Author(s)

Naofumi Naga^*, Nanae Tagaya, Haruhiko Tomoda

Department of Applied Chemistry, Materials Science Course, College of Engineering, Shibaura Institute of Technology, Tokyo, Japan.

Alternating copolymerization of 9,9-dihexyl-2,7-dibromofluorene, N-hexyl-2,7-dibromocarbazole (HCz) with diethynyldimethylsilane, diethynyldiphenylsilane, has been investigated using Sonogashira coupling reaction. Photophysical properties of the resulting copolymers were investigated with UV-Vis absorption and photoluminescence spectroscopy. All the copolymers in chloro-form solution showed absorption peaks at 270 - 280 nm with shoulder peaks at around 380 nm derived from π-π* transition or intra-molecular charge transfer through σ-π moiety, respectively. The chloroform solutions of the copolymers showed broad emission peaks at 415 - 425 nm. The emission wave lengths of the copolymers in the solid state (cast film) detected at 360 - 385 nm were remarkably blue-shifted in comparison with those in the chloroform solutions. Hydrosilylation reaction of the copolymers with 1,4-bis(dimethylsilyl)benzene yielded networked copolymers soluble in chloroform, indicating formation of branching polymers. The chloroform solutions of the HCz-based networked copolymers showed bimodal emission derived from new highly energy states in the σ-π conjugation.

Fluorene, Carbazole, Alternating Copolymer, Si-Ethynylene, Photophysical Property, Network Polymer

Naga, N. , Tagaya, N. and Tomoda, H. (2016) Synthesis and Photophysical Properties of Fluorene or Carbazole-Based Alternating Copolymers Containing Si and Ethynylene Units in the Main Chain. International Journal of Organic Chemistry, 6, 20-30. doi: 10.4236/ijoc.2016.61003.