6533b856fe1ef96bd12b30dd
RESEARCH PRODUCT
Core-Shell Microgels with Switchable Elasticity at Constant Interfacial Interaction.
Astrid DrechslerMaximilian SeussWilli SchmolkeAndreas FeryAndreas FerySebastian Seiffertsubject
Phase transitionMaterials scienceAtomic force microscopyMicrofluidicsPolyacrylamideModulus02 engineering and technology010402 general chemistry021001 nanoscience & nanotechnology01 natural sciences0104 chemical sciencesCore shellchemistry.chemical_compoundchemistrySelf-healing hydrogelsGeneral Materials ScienceComposite materialElasticity (economics)0210 nano-technologydescription
Hydrogels based on poly(N-isopropylacrylamide) (pNIPAAm) exhibit a thermo-reversible volume phase transition from swollen to deswollen states. This change of the hydrogel volume is accompanied by changes of the hydrogel elastic and Young's moduli and of the hydrogel interfacial interactions. To decouple these parameters from one another, we present a class of submillimeter sized hydrogel particles that consist of a thermosensitive pNIPAAm core wrapped by a nonthermosensitive polyacrylamide (pAAm) shell, each templated by droplet-based microfluidics. When the microgel core deswells upon increase of the temperature to above 34 °C, the shell is stretched and dragged to follow this deswelling into the microgel interior, resulting in an increase of the microgel surficial Young's modulus. However, as the surface interactions of the pAAm shell are independent of temperature at around 34 °C, they do not considerably change during the pNIPAAm-core volume phase transition. This feature makes these core-shell microgels a promising platform to be used as building blocks to assemble soft materials with rationally and independently tunable mechanics.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2016-06-20 | ACS applied materialsinterfaces |