Conjugated copolymers bearing 2, 7-dithienylphenanthrene-9, 10-dialkoxy units: highly soluble and stable deep-blue emissive materials. (29th May 2020)

• Record Type: Journal Article
• Authors: Baig, Noorullah; Shetty, Suchetha; Fall, Sadiara; Al-Mousawi, Saleh; Heiser, Thomas; Alameddine, Bassam
• Is Part Of: New journal of chemistry. Volume 44:Number 22(2020)
• Page Start: 9557
• Page End: 9564
• Publication Date: 2020-05-29
• Subjects: Chemistry -- Periodicals; Chimie -- Périodiques; 540
• DOI: 10.1039/d0nj01712d
• Languages: English
• ISSNs: 1144-0546

Abstract

Abstract : Excellent yields, high stability and solubility. M w = 36.5–152.0 kDa and Đ = 2.5–3.0. Deep-blue emission with quantum yields up to 17%. Abstract : Conjugated copolymers PNP1–4 were prepared from the palladium catalyzed Suzuki–Miyaura cross-coupling reaction of 2, 7-dithienylphenanthrene units – bearing various alkoxy groups – PNM1–4 and 9, 9-dioctylfluorene-2, 7-diboronic acid FBA . The formation of copolymers PNP1–4 was confirmed by different analytical techniques, such as, gel permeation chromatography (GPC), thermogravimetry analysis (TGA), 1 H- and 13 C-nuclear magnetic resonance (NMR), Fourier transform infrared (FTIR), UV-vis absorption and emission spectroscopies. The target copolymers were found to have a relatively high thermal and chemical stability as well as an excellent solubility in common organic solvents. GPC traces of copolymers PNP1–4 display noticeably large weight-average ( M w ) molecular weights in the range of 36.5–152.0 kDa and a polydispersity index ( Đ = M w / M n ) of 2.5–3.0. Photophysical analysis of PNP1–4 divulges their luminescence in the deep blue region, namely, in the range of 453–463 nm with an emission quantum yield up to 17%. In addition, copolymers PNP1–4 were explored as field-effect transistors revealing a hole mobility up to ∼6.4 × 10 −6 cm 2 V −1 s −1 .