Methoxy PEG-7 is a chemical compound, polyethylene glycol (PEG (Polyethylene glycol)) ether of methoxyethanol attached to a variable length PEG (Polyethylene glycol) chain (7 ethylene glycol units).

The name defines the structure of the molecule

• "Methoxy" indicates the presence of a methoxy group (-OCH3). It's an ether group derived from oxygen bonded to a methyl group.
• "PEG" stands for "Polyethylene Glycol", which is a polymer of the monomer ethylene oxide. It's often used in cosmetics and pharmaceuticals for its solubilizing properties and as a conditioning agent.
• "7" indicates the average molecular weight or the number of repeating units of ethylene oxide in the polymer. In this case, there are 7 repeating units of ethylene oxide.

So, "Methoxy PEG-7" essentially means a Polyethylene Glycol with an average of 7 repeating units of ethylene oxide and modified with a methoxy group.

Description of the raw materials:

• Polyethylene Glycols (PEG). Polyethylene glycols are obtained through the polymerization of ethylene oxide. They are used as the main raw material for the synthesis of Methoxy PEG-7.
• Methanol. Methanol is a raw material that provides the methoxy group (-OCH3) to the compound. It is used for the modification of polyethylene glycols, adding the methoxy group to the polymer chain.

Summary of the industrial chemical synthesis process:

• Preparation of polyethylene glycols. Ethylene oxide is polymerized to obtain polyethylene glycols with the desired chain length of ethylene oxide units.
• Modification with methanol. Polyethylene glycols are treated with methanol in the presence of specific catalysts to add the methoxy group (-OCH3) to the structure of the polyethylene glycols, forming Methoxy PEG-7.
• Purification of the product. Methoxy PEG-7 is purified to remove any impurities or unwanted residues.
• Characterization of the product. The product is characterized using chemical and physical analyses to confirm its identity and assess its quality.
• Packaging of Methoxy PEG-7 into appropriate containers for distribution and use.

It appears in the form of a white powder. 

What it is used for and where

Cosmetics

• Solvent. It is a substance for dissolving or dispersing surfactants, oils, dyes, flavourings, bactericidal preservatives in solution.

Since the PEG (Polyethylene glycol) family is very numerous and can be found in cosmetic, industrial, pharmaceutical, medical and other products, we need to make an introductory statement on the subject, which is rather complex from a safety point of view because these products not only come into contact with the skin, but, as in the case of medical products, are ingested.

PEGs (polyethylene glycol) polymerise condensed ethylene oxide and water and are referred to as polyethylene glycols, but are actually complex chemical components, polymers bonded together. For example, plastic is polyethylene and has a hard consistency, while polyethylene combined with glycol forms a liquid. PEGylation is produced not only as etherification, but also as transesterification, which is the transformation of an alcohol by an ester. 

The number appearing after the abbreviation PEG represents the molecular weight and the higher this number is, the less it penetrates the skin.

Safety. 

The term 'eth' refers to the ethoxylation reaction with ethylene oxide after which residues of ethylene oxide and 1,4-dioxane, chemical compounds considered carcinogenic, may remain. The degree of safety therefore depends on the degree of purity of the compound obtained. At present, no manufacturer is known to provide this information on the label.

CAS:   9004-74-4