5 results found
Green JP, Cha H, Shahid M, et al., 2019, Dithieno[3,2-b:2,3-d]arsole-containing conjugated polymers in organic photovoltaic devices, Dalton Transactions, Vol: 48, Pages: 6676-6679, ISSN: 1477-9234
Arsole-derived conjugated polymers are a relatively new class of materials in the field of organic electronics. Herein, we report the synthesis of two new donor polymers containing fused dithieno[3,2-b:2′,3′-d]arsole units and report their application in bulk heterojunction solar cells for the first time. Devices based upon blends with PC71BM display high open circuit voltages around 0.9 V and demonstrate power conversion efficiencies around 4%.
Reichsöllner E, Creamer A, Cong S, et al., 2019, Fast and selective post-polymerization modification of conjugated polymers using dimethyldioxirane, Frontiers in Chemistry, Vol: 7, ISSN: 2296-2646
Modification of functional groups attached to conjugated polymer backbones can drastically alter the material properties. Oxidation of electron-donating thioalkyl substituents to electron-withdrawing sulfoxides or sulfones is a particularly effective modification. However, so far, this reaction has not been studied for the modification of conjugated polymers used in organic electronics. Crucial questions regarding selectivity and reaction time waited to be addressed. Here, we show that the reaction is highly selective and complete within just a few minutes when using dimethyldioxirane (DMDO) for the oxidation of thioalkyl substituents attached to the well-investigated conjugated polymers poly(9-(1-octylnonyl)carbazole-alt-4,7-dithienylbenzothiadiazole) (PCDTBT) and poly(9,9-dioctylfluorene-alt-benzothiadiazole) (F8BT). The selectivity was confirmed by comparison with polymers obtained from pre-oxidized monomers and by control experiments using related polymers without thioalkyl substituents. Using DMDO, the oxidation yields acetone as the only side-product, which reduces the work-up to mere evaporation of solvents and excessive reagent. Our results show that this oxidation is an exciting method for the preparation of electron-deficient conjugated polymers. It may even allow the preparation of electron acceptors for solar cells directly from the electron donors.
Heeney MJ, Creamer A, Wood C, et al., 2018, Post-polymerisation functionalisation of conjugated polymer backbones and its application in multi-functional emissive nanoparticles, Nature Communications, Vol: 9, ISSN: 2041-1723
Backbone functionalisation of conjugated polymers is crucial to their performance in many applications, from electronic displays to nanoparticle biosensors, yet there are limited approaches to introduce functionality. To address this challenge we have developed a method for the direct modification of the aromatic backbone of a conjugated polymer, post-polymerisation. This is achieved via a quantitative nucleophilic aromatic substitution (SNAr) reaction on a range of fluorinated electron deficient comonomers. The method allows for facile tuning of the physical and optoelectronic properties within a batch of consistent molecular weight and dispersity. It also enables the introduction of multiple different functional groups onto the polymer backbone in a controlled manner. To demonstrate the versatility of this reaction, we designed and synthesised a range of emissive poly(9,9-dioctylfluorene-alt-benzothiadiazole) (F8BT) based polymers for the creation of mono and multifunctional semiconducting polymer nanoparticles (SPNs) capable of two orthogonal bioconjugation reactions on the same surface.
Creamer A, Casey A, Marsh AV, et al., 2017, Systematic Tuning of 2,1,3-Benzothiadiazole Acceptor Strength by Monofunctionalization with Alkylamine, Thioalkyl, or Alkoxy Groups in Carbazole Donor-Acceptor Polymers, MACROMOLECULES, Vol: 50, Pages: 2736-2746, ISSN: 0024-9297
A simple route to the preparation of alkylamine, thioalkyl, and alkoxy monofunctionalized 4,7-di(thiophen-2-yl)-2,1,3-benzothiadiazole) based monomers is reported from a common fluorinated precursor. Copolymerization with a carbazole comonomer under Suzuki conditions yielded a series of analogous donor–acceptor copolymers in which the only difference was the nature of the heteroatom (N, O, or S) on the benzothiadiazole core. This was shown to have a significant impact on the wavelength and intensity of the intramolecular charge transfer (ICT) absorption peak due to a combination of electronic and steric factors. Substantial differences were also observed in the solar cell performance of blends with PC71BM, with the octylamino substituted polymer exhibiting significantly lower performance than the other two polymers. This polymer also exhibited a reversible change in the optical spectra upon exposure to acid, suggesting potential as a sensing material.
Marshall J, Hooton J, Han Y, et al., 2014, Polythiophenes with vinylene linked ortho, meta and para-carborane sidechains, POLYMER CHEMISTRY, Vol: 5, Pages: 6190-6199, ISSN: 1759-9954
This data is extracted from the Web of Science and reproduced under a licence from Thomson Reuters. You may not copy or re-distribute this data in whole or in part without the written consent of the Science business of Thomson Reuters.