| abstract |
This invention relates to a process for the production of lower molecular weight polymers by free radical-initiated polymerization of unsaturated species characterized by the use of an unsaturated compound of Formula I as a chain transfer agent:wherein R1 and R2 are the same or different and are selected from the group consisting of hydrogen, optionally substituted alkyl, optionally substituted saturated or aromatic carbocyclic or heterocyclic ring, and halogen;X is selected from the group consisting of chlorine, bromine, optionally substituted alkylsulfonyl, and optionally substituted arylsulfonyl,Y is selected from the group consisting of halogen, a polymer chain, and CR3R4Z, wherein R3 and R4 are the same or different and are selected from the group consisting of hydrogen, optionally substituted alkyl, optionally substituted saturated, unsaturated or aromatic carbocyclic or hetercyclic ring, and halogen; andZ is selected from the group consisting of chlorine, bromine, optionally substituted alkylsulfonyl and optionally substituted arylsulfonyl;provided that when X is optionally substituted alkylsulfonyl or optionally substituted arylsulfonyl, Y is not halogen.The invention also relates to various polymers produced by this process and products comprising these polymers. The process of the invention may also be used in the preparation of A-B type block copolymers. |