and 1.1 wt% of dispersant (Tetramethyl ammonium hydroxide ((CH3)4NOH, TMAH) were investigated, and the minimum viscosity was obtained for the slurry containing 0.7 wt% TMAH. The results showed that the highest amount of SiC powder that could be used without causing any serious problem was 37 vol.%. The monomers used in the research were metacrylamide (MAM) and N,Ń- methylenbisacrylamide (MBAM). Afterward, the effect of monomers content (MAM and MBAM) and ceramic load on the shrinkage and warpage of green bodies were investigated. The results demonstrated that increasing the amount of monomers decreases warpage rate (WP) and shrinkage rate (SK). Other than that, with increasing monomers ratio, both of these parameters increase uniformly. Subsequently, the samples were sintered for 1 h at 2150 °C. The results proved that the sample containing 37 vol.% of SiC with a monomers ratio of 3:1 and a total monomers content of 20 wt.% had the highest hardness, fracture toughness, and relative density, equal to 27.51 ± 1.25 GPa, 6.2 MPa.m1/2, and 96.89%, respectively.

Rigid polyurethane foams (RPUF) are the most consumed cellular polymer in the world. Bio-based polyols are sometimes used as raw material for RPUF but with a detrimental effect on mechanical properties. In this paper, micro fibrillated cellulose (MFC) was used as a reinforcement to enhance the mechanical, thermal and dynamic mechanical properties of bio-based RPUF. A bleached Eucalyptus sp. pulp was dispersed in glycerine and then subjected to mechanical defibrillation to extract the MFC, a route that does not require dispersants or drying, which is advantageous for the MCF incorporation. The RPUF were manufactured in a closed mould in a way to obtain overpacking. The higher the overpacking degree, the higher the apparent density and stiffness of the RPUF. Also, expansion under confinement yielded more rounded polymer cells with decreased anisotropy. The MFC and overpacking acted synergistically, improving strength, stiffness, thermal stability and dynamic mechanical properties of the RPUF. Thermal conductivity of the RPUF, on the other hand, was unaffected by those factors.

Gulf of Mexico (GOM) ecosystems are interconnected by numerous physical and biological processes. After the Deepwater Horizon (DWH) disaster, these ecological processes facilitated dispersal of oil-spill toxicants or were damaged and broken. A considerable portion of post-DWH research focused on higher levels of biological organization (i.e., populations, communities, and ecosystems) spanning at least four environments (onshore, coastal, open ocean, and deep benthos). Damage wrought by the oil spill and mitigation efforts varied considerably across ecosystems. Whereas all systems show prolonged impacts because of cascading effects that impacted functional connections within and between communities, deep-sea and mesopelagic environments were particularly hard hit and have shown less resilience than shallow environments. In some environments, such as marshes or the deep-sea benthos, products from the spill are still biologically accessible. Some shallow ecosystems show signs of recovery, and populations of some species show resilience; however, a return to a “pre-spill” state is questionable. Importantly, habitats in which large amounts of energy flow through the ecosystem (marshes, coastal regions) recovered more quickly than low energy habitats (deep-sea benthos). Functional interactions between Gulf of Mexico systems are more complex and widespread than generally recognized. Moreover, ecosystems in the Gulf are subject to multiple stressors that can combine to impart greater, and less predictable, impacts. To help mitigate the effects of future insults, we identified four salient areas of research that should be addressed for each of the major environments within the GOM: establishing monitoring systems; quantifying coupling between GOM ecosystems; developing criteria for assessing the “vulnerability” and “resilience” of species, communities, and ecosystems; and developing holistic predictive modeling.

A direct preparation method for a powdered geopolymer was developed using polyvinyl alcohol as a dispersant template. Metakaolin obtained by calcination of kaolinite at 600 or 750°C was used as silica-alumina source. Powdered samples with average particle sizes of 44.2 and 42.0 µm were prepared from the metakaolin calcined at 600 and 750°C, respectively. The sample prepared from metakaolin calcined at 750°C consisted of geopolymer, while the sample prepared from metakaolin calcined at 600°C consisted of a mixed phase of unreacted metakaolin and geopolymer. The sample prepared from metakaolin calcined at 750°C showed higher Cu(II) cation adsorption ability. The adsorption amount of Cu(II) cation was 40.8 mg/g, which is comparable to the adsorption capacity of the geopolymer prepared by the conventional method.

The morphology effect of cerium oxide (CeO2) has always been the focus of catalysis research. Few people have reported the relationship between the morphology of CeO2 and electrochemical performance in sensors. In this paper, a polyaniline (PANI) matrix is used as the dispersant and stabilizer, ultrafine Au nanoparticles (NPs) (Au@PANI) are uniformly embedded in the PANI matrix, and Au NPs@PANI is fixed on the surface of CeO2 with different morphologies and sizes (Spindle CeO2:(SCe), octahedron CeO2 (OCe)). The morphology and crystal structure of CeO2 were adjusted under different ratios of ethanol and water, and the effect of CeO2 was evaluated. The synthesized CeO2-Au@PANI has different morphologies, sizes, and electrochemical properties. The electrochemical catalytic behavior of CeO2-Au@PANI was studied by using hydrogen peroxide (H2O2) as the reaction substrate. The instantaneous current method (I-T) was used to further study the electrochemical amplification effect, and the best performance was obtained.

Inkjet printing is a promising alternative for the fabrication of thin film components for solid oxide fuel cells (SOFCs) due to its contactless, mask free, and controllable printing process. In order to obtain satisfying electrolyte thin layer structures in anode-supported SOFCs, the preparation of suitable electrolyte ceramic inks is a key. At present, such a kind of 8 mol% Y2O3-stabilized ZrO2 (8YSZ) electrolyte ceramic ink with long-term stability and high solid loading (> 15 wt%) seems rare for precise inkjet printing, and a number of characterization and performance aspects of the inks, such as homogeneity, viscosity, and printability, should be studied. In this study, 8YSZ ceramic inks of varied compositions were developed for inkjet printing of SOFC ceramic electrolyte layers. The dispersing effect of two types of dispersants, i.e., polyacrylic acid ammonium (PAANH4) and polyacrylic acid (PAA), were compared. The results show that ultrasonic dispersion treatment can help effectively disperse the ceramic particles in the inks. PAANH4 has a better dispersion effect for the inks developed in this study. The inks show excellent printable performance in the actual printing process. The stability of the ink can be maintained for a storage period of over 30 days with the help of initial ultrasonic dispersion. Finally, micron-size thin 8YSZ electrolyte films were successfully fabricated through inkjet printing and sintering, based on the as-developed high solid loading 8YSZ inks (20 wt%). The films show fully dense and intact structural morphology and smooth interfacial bonding, offering an improved structural quality of electrolyte for enhanced SOFC performance.

The efficiency of using seven cubane derivatives as dispersing components of solid generator propellants was studied. With cubane, bicubyl, or 1,4-dicubylbenzene used as a propellant dispersant, the aerial vehicle range can be increased to the level considerably exceeding the range reached with other compounds considered for this purpose previously. The use of nitro derivatives of cubane such as 1,4-dinitrocubane, 1,3,5,7-tetranitrocubane, 1,2,3,5,7-pentanitrocubane, and 4-bis(nitroxymethyl)cubane ensures somewhat shorter range than that reached with cubane, bicubyl, or 1,4-dicubylbenzene, but this range is still somewhat longer than when using furazan derivatives as dispersants.

The dispersion effect of degraded cellulase from Bacillus methlylotrophicus Y37 and sodium dodecyl sulphate (SDS) together on copper(II) phthalocyanine (CuPc) pigment is studied for the first time ...

In this study, Alkenyl succinimides with different alkyl chain lengths were synthesized using polyisobutylene (PIB) with the molecular weights of 1000 and 1300, which displayed the best functional properties. The secondary amines found in b-Polyisobutylene succinimide (b-PIBSI) dispersants were prepared by attaching PIB chains to a polyamine core via two succinimide moieties. In this work, detergent/dispersant type additives were synthesized based on polyisobutylene succinic anhydride (PIBSA) and its aminated compounds (PIBSI) with tetraethylenepentamine (TEPA). The resulting PIBSA and PIBSI characterized by Fourier transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance (1H-NMR), and gel permeation chromatography (GPC) spectroscopies were greatly complicated because of the interactions between the carbonyls of the succinimide groups and unreacted secondary amines of the Mb-PIBSI dispersants. The viscoelasticity of obtained PIBSI indicated the increase in storage modulus with time which illustrated the increase in the solid-like properties of PIBSI. Therefore, an alternative procedure was developed based on fluorescence quenching of the succinimides by secondary amines and urethane groups.

Poor cold flow property is a major issue that hinders the application of biodiesel-diesel blends. In this work, a series of methacrylate-benzyl methacrylate-N-vinyl-2-pyrrolidone terpolymers (RMC-MB-NVP, R= C12, C14, C16, C18) was synthesized and used as the pour point depressants (PPDs) for waste cooking oil biodiesel blends. To further improve their depressive effects, dispersants, including Tween (40, 60, and 80), Span (40, 60, and 80), phthalic acid esters (PAEs), and fatty alcohol polyoxyethylene ether (FAPE; FAPE 5, FAPE 7, and FAPE 9), were optimized and combined with the C14MC-MB-NVP terpolymers. The effects of C14MC-MB-NVP terpolymers and combined PPDs (PPDC) on the cloud point (CP), cold filter-plugging point (CFPP), and pour point (PP) of biodiesel blends were studied. Here, results showed that the presence of dispersants can efficiently enhance the solubility and dispersibility of polymeric PPDs in biodiesel blends; thus, the PPDC presents better depressive effects. Among of them, C16MC-MB-NVP (5:1:1) combined with FAPE 7 dispersant at 4:1 mass ratio (PPDC-FAPE 7) showed the best synergistic effect, and the CP, CFPP, and PP of B20 treated with 2000 ppm PPDC-FAPE 7 decreased by 4, 10 and 19 °C, respectively. Moreover, differential scanning calorimetry, polarizing optical microscope and rheological analyses were performed to rationalize the action mechanism of these PPDs and dispersants in biodiesel blends.