Control over controlled radical polymerization processes

摘要

A procedure for improved temperature control in controlled radical polymerization processes is disclosed. The procedure is directed at controlling the concentration of the persistent radical in ATRP and NMP polymerizations procedures and the concentration of radicals in a RAFT polymerization process by feeding a reducing agent or radical precursor continuously or intermittently to the reaction medium through one of more ports.

主权项

1. A polymerization process, comprising:
i) introducing one or more free radically polymerizable monomers into a system initially comprising:
a) at least one transition metal catalyst; andb) an atom transfer radical polymerization initiator; and ii) polymerizing the one or more free radically polymerizable monomers by feeding a free radical initiator into the system to regenerate the at least one transition metal catalyst at a controlled rate to minimize uncontrolled polymerization reactions;wherein the molar ratio of the at least one transition metal catalyst to the atom transfer radical polymerization initiator is less than 0.10.