Interchain Effects in Phenylene-Based Strapped Copolymers
Abstract
We discuss the absorption and emission properties of the phenylene-based polymers, poly(thienylene p-phenylene) (PT_pP) and poly(dithienylene p-phenylene) (PDT_pP), which incorporate straps to bridge the 2 and 5 positions of the phenyl ring. For PT_pP the absorption of solution and film forms both have a low lying maximum at 2.7 eV. The photoluminescence (PL) spectra are also very similar with a 0-0 transition at 2.3 eV and the 0-1 transition at 2.1 eV. For PDT_pP, we observe low energy absorption features at 2.8 eV and 3.2 eV with a maximum for the PL at 2.3 eV. In both samples, a dramatic reduction in the film quantum efficiency ( ~ 5% in PT_pP and < 1% in PDT_pP) is observed in comparison to that of the respective solutions ( ~ 80% and ~ 55%). The near identical absorption and PL for solution and film demonstrate that interchain emissive species such as excimers and aggregates are not present. The possible origin of the reduced PL efficiencies for the films will be discussed. We compare these results and photoinduced absorption studies to intra- and inter-chain phenomena in pyridyl vinylene-phenylene vinylene (PPyVPV) based copolymers which also incorporate straps.
- Publication:
-
APS March Meeting Abstracts
- Pub Date:
- March 1997
- Bibcode:
- 1997APS..MAR..M706J