Thioglycolic acid is used as reagent for the preparation of different chemicals such as pesticides, herbicide, or for some polythiols and thio-esters.Thioglycolic Acid and it salts and esters modify hair fibers to facilitate changes to the structure of the fibers, such as with permanent waves or with hair straightening. They are also used to chemically break down hair fibers so that unwanted hair can be removed by simply wiping it from the skin.
TGA is used as a chemical depilatory and is still used as such, especially in salt forms, including calcium thioglycolate and sodium thioglycolate. TGA is the precursor to ammonium thioglycolate that is used for permanents.
Thioglycolic acid and its derivatives as well as various other mercaptocarboxylic acids have become widespread. Both the mercapto and carboxylic functions in thioglycolic acid are chemically active, as is the methylene group in esters under alkaline conditions. The most important reactions involve the thio disulfide interchange reactions with cystine units in hair protein, keratin, which property is applied in cosmetology for hair waving, and the formation of esters to give tin stabilizers for poly(vinyl chloride). For esters, the ability to build N and S heterocycles promises prospective development in fine chemistry. Other mercaptocarboxylic acids have experienced interesting developments, mainly as polymer modifiers and polymer stabilizers.
