The development of efficient luminescent materials has attracted much attention since the first discovery of fluorescence in 1565. Inspired by nature and guided by the photophysical principles, scientists have designed and created various luminescent compounds with tunable emission wavelength in the whole visible spectrum or beyond. Unfortunately, most of the traditional organic fluorophores suffer from the self-quenching problem at high concentration or in aggregated state, thus limiting their applications in various fields. On the contrary, aggregation-induced emission (AIE), a novel photophyscial phenomena coined in 2001 by our group, describes the enhanced light emission of some luminogens in the aggregate or solid states. The family of these unique molecules are noted as A...[ Read more ]

The development of efficient luminescent materials has attracted much attention since the first discovery of fluorescence in 1565. Inspired by nature and guided by the photophysical principles, scientists have designed and created various luminescent compounds with tunable emission wavelength in the whole visible spectrum or beyond. Unfortunately, most of the traditional organic fluorophores suffer from the self-quenching problem at high concentration or in aggregated state, thus limiting their applications in various fields. On the contrary, aggregation-induced emission (AIE), a novel photophyscial phenomena coined in 2001 by our group, describes the enhanced light emission of some luminogens in the aggregate or solid states. The family of these unique molecules are noted as AIE luminogens (AIEgens ). After 17 years of AIE research, diverse AIEgens with tunable color and high quantum yields have been synthesized.

To distinguish as practical materials for real-world applications, AIE materials should process excellent properties, especially film forming ability and processability. Therefore, combining AIE research with polymer materials through chemical incorporation or physical doping is a smart approach. In this thesis, I have launched a program for the development of AIE materials by chemical and physical approaches, as well as explored their advanced functionalities and applications in aggregated or film states. Besides the direct application of their strong emission in aggregated or solid state, great endeavors have been devoted to utilize the underlying mechanism of AIEgens, restriction of intramolecular motion, and employ them as perfect fluorescent probes for monitoring microenvironment changes.

Three novel polymerization routes have been successfully developed towards functional AIE polymers in Chapters II‒IV: (1) Pd-catalyzed multicomponent polymerizations of diynes, dibromoarenes and isonitriles for the synthesis of poly(proparagyl imine)s, (2) in situ generation of AIE-active poly(triphenylacrylonitrite)s from non-AIE active monomers of diynes, dibromoarenes and potassium ferrocyanide, (3) one-pot, three-component polymerizations of dihaloarenes, internal diynes and Grignard reagents for in situ generation of AIE-active poly(tetraphenylene)s. By physically doped into polymer films or forming crystalline film, environment sensitive AIEgens are utilized as fluorescent probes in three application scenarios in Chapter V-VII: (1) glass transition temperature of commercial polymers could be measured using grayscale by doping AIEgens into the polymer films, (2) relative humidity in different situations could be clearly visualized by assembling AIEgens with TICT properties into moisture-captured polymer network, (3) the first example of pure organic mechanoresponsive luminescent material for the real-time, full-field and on-site visualization of metal stress/strain distribution and fatigue crack propagation was achieved.