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US 5,684,101 AGranted
Free radical polymerisation process
AssigneeZeneca Limited
InventorsAndrew Victor Graham Muir, John Robert Lawson, David Mark Haddleton
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AssigneeZeneca Limited
InventorsAndrew Victor Graham Muir, John Robert Lawson, David Mark Haddleton
Estimating the term…
Process for the free-radical polymerization of at least one olefinically unsaturated monomer, the polymerization being performed in the presence of a compound for effecting molecular weight control, being a CoII chelate of the following formula: ##STR1## wherein each group X is a divalent group which forms with the two carbon atoms to which it is bonded a pericondensed polycyclic group, being a group having 3 or more carbocyclic rings where the oxime-containing carbocyclic ring has carbon atoms in common with 2 or more of the other rings, the polycyclic group being unsubstituted (apart from the oxime groups) or having at least one hydrocarbyl substituent; and wherein each group Q is independently selected from F, Cl, Br, OH, C.sub.1-12 alkoxy, aryloxy, C.sub.1-12 alkyl and aryl; or two Q groups taken together provide on one or both boron atoms a group --O--(G)--O-- where G is a divalent aryl or alicyclic linking group or an alkylene linking group; or two Q groups taken together on one or both boron atoms provide a 1,5-cyclooctanediyl linking group; or being a CoIII analogue of the cobalt II chelate in which the Co atom is additionally covalently bonded to H, a halide or other anion, or a homolytically dissociable organic group. Novel Co chelates for use in the process are also disclosed.
Process for the free-radical polymerisation of at least one olefinically unsaturated monomer using a free-radical initiator, the polymerisation being performed in the presence of a compound for effecting molecular weight control, wherein the molecular weight control compound is a CoII chelate of the following formula I:
Process according to any one of the preceding claims wherein said pericondensed polycyclic group has carbon atoms in common with 2 or 3 of the other rings.
Process according to any one of the preceding claims wherein said pericondensed polycyclic group is unsubstituted (apart from the oxime groups) or has at least one substituent which is C.sub.1-12 alkyl.
Process according to any one of the preceding claims, wherein the CoII chelate complex has the formula IV:
Process according to any one of the preceding claims wherein each Q is the same and is selected from F, Cl, Br, OH, C.sub.1-12 alkyl and C.sub.1-12 alkoxyl.
Process according to any one of the preceding claims wherein the molecular weight control compound is the CoIII analogue of said CoII chelate in which the Co atom is additionally bonded, in a direction at right angles to the macrocyclic ring system, to H, a halide or other anion, or a homolytically dissociable organic group.
Process according to any one of the preceding claims wherein said cobalt chelate has a further ligand(s) coordinated to the cobalt atom which does not alter the cobalt valency state, said ligand being selected from weakly basic tertiary amines, ethers, alkanols, optionally substituted trialkyl, triaryl, or tri(alkyl/aryl)phosphines and the corresponding alkoxy or arloxy phosphines, and water.
Process according to any one of the preceding claims wherein said polymerisation is a solution polymerisation in organic solvent.
Process according to any one of the preceding claim wherein said at least one olefinically unsaturated monomer is a methacrylic monomer.
Process according to any one of the preceding claims wherein the monomer system employed includes an acid-functional monomer, preferably being one or both of methacrylic acid and acrylic acid.
An oligomer made using a process according to any one of the preceding claims.
Dependencies are inferred from the claim text.