Polysiloxane-Modified Tetraphenylethene: Synthesis, AIE Properties, and Sensor for Detecting Explosives

Area of Science:

• Materials Science
• Organic Chemistry
• Polymer Science

Background:

• Tetraphenylethene (TPE) derivatives are known for their aggregation-induced emission (AIE) properties.
• Polysiloxanes offer unique properties like thermal stability and processability.
• Combining TPE with polysiloxanes could lead to novel functional materials.

Purpose of the Study:

• To synthesize polysiloxane-modified tetraphenylethene (PTPESi).
• To investigate the photophysical properties and stability of PTPESi.
• To evaluate PTPESi as a sensor for vapor-phase explosive detection.

Main Methods:

• Synthesis of PTPESi via attachment of TPE units onto methylvinyldiethoxylsiloxane followed by polycondensation.
• Characterization of photophysical properties, including fluorescence intensity and emission peak width.
• Assessment of thermal and morphological stability through annealing experiments.
• Evaluation of sensor performance for explosive detection based on fluorescence quenching efficiency and reversibility.

Main Results:

• Successful synthesis of PTPESi with retained TPE aggregation-induced emission characteristics.
• PTPESi demonstrated high thermal and morphological stability, with minimal changes after annealing.
• The HOMO and LUMO energy levels are primarily localized on the TPE moieties.
• PTPESi films exhibited high fluorescence quenching efficiency and good reversibility in detecting vapor-phase explosives.

Conclusions:

• Polysiloxane modification minimally impacts TPE's photophysical and AIE properties.
• PTPESi possesses excellent thermal and morphological stability.
• PTPESi is a promising material for sensitive and reversible vapor-phase explosive detection.