Process of rendering copolymers of maleic anhydride and alkyl vinyl ethers prepared in benzene solvent substantially benzene-free
AssigneeGAF Chemicals Corporation
InventorsMohammed Tazi, Robert B. Login, Nikhil Kundel
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Abstract
Substantially benzene-free copolymers of maleic anhydride and alkyl vinyl ethers having benzene present in an amount of less than about 1 ppm and an alkyl-substituted aromatic hydrocarbon present in an amount of about 2.0 wt. % or less, and a process for rendering a copolymer reaction product of maleic anhydride and an alkyl vinyl ether prepared in benzene solution substantially benzene-free, is described herein.
Claims20
A process of rendering a copolymer reaction product of maleic anhydride and an alkyl vinyl ether prepared in benzene solvent substantially benzene-free which comprises treating the copolymer reaction product while in the wet state with an organic liquid which can swell the copolymer and release residual benzene therefrom.
A process of rendering a copolymer reaction product of maleic anhydride and an alkyl vinyl ether prepared in benzene solvent substantially benzene-free which comprises:
- (a) copolymerizing maleic anhydride and an alkyl vinyl ether in benzene solvent to provide a slurry of a solid copolymer of maleic anhydride and said alkyl vinyl ether in benzene,
- (b) removing the bulk of the benzene solvent to provide copolymer in a wet state containing residual benzene,
- (c) treating the wet state copolymer with an organic liquid to swell the copolymer and release residual benzene therefrom,
- (d) removing residual benzene and said swelling liquid,
- (e) optionally, repeating steps (c) and (d), and
- (f) optionally, drying the thus-treated copolymer.
A process according to claim 12 wherein said organic liquid is an alkyl-substituted aromatic hydrocarbon.
Dependencies are inferred from the claim text.