Phenomenon of aggregation-induced emission(AIE)

discovered in 2001

has been developed rapidly from early small molecules to polymer systems. Compared with traditional small molecules

polymer materials with AIE property can overcome the problems on processing and create favorable conditions for the preparation of highly efficient light-emitting devices. AIE mechanisms with the unchanged core of radiative transition channels caused by aggregation are developing with the discovery of AIE systems. The formation of each AIE phenomenon often requires the synergy of several factors. Continuous improvement of the mechanism on one hand help to explain the AIE phenomenon

on the other hand lay the theoretical foundation for the development of a new AIE system. This paper summarizes several polymer AIE systems which are formed on the basis of small molecules and introduces some relatively new AIE mechanisms based on the existing ones.