Sodium polyacrylate

Sodium polyacrylate (SO-dee-um pol-ee-AK-ruh-late) is an odorless, grainy white powder. Its most impressive property is its ability to absorb large amounts of fluid, up to 800 times its volume of distilled water and lesser amounts of other liquid mixtures. This property accounts for one of its primary applications, in the manufacture of disposable diapers. Diapers made from sodium polyacrylate are able to absorb up to 30 grams of urine for each gram of diaper. 

Sodium polyacrylate is produced by the reaction between acrylic acid (H2C=CHC00H) and its sodium salt (H2C=CHC00Na). The product of this reaction is a long-chain copolymer consisting of alternate units of acrylic acid and sodium acrylate. A copolymer is a polymer made of two different monomers, in this case, acrylic acid and sodium acrylate. What makes this polymer different from most other 

Sodium polyacrylate. Red atoms are oxygen white atoms are hydrogen black atoms are carbon turquoise atom is sodium. Gray sticks indicate double bonds, publishers 

When water is added to the polymer, it forces carboxyl groups away from each other, forcing the mesh to open up 

Sodium polyacrylate is also used as a thickening agent in medical gels used to treat bed sores, which are open wounds that develop when a person is bed ridden for too long. The compound is also added to detergents and to potting soils to help retain water. The compound is now being used in some parts of the world where there is insufficient rain to allow 

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Other. A large variety of additives are used in paper-coatiag colors primarily to modify the physical properties of the colors (102). At high soHds concentrations in water, mineral pigment particles tend to associate and form viscous pastes. Dispersants (qv) are used to prevent this and to provide low viscosity slurries. Common dispersants include polyphosphates and sodium polyacrylate [9003-04-7]. Various water-soluble polymers are added to coatiag colors and act as water-retention agents and as rheology modifiers. 

Acrylate and acrylamide polymers have several uses in drilling fluids, one of which is for filtration control. Sodium polyacrylates [9003-04-7] having molecular weights near 250,000 are exceUent temperature-stable filtration control agents for both fresh- and salt water muds, provided the concentration of water-soluble calcium is <400 mg/L (83). The calcium ions are precipitated using a carbonate such as soda ash, before adding the polyacrylate at concentrations up to ca 6 kg/m (3 Ib/bbl). 

Sodium polyacrylate (NaPAA) [9003-04-7]. Commercial polyacrylamide was neutralised with an aqueous solution of NaOH and the polymer ppted with acetone. The ppte was redissolved in a small amount of water and freeze-dried. The polymer was repeatedly washed with EtOH and water to remove traces of low... 

Ionic repulsion between anionic samples and the resin causes poor resolution. As shown in Fig. 4.17, the addition of only 0.01 M NaNO, results in normal elution and peak shape for an anionic polymer, sodium polyacrylate. 

Anionic hydrophilic Sodium chondroitinsulfate, sodium alginate, carboxymethyj cellulose, sodium polyacrylate, sodium hyaluronate Buffer or salt solution (e.g., 0.1 M NaNO,)... 

Anionic, hydrophilic Sodium polyacrylate, sodium hyaluronate, carboxymethyl cellulose 0.1-0.3 M salt/buffer, pH 7-9... 

Acrylic acid and sodium polyacrylates. Products based on acrylic acid or sodium polyacrylates are commonly used and generally perform satisfactorily on source waters with a TDS below 2,000 to... 

Sodium hydroxide, commercial solution Sodium polyacrylate (45%)... 

Efficiencies Related to Composite Films Electrogenerated from 1 M Pyrrole plus 10 2 M Sodium Polyacrylate Aqueous Solution by Polarization of a 1-cm2 Platinum Electrode at 800 mV for Different Polymerization Times... 

Ferry, G. V. Gill, S. (1962). Transference studies of sodium polyacrylate under steady state electrolysis. Journal of Physical Chemistry, 66, 999-1003. 

In this investigation, you will examine three different polymers. First, you will examine the addition polymer sodium polyacrylate. This polymer contains sodium ions trapped inside the three-dimensional structure of the polymer. When placed in distilled water, the concentration of sodium ions inside the polymer is much greater than the concentration of sodium ions outside the polymer. The concentration imbalance causes water molecules to move hy diffusion into the polymer. As a result, the polymer absorbs many times its own mass in distilled water. 

How much water can sodium polyacrylate absorb What properties do polymers have in common How do polymers differ ... 

Sodium polyacrylate is irritating to eyes and nasal membranes. Use only a small amount, and avoid inhaling the powder. 

Examine the sodium polyacrylate powder. Record your observations. 

Calculate the mass of water that was absorbed by the sodium polyacrylate polymer. (Note 1 mL of water = 1 g)... 

Use the mass of the sodium polyacrylate polymer and the mass of the water it absorbed to calculate the mass/mass ratio of the polymer to water. 

What practical applications might the sodium polyacrylate polymer be used for ... 

What happened when you added the salt Come up with an explanation for what you observed. Search for a discussion of sodium polyacrylate on the Internet to check your explanation. 

Sodium polyacrylate absorbs less tap water than distilled water. Design and carry out an investigation to compare the mass of tap water absorbed to the mass of distilled water absorbed by the same mass of powder. 

The normal dispersants used for both kaolin and calcium carbonate pigments are aqueous solutions of sodium polyacrylate. These are prepared by free radical polymerisation using various combinations of initiators and terminators which may be proprietary to the manufacturer. Number average molecular weights are... 

Colloid Chemistry of Sodium Polyacrylate Dispersed Calcium Carbonate Slurries... 

A series of slurries of high solids, dispersed ground calcium carbonate were prepared. Firstly, a sample of Carrara marble was ground without dispersant to a mean size of 0.5 fim. This was then filtered to a solids level of 76% (volume fraction 46%), before being thoroughly mixed with the required dose of sodium polyacrylate dispersant and adjusted to a constant solids level of 70%. Doses ranged from zero to 25mgg (2.5%) of calcium carbonate. Samples were then left for two days to reach a steady-state adsorption level. After this they were sheared and their viscosity (Brookfield RV, 100 rpm, spindle 3) was measured. 

Even at a dose level of 5 mgg some 80% of the contribution to ionic strength comes from unadsorbed sodium polyacrylate. 

Fundamental studies of the effects of sodium polyacrylate have shown it to be an electrosteric dispersant, for which the steric component of interparticle repulsion is the dominant one at the typical dose rates used commercially. In such dispersions the main contributor to solution ionic strength is unadsorbed polyacrylate. As well as representing a waste of valuable dispersant polymer, this unadsorbed material also reduces the effectiveness of the adsorbed material as a steric dispersant by compressing the conformation of the adsorbed layer. 

Fig. 17 Ratio of third to first vibrational peak of pyrene emission spectrum as a function of DTAB concentration in the presence of 1 g/L sodium polyacrylate...

Fig. 18 Critical aggregate concentration, CAC of DTAB in 1 g/L sodium polyacrylate in 0 and 0.03 M added NaCl...

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