Star polymers and process for the preparation thereof
AssigneeThe University of Akron
InventorsLewis J. Fetters, Le-Khac Bi
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Abstract
Disclosed is a series of star polymer products having at least three polymeric arms which radiate from a nucleus having at least two molecules of a linking compound. The polymeric arms may be copolymers of conjugated dienes and monovinyl aromatic compounds and/or homopolymers of either monomer. A novel process for the preparation of the polymer products includes the steps of forming the polymer arms with an organometallic initiator to form polymers terminated by an active chain end and thereafter forming a nucleus with the simultaneous linking of the active chain ends thereto. The nucleus is formed from at least two molecules of a linking compound each having at least two functional groups.
Claims21
A polymer product comprising:
- a nucleus having more than one molecule of m-divinyl-benzene;
- and,
- at least three polymeric arms linked to said nucleus, wherein said polymeric arms are selected from the group consisting of homopolymers and copolymers of conjugated diene monomers and block copolymers of conjugated diene and monovinyl aromatic monomers wherein said conjugated diene block is linked to said nucleus.
A polymer product having at least two star polymers joined together wherein each said star polymer comprises:
- a nucleus having more than one molecule of a linking compound;
- and,
- at least three polymeric arms linked to said nucleus, wherein said polymeric arms are selected from the group consisting of homopolymers and copolymers of conjugated diene monomers, monovinyl aromatic monomers and combinations thereof;
- and,
- wherein said star polymers are joined at said nuclei by a linking agent selected from the group consisting of phosgene, silicon tetrachloride and dihalo silanes.
A process for the preparation of a polymer product having at least two star polymers joined together wherein each said star comprises a nucleus and at least three polymeric arms extending from said nucleus, comprising the steps of:
- preparing said polymeric arms from monomers selected from the group consisting of conjugated dienes and monovinyl aromatic compounds with an organometallic initiator so as to form polymers terminated by an active chain end;
- forming said nucleus while simultaneously linking said active chain ends thereto by
- adding to said polymeric arms an organic linking compound having at least two functional groups wherein the ratio of said linking compound to said active chain ends is at least 2.4:1;
- and,
- joining at least two of said star polymers at said nuclei by a linking agent selected from the group consisting of phosgene, silicon tetrachloride and dihalo silanes.
Dependencies are inferred from the claim text.