Process for producing novel block alkylene polycarbonate copolymers
AssigneeAir Products and Chemicals, Inc.
InventorsJoseph G. Santangelo, James J. Weber, Richard G. Sinclair
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Abstract
The present invention is a novel class of block copolymers and a process of making the same. An alkylene oxide is reacted with CO.sub.2 in an organic solvent in the presence of an organometallic catalyst to form a polyalkylene carbonate. A second alkylene oxide is subsequently added without the addition of catalyst. The resulting product is a block copolymer comprising distinct, covalently linked, alkylene carbonate blocks.
Claims25
A process for producing a block copolymer having at least two distinct, covalently linked alkylene carbonate blocks and having the structural formula:
- ##STR3## wherein R.sub.1 is H, CH.sub.3, C.sub.2 H.sub.5, or C.sub.6 H.sub.5 ;
- R.sub.2 and R.sub.3 are independently H, CH.sub.3, C.sub.2 H.sub.5 or R.sub.2 and R.sub.3 together form a six member ring;
- and x and y are both integers from 50 to 10,000 said process comprising:
- (a) copolymerizing an alkylene oxide with excess carbon dioxide in a reaction vessel in the presence of an organometallic catalyst until said polymerization reaches equilibrium;
- and
- (b) subsequently adding a second alkylene oxide to the reaction vessel to form said block copolymer.
A block copolymer having at least two distinct covalently linked alkylene carbonate blocks, and having the structural formula:
- ##STR4## wherein R.sub.1 is H, CH.sub.3, C.sub.2 H.sub.5 or C.sub.6 H.sub.5 ;
- R.sub.2 and R.sub.3 are independently H, CH.sub.3, C.sub.2 H.sub.5 or R.sub.2 and R.sub.3 together form a six member ring;
- and x and y are both integers from 50 to 10,000.
Dependencies are inferred from the claim text.