Cellulose nanocrystal-grafted multi-responsive copolymers containing cleavable o-nitrobenzyl ester units for stimuli-stabilization of oil-in-water droplets

Tajmoradi, Zeinab; Roghani‐Mamaqani, Hossein; Salami‐Kalajahi, Mehdi

doi:10.1016/j.cej.2020.128005

Cited by 30 publications

(23 citation statements)

References 75 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…To develop the kinetics equation and also additional parameters, the initial kinetics curves were fitted by using the standard equations of OriginLab software (Professional 2017). The kinetics of SP to MC and MC to SP isomerizations were fitted by using Box Lucas 1 and also ExpDec1 models, respectively, which resulted in exponential equations shown in eqn ( 4) and (5).…”

Section: Investigation Of Photochromism Kinetics and Fatigue Resistancementioning

confidence: 99%

“…1,2 Considering the chemical structure and functionality of the nanoparticles, a wide range of variations in color, fluorescence emission, hydrophilicity and hydrophobicity, and hydrodynamic diameter could be observed upon induction of light, pH, temperature, CO 2 bubbling, and also mechanical stress. [3][4][5][6] Photochromic and fluorescent nanoparticles have received a great deal of attention because of some significant advantages of light as an external stimulus, including controllability out of the system, adjustability in intensity, non-destructivity, and accessibility in any time and place. [7][8][9] Photochromic organic molecules as common lightresponsive materials have extensively been used in the preparation of stimuli-chromic polymer nanoparticles by their chemical or physical incorporation into the polymer matrix.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Development of optical chemosensors based on photochromic polymer nanocarriers

et al. 2022

Self Cite

View full text Add to dashboard Cite

show abstract

Section: Investigation Of Photochromism Kinetics and Fatigue Resistancementioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Development of optical chemosensors based on photochromic polymer nanocarriers

et al. 2022

Self Cite

View full text Add to dashboard Cite

show abstract

“…These variations can be chemical, physical, and biological stimuli, such as light, temperature, pH, CO 2 gas, glucose, enzymes, etc. , The main stimuli-responsive polymeric systems are designed as polymer solutions, organo- and hydrogels, surfaces and interfaces, fibers, colloids, and solids. − Light has attracted huge attention because of its easy external triggering; attainability; nondestructive effects on polymeric systems; and modulation in intensity, wavelength, and irradiation time. − Concerning the type of the photoresponsive moieties and their location in the polymer chain, different photoresponsive polymers could be obtained, which show irreversible or reversible reactions upon light irradiation. These reactions finally result in a variation of hydrophilicity by isomerization, cross-linking by dimerization, main chain degradation by cleavage, or block junction breaking in the polymer structure under light irradiation. − Dimerization reactions of these photoresponsive moieties are mostly based on different cycloaddition mechanisms. The [2π + 2π] cycloaddition reaction of two alkenes results in cyclobutane dimer formation between the two molecules .…”

Section: Introductionmentioning

confidence: 99%

Coumarin-Containing Block Copolymers as Carbon Dioxide Chemosensors Based on a Fluorescence Quenching Mechanism

Mardani

Roghani‐Mamaqani

Shahi

et al. 2022

ACS Appl. Polym. Mater.

Self Cite

View full text Add to dashboard Cite

Coumarin-containing stimuli-responsive block copolymers were synthesized via atom transfer radical polymerization (ATRP), which exhibited a sensitivity of fluorescence emission intensity to carbon dioxide by a fluorescence quenching mechanism. Poly(7-acryloyloxy 4-methylcoumarin-r-methyl methacrylate)-b-poly(dimethylaminoethyl methacrylate) (P(CMA-r-MMA)-b-PDMAEMA) with different block lengths were synthesized using a coumarin functional ATRP initiator 7-(2bromoisobutyryloxy)-4-methylcoumarin. The block copolymers were self-assembled into a vesicular morphology in an aqueous medium with the poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA) block in the inner and outer shells and the P(CMA-r-MMA) block in the core. The hydrophilic fraction calculated from proton nuclear magnetic resonance spectra and transmission electron microscopy and optical microscopy images confirmed the self-assembly of the block copolymers to the vesicular morphology in the aqueous medium. The size of the self-assembled structures was studied in different conditions by dynamic light scattering. Ultraviolet−visible spectroscopy showed the presence of coumarin in the structure of vesicles and also its dimerization during light irradiation. An aqueous colloidal dispersion of the vesicular assemblies was used for sensing CO 2 gas in aqueous media using fluorescence spectroscopy. The wall thickness of the vesicles decreased upon CO 2 bubbling, which was accompanied by an increase of their hydrodynamic radius. Therefore, the distance of coumarin moieties increased and subsequently resulted in a decrease in their aggregation state and fluorescence intensity. This process was also reversibly carried out to increase the pH of the medium by N 2 bubbling. Indeed, the prepared fluorescence chemosensor was used for the detection of CO 2 on the basis of the fluorescence quenching mechanism. The chemosensor formed from the block copolymer having the highest amount of PDMAEMA and 7-acryloyloxy-4-methylcoumarin (CMA) showed the highest reversible CO 2 sensing ability at room temperature.

show abstract

“…Stimuli-responsive polymers, which are classified as highly prominent smart materials, respond to induced stimuli by changing their physical and/or chemical characteristics. , These polymers have extensively been investigated because of their response to light, , pH, , temperature, CO 2 , mechanical stress, polarity, and also redox reactions . Light has recently emerged as a fascinating stimulus because it is nondestructive, controllable externally, and its intensity is adjustable .…”

Section: Introductionmentioning

confidence: 99%

Optical Chemosensors based on Spiropyran-Doped Polymer Nanoparticles for Sensing pH of Aqueous Media

et al. 2022

Self Cite

View full text Add to dashboard Cite

Photochromic polymers, which are prepared by the incorporation of photochromic compounds into polymer matrices, show fluorescence emission along with color change under UV light irradiation. Polymer nanoparticles yield high chromic properties at low chromophore loadings, as they have a large surface area to absorb a high level of light irradiation. Particle size is a significant parameter to control optical properties, where the decrease of particle size results in a high light absorption and efficiency of photochromism and fluorescence emission. Reverse atom transfer radical polymerization was used to synthesize methyl methacrylate homopolymer and its copolymers with different comonomers to yield polymers with a narrow molecular weight distribution. Spiropyran was doped to the polymeric nanoparticles during nanoprecipitation to yield photochromic polymer nanoparticles. Particle size below 100 nm for the photochromic nanoparticles was shown by dynamic light scattering. Morphology investigation with microscopic analysis showed spherical morphology for nanoparticles. The photochromic properties of the polymer nanocarriers were studied in both acidic and alkaline media. The results indicated that the pH of the media as well as the copolymer composition significantly affect the optical properties. Therefore, the photochromic polymer nanoparticles could have potential applications as optical pH chemosensors by colorimetric and fluorometric detection mechanisms. The nanoparticles with hydroxyl- or amine-functional groups were shown to be highly efficient for pH chemosensor applications. Finally, photochromic cellulosic papers prepared from the photochromic polymer nanoparticles were highly applicable in the detection of acid vapors.

show abstract

Cellulose nanocrystal-grafted multi-responsive copolymers containing cleavable o-nitrobenzyl ester units for stimuli-stabilization of oil-in-water droplets

Cited by 30 publications

References 75 publications

Development of optical chemosensors based on photochromic polymer nanocarriers

Development of optical chemosensors based on photochromic polymer nanocarriers

Coumarin-Containing Block Copolymers as Carbon Dioxide Chemosensors Based on a Fluorescence Quenching Mechanism

Optical Chemosensors based on Spiropyran-Doped Polymer Nanoparticles for Sensing pH of Aqueous Media

Contact Info

Product

Resources

About