Photoactuation and thermal isomerisation mechanism of cyanoazobenzene-based liquid crystal elastomers.

Phys Chem Chem Phys

Grup de Materials Orgànics, Departament de Química Orgànica, Institut de Nanociència i Nanotecnologia (IN2UB), Universitat de Barcelona, Martí i Franquès 1, E-08028, Barcelona, Spain.

Published: May 2014

4-Alkoxy-4'-cyanoazobenzenes are organic chromophores with great applicability within present nanotechnology. However, the use of such azo dyes for obtaining light-triggered artificial muscle-like actuators remains still unexplored. Achieving further knowledge about the thermal back reaction and isomerisation mechanism for these types of azoderivatives is essential to get photo-actuators with the desired abilities. Despite the push-pull nature of the 4-alkoxy-4'-cyanoazobenzene chromophore, it has been experimentally demonstrated that it isomerises via an inversion mechanism. The opto-mechanics of the prepared elastomeric material has also been investigated. For this system, a maximum opto-mechanical response of ca. 2.5 kPa has been registered, which is independent of the working temperature of the photoactuator.

Download full-text PDF

Source
http://dx.doi.org/10.1039/c4cp00446aDOI Listing

Publication Analysis

Top Keywords

isomerisation mechanism
8
photoactuation thermal
4
thermal isomerisation
4
mechanism cyanoazobenzene-based
4
cyanoazobenzene-based liquid
4
liquid crystal
4
crystal elastomers
4
elastomers 4-alkoxy-4'-cyanoazobenzenes
4
4-alkoxy-4'-cyanoazobenzenes organic
4
organic chromophores
4

Similar Publications

Experimental and DFT Studies of Intermolecular Interaction-Assisted Oxindole Cyclization Reaction of Di-t-butyl 2-Aminophenyl-2-methyl Malonate.

Chem Pharm Bull (Tokyo)

January 2025

Department of Life Science and Biotechnology, Faculty of Chemistry, Materials and Bioengineering, Kansai University, 3-3-35 Yamate-cho, Suita, Osaka 564-8680, Japan.

Density functional theory calculations on the cyclization of di-t-butyl 2-(2-aminophenyl)-2-methyl malonate (1) to t-butyl 3-methyloxindole-3-carboxylate (2) reveal that acetic acid-assisted protonation of the carbonyl oxygen atom reduces the activation Gibbs free energy significantly lower than methanol-assisted pathways. Experimental data confirm that reaction concentration plays a pivotal role in oxindole formation. Experimental results also indicate distinct reaction mechanisms at low and high concentrations.

View Article and Find Full Text PDF

Polyesters featuring a linear topology and in-chain 1,3-cyclobutane rings, synthesized via ring-opening polymerization (ROP) of 2-oxabicyclo[2.1.1]hexan-3-one (4R-BL, R = Bu, Ph) through a coordination-insertion mechanism, display excellent thermal and hydrolytic stability, making them promising candidates for sustainable circular materials.

View Article and Find Full Text PDF

The copolymerization of ethylene with polar monomers presents a significant challenge. While palladium catalysts have shown promise, nickel catalysts are more economical but suffer from poor activity. Previous studies suggest that the isomerization step involved in the nickel-catalyzed polymerization may influence the catalyst activities.

View Article and Find Full Text PDF

Molecular Mechanism Behind the Capture of Fluorinated Gases by Metal-Organic Frameworks.

Nanomicro Lett

January 2025

College of Environmental Science and Engineering, State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Siping Rd 1239, Shanghai, 200092, People's Republic of China.

Fluorinated gases (F-gases) play a vital role in the chemical industry and in the fields of air conditioning, refrigeration, health care, and organic synthesis. However, the direct emission of waste gases containing F-gases into the atmosphere contributes to greenhouse effects and generates toxic substances. Developing porous materials for the energy-efficient capture, separation, and recovery of F-gases is highly desired.

View Article and Find Full Text PDF

Loz1 is a zinc-responsive transcription factor in fission yeast that maintains cellular zinc homeostasis by repressing the expression of genes required for zinc uptake in high zinc conditions. Previous deletion analysis of Loz1 found a region containing two tandem CH zinc-fingers and an upstream "accessory domain" rich in histidine, lysine, and arginine residues to be sufficient for zinc-dependent DNA binding and gene repression. Here we report unexpected biophysical properties of this pair of seemingly classical CH zinc fingers.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!