Terephthalic acid is a pure white powder obtained by oxidation of paraxylene in the presence of catalysts and acetic acid.
Does not form monomeric anhydride; when heated with acetic anhydride converts to polymeric anhydride.
The interaction of terephthalic acid with alcohols leads to the formation of esters, of which dimethyl terephthalate is of the most practical importance.
Synonyms and international names
RUS: Terephthalic acid (TPA), p-benzenedicarboxylic acid, 1, 4-benzenedicarboxylic acid, p-phthalic acid,
OTPA purified terephthalic acid
ENG: Purified terephthalic acid (PTA), p-benzenedicarboxylic acid, 1, 4-benzenedicarboxylic acid, p-phthalic acid,
PTA purified terephthalic acid, TPA
Application
The main area of application is the production of polyethylene terephthalate (PET),
much smaller volumes are used in the production of dimethyl terephthalate and polybutylene terephthalate (PBTF).
A transparent heat-resistant polymer, polyethylene terephthalate, is synthesized from terephthalic acid.
It is obtained by polycondensation of ethylene glycol with terephthalic acid.
Bottles are made of it, polyester fiber terylene (another, more common name - lavsan is an abbreviation for "Laboratory of High Molecular Compounds of the Academy of Sciences"), packaging materials, including those for the food industry, radio components, and chemical equipment.
To obtain PET for food purposes, the content of impurities in TPA is of great importance - products of incomplete oxidation of paraxylene, that is, terephthalic acid of grade A is required, with a minimum content of impurities.
Based on this, the volume of production of terephthalic acid is mainly determined by the demand from the manufacturers of polyester products. Esters of terephthalic acid - diethyl terephthalate and dimethyl terephthalate - are of great importance.
Terephthalic acid dimethyl ester is one of the most important chemical products used for the production of polyester fibers, polyoxadiazoles, polybenzimidazoles, alkyd resins and plasticizers.
Packaging
Big bags 1.1 tons, bags-tabs