Thermally responsive AIE-active polyurethanes based on a tetraaniline derivative

Area of Science:

• Polymer Chemistry
• Materials Science
• Fluorescent Materials

Background:

• Polyurethanes are versatile polymers with tunable properties.
• Aggregation-induced-emission (AIE) materials offer unique fluorescence characteristics.
• Developing stimuli-responsive fluorescent materials is an active area of research.

Purpose of the Study:

• To synthesize novel polyurethanes incorporating an AIE-active moiety.
• To investigate the impact of structural arrangement on the AIE properties of these polyurethanes.
• To explore the potential of these materials as stimuli-responsive fluorescent sensors.

Main Methods:

• Synthesis of polyurethanes using an AIE-active tetraaniline derivative (NH2-B3-Ani4-NH2) as the hard segment.
• Characterization of AIE features and fluorescence response to thermal treatments (quenching and annealing).
• Differential Scanning Calorimetry (DSC) to analyze structural changes upon thermal treatment.

Main Results:

• Successfully synthesized polyurethanes exhibiting typical AIE behavior.
• Demonstrated that fluorescence intensity is sensitive to heat treatments, with annealing restoring quenched fluorescence.
• Observed changes in DSC melting peaks correlating with structural rearrangements and fluorescence recovery.
• Confirmed temperature-dependent fluorescence characteristics in the synthesized polyurethanes.

Conclusions:

• The structural arrangement significantly influences the AIE properties of polyurethane films.
• The synthesized AIE-active polyurethanes show promise as stimuli-responsive fluorescent materials.
• These materials provide a potential platform for developing advanced fluorescent sensors and devices.