Poly or PAA or Carbomer is a type of anionic polymer

Polymer

A polymer is a large molecule composed of repeating structural units. These subunits are typically connected by covalent chemical bonds...

. The monomer of poly(acrylic acid) is acrylic acid

Acrylic acid

Acrylic acid is an organic compound with the formula CH2=CHCO2H. It is the simplest unsaturated carboxylic acid, consisting of a vinyl group connected directly to a carboxylic acid terminus. This colorless liquid has a characteristic acrid or tart smell. It is miscible with water, alcohols,...

. In a water solution at neutral pH

PH

In chemistry, pH is a measure of the acidity or basicity of an aqueous solution. Pure water is said to be neutral, with a pH close to 7.0 at . Solutions with a pH less than 7 are said to be acidic and solutions with a pH greater than 7 are basic or alkaline...

, many of the side chains of PAA will lose their protons and acquire a negative charge. This makes PAA a polyelectrolyte

Polyelectrolyte

Polyelectrolytes are polymers whose repeating units bear an electrolyte group. These groups will dissociate in aqueous solutions , making the polymers charged. Polyelectrolyte properties are thus similar to both electrolytes and polymers , and are sometimes called polysalts. Like salts, their...

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Dry PAA is a white solid. It is capable of adsorbing many times its weight in water, and hence is used in disposable diapers.

It also is used as a thickening agent

Thickening agent

Thickening agents, or thickeners, is the term applied to substances which increase the viscosity of a solution or liquid/solid mixture without substantially modifying its other properties; although most frequently applied to foods where the target property is taste, the term also is applicable to...

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It inactivates the antiseptic

Antiseptic

Antiseptics are antimicrobial substances that are applied to living tissue/skin to reduce the possibility of infection, sepsis, or putrefaction...

 chlorhexidine gluconate

Chlorhexidine gluconate

Chlorhexidine is a chemical antiseptic. It is effective on both Gram-positive and Gram-negative bacteria, although it is less effective with some Gram-negative bacteria. It has both bactericidal and bacteriostatic mechanisms of action, the mechanism of action being membrane disruption, not ATPase...

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