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US 5,962,605 AGranted
High molecular weight polystyrene production by vinyl acid catalyzed free radical polymerization
AssigneeThe Dow Chemical Company
InventorsDuane B. Priddy, Virginia A. Dais
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Abstract
The present invention is a free radical bulk polymerization process for the preparation of high molecular weight polymers from vinyl aromatic monomers, characterized in that the polymerization is conducted in the presence of a vinyl acid containing either a sulfur or phosphorus atom within the acid functional group.
Claims15
A bulk polymerization process comprising:
- a) partially polymerizing a monomer composition consisting essentially of a vinyl aromatic monomer, in the presence of a free radical initiator under conditions such that a mixture of a low molecular weight polymer and unreacted vinyl aromatic monomer is produced, and
- b) further polymerizing the mixture in the presence of a sulfur or phosphorus containing vinyl acid selected from the formulas:
- ##STR3## wherein X is O and n is either 0 or 1;
- Y is H, methyl or phenyl;
- Z is C.sub.1 -C.sub.6 alkyl, aryl or O--Y;
- and R is --C(.dbd.O)CH.sub.2 CH(Y)--, --C(.dbd.O)NHCH.sub.2 CH(Y)--, phenyl or a direct bond, and wherein the sulfur containing vinyl acid is present in amounts of from 25 to 200 ppm and the phosphorus containing vinyl acid is present in amounts of from 500 to 20,000 ppm;
- such that a high Mw polymer is produced.
4 more elements
A bulk polymerization process comprising:
- a) partially polymerizing a monomer composition consisting essentially of a vinyl aromatic monomer, in the presence of a sulfur or phosphorus containing vinyl acid selected from the formulas:
- ##STR4## wherein X is O and n is either 0 or 1;
- Y is H, methyl or phenyl;
- Z is C.sub.1 -C.sub.6 alkyl, aryl or O--Y;
- and R is --C(.dbd.O)CH.sub.2 CH(Y)--, --C(.dbd.O)NHCH.sub.2 CH(Y)--, phenyl or a direct bond, and wherein the sulfur containing vinyl acid is present in amounts of from 25 to 200 ppm and the phosphorus containing vinyl acid is present in amounts of from 500 to 20,000 ppm, such that a mixture of a high Mw polymer and unreacted vinyl aromatic monomer is produced, and
- b) further polymerizing the mixture in the presence of a free radical initiator under conditions such that a low molecular weight polymer is produced.
3 more elements
Dependencies are inferred from the claim text.