Effect Of Sodium Polyacrylate Research Articles

Effect of a nonionic surfactant and anionic polyelectrolyte binary system on the stability of a calcium and magnesium carbonates dispersion

The effect of sodium polyacrylate, polyethylene glycol of various molecular weights, and their mixtures on the dispersion stability of calcium and magnesium carbonates was studied. It was shown that in the presence of a binary system, the light transmission of the dispersion decreases 1.2–1.5 times, the content of fine fraction particles increases by 1.1–1.3 times compared to the individual components. The stability of the dispersion of carbonates depends on the components ratio in the binary system and their molecular weight. The formation of adsorption solvated layers of polyacrylate and polyethylene glycol molecules at the interphase boundary contributes to an increase in the stability of the carbonate dispersion.

The flotation of fine hematite by selective flocculation using sodium polyacrylate

• Fine hematite was separated from fine quartz by PAAS flocculation flotation . • The hematite particle size increased by 52% due to PAAS selective flocculation. • The adsorption mechanism of PAAS on the hematite surface was discussed in detail. Fine hematite and quartz are particularly difficult to separate using classic flotation and magnetic separation methods because the particles were very small and readily reported to the wrong product. The effect of sodium polyacrylate (PAAS) on the flotation separation of fine hematite from quartz and its mechanism were investigated by micro-flotation experiments using NaOL as a collector, particle size analysis, zeta potential measurements, FT-IR, SEM analysis as well as XPS analyses. The flotation tests found that the flotation recovery of fine hematite increased observably to 94.51% from 68.69% by adding 4 mg/L PAAS before NaOL at pulp pH 7.3; in the separation of mixed hematite and quartz, the separation efficiencies of fine hematite with and without the addition of the PAAS are 85.71% and 68.84%, respectively. After treatment with the PAAS, the fine hematite was well flocculated so that the average hematite particle size increased to 26.73 μm from 17.69 μm, and the particle size distribution of hematite less than 17 μm decreased to 29.58% from 52.51%. Zeta potential variations indicate that the collector NaOL is able to adsorb on the hematite surface after flocculation by the flocculant PAAS whereas the adsorption of the PAAS on quartz plays an inhibitory role in the adsorption of collector NaOL on the quartz surface, considerably improving the floatability of fine hematite, and thus realizing the effective separation of fine hematite from fine quartz. Furthermore, FT-IR, SEM, and XPS analyses suggest that the flocculant PAAS adsorbs on the hematite surface in a scattered punctiform morphology via a chemical bond in which the Fe 3+ of the hematite surface reacts with the –COO – of PAAS to form dimers, including (RCOO) 2 2– or RCOOH-RCOO - .

Efecto del poliacrilato de sodio (PANa) en la supervivencia e incremento dasométrico de dos especies forestales durante dos años en campo

La problemática del uso de suelos de aptitud forestal en las regiones áridas y semiáridas presenta escasez de lluvias y baja calidad de suelos, por ello, es importante buscar alternativas que permitan superar estos inconvenientes. El presente tiene como objetivo evaluar el efecto del Poliacrilato de Sodio (PANa) de pañales desechables usados en la supervivencia y crecimiento dasométrico de dos especies forestales, durante dos años en campo. Para lo cual se establecieron plantaciones de Pinus radiata D. Don y Polylepis incana bajo tres tratamientos de Poliacrilato de sodio, se evaluó el incremento dasométrico y el porcentaje de supervivencia cada seis meses durante dos años. Para el análisis de las variables se utilizó el diseño estadístico multifactorial. Los resultados indican que el mayor incremento de la altura y diámetro se dio en ambas especies forestales que fueron reforestadas bajo el tratamiento 2 y tratamiento 3, el mayor porcentaje de supervivencia en P. radiata se presentó en el tratamiento B, mientras que en P. incana el testigo presento el mayor porcentaje de supervivencia.

Enhancing flotation separation of chalcopyrite and magnesium silicate minerals by surface synergism between PAAS and GA

Separation effects of sodium polyacrylate (PAAS) and gum Arabic (GA) on flotation of chalcopyrite and magnesium silicate minerals using potassium butyl xanthate (PBX) as collector were investigated by micro-flotation experiments, zeta potential, Infrared spectral (IR), SEM–EDS, XPS analysis and copper sulphide ore beneficiation test. The micro-flotation experiments and zeta potential measurements showed that combined depressant consisting of PAAS and GA could efficiently reduce the recoveries of mixed minerals of serpentine and talc more than 25%, while that of chalcopyrite remained above 70% at pH 9.2. Infrared spectral (IR), SEM–EDS and XPS analysis showed that PAAS chemically reacted with Mg on the surface of serpentine, while GA adsorbed on talc surface mainly via physical interaction and hydrogen bond may also play a role. Surface synergism between PAAS and GA was investigated by turbidity test and its depression mechanism was proposed. The technology feasibility of using PAAS and GA to improve the copper sulphide ore flotation performance was verified through artificial mixed ore flotation and laboratory closed-flotation operation.

Inhibition of calcium and magnesium carbonate crystallization with sodium polyacrylate

It is known that when water are used for technological purposes, in circulating water supply systems of enterprises as a coolant during continuous heating and cooling, the formation of insoluble precipitates, most often calcium carbonates, occurs on the walls of heat exchangers, which leads to a large number of problems, even production can be stopped for cleaning equipment. To prevent the formation of salts, it is necessary to use precipitation inhibitors. Sodium polyacrylate was investigated as a precipitation inhibitor. The composition, morphology and IR spectra of calcium carbonate precipitate obtained in the absence and in the presence of sodium polyacrylate were studied. It was established that the effect of sodium polyacrylate on the mechanism of crystallization of carbonate sediment depends on the pH of the initial solution. The results of IR spectroscopy, X-ray diffraction analysis and images obtained by electron microscopy indicate the participation of polymer molecules in the formation of the crystalline structure of the carbonate precipitate.

Stabilization of Nanostructured Zeolite Particles: The Effect of Sodium Polyacrylate on the Disaggregation Kinetics and Threshold

The influence of sodium polyacrylate on the disaggregation kinetics and threshold of conglomerates of a natural agromineral, zeolite, under ultrasonic dispersion has been studied. It has been demonstrated that the use of sodium polyacrylate as a stabilizing additive has resulted in the reduction of the zeolite particle size, the increase in the content of isolated fractions, and significant decrease in the ultrasonic treatment duration. When the zeolite was dispersed with sodium polyacrylate, the particles achieved an average size of 750.0 nm after the first minute of cavitation treatment, while the dispersion of the agromineral without the additive required a 5-min treatment to achieve the same result. The use of sodium polyacrylate increased the stabilized state period of zeolite particles to half a year.

Effect of Sodium Poly Acrylate on Water Holding Capacity of Soak Pits

Effect of Sodium Poly Acrylate on Water Holding Capacity of Soak Pits

Effect of sodium polyacrylate on mechanical properties and microstructure of metakaolin-based geopolymer with different SiO2/Al2O3 ratio

The mechanical properties and microstructure of geopolymer are affected by the molar ratio of SiO2/Al2O3. Meanwhile, organic polymer has the effect of improving the toughness of geopolymer, which depends on the SiO2/Al2O3 ratio of geopolymer inevitably. Therefore, it is important to investigate the effect of the organic polymer on the mechanical properties and microstructure of geopolymer with varying SiO2/Al2O3 ratio for using organic polymer to modify geopolymer. In this work, the SiO2/Al2O3 ratios of metakaolin-based geopolymers are adjusted to 2.0, 2.5, 3.0, 3.5 and 4.0 by adding silica fume and β-Al2O3, with Na2O/SiO2, H2O/SiO2 being maintained at 0.2, 4.0, respectively. The geopolymers with each SiO2/Al2O3 ratios are modified by addition of 0, 0.4, 0.8, 1.2 and 1.6 wt% of sodium polyacrylate (PAAS).The mechanical properties of these samples are measured and the rate of change is used to characterize the effect of PAAS on the metakalin-based geopolymers. The mechanism is also shown by 29Si NMR, XPS and FTIR. The results show that the effects of polymer on the mechanical properties of metakaolin-based geopolymer are affected by SiO2/Al2O3 ratio and the effect becomes less obvious with SiO2/Al2O3 ratio increasing from 2.0 to 4.0. Incorporation of PAAS can reduce the degree of polymerization of [SiO]4 or [AlO]4 in geopolymer and form the Si‒O‒C bond, which are two main reasons for polymer improving the toughness of geopolymer. But these effects decrease when the SiO2/Al2O3 ratio of geopolymer increases from 2.0 to 4.0, which is corresponding to the effect on the mechanical properties. The toughening effect of organic polymer on geopolymer depends on the SiO2/Al2O3 ratio of geopolymer, and only the geopolymer with lower SiO2/Al2O3 ratio (no more than 2.5 in this work) can be significantly toughening modified by organic polymer. Therefore, it is necessary to consider the SiO2/Al2O3 ratio of the geopolymer when geopolymer modified by organic polymer is designed.

Effect of Polyelectrolyte and Fatty Acid Soap on the Formation of CaCO3 in the Bulk and the Deposit on Hard Surfaces.

The effects of sodium polyacrylate (NaPAA) as well as potassium oleate on the nucleation and calcium carbonate crystal growth on hard surfaces, i.e., stainless steel and silica, have been investigated at different temperatures. The relation between the surface deposition and the corresponding bulk processes has been revealed by combining dynamic light scattering (DLS), scanning electron microscopy (SEM), X-ray diffraction (XRD), and ellipsometry. The aim was to further our understanding of the crystal deposition/growth mechanism and how it can be controlled by the presence of polyelectrolytes (NaPAA) or soap (potassium oleate). The addition of polyelectrolytes (NaPAA) or soap (potassium oleate) decreases the size of CaCO3 particles in bulk solution and affects both crystal structure and morphology in the bulk as well as on hard surfaces. The amount of particles on hard surfaces decreases significantly in the presence of both potassium oleate and NaPAA. This was found to be a consequence of potassium oleate or NaPAA adsorption on the hard surface as well as on the CaCO3 crystal surfaces. Here, the polymer NaPAA exhibited a stronger inhibition effect on the formation and growth of CaCO3 particles than potassium oleate.

Effects of binders on electrochemical performance of nitrogen-doped carbon nanotube anode in sodium-ion battery

N-doped hollow carbon nanotubes (N-CNTs) with turbostratic structure are prepared as anode materials for sodium-ion battery. The effects of sodium polyacrylate (Na-PAA) and poly(vinylidene difluoride) (PVDF) binders on electrochemical performance are comparatively investigated. The obtained N-CNTs have disordered carbon structure and contain N-, O-functional groups, which electrochemical performance strongly depends on the binder used. The N-CNTs electrode with Na-PAA binder exhibits large capacity, high initial coulombic efficiency, excellent cycling stability and rate performance. Compared with the traditional PVDF binder, the water soluble Na-PAA binder shows electrochemical activity, lower internal resistance, and homogeneously formed solid electrolyte interface. Further investigations show that the binding capability of Na-PAA is closely related to the molecular weight. The Na-PAA with moderate molecular weight is more suitable as the binder of sodium-ion batteries with N-CNTs anode.

Study on the Effect of Sodium Polyacrylate and its Compounds on Artificial Warm Fog Dissipation

Sodium polyacrylate as a kind of high absorbent resin, has an excellent water absorption performance, is low in price and isn’t corrosive. Compounds of different particle sizes and components were prepared using sodium polyacrylate and sodium chloride. They were used in the fog chamber to disperse warm fog respectively then. Experiments were carried out to investigate how particle size and composition affect the warm fog dissipation. Results as follows are obtained: the time light transmittance recovers to 60% (t60%) is 85min when the fog dissipates naturally; 30g sodium polyacrylate whose average size is 30μm has a good effect on warm fog dissipation, t60% being 14min; when the sodium polyacrylate and sodium chloride are mixed by 1:2 in mass ratio, the fog elimination effect is the best, with t60% 6min. The reasons are analyzed at the same time.

Preparation of stable aqueous suspensions of antimony-doped tin oxide nanoparticles used for transparent and thermal insulation fluorocarbon coating

In order to prepare the highly stable aqueous suspensions of antimony-doped tin oxide (ATO) used for the transparent and thermal insulation fluorocarbon coating, the effect of sodium polyacrylate (PAAS) and polyvinyl alcohol (PVA) on the stability of the suspensions was investigated. The stability and dispersity of the suspensions were characterized using zeta potential analyzer, ultraviolet–visible spectrophotometer, and scanning electron microscope. No sediments were observed after 6-month storage of the ATO suspensions containing 0.1 wt% PAAS and 2.0 wt% PVA. The reason why aqueous suspensions were capable of stabilization was explained from a theoretical perspective. A new model of steric hindrance for colloid particles stabilized by binary dispersant was proposed, which may have positive contribution to other colloid system containing two dispersants. A nano-composite fluorocarbon coating, exhibiting a good thermal insulation and high transmittance, was formed after ATO suspensions were added in fluorocarbon emulsion. The temperature inside the chamber was decreased by 6.0 °C, and 75.0 % visible light rays could pass through the coating.

Effects of sodium polyacrylate on water retention and infiltration capacity of a sandy soil

Based on the laboratory study, the effects of sodium polyacrylate (SP) was investigated at 5 rates of 0, 0.08, 0.2, 0.5, and 1%, on water retention, saturated hydraulic conductivity(Ks), infiltration characteristic and water distribution profiles of a sandy soil. The results showed that water retention and available water capacity effectively increased with increasing SP rate. The Ks and the rate of wetting front advance and infiltration under certain pond infiltration was significantly reduced by increasing SP rate, which effectively reduced water in a sandy soil leaking to a deeper layer under the plough layer. The effect of SP on water distribution was obviously to the up layer and very little to the following deeper layers. Considering both the effects on water retention and infiltration capacity, it is suggested that SP be used to the sandy soil at concentrations ranging from 0.2 to 0.5%.

Mechanism of TiO2 stabilization by low molecular weight NaPAA in reference to water-borne paint suspensions

The effect of sodium polyacrylate (NaPAA), generally used as a dispersant in paint formulations, on the stability of zirconia- and alumina-coated TiO2 suspensions was investigated. The effect of percent solids and medium pH on NaPAA adsorption along with electrokinetics, rheology and stability in TiO2/NaPAA systems was systematically studied to understand the suspension properties of TiO2 under various conditions. Adsorption on the TiO2/NaPAA system exhibits a plateau, which decreases with increasing percent solids and medium pH and follows the Langmuir equation. The presence of a stable region above the plateau concentration is in good agreement with viscosity and zeta potential measurements. Zeta potential values of TiO2 are high enough to provide an appropriate dispersion in the plateau region. It is shown that stabilization of TiO2 suspensions with appropriate adsorption of NaPAA is achieved through electrosteric stabilization. The medium pH on stability of the system is particularly critical. Maximum stabilization is obtained at pH values where the presence of anionic carboxylate groups of NaPAA is available in loops–tail conformation.

Effects of Sodium Polyacrylate and Phytase-Supplemented Diet on Performance and Phosphorus Retention in Chicks

Two experiments were conducted to evaluate the effects of addition of sodium polyacrylate (SPA) to a phytase-supplemented diet on the performance and phosphorus (P) retention of chicks. In experiment 1, chicks were randomly allocated to four dietary treatments which were fed from 7 to 21 days of age: i) basal diet (low nonphytate phosphorus (0.23% NPP)); ii) basal with 250 U/kg diet of phytase; iii) as (ii) with 2.5 g/kg diet of SPA; and iv) as (ii) with 5.0 g/kg diet of SPA. In experiment 2, three replicates, each with three chicks, were fed from 7 to 28 days of age the basal diet (0.23% NPP) with supplementation of phytase (0, 300, 600, 900 U/kg diet) and SPA (0, 2.5 g/kg diet) in a 4x2 factorial arrangement. In Experiment 1, feed efficiency was improved and excreted P was 10% less with phytase supplementation. However, the addition of SPA did not affect performance or P excretion. Dietary SPA supplementation to the diets showed significantly higher amounts of P retention, and highest values were observed in chicks fed 2.5 g/kg of the SPA-supplemented diet. In Experiment 2, feed efficiency was improved with phytase supplementation, and the addition of SPA showed significant improvement in feed efficiency. Excreted P was significantly lower in chicks fed SPA-supplemented diets, and the retained P coefficient improved with SPA supplementation. In conclusion, the increased transit time of digesta with suitable supplementation levels of SPA may allow phytase activity to be more effective in the degradation of phytate, and improve P retention.

α-Tricalcium phosphate hydrolysis to octacalcium phosphate: effect of sodium polyacrylate

α-Tricalcium phosphate (α-TCP) hydrolysis into octacalcium phosphate (OCP) has been investigated in phosphoric acid solution at different concentrations of sodium polyacrylate (NaPA). The hydrolysis process has been followed by powder X-ray diffraction, infrared absorption and scanning electron microscopy analyses. In the absence of the polyelectrolyte, α-TCP undergoes a complete transformation into OCP in 24h. The presence of polyacrylate in solution inhibits the hydrolysis so that a NaPA concentration of 0.5μm is sufficient to lengthen the time required to complete the hydrolysis to 4 days. The variation of Ca2+ concentration in the soaking solution suggests that the transformation occurs through α-TCP dissolution followed by OCP precipitation. The delayed OCP nucleation and growth in the presence of polyacrylate implies a preferential adsorption of the polyelectrolyte on the growing OCP crystals, which induces an anisotropic reduction of the coherence lengths of the perfect crystalline domains.

Effect of sodium polyacrylate on the hydrolysis of octacalcium phosphate

Octacalcium phosphate (OCP) hydrolysis into hydroxyapatite (HA) has been investigated in aqueous solutions at different concentrations of sodium polyacrylate (NaPA). In the absence of the polyelectrolyte, OCP undergoes a complete transformation into HA in 48 h . The hydrolysis is inhibited by the polymer, which is significantly adsorbed on the crystals, up to about 22 wt.%. A polymer concentration of 10 −2 mM is sufficient to cause a partial inhibition of OCP to HA transformation, which is completely hindered at higher concentrations. The small platelet-like crystals in the TEM images of partially converted OCP can display electron diffraction patterns characteristic either of OCP single crystals or of polycrystalline HA, whereas the much bigger plate-like crystals exhibit diffraction patterns characteristic of OCP single crystals. The polyelectrolyte adsorption on OCP crystals is accompanied by an increase of their mean length and by a significant reduction of the coherence length of the perfect crystalline domains along the c-axis direction. It is suggested that the carboxylate-rich polyelectrolyte is adsorbed on the hydrated layer of the OCP (100) face, thus inhibiting its in situ hydrolysis into HA.

Synthesis and hydrolysis of octacalcium phosphate: effect of sodium polyacrylate

A structural and morphological investigation has been carried out on octacalcium phosphate (OCP) synthesized in aqueous solution in the presence of different concentrations of sodium polyacrylate (NaPA) (from 0.375 to 5 μM). The presence of the polyelectrolyte inhibits the crystallization of OCP and reduces significantly the coherence length of the perfect crystalline domains. The inhibition of the crystal growth along the directions corresponding to the crystallographic axes is almost isotropic and indicates no preferential regular interaction of polyacrylate with the structure of OCP. In agreement, the lattice constants of OCP do not change as a function of the concentration of the polyelectrolyte, which is not significantly adsorbed on the crystals. Scanning electron microscopy (SEM) images of OCP display the presence of spherules and double spheres. The elongated blades which constitute the spherules and the walls of the hollow spheres become shorter with increase in NaPA concentration. OCP has been submitted to hydrolysis at pH 7.4 and 60°C. The hydrolysis is inhibited by NaPA, which prevents the transformation into hydroxyapatite. The results of IR absorption and thermogravimetric analyses (TG-DTG) indicate that the polyelectrolyte is significantly adsorbed on the products of hydrolysis. Adsorption increases on increasing NaPA concentration in solution up to about 22 wt.%, and it probably takes place through interaction between carboxylate ions and the hydrated layers of the (100) face of the OCP structure.

Effect of sodium polyacrylate on the properties of dilute and concentrated BaSO4 dispersions

The adsorption of sodium polyacrylate on BaSO4 particles has been studied and the adsorption characteristics have been related to the properties of both dilute and concentrated dispersions. The extent of particle aggregation has been monitored by turbidity or viscosity measurements for dilute and concentrated dispersions, respectively. For dilute dispersions, the results show that in the absence of electrolyte, aggregation is prevented when the extent of adsorption is much less than plateau coverage. The e.s.r. technique reveals that the polyanions are adsorbed in ‘trains’ under these conditions and, since the zeta potential is sufficiently high, charge stabilisation predominates. For concentrated dispersions the same mechanism is effective once a critical polymer concentration has been reached, this concentration being greater than that for dilute dispersions but still less than plateau coverage. This is possibly due to the requirement of a more uniform charge distribution. In the presence of electrolyte the amount of polymer necessary to bring about stabilisation corresponds closely to the amount of polymer adsorbed at the end of the high-affinity region of the adsorption isotherm for both dilute and concentrated dispersions. Under these conditions the adsorbed polymer adopts a more extended configuration with loops and tails protruding out into solution, thus enabling steric repulsive forces to come into operation.

Effects of sodium polyacrylate (PANa) on acute esophagitis by gastric juice in rats.

Sodium polyacrylate (PANa) is a water-soluble, high-molecular compound, and its aqueous solution shows a very high viscosity and stringiness. In the present study, preventive effects of PANa on three kinds of esophageal lesions induced by gastric juice were examined in comparison with those of aceglutamide aluminum and sodium alginate. The influences of PANa on gastric contents were also studied. The preventive effect of PANa given intraesophageally on esophageal lesions induced by the intraesophageal application of gastric juice was more potent than aceglutamide aluminum and sodium alginate. Oral administration of PANa inhibited the formation of esophageal ulcer by pylorus ligation more markedly than aceglutamide aluminum, whereas sodium alginate had no effect in a high dose of 500 mg/kg. In preventing gastric ulcer which occurred simultaneously with the esophageal ulcer after the pylorus ligation, aceglutamide aluminum was most potent, and PANa was as potent as sodium alginate. Oral administration of PANa showed a more protective effect than aceglutamide aluminum on the esophageal ulceration induced by the simultaneous ligations of the pylorus and limiting ridge, whereas sodium alginate in a high dose of 500 mg/kg had little effect on the ulcer formation. PANa caused only a slight increase in the pH of gastric juice and a slight decrease in pepsin activity. From the results, it may be concluded that PANa showed an antiulcerogenic activity mainly due to its mucosa covering action against gastric juice.