Confinement Effects on the Optical Properties and Chain Conformations of Poly(9,9‐di‐<i>n</i>‐octylfluorene‐<i>alt</i>‐benzothiadiazole) Nanotubes

Chu, Chien Wei; Jeng, Kai Sheng; Huan, Mu; Tsai, Chia Chan; Cheng, Ming; Chen, Jiun‐Tai

doi:10.1002/macp.201600178

Cited by 8 publications

(6 citation statements)

References 44 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Various methods have been reported over the past decades for the preparation of orientated films. For instance, rubbing, − friction transfer, − and strain alignment − are useful methods that are based on facile drying processes. Soft friction transfer has been recently developed by combining a dry process with a wet process .…”

Section: Introductionmentioning

confidence: 99%

Brush Printing Creates Polarized Green Fluorescence: 3D Orientation Mapping and Stochastic Analysis of Conductive Polymer Films

Sakata

Kajiya

Saitow

2020

ACS Appl. Mater. Interfaces

View full text Add to dashboard Cite

Brush printing is a unique method used to obtain uniaxially oriented films, whereby a polymer solution is brushed onto a substrate. However, there have been only a few reports on the brushprinting method. Here, we report the preparation of a uniaxially oriented film of a green light-emitting conductive polymer, poly(9,9dioctylfluorene-alt-benzothiadiazole) (F8BT). The fluorescence polarization ratio of the oriented F8BT films was as high as 11.3, and the average orientation factor reached 0.74 ± 0.06. The orientation factor and the torsion angle of F8BT were visualized by two mappings of fluorescence and Raman spectral measurements by confocal spectromicroscopy, respectively. These two x-y mapping data with many pixels (∼750 pixels) were evaluated by x-y-z mapping of the film thickness at a single position and were used to reveal the threedimensional (3D) orientation mechanism from a stochastic approach. Polarized green fluorescence originates from polymer chains uniaxially oriented along the brush direction. The high orientation for a film thickness < 100 nm is established by shear stress, faster capillary flow, and flow-induced chain extension for a thin solution film on a substrate. The high orientation factor was also demonstrated by a high brushing speed, whereas an optimized brushing speed existed. We found that this optimization is attributed to the property of a non-Newtonian fluid. By applying this brush-printing method to the fabrication of an optoelectrical device, polarized green electroluminescence was preliminarily demonstrated by the OLED assembled from an oriented F8BT film.

show abstract

Section: Introductionmentioning

confidence: 99%

Brush Printing Creates Polarized Green Fluorescence: 3D Orientation Mapping and Stochastic Analysis of Conductive Polymer Films

Sakata

Kajiya

Saitow

2020

ACS Appl. Mater. Interfaces

View full text Add to dashboard Cite

show abstract

“…Two main peaks at 1546 and 1610 cm −1 were attributed to the polymer backbone (ring stretching modes for the BT and fluorene, respectively) (Figure S19, Supporting Information). [ 16 ] Compared with 633 nm light, the 785 and 830 nm light were far from the absorption edge of F8BT NP. When these two lights were used, the intensity of the Raman signals significantly decreased.…”

Section: Resultsmentioning

confidence: 99%

Molecular Regulation of Polymeric Raman Probes for Ultrasensitive Microtumor Diagnosis and Noninvasive Microvessle Imaging

Cui

Zhang

Chen

et al. 2022

Small

View full text Add to dashboard Cite

method, including Raman and fluorescence, has attracted great attention in in vivo imaging due to their superior spatial resolution and sensitivity. [3] Especially, Raman imaging is a powerful vibrational optical spectroscopic technique and provides specific fingerprint information for a wide range of target molecules with ultranarrow spectral widths. These endowed Raman technology with advantage in imaging substances with overlapping fluorescence spectra and imaging in complex biological environments. Raman imaging is also highlighted with outstanding ability to tackle photobleaching and photodegradation, and thus suitable for long-term imaging. [2d,4] Raman imaging has shown great potential in diagnosis of cancers and visualization of various biological processes. To our knowledge, Raman probes for in vivo imaging are limited to surface enhanced Raman spectroscopy (SERS) probes (Au, Ag, and Cu nanoparticles), vibrational probes (alkyne, nitrile, and C-D) and single-walled carbon nanotube (SWNT) resonance Raman probes. [4a,5] Polymers, as materials with excellent biocompatibility, are expected to be a new generation of probes for in vivo Raman imaging. However, very few polymers have been reported to date as probes for high-sensitive in vivo Raman imaging, presumably because of the following reasons: i) the Raman signals of the developed polymers are intrinsically weak; and ii) the generated strong fluorescence background under excitation will interfere with the Raman signals. [6] To overcome these shortcomings, polymers were doped with other substances to increase the Raman signal intensity and reduce fluorescence. For example, polymers were coated on the surface of Au nanoparticles to enhance their Raman signals, based on the SERS effects. [6a] Other studies doped polymers with polydopamine to quench fluorescence and improve Raman signal intensity of polymers through an intermolecular energy transfer process. [6b] Nevertheless, the doping approach merely provided limited Raman signal enhancement for polymers, and these doped polymeric probes still failed to achieve high-resolution and sensitive in vivo imaging. Taken together, exploration of polymers as Raman imaging is a powerful tool for the diagnosis of cancers and visualization of various biological processes. Polymers possessing excellent biocompatibility are promising probes for Raman imaging. However, few polymers are reported to serve as Raman probes for in vivo imaging, mainly due to the intrinsic weak Raman signal intensity and fluorescence interference of these polymers. Herein, a poly(indacenodithiophene-benzothiadiazole) (IDT-BT) polymer is presented, which emits unprecedentedly strong Raman signals under the near-infrared wavelength (785 nm) excitation, thus functioning as a Raman probe for ultrasensitive in vivo Raman imaging. Further mechanistic studies unveil that the unique Raman feature of the IDT-BT polymer relies on molecularly regulating its absorbance edge adjacent to the desired excitation wavelength, thus avoiding fluorescence i...

show abstract

“…It has been studied that the conformations and chain packings of polymer nanomaterials prepared by the template wetting methods can vary under different confined environments . Therefore, in this work, the P3HT nanowires are prepared by the solution wetting method and the SAINT method.…”

Section: Resultsmentioning

confidence: 99%

“…It has been studied that the properties such as glass transition temperatures, optical properties, and crystallinities of polymer nanostructures under different confined conditions or fabricated using various preparation methods may vary because of different chain conformations . For instance, Martin et al studied the packing behaviors of P3HT chains confined in the nanopores of AAO templates for samples prepared by the solution wetting method and the melt wetting method via X‐ray investigations .…”

Section: Introductionmentioning

confidence: 99%

Orientation Preferences of Interchain Stackings for Poly(3‐hexylthiophene) Nanowires Prepared Using Template‐Based Wetting Methods

Jeng

Chu

Liu

et al. 2018

Macro Chemistry & Physics

Self Cite

View full text Add to dashboard Cite

Poly(3‐hexylthiophene) (P3HT) nanowires have drawn great attention recently because of their unique properties that can be applied to optoelectronic devices such as conjugated polymer solar cells and organic field‐effect transistors. There is still an urgent need, however, to study the fabrication and characterization of P3HT nanowires with controllable morphologies and molecular orientations. In this work, feasible routes are presented to fabricate P3HT nanowires using the solution wetting template method and the solvent‐annealing‐induced nanowetting in template (SAINT) method. The morphologies and chemical compositions of the P3HT nanowires prepared using these two methods are confirmed by scanning electron microscopy, transmission electron microscopy (TEM), and Raman spectroscopy. From the ultraviolet‐visible spectroscopy and wide‐angle X‐ray scattering results, it is concluded that the degrees of the crystallinity and the orientation preferences of interchain stackings along the pore axis for the P3HT nanowires prepared by the SAINT method are higher than those prepared by the solution wetting template method.

show abstract

Confinement Effects on the Optical Properties and Chain Conformations of Poly(9,9‐di‐n‐octylfluorene‐alt‐benzothiadiazole) Nanotubes

Cited by 8 publications

References 44 publications

Brush Printing Creates Polarized Green Fluorescence: 3D Orientation Mapping and Stochastic Analysis of Conductive Polymer Films

Brush Printing Creates Polarized Green Fluorescence: 3D Orientation Mapping and Stochastic Analysis of Conductive Polymer Films

Molecular Regulation of Polymeric Raman Probes for Ultrasensitive Microtumor Diagnosis and Noninvasive Microvessle Imaging

Orientation Preferences of Interchain Stackings for Poly(3‐hexylthiophene) Nanowires Prepared Using Template‐Based Wetting Methods

Contact Info

Product

Resources

About