Process for the preparation of polyesters
Abstract
Abstract PROCESS FOR THE PREPARATION OF A POLYESTER IN WHICH AT LEAST 80% OF THE RECURRING STRUCTURAL UNTIS ARE COMPOSED OF ETHYLENE TERPHTHALATE UNTIS, WHICH COMPRISES POLYCONDENSING BIS(B-HYDROXYETHYL) TEREPHTHALATE, OR A MIXTURE OF BIS (B-HYDROXETHYL)TEREPHTHALATE OF THE QUANITY SUFFICIENT TO GIVE AT LEAST 80% OF ETHYLENE TEREPHTHALATE UNITS TO THE PRODUCT POLYESTER, WITH THE BALANCE QUANITY OF AT LEAST ONE COMONOMER WHICH IS COPOLYCONDESABLE WITH THE TERPHTHALATE, IN TH PRESENCE OF A POLYCONDENSATION CATALYST, CHARACTERIZED IN THAT THE POLYCONDENSATION CATALYST AT LEAST ONE ALKALINE SUBSTANCE SELECTED FROM THE GROUP CONSISTING OF ALKALI METALS, AND HYDRIES, HYDROXIDES, OXIDES ALCOHOLATES, AND INORGANIC AND ORGANIC ACID SALTS OF ALKALI METALS.
Inventors
- 👤 Kenichi Tanabe
- 👤 Hirozo Segawa
- 👤 Kazuo Itoi
Bibliographic Details
Claims Analysis
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