ma6b01827_si_001.pdf (494.66 kB)
RAFT Macro-Surfmers and Their Use in the ab Initio RAFT Emulsion Polymerization To Decouple Nanoparticle Size and Polymer Molecular Weight
journal contribution
posted on 2016-11-11, 16:50 authored by Umberto
Capasso Palmiero, Azzurra Agostini, Simone Gatti, Mattia Sponchioni, Viola Valenti, Lucia Brunel, Davide MoscatelliPolymeric
nanoparticles (NPs) are highly engineered nanoemulsions
with applications in several fields. The control over NP surface chemistry,
size (Dn), and molecular weight (MW) of the polymer they are made
up of plays a paramount role in the optimization of their end-use
performance. In this work, the theoretical basis to decouple the dependence
between the NP Dn and MW has been presented, and an operative way
has been demonstrated via ab initio reversible addition–fragmentation
chain transfer (RAFT) emulsion polymerization (AIREP), a “living”
heterogeneous process that adopts RAFT macro-surfmers: macromolecular
chain transfer agents (CTA) produced via RAFT polymerization of amphiliphic
monomers, such as surfmers. The possibility of obtaining the desired
length of the lipophilic block or the length of the whole block copolymer
and the NP Dn by choosing the correct length of the RAFT macro-surfmer
has been assessed. It has been discovered that a wide range of Dn
and MW can be achieved, but not very big NPs with very low copolymer
MW; this limit is consistent with the physical and geometric constraints
of the system.