Papers by Keyword: Sodium Polyacrylate

Abstract: Hydrogel spheres made of sodium polyacrylate with free absorption of water can increase in volume by 100-1000 times due to the violation of the balance of forces of attraction and repulsion between the links of the gel. The addition of water will shift the balance in favor of the repulsive forces. This property will allow them to be used in cement systems as an active expanding aggregate, which will compact the structure, reduce the water-cement ratio during the formation of the cement paste structure, and then give water to the hardening cement stone. The hydrogel sphere itself will decrease in volume to its initial state and will leave the pore in its place. The resulting material can be considered aerated concrete with compacted inter-pore partitions. The advantage of this method over the traditional method of self-compacting masses is that there is no need to supply thermal energy to activate the expansion of the active aggregate, for example, by passing an electric current through the hardening mass. In this article, the properties of the hydrogel are investigated, the dynamics of the expansion of hydrogel spheres in water at different temperatures is determined.

Abstract: 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% (t_60%) is 85min when the fog dissipates naturally; 30g sodium polyacrylate whose average size is 30μm has a good effect on warm fog dissipation, t_60% 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 t_60% 6min. The reasons are analyzed at the same time.

Abstract: This report mainly studied the influence of dosage of the sodium polyacrylate on mechanical properties of slag-based geopolymer, and secondary studied the effects on mechanical properties of polyacrylic acid. The analyzing results indicate that compare to the polyacrylic acid, sodium polyacrylate has obvious effects on mechanical properties of slag-based geopolymer. And it’s mainly reflects on the nature of the 28 d, it’s early effects is not obvious. The mechanical properties of slag-based geopolymer doesn’t change with the dosage of sodium polyacrylate increase linearly, but overall mechanics properties is significantly superior to the blank sample.

Abstract: A spherical humidity control composite material with excellent humidity control performances has been prepared by twice foaming method. The composite comprises a natural polymer derivative (KGM), a porous natural mineral (Halloysite) and an Sodium polyacrylate (PAAS). It has high capacity for moisture adsorption, fast response to humidity changes, and small range for equilibrium humidity control. The moisture adsorption content of the composite material is 1.10 (g/g) of its own weight. The moisture absorption rate is 0.3948 (g/7h•g^-1), and moisture desorption rate is 0.4682 (g/7h•g^-1). The composite material has an equilibrium humidity control ranging from 50%RH to 53%RH. It can reach to the equilibrium levels within 60 minutes. It is suitable for maintaining a proper micro-environment for places such as museums or galleries.

Abstract: The decomposition behavior of synthetic β-2CaO•SiO₂ by adding sodium polyacrylate (NaPAA), polyethylene glycol (PEG) and their mixture at 80°C in sodium aluminate solution was investigated. The SiO₂ concentration in the reacted sodium aluminate solution decreases as the polymer surfactant charge increases, but does not change obviously when each surfactant is added over 12.5 mg/L. The amount of CaCO₃, hydro-garnet and sodium aluminum silicate hydrate in the decomposed solid with polymer surfactant addition is much smaller than that without surfactant addition. The losses of Na2O and Al₂O₃ are greatly decreased due to polymer surfactant addition. The inhibition sequence of β-2CaO•SiO₂ decomposition by polymer surfactants in sodium aluminate solution is mixture of NaPAA and PEG, NaPAA, PEG.

Abstract: Dyes containing wastewater lead to severe environmental pollution. Polyacrylates both dissolved in water and bonded to polyester fabrics were used to remove dye molecules from simulated wastewater. The Fourier transform infrared spectra, scanning electron microscopy and UV spectrophotometry were applied to characterize the grafting and the adsorption behavior of polyacrylates. The adsorption behaviors were described by the Lagergren’s pseudo second kinetic equation with physical interaction mechanism. The adsorption rate and equilibrium value were almost independent of adsorption temperature. The chemical bonding substantially suppressed the polymer chain mobility and thus weakened the removal efficiency.

Abstract: Electrosteric stabilization of a commercially available boehmite powder in water was investigated to perform milling experiments and reduce the particle size to the nanoscale range. The effect of three sodium polyacrylate dispersants (Na-PA) with different molar masses (2,100, 8,000, 15,000 g/mol) on the suspension properties before and after milling experiments was assessed by electroacoustic measurements in comparison with rheological tests. A significant loss of the stabilizing effect of the sodium polyacrylates due to the application of mechanical energy was detectable. Measurements of the adsorbed amount of the dispersants after milling via detection of the COD in the background solution show a considerable desorption from the particle surface. Accessorily performed analyses of the molar mass of the polymers yielded a destruction of the polymer chains due to the mechanical energy.