Películas fluorescentes azules basadas en derivados de poli-2,7-fluorenofenilideno

Abstract

La cuaternización del poli-(9,9-bis(6'-bromohexilo)fluorenofenileno) por tratamiento de trimetilamina gaseosa se emplea para obtener una sal de amonio del copolímero precursor soluble en agua. El copolímero neutro contiene unidades alternantes repetitivas de fluoreno/ fenilideno obtenidas mediante una acoplamiento de Suzuki con Pd (II). Los polímeros se caracterizaron por cromatografía de permeación (GPC), espectroscopia RMN de 1 H y 13 C , espectroscopia IR transformada de Fourier y análisis termogravimétrico (ATG). El polímero neutro mantiene la estabilidad hasta los 300ºC, mientras el derivado catiónico comienza a descomponer a 120ºC, con una progresiva perdida de masa hasta los 290ºC. Las propiedades ópticas de los polímeros se estudiaron en disolución y en películas mediante espectroscopias UV/VIS y de fluorescencia. Las películas delgadas de sílice mesoporosa se prepararon como materiales receptores de los copolímeros fluorescentes. Palabras clave: Polímeros conjugados, solubles en agua, Pd(II), sílice mesoporosa.Blue fluorescent films based on poly-2,7-fluorene-phenylene derivatives.Quaternization of poly-(9,9-bis(6'-bromohexyl)fluorenephenylene by treatment with trimethylamine gas was used to obtain a water soluble ammonium salt copolymer. The neutral copolymer containing fluorene/phenylene alternating repeating units was obtained by a palladiumcatalyzed Suzuki coupling reaction. This strategy could be applied to prepare water soluble conjugated polymers with the ability to change the charge functionality. The polymers were characterized by gel permeation chromatography (GPC), 1 H and 13 C NMR spectroscopy, FT-IR spectroscopy, and thermogravimetric analysis (TGA). The neutral polymer was stable to over 300ºC, while the cationic polymer begins to degrade at 120ºC with a progressive loss of mass at 290ºC. The optical properties of the polymers were investigated in solution and solid phases by UV/VIS and fluorescent spectroscopy. Mesoporous silica thin films were prepared as a host matrix for the fluorescent copolymers.

Interaction between Poly(9,9-bis(6′-N,N,N-trimethylammonium)hexyl)fluorene phenylene) Bromide and DNA as Seen by Spectroscopy, Viscosity, and Conductivity: Effect of Molecular Weights and DNA Secondary Structure

“…17 We assume, in agreement with previous reports, 18 that almost quantitative conversion of the neutral copolymer into the cationic one (HTMA-PFP) occurred, and that did not affect the degree of polymerization.…”

Advantageous Microwave-Assisted Suzuki Polycondensation for the Synthesis of Aniline-Fluorene Alternate Copolymers as Molecular Model with Solvent Sensing Properties

“…Quaternization of PAFBr was successfully obtained with total conversion (>97%) and a high purification yield (80%) of the new polyelectrolyte ( PAFAm ), using the treatment with trimethylamine, as previously reported [53,54]. Nucleophilic substitution was corroborated by proton and bi-dimensional HMQC NMR in DMSO-d 6 .…”

“…Poly{1,4-(2/3-aminobenzene)-co-alt-2,7-[9,9´-bis(6’’-N,N,N-trimethylammoniumhexyl)fluorene]} dibromide ( PAFAm ). Quaternization of PAFBr by treatment with trimethylammine, following previous reported studies in our lab, yield 80% [54].…”

Synthesis and Characterization of a Novel Green Cationic Polyfluorene and Its Potential Use as a Fluorescent Membrane Probe

“…P1 was synthesized from the monomers M1 and M2 by a Suzuki cross-coupling reaction carried out in a microwave reactor. Microwave-assisted synthesis allowed us to significantly reduce the reaction time compared to other analogous polymers previously synthesized by our research group from 48 h to only 22 min [28,30,42]. For the synthesis of P1 , the method known as Solid Phase Synthesis (SPS) was used, because it provides the best results in the synthesis of CPs in microwaves, as indicated in previous references [19,43] As a final product, a solid with yellow-green colour was obtained with a yield of 59%.…”

“…Bluish emission is common in fluorene-based CPEs, while copolymerization with other aromatic units change to longer wavelengths [23,24,25,26,27]. In this respect, our group has synthesized blue- and red-emitter cationic polyfluorenes, copoly-{(9,9-bis(6′- N , N , N -trimethylammonium)hexyl]-2,7-(fluorene)- alt -1,4-(phenylene)} bromide (HTMA-PFP) and copoly-{[9,9-bis(6′- N , N , N -trimethylammonium)hexyl]-2,7-(fluorene)- alt -1,4-(naphtho[2,3c]-1,2,5-thiadiazole)} bromide (HTMA-PFNT), which incorporate a phenyl and a naphtha[2,3c][1,2,5]thiadiazole group on fluorene backbone, respectively [28,29,30,31]. Both blue and red polyfluorenes have been characterized in aqueous media along with in the presence of biological systems.…”