The preparation of poly (ethylene terephthalate) using trivalent antimony compounds as catalysts
Abstract
Abstract A process for preparing polyethylene terephthalate wherein dimethyl terephthalate is reacted with ethylene glycol to form an ester of ethylene glycol and terephthalic acid or where terephthalic acid is reacted with ethylene glycol to form an ester of terephthalic acid and ethylene glycol where the resulting ester is polycondensed in the presence of a polycondensation catalyst, the improvement comprising carrying out the condensation or polymerization of the ester in the presence of a catalytic amount of a trivalent antimony compound exhibiting two direct carbon to antimony bonds and one direct bond from an antimony atom to oxygen; to oxygen linking an organic radical to said antimony atom; to oxygen linking another antimony atom to said antimony atom; or to a halogen atom.
Inventors
- 👤 John J Ventura
- 👤 James Mackey
Bibliographic Details
Claims Analysis
Total Claims: 15References Cited (Backward Citations)
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