Polyesterification of 1 4- and 1 5-diols
Abstract
Abstract THERE IS PROVIDED A NOVEL PROCESS FOR THE PRODUCTION OF A POLYESTER WHEREIN THE PRODUCTION OF UNDESIRED CYCLIC BYPRODUCTS IS MINIMIZED. IN SAID PROCESS A MIXTURE COMPRISED OF AT LEAST ONE 1,4- OR 1,5-DIOL AND A DICARBOXYLICACID ESTER IS SUBJECTED TO A TEMPERATURE OF ABOUT 140 TO ABOUT 230 DEGREES CENTIGRADE AND A VACUUM OF FROM ABOUT 15 TO ABOUT 760 MILLIMETERS OF MERCURY ABSOLUTE FOR FROM ABUT 30 TO ABOUT 200 MINUTES, A VACUUM OF LESS STHAN ABOUT 15 MILLIMMETES OF MERCURY IS THAN SLOWLY IMPOSED UPON IT, AND THEREAFTER THE TEMPERATURE OF THE MIXTURE IS RAISED TO FROM ABOUT 230 TO ABOUT 300 DEGREES CENTIGRADE; AND THE MITRURE IS MAINTAINED UNDER THESE TEMPERATURE AND PRESSURE CONDITION UNTIL A POLYMER WITH THE DESIRED RELATIVE VISOSITY IS FORMED. THIS PROCESS MINIMIZES THE AMOUNT OF CYCLIC BY-PRODUCTS PRODUCED.
Inventors
- 👤 Marvin L Doerr
- 👤 Luis R Vizurraga
Bibliographic Details
Claims Analysis
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