Sodium polyacrylate, PAAS

Sodium polyacrylate is a white crystal particles or liquid. Odorless and tasteless. Very hygroscopic. Polymer compounds with hydrophilic and hydrophobic groups. Slowly dissolves in water to form an extremely viscous transparent liquid, its viscosity is about 15-20 times that of CMC and sodium alginate.

Classification by water solubility:
A.   Water-swellable sodium polyacrylate is a kind of highly absorbent resin that we often talk about. It can absorb hundreds to thousands of times its own weight of water. It is non-toxic, harmless and pollution-free. It has strong water absorption capacity and high water retention capacity. The high molecular weight polymer obtained by acrylic acid polymerization → high water retention capacity, balance of absorption under high load, the absorbed water cannot be squeezed out by simple physical methods, and can release and absorb water repeatedly. Applied in agriculture and forestry, it can form a "micro reservoir" at the roots of plants. In addition to absorbing water, highly absorbent resins can also absorb fertilizers and pesticides, and slowly release them to increase fertilizer and drug efficacy.

B.  Water-soluble sodium polyacrylate products are very common in the market, generally mainly solid micro powder type. Water needs to be added for dissolution when used, and the preparation concentration can be adjusted according to demand. Water-soluble sodium polyacrylate has various functions due to its different molecular weight and is widely used in food and other industries. Edible sodium polyacrylate belongs to this category. Edible sodium polyacrylate is a high molecular compound with hydrophilic groups, which slowly dissolves in water to form an extremely viscous transparent solution.


Food grade sodium polyacrylate:
1. Used as a thickening agent in food, it has the following effects:
(1) Enhance the protein cohesion in raw flour.
(2) Combine starch particles with each other and disperse and penetrate into the protein network structure.
(3) Form a dense dough with a smooth and shiny surface.
(4) Form a stable dough colloid to prevent soluble starch from exuding.
(5) It has strong water retention, allowing moisture to be evenly maintained in the dough and prevent drying.
(6) Improve the extensibility of dough.
(7) Stably disperse the fat content in the raw materials into the dough.

2. As an electrolyte, it interacts with proteins, changes the protein structure, enhances the viscoelasticity of food, and improves tissue.

3. Application examples:
(1) Bread, cakes, noodles, macaroni, improve raw material utilization, improve taste and flavor. Dosage 0.05%.
(2) Aquatic products, canned food, dried seaweed, etc., strengthen the structure, maintain freshness, and enhance the taste.
(3) Sauces, tomato sauce, mayonnaise, jam, cream, soy sauce, thickeners and stabilizers.
(4) Juice, alcohol, etc., dispersants.
(5) Ice cream and caramel sugar improve taste and stability.
(6) Frozen food, processed aquatic products, surface gelling agent (preservation).

Industrial grade sodium polyacrylate:
Sodium polyacrylate is a commonly used dispersant. It is a colorless or light yellow viscous liquid at room temperature. It is non-toxic and weakly alkaline. It is insoluble in organic solvents such as ethanol and acetone, and is easily soluble in water and sodium hydroxide aqueous solution. In aqueous solutions such as calcium hydroxide and magnesium hydroxide, as the number of alkaline earth metal ions increases, they first dissolve and then precipitate. It can operate under alkaline and medium concentration multiple conditions without scaling. The molecular weight is about 500-3000. It can disperse microcrystals or sediment of calcium carbonate, calcium sulfate and other salts in the water without settling, thereby achieving the purpose of scale inhibition.

In addition to being used as a scale inhibitor and dispersant in circulating cooling water systems such as power plants, chemical plants, fertilizer plants, refineries and air conditioning systems. It is also widely used in papermaking, textile printing and dyeing, ceramics, coatings, building materials and other industries. When used as a papermaking coating dispersant, when the relative molecular weight is 2000-4000 and the coating concentration is 65% to 70%, it can still have good rheology and aging stability. Those with molecular weights between 1000-3000 are used as water quality stabilizers and scale control agents during black liquor concentration. Those with a molecular weight above 100,000 are used as coating thickeners and water-retaining agents to increase the viscosity of synthetic latexes such as carboxylated styrene-butadiene latex and acrylate emulsions to prevent water from escaping and maintain the stability of the coating system. Those with a molecular weight above 1,000,000 are used as flocculants. It can also be used as super absorbent resin and soil conditioner.