2.3 Sonication and Mechanical Stress Responsive Gels
As for two kinds of important physical forces, ultrasound and mechanical stress
have efficiently affected and trigged the smart supramolecular gels on the
self-assembly processes [89, 90]. Generally, moderate sonication and mechanical
stress can modulate the molecular configuration or the self-assembly processes, but
not change or destroy the chemical structure of gelator [91, 92]. The mechanical
stimulus can be used to overcome the activation barrier or offer access to more
viable aggregate pathways in kinetically disfavoured self-assembly. In the
physical-stimulus-responsive gels, the balance between non-covalent interactions
plays a pivotal role in the formation of nano/microarchitectures, and have been
explored applications in many fields, such as wettability switches, hybrid materials,
pollutant removal [89, 93–95].
Fig. 2.18 a Structure and b photochemical interconversions among the four photoisomeric
structures of FG-DTE 26
2.3 Sonication and Mechanical Stress Responsive Gels
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