TY - JOUR
T1 - Contributions of hard and soft blocks in the self-healing of metal-ligand-containing block copolymers
AU - Bose, Ranjita K.
AU - Enke, Marcel
AU - Grande, Antonio M.
AU - Zechel, Stefan
AU - Schacher, Felix H.
AU - Hager, Martin D.
AU - Garcia, Santiago J.
AU - Schubert, Ulrich S.
AU - van der Zwaag, Sybrand
PY - 2017/8/1
Y1 - 2017/8/1
N2 - The main aim of this work is to study the respective contribution of the hard and soft blocks of a metal-ligand containing block copolymer to the self-healing behavior. To this aim, different block copolymers containing terpyridine were synthesized using reversible addition-fragmentation chain transfer (RAFT) polymerization. These block copolymers consisted of polystyrene as the hard block, n-butyl acrylate (BA) as soft block and terpyridine units as the ligand moiety placed at different locations in the soft block. These block copolymers were complexed with manganese(II) chloride to introduce transient crosslinks and, thus, self-healing behavior. Homopolymers with the hard and soft block only were also synthesized and tested. A quasi-irreversible crosslinking, i.e. by using nickel(II) nitrate, was performed in order to study the dynamics of the permanently (strongly) crosslinked network. Rheological master curves were generated enabling the determination of the terminal flow in these networks and the reversibility of the supramolecular interactions. Additionally, the macroscopic scratch healing behavior and the molecular mobility of the polymer chains in these supramolecular networks were investigated. A kinetic study of the scratch healing was performed to determine the similarities in temperature dependence for rheological relaxations and macroscopic scratch healing. In our previous work, we have explored the effect of strength of the reversible metal-ligand interaction and the effect of changing the ratio of hard to soft block. This work goes further in separating the individual contributions of the hard and soft blocks as well as the reversible interactions and to reveal their relative importance in the complex phenomenon of scratch healing.
AB - The main aim of this work is to study the respective contribution of the hard and soft blocks of a metal-ligand containing block copolymer to the self-healing behavior. To this aim, different block copolymers containing terpyridine were synthesized using reversible addition-fragmentation chain transfer (RAFT) polymerization. These block copolymers consisted of polystyrene as the hard block, n-butyl acrylate (BA) as soft block and terpyridine units as the ligand moiety placed at different locations in the soft block. These block copolymers were complexed with manganese(II) chloride to introduce transient crosslinks and, thus, self-healing behavior. Homopolymers with the hard and soft block only were also synthesized and tested. A quasi-irreversible crosslinking, i.e. by using nickel(II) nitrate, was performed in order to study the dynamics of the permanently (strongly) crosslinked network. Rheological master curves were generated enabling the determination of the terminal flow in these networks and the reversibility of the supramolecular interactions. Additionally, the macroscopic scratch healing behavior and the molecular mobility of the polymer chains in these supramolecular networks were investigated. A kinetic study of the scratch healing was performed to determine the similarities in temperature dependence for rheological relaxations and macroscopic scratch healing. In our previous work, we have explored the effect of strength of the reversible metal-ligand interaction and the effect of changing the ratio of hard to soft block. This work goes further in separating the individual contributions of the hard and soft blocks as well as the reversible interactions and to reveal their relative importance in the complex phenomenon of scratch healing.
KW - Block-copolymer
KW - Metallopolymer
KW - Rheology
KW - Self-healing polymer
KW - Supramolecular network
UR - http://www.scopus.com/inward/record.url?scp=85020922675&partnerID=8YFLogxK
UR - http://resolver.tudelft.nl/uuid:63dd89ae-5394-4fd3-8fce-f739ca4bf0a0
U2 - 10.1016/j.eurpolymj.2017.06.020
DO - 10.1016/j.eurpolymj.2017.06.020
M3 - Article
AN - SCOPUS:85020922675
VL - 93
SP - 417
EP - 427
JO - European Polymer Journal
JF - European Polymer Journal
SN - 0014-3057
ER -