Abnormal fast dehydration and rehydration of light- and thermo-dual-responsive copolymer films triggered by UV radiation

Abstract

Abnormal fast dehydration and rehydration of light- and thermo-dual-responsive copolymer films of poly(oligo(ethylene glycol) methyl ether methacrylate-co-6-(4-phenylazophenoxy)hexyl acrylate), abbreviated as P(OEGMA300-co-PAHA), are triggered by UV radiation.

Kinetics of UV Radiation-Induced Fast Collapse and Recovery in Thermally Cycled and Rehydrated Light- and Thermo- Double-Responsive Copolymer Films Probed by In Situ Neutron Reflectivity

“…The details for the monomers and chemical agents used in our present investigation can be found in the Supporting Information. The details for the synthesis of the light-responsive monomer PAHA and double-responsive copolymer P­(OEGMA 300 - co -PAHA), as well as the molecular weight and polydispersity index (PDI) of P­(OEGMA 300 - co -PAHA), can be found in our previous publication . The synthesis and chemical structure of the P­(OEGMA 300 - co -PAHA) can be found in Figure .…”

Effect of Magnesium Salts with Chaotropic Anions on the Swelling Behavior of PNIPMAM Thin Films

“…Stimuli-responsive polymers open a wide field of applications due to their unique properties. − For most applications, the polymers require a certain mechanical stability while exhibiting a fast response to the stimuli. This balance between stability and responsiveness can be achieved by using thin films , and is especially needed when designing nanodevices such as nanoswitches or gas sensors. − The response of thin films fabricated from stimuli-responsive polymers is shown to derive often from a conformational change, which can be achieved by temperature, − light, , ionic strength, , pressure, pH, , or by changing the environment. , An example for a thermoresponsive polymer is poly­( N -isopropylmethacrylamide) (PNIPMAM), which features a lower critical solution temperature in water at about 44 °C. , Moreover, PNIPMAM films are capable of temperature-modulated swelling under the influence of surrounding water vapor and exhibit cononsolvency behavior in various water-organic solvent mixtures. − These properties make PNIPMAM a promising candidate for application in nanodevices, such as nanoswitches or humidity sensors. , …”

“…This balance between stability and responsiveness can be achieved by using thin films 6,7 and is especially needed when designing nanodevices such as nanoswitches or gas sensors. 8−12 The response of thin films fabricated from stimuli-responsive polymers is shown to derive often from a conformational change, which can be achieved by temperature, 13−15 light, 16,17 ionic strength, 18,19 pressure, 20 pH, 21,22 or by changing the environment. 23,24 An example for a thermoresponsive polymer is poly(N-isopropylmethacrylamide) (PNIPMAM), which features a lower critical solution temperature in water at about 44 °C.…”

Optical Properties of Slot‐Die Coated Hybrid Colloid/Cellulose‐Nanofibril Thin Films

“…For determining optical constants of thin films, namely refractive index and attenuation coefficient, ellipsometry, and white light interferometry are the methods of choice. [ 38–41 ]…”

“…For determining optical constants of thin films, namely refractive index and attenuation coefficient, ellipsometry, and white light interferometry are the methods of choice. [38][39][40][41] X-ray scattering methods are ideally used to determine porosity and colloidal arrangement. In amorphous colloidal crystals, transmission small-angle X-ray scattering (SAXS) allows for determining the spacing of the colloids.…”