Process for producing chlorinated butyl rubber
AssigneeArlanxeo Singapore Pte. Ltd.
InventorsGregory J. E. Davidson, Kuruppu Jayatissa
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Abstract
The invention relates to an energy efficient, fast and environmentally favourable process for the preparation of chlorinated butyl rubbers, that uses hypochlorous acid (HOCl) and/or dichlorine monoxide (Cl2O) as halogenating agent. The process comprises reacting a copolymer with hypochlorous acid and/or dichlorine oxide. The copolymer comprises units derived from an isoolefin monomer and units derived from a multiolefin monomer. A preferred isoolefin is isobutene and a preferred multiolefin is isoprene.
Claims20
A process for the preparation of a chlorinated copolymer comprising at least the step of reacting a copolymer comprising
- i) structural units derived from at least one isoolefin monomer and
- ii) structural units derived from at least one multiolefin monomer
- with hypochloric acid and or dichlorine oxide.
A chlorinated copolymer comprising at least
- i) structural units derived from at least one isoolefin monomer and
- ii) structural units derived from isoprene
- wherein the
- the chlorine content of the copolymer is from 0.1 to 4 wt.-%,
- the structural units derived from isoprene are at least partially chlorinated to form exo-methylene and endo-Cl and cis-endo and trans-endo and microstructure units such that the microstructure Index X being the ratio of mol-% (exo-methylene+endo-Cl)/mol-% (cis-endo and trans-endo) as measured by 1H-NMR is from 1.50 to 3.30.
A chlorinated copolymer comprising at least
- i) structural units derived from at least one isoolefin monomer and
- ii) structural units derived from isoprene wherein the copolymer comprises 1-(1-chloromethylethenyl)-2,2,4,4-tetramethylcyclohexane (C1-C13) and 1,1,5,5-tetramethyl-2-(1-chloromethylethenyl)-3-(2,2,4-trimethylpentyl)-cyclohexane (C1-C21) in an amount of together 1000 ppm or less and/or in a ratio (C1-C13)/(C1-C21) of 0.60 or more.
Dependencies are inferred from the claim text.