Polyethylene glycol 2000, often abbreviated as PEG 2000, is a polymeric compound that belongs to the class of polyethylene glycols. Polyethylene glycols are polymers made up of repeating ethylene glycol units. The number "2000" in PEG 2000 refers to its approximate molecular weight, which is around 2,000 grams per mole. Molecular weight is a measure of the size and mass of a molecule.

PEG 2000 is a water-soluble, waxy solid or viscous liquid depending on temperature. It has a variety of uses in different industries and applications, including:

1. Pharmaceuticals: PEG 2000 is used in the pharmaceutical industry as a component in various drug formulations. It is often used as an excipient to improve the solubility of poorly water-soluble drugs or to modify the release rate of drugs in controlled-release formulations.

2. Cosmetics: PEG 2000 is used in cosmetic and personal care products as a thickening agent, emulsifier, and moisturizer. It helps stabilize and improve the texture of creams, lotions, and other beauty products.

3. Food: In the food industry, PEG 2000 may be used as a food additive, mainly as a thickener, stabilizer, or emulsifier in certain products. However, it is important to note that the use of PEGs in food is regulated, and specific grades of PEGs are approved for different applications.

4. Industrial Applications: PEG 2000 is used in various industrial processes as a lubricant, surfactant, and in the production of certain chemical compounds.

5. Laboratory and Research: PEG 2000 is sometimes used in laboratories for various applications, including as a precipitating agent in protein crystallization and as a component in molecular biology experiments.