TY  - JOUR
A1  - Miasnikova, Anna
A1  - Laschewsky, André
T1  - Influencing the phase transition temperature of poly(methoxy diethylene glycol acrylate) by molar mass, end groups, and polymer architecture
JF  - Journal of polymer science : A, Polymer chemistry
N2  - The easily accessible, but virtually overlooked monomer methoxy diethylene glycol acrylate was polymerized by the RAFT method using monofunctional, difunctional, and trifunctional trithiocarbonates to afford thermoresponsive polymers exhibiting lower critical solution temperature-type phase transitions in aqueous solution. The use of the appropriate RAFT agent allowed for the preparation and systematic variation of polymers with defined molar mass, end-groups, and architecture, including amphiphilic diblock, symmetrical triblock, and triarm star-block copolymers, containing polystyrene as permanently hydrophobic constituent. The cloud points (CPs) of the various polymers proved to be sensitive to all varied parameters, namely molar mass, nature, and number of the end-groups, and the architecture, up to relatively high molar masses. Thus, CPs of the polymers can be adjusted within the physiological interesting range of 2040 degrees C. Remarkably, CPs increased with the molar mass, even when hydrophilic end groups were attached to the polymers.
KW  - water-soluble polymers
KW  - diblock copolymers
KW  - triblock copolymers
KW  - star-block copolymers
KW  - reversible addition fragmentation chain transfer (RAFT)
KW  - LCST
KW  - stimuli-sensitive polymers
Y1  - 2012
U6  - https://doi.org/10.1002/pola.26116
SN  - 0887-624X
VL  - 50
IS  - 16
SP  - 3313
EP  - 3323
PB  - Wiley-Blackwell
CY  - Hoboken
ER  - 
TY  - JOUR
A1  - Miasnikova, Anna
A1  - Benitez-Montoya, Carlos Adrian
A1  - Laschewsky, André
T1  - Counterintuitive photomodulation of the thermal phase transition of poly(methoxy diethylene glycol acrylate) in aqueous solution by trans-cis isomerization of Copolymerized Azobenzenes
JF  - Macromolecular chemistry and physics
N2  - The non-ionic monomer (methoxy diethylene glycol) acrylate is copolymerized with its azodye-functionalized acrylate analogue using reversible addition-fragmentation chain transfer (RAFT) polymerization. Copolymerization is increasingly difficult with increasing amounts of the azo-dye-bearing monomer. The resulting water-soluble polymers are thermosensitive, exhibiting lower critical solution temperature (LCST) behavior, which can be modulated by the photoinduced trans-cis isomerization of the dye. While already small contents of the hydrophobic azobenzene group reduce the phase-transition temperatures of the copolymers strongly, photoisomerization of the apolar trans-state to the more-polar cis-state has only a small effect, and decreases rather than increases the cloud points.
KW  - azobenzene
KW  - photoisomerization
KW  - statistical copolymers
KW  - thermoresponsive materials
KW  - water-soluble polymers
Y1  - 2013
U6  - https://doi.org/10.1002/macp.201300203
SN  - 1022-1352
VL  - 214
IS  - 13
SP  - 1504
EP  - 1514
PB  - Wiley-VCH
CY  - Weinheim
ER  -