Polyacrylic acid

Polyacrylic acid (CAS 9003-01-4), commonly known as PAA and sold under the Carbomer trade name in cosmetic grades, is a synthetic polymer used across industrial and personal care markets.

Where is Polyacrylic acid used?

• Water treatment: scale inhibitor controlling calcium carbonate and calcium sulfate deposits in cooling towers, boilers, and reverse osmosis systems
• Personal care: Carbomer grades build viscosity and stabilize emulsions in gels, creams, and lotions
• Textile and paper processing: dispersant for pigments and retention aid
• Agricultural formulations: water retention in soil conditioners and carrier in slow-release fertilizer systems
• Ion exchange resins.
• It functions as a rheology modifier, scale inhibitor, and flocculant depending on the application.

Good to know: Carbomer grades, such as Carbomer 940 and 980, are available to USP and Ph. Eur. standards for cosmetic and pharmaceutical use.

Formulation notes

• When used alone, a dosage of 1-15 mg/L is preferred.
• Inhibits calcium phosphate and zinc scale by >98% at 10-15 ppm.
• The dosage must be set according to the water quality and the equipment materials.
• In aqueous solutions it can form polycomplexes with oppositely charged polymers such as chitosan and with surfactants.
• Normally supplied as a powder in acidic form; ionizes when a pH-raising (alkaline) agent is added, expanding the network and giving higher-viscosity products.
• When added to water, the powder form generally must be well dispersed and is usually activated before mixing with water, then begins to swell with sufficient mixing.

Typical specification

• Active solid content of 48.0% to 50.0% minimum.
• Carbomer codes 910, 934, 940, 941 and 934P indicate the molecular weight and specific components of the polymer.
• Molecular weight range of 2,000 to 5,000 g/mol.
• Linear polyacrylic acid is a water-soluble polymer; the crosslinked neutralized form is water-swellable (superabsorbent) rather than soluble.

Regulatory status

• The HS code of polyacrylic acid is 3906.90.

Storage, packaging and handling

• Containers should be kept tightly sealed when not in use.

Frequently asked questions about Polyacrylic acid

In what forms is polyacrylic acid used in many applications?

For many applications, polyacrylic acids are used in the form of alkali metal or ammonium salts, e.g., sodium polyacrylate.

What are the incompatibilities of polyacrylic acid with other substances?

Polyacrylic acid can inactivate the antiseptic chlorhexidine gluconate.

What are the primary industrial applications of polyacrylic acid?

In detergents and cleaning agents, polyacrylic acid enhances anti-redeposition and water-softening properties; in coatings and adhesives, it improves film formation and durability; and it is used in antifoulant formulations for heat exchangers and refinery furnaces.

Technical content is compiled and updated by the SoleChem product team from public technical sources; the certificate of analysis (COA) governs product-specific specifications.