Photoluminescence, poly aggregates

The introduction of bulky side chains that contain adamantyl groups to poly(p-phenylenevinylene) (PPV), a semiconducting conjugated polymer, decreases the number of interchain interactions. This action will reduce the aggregation quenching and polymer photoluminescence properties would be improved [93]. 

Beyond cyano-OPVs, several other dyes that form excimers in their aggregated state have also been used for mechanosensing purposes. Pucci and coworkers have reported that poly(propylene) (PP) films containing bis(benzoxazolyl)stilbene (BBS) (Fig. 9a) change photoluminescence color upon tensile deformation [50]. In the as-prepared state, the emission spectrum (Fig. 9b) shows a broad excimer emission band around 500 nm, along with sharper monomer emission bands at 410, 430, and 455 nm. Mechanical deformation lowers the intensity of the excimer band, resulting in a photoluminescence color change (Fig. 9c). 

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