In the current polymer system, only weak-to-moderate charge transfer (e.g., from styrene, 2VN, and FluoMA donor groups) is considered effective to achieve strong PDI aggregate emission with high PLQY, owing to the potential distortion of PDI stacking. When designing highly emissive red-color PDI polymers, such a trade-off in selection of a suitable charge transfer donor must be evaluated. Despite the low PLQY of pyrene-and anthracene-based PDI polymers, their NIR emission makes them potentially useful for specific applications such as bioimaging and fluorescence sensing.