Syntheses and Characterization of the Alternating Polymers Based on Cyclopenta[def]phenanthrene Backbone with Spiro Group

Abstract

New electroluminescent spiro-PCPP copolymers, poly((2,6-(3',6'-bis(2-ethylhexyloxy)-spiro(4H-cyclopenta[def]phenanthrene-4,9'-[9H]fluorene)))-alt-(2 6-(4,4-bis(2-ethylhexyl)-4H-cyclopenta[def]phenanthrene))) (spiro-PCPP-alt-PCPP) and poly((2,6-(3',6'-bis(2-ethylhexyloxy)-spiro(4H-cyclopenta[def]phenanthrene-4,9'-[9H]fluorene)))-alt-(1,4-phenylene)) (spiro-PCPPP), have been synthesized by the Suzuki-Miyaura polymerization. Both of the PL emission spectra of the polymers in chloroform show the maximum peaks at 397 nm. The maximum peaks of the PL emission spectra of the polymers in solid thin films appeared at around 448 and 441 run which are red-shifted over 40 nm as compared to those of the solution conditions, which is caused by the increased inter-chain interaction in solid state. Both of the EL spectra of the sprio-PCPP copolymers exhibited maximum peaks at 448 nm.