Spiro-Linked Ter-, Penta-, and Heptafluorenes as Novel Amorphous Materials for Blue Light Emission

• DOI: 10.1021/cm010679l
• Publication Date: 2002-07-26T04:50:07Z
• Authors: D. Katsis; Y. H. Geng; J. J. Ou; S. W. Culligan; A. Trajkovska; Shaw H. Chen; L. J. Rothberg
• Keywords: Quantum yield; Thermal Stability

A series of spiro-linked oligofluorenes were synthesized that exhibit blue emission with photoluminescence quantum yields in some cases exceeding 0.50 neat spin-coated films. Differential scanning calorimetry revealed highly variable glass transition temperatures. longer conjugation length is desired for better stability against thermally activated crystallization, and a shorter pendant higher temperature at given length. In contrast to poly(2,7-(9,9-di-n-octylfluorene)), prolonged heating spiro-oligo(fluorene) films resulted no changes morphology, emissive color, yield. The propensity spiro-oligo(fluorene)s crystallization was rationalized molecular shapes predicted by mechanics simulations.