| 摘要 |
The method of producing modified ethyl polyterephthalate with the general formula presented in the figure, where R refers to a hydrogen atom or methyl group, n refers to a positive integer, x and y refer to numbers higher than 1, while the quotient of ny to nx is equal to 0.1 to 4. Characterized in that: Large-molecule ethylene polyterephthalate or its oligomers are subjected to synthesis with aliphatic poly (α-hydroxycarboxylic acids) or cyclic dimers of aliphatic α-hydroxycarboxylic acids, in the atmosphere of a neutral gas, at the temperature of 473-558 K, preferably 538-535 K. At least the final stage of the synthesis is carried out at lowered pressure, preferably under 67 Pa. The weight ratio of the large-particle ethylene polyterephthalate or its oligomers to aliphatic poly (α-hydroxycarboxylic acids) or cyclic dimers of aliphatic α-hydroxycarboxylic acids is lower than 100:5. It should be preferably within the range between 100:15 and 100:200.
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