Preparation, characterization, and solution tailored photoluminescence of all trans poly[distyrylbenzene-b-(ethylene oxide)]s Qunhui Sun a, * , Yulin Deng a , Junwu Chen b , Ben Zhong Tang b a School of Chemical and Biomolecular Engineering and IPST at GT, Georgia Institute of Technology, 500 10th St. NW, Atlanta, GA 30332-0620, USA b Department of Chemistry, Hong Kong University of Science and Technology, Hong Kong, China Received 16 July 2004; received in revised form 8 September 2004; accepted 20 September 2004 Available online 24 December 2004 Abstract Two linear, stereoregular, and structurally defined PPV derivatives (PPVs), poly[distyrylbenzene-b-(ethylene oxi- de)]s, with respective 12 and 16 of ethylene oxide repeat units in the backbone, abbreviated as DE-1 and DE-2 there- inafter, have been prepared via a modified synthetic profile. Both DE-1 and -2 were soluble in organic solvents and able to form robust and transparent film upon spin casting. Instrument characterization, such as FTIR, 1 H and 13 C NMR, UV–vis and fluorescence spectroscopy, revealed the final structures as designed and novel photophysical properties in solution. Apparent spectral evidences strongly suggested the all trans conjugated DE-1 and -2 and the successful iso- meirization process adopted. It was found that the aggregates were formed for both DE-1 and -2 at approximately 60% of methanol in methanol/dichloromethane (MeOH/DCM). Both DE-1 and -2 exhibited solution tailorable absorp- tion and emission properties. Before aggregating point, the absorption profile experienced a blue shift with the increase of MeOH and a slight increase in quantum yields (QYs). At aggregating point, however, an apparent blue shift in emis- sion profile was observed along with a remarkable decrease of QY due to aggregate quenching. Ó 2004 Elsevier Ltd. All rights reserved. Keywords: Stereoregular PPVs; Luminescence; trans-Configuration; Conjugated polymers; Blue shift 1. Introduction Conjugated polymers such as poly(p-phenylenevinyl- ene)s (PPVs) have attracted wide research interests in the last few decades due to their intriguing semiconducting and conducting properties upon doping [1], electro- and photoluminescence [2], and photovoltaic properties [3], etc. Among these, the electro- and photolumines- cence properties are of interest due to the applications in light-emitting diode [2], plastic lasers [4], thin film transistors [5], and other opto-electronic devices [6]. PPVs applications in solution state, apart from solid form, attracted great research interests [7] recently due to the development of polymer solution light-emit- ting device and gel light-emitting device by Yang and 0014-3057/$ - see front matter Ó 2004 Elsevier Ltd. All rights reserved. doi:10.1016/j.eurpolymj.2004.09.024 * Corresponding author. Tel.: +1 404 894 7824; fax: +1 404 894 4778. E-mail address: qunhui.sun@ipst.gatech.edu (Q. Sun). European Polymer Journal 41 (2005) 481–489 www.elsevier.com/locate/europolj EUROPEAN POLYMER JOURNAL