Patent ID: 6197905
Filing Date: 2001-03-06
Classification: C08F

Abstract:
An improved process for the production of polymer or oligomer of controllably reduced molecular weight by the/free radical polymerization of monomers in the presence of an initiator and a chain transfer agent which is present in an effective amount to control the molecular weight of said polymer or oligomer: wherein said chain transfer agent terminates the growth of the polymer chain by addition to the propagating polymer radical followed by expulsion of a radical which then initiates another polymer chain;wherein the improvement comprises employing a chain transfer agent having the formula ##STR5##whereinR.sup.1 is selected from the group consisting of cyano, carboxyl, optionally substituted alkoxycarbonyl, and phenyl substituted with a substituent selected from the group consisting of hydroxyl, carboxyl, amino, epoxy, and halogen;R.sup.2, excluding oxetane, is C.sub.1 -C.sub.32 -alkyl, C.sub.2 -C.sub.32 -alkenyl, C.sub.2 -C.sub.32 -alkynyl, or saturated, unsaturated or aromatic carbocyclic 3 to 14 atom ring, said R.sup.2 being optionally substituted with a reactive or a non-reactive substituent, said reactive substituent being selected from the group consisting of hydroxy, amino, halogen, phosphonate, trialkylsilyl, allyl, cyano, epoxy, carboxylic acid, and carboxylic acid ester, said non reactive substituent being selected from the group consisting of alkoxy and alkyl.