Photophysical analysis of dual fluorescence and phosphorescence emissions observed for semi-aliphatic polyimides at lower temperatures

• DOI: 10.1039/d4cp00538d
• Publication Date: 2024-05-07T10:00:35Z
• Authors: Mayuko Nara; Eisuke Fujiwara; Aurimas Vyšniauskas; Vidmantas Gulbinas; Shinji Ando
• Keywords: Intersystem crossing; Alicyclic compound

The photoluminescence (PL) properties of four types blue fluorescent semi-aliphatic polyimides (PIs) derived from aromatic dianhydrides (ODPA, BPDA, HQDEA, and BPADA) an alicyclic diamine (DCHM) were investigated at temperatures ranging room temperature (RT, 298 K) to 30 K analyse the origins their non-radiative relaxation (NR) processes. These PIs exhibited significant increases in fluorescence (FL) intensity lifetimes when lowering temperature, stabilising below 100 K. containing ether (-O-) linkages showed a shoulder peak around 500 nm 150 K, which is attributable phosphorescence (PH). results show that NR deactivation RT includes three processes: intersystem crossing (ISC) excited singlet (S