Thermal Isomerization Rates of New Azoquinoline-Functionalized Copolymers as a Function of Substitution Patterns.

Area of Science:

• Polymer Chemistry
• Materials Science
• Optoelectronics

Background:

• Side-chain methacrylic copolymers functionalized with azo dyes are crucial for optoelectronic applications.
• Understanding structure-property relationships is key to designing advanced materials.

Purpose of the Study:

• Investigate the impact of chromophore substitution patterns on optical properties and material motion.
• Explore the role of substituents in azo dyes based on 8-hydroxyquinoline.

Main Methods:

• Spectrometry for absorption spectra analysis.
• Quantum-chemical time-dependent density functional theory (TD-DFT) calculations.
• Thermal stability analysis of cis isomers for molecular motion observation.

Main Results:

• Substituent character and pattern influence excited/ground state dipole moments and HOMO-LUMO gap.
• These factors dictate bathochromic shifts in absorption spectra.
• Two species involved in thermal isomerization were identified, correlating with absorption shifts and rates.

Conclusions:

• Substituents play a dual role in tuning optical properties and thermal relaxation kinetics.
• Findings provide insights for designing azo-functionalized polymers with tailored photoresponsive behaviors.
• Potential for advanced applications in optoelectronics through rational design.