Multiresponsive Wettability Switching on Polymer Surface: Effect of Surface Chemistry and/or Morphology Tuning

Abstract

The design of responsive surfaces with reversible and fast wettability switching by external control represents one of the most urgent challenges in the surface and interfaces sciences. Especially surfaces responding to more than one stimulus are expected to find even broader range of applications. In this paper, a multiresponsive polymer surface is proposed and investigated that is able to respond to the pH, temperature, and electric field. The surface triggering is subdivided into chemically‐based (pH and temperature) and morphologically‐based (application of electric field). The various combinations of three external triggering are applied separately, conjunctively, or adversarily for detailed investigation of their joint action effect. It is found that the most significant changes in wettability switching are achieved by the simultaneous combination of the reversible chemistry and morphology switching. Oppositely, the utilization of the wettability switching through the combination of chemical stimuli produces negative interference of surface response, with the suppression of stimuli efficiency.

Physically Switchable Antimicrobial Surfaces and Coatings: General Concept and Recent Achievements

“…For example, in ref. [150], the surface wettability and morphology were found to be affected by the simultaneous triggering by pH, temperature, and electric field. To reach such multi-responsivity, the combination of PNIPAm/PAA polymers was used (Figure 16).…”

“…In particular, the tuning of flexible film morphology can be achieved by the application of a perpendicular electric field, which induces the surface hydrodynamic instability and wrinkled pattern appearance [145][146][147]. In the common case, this phenomenon was known to be irreversible, but recently the reversible and spatially selective surface morphology tuning was demonstrated, see Figure 12 As an alternative approach, the utilization of electric field can be used for surface geometry switching using the piezo effect [55, [149][150][151][152]. In particular, the grafting of piezoresponsive PVDF/PMMA polymer fibers with fluorinated chemical moieties was reported As an alternative approach, the utilization of electric field can be used for surface geometry switching using the piezo effect [55,[149][150][151][152].…”

“…In the common case, this phenomenon was known to be irreversible, but recently the reversible and spatially selective surface morphology tuning was demonstrated, see Figure 12 As an alternative approach, the utilization of electric field can be used for surface geometry switching using the piezo effect [55, [149][150][151][152]. In particular, the grafting of piezoresponsive PVDF/PMMA polymer fibers with fluorinated chemical moieties was reported As an alternative approach, the utilization of electric field can be used for surface geometry switching using the piezo effect [55,[149][150][151][152]. In particular, the grafting of piezoresponsive PVDF/PMMA polymer fibers with fluorinated chemical moieties was reported to produce the intrinsically hydrophobic surface.…”

“…Subsequent utilization of electric field triggering enables us to switch the surface between water repellent/water adhesive states and reach the smart, externally controlled self-cleaning phenomena (Figure 13). As an alternative approach, the utilization of electric field can be used for surfa geometry switching using the piezo effect [55,[149][150][151][152]. In particular, the grafting of piez responsive PVDF/PMMA polymer fibers with fluorinated chemical moieties was report to produce the intrinsically hydrophobic surface.…”

Azobenzene-Based Ionic Liquid Switches Phase Separation of Poly(N-isopropylacrylamide) Aqueous Solutions as a Molecular Trigger, Leading to UV Shutdown of Ionic Transport

“…Poly­( N -isopropylacrylamide) (PNIPAm) is a fairly well-known thermoresponsive polymer that undergoes lower critical solution temperature (LCST) in aqueous solution and has been widely studied in various fields, such as tissue engineering, sensors, drug release, microfluidics, and ion recognition. − Significant progress has been made on PNIPAm smart materials, such that LCST behaviors of PNIPAm can be controlled by light via copolymerization of an azobenzene-containing monomer with PNIPAm . Light as an external stimulus has distinct advantages on spatial resolution in a contactless manner.…”