Hard confinement systems as effective for photo-RAFT: towards control over molecular weight distribution and morphology
This work highlights the development of a robust and universal route towards gaining control over macromolecule molecular weight, molecular weight distribution and, more importantly, morphology through the implementation of photoiniferter-mediated RAFT (photo-RAFT) carried out using mesoporous mater...
Saved in:
Published in | Polymer chemistry Vol. 12; no. 8; pp. 115 - 1113 |
---|---|
Main Authors | , , , , , , , , , , |
Format | Journal Article |
Published |
02.03.2021
|
Online Access | Get full text |
Cover
Loading…
Summary: | This work highlights the development of a robust and universal route towards gaining control over macromolecule molecular weight, molecular weight distribution and, more importantly, morphology through the implementation of photoiniferter-mediated RAFT (photo-RAFT) carried out using mesoporous materials varying in the composition, pore arrangement, and pore diameters (metal-organic framework SBA-15 powder
d
= 5-15 nm, silica SiO
2
templates
d
= 4 nm, alumina oxide AAO templates
d
= 10 nm). In fact, the application of these matrices that can act as
nanoreactors
for
in situ
UV-irradiated photo-RAFT of both commercial methyl methacrylate (more-activated monomer) and the synthesized
N
-vinyl-1,2,4-triazolium-based ionic liquid (less-activated monomer) is a key aspect of our approach. The collected data allowed us to probe the influence of the structural features of
nanoreactors
(
i.e.
, transparency, porosity, roughness, and acidity) as well as confinement-related effects connected to variation in free volume and surface interactions on the polymerization path and properties of the produced ionic and non-ionic polymers. It was found that the application of all tested
nanoreactors
ensures greater control over photo-RAFT than analogous batch systems (macroscale photo-RAFT). However, running the reaction in mesoporous AAO templates offered by far the best control over the course of photo-RAFT of both the less-activated monomer (LAM) and the more-activated monomer (MAM) irrespective of the type of selected RAFT agent (
switchable
) (carbamodithioate
vs.
trithiocarbonate), their properties and, more importantly, the yield of the recovered polymers.
Herein an alternative strategy to tune polymer dispersity and morphology was developed for photoiniferter-mediated RAFT giving well-defined ionic and non-ionic nanomaterials. |
---|---|
Bibliography: | 10.1039/d0py01651a Electronic supplementary information (ESI) available. See DOI |
ISSN: | 1759-9954 1759-9962 |
DOI: | 10.1039/d0py01651a |