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US 4,304,886 AGranted
Mixed coupling agent process
AssigneeShell Oil Company
InventorsArthur R. Bean, Jr., Glenn R. Himes
Life of this patent
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Abstract
Lithium metal-terminated polymers of one or more alkadienes and of one or more monoalkenyl arenes are coupled by reaction with a mixture of two different coupling agents having different functionality.
Claims7
A process for producing a branched polymer having an average functionality of about X arms comprising reacting a living lithium-terminated polymer having the polymer P-Li with a mixture of m moles of a first coupling agent and n moles of a second coupling agent wherein:
- (a) P is selected from the group consisting of polymer chains of one or more alkadienes having 4-12 carbon atoms and copolymers chains of one or more alkadienes having 4-12 carbon atoms and one or more monoalkenyl arenes of 8-18 carbon atoms having the alkenyl radical attached to an arene ring carbon atom;
- (b) said first coupling agent has a functionality of about Y;
- (c) said second coupling agent has a functionality of about Z;
- (d) the functionality values of X, Y and Z are all different;
- and
- (e) the amounts m and n are employed such that (m times Y) plus (n times Z) divided by (m+n) has a value between about 0.8X and 1.2X.
3 more elements
Dependencies are inferred from the claim text.