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US 9,688,818 B2Granted
Poly(ether sulfone)s and poly(ether amide sulfone)s and methods of their preparation
AssigneeInternational Business Machines Corporation
InventorsKrishna M. Bajjuri, Jeannette M. Garcia, James L. Hedrick
Life of this patent
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Abstract
Poly(ether sulfones) (PES) and poly(ether amide sulfones) (PEAS) were prepared from post-consumer polycarbonates and polyesters, respectively, using a single vessel in batch mode (all reactants present when heating was initiated). The depolymerization of the initial polymer occurs concurrently with step growth polymerization to form a product polymer having a number average molecular weight of at least 5000.
Claims20
A method, comprising:
- forming a mixture comprising
- i) a polycarbonate having a repeat unit of formula (2):
- wherein
- Lb is a divalent radical comprising 2 or more carbons,
- ii) a bis-aryl sulfone of formula (4):
- wherein
- each E′ is an independent monovalent radical selected from the group consisting of hydrogen and electron withdrawing groups, and
- each X′ is an independent monovalent leaving group,
- iii) a base comprising a carbonate dianion (CO3−2), wherein the mixture contains between 0.05 mole and 1.0 mole of the base per mole of the bis-aryl sulfone, and
- iv) a solvent;
- and
- heating the mixture at a reaction temperature of about 150° C. to about 250° C. while removing any volatile organic byproducts from the heated mixture using a stream of inert gas, thereby forming a poly(ether sulfone) (PES).
9 more elements
Dependencies are inferred from the claim text.