Dibromomaleimide End Functional
Polymers by RAFT Polymerization
Without the Need of Protecting Groups
- Publication date
- Publisher
Abstract
Polymers bearing the dibromomaleimide (DBM) group as
a functional
chain end have been synthesized by RAFT polymerization. A DBM functional
chain transfer agent (CTA) was utilized to afford well-defined P<sup>t</sup>BA, PMA, and PTEGA, without the requirement of protecting
group chemistry. It was found that RAFT polymerization of NIPAM and
styrene with this CTA was severely retarded/inhibited which is ascribed
to their relatively low propagation rate constants compared to acrylates.
This observation is accounted for by a reversible trapping of propagating
radicals by the DBM group in RAFT polymerizations using a monomer
with low <i>k</i><sub>p</sub>. However, further attempts
to synthesize DBM-terminated P<sup>t</sup>BA and PMA by ATRP using
an analogous initiator were unsuccessful, and broad PDI were observed.
Furthermore, highly efficient postpolymerization functionalization
of DBM-terminated PMA produced by RAFT, with the model compound thiophenol
was also demonstrated