Polynorbornene copolymers with pendent o-carborane and carbazole groups: Novel side-chain donor–acceptor copolymers for turn-on sensing of nucleophilic anions

• Published in: Polymer (Guilford) Vol. 54; no. 23; pp. 6321 - 6328
• Main Authors: Eo, Maengsun, Park, Myung Hwan, Kim, Taewon, Do, Youngkyu, Lee, Min Hyung
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.11.2013; Elsevier
• Subjects: anions; Applied sciences; Carbazole; composite polymers; Copolymer; electrochemistry; Exact sciences and technology; fluorescence; glass transition; o-Carborane; Organic polymers; Physicochemistry of polymers; Polymers with particular properties; Preparation, kinetics, thermodynamics, mechanism and catalysts; temperature; thermal stability; o-Carborane; Carbazole; Copolymer; Carborane copolymer; Norbornene derivative copolymer; Carbazole derivative copolymer; Fluorescence; Experimental study; Redox polymer; Complex catalyst copolymerization; Absorption spectrum; Thermal stability; Saturated copolymer; Organic solution; Electrochemical properties; Preparation
• ISSN: 0032-3861; 1873-2291
• DOI: 10.1016/j.polymer.2013.09.031

Vinyl-type polynorbornene copolymers with side-chain o-carborane (1-phenyl-o-carborane for P1–P3; 1-methyl-o-carborane for P4) and carbazole moieties were produced by vinyl addition copolymerization of norbornene monomers using a Pd(II) catalyst in combination with 1-octene chain transfer agent. The catalytic system provided well-defined copolymers with controlled incorporation of monomers. The copolymers possessed high thermal stability with high decomposition (Td5 > 410 °C) and glass transition temperatures (Tg > 350 °C). Treatment of the closo-copolymers (P1–P4) with excess KOH in refluxing EtOH/THF led to degradation of the closo-carborane cage to produce nido-copolymers (nido-(P1–P4)). While P1–P3 exhibited a weak carbazole-based fluorescence, the corresponding nido-copolymers gave rise to a 2.0–3.6-fold increase in PL intensity depending on the comonomer content. An electrochemical study and comparative PL results of P4 and nido-P4 suggest that photoinduced charge transfer from carbazole donors to 1-phenyl-o-carborane acceptors was responsible for the weak fluorescence of P1–P3. [Display omitted]