A5004661287- Carbon Nanotubes in Composites
- Conducting polymers and applications
- Synthesis and properties of polymers
- Organic Electronics and Photovoltaics
- Surface Modification and Superhydrophobicity
- Semiconductor Lasers and Optical Devices
- Advanced Polymer Synthesis and Characterization
- Photonic and Optical Devices
- Silicone and Siloxane Chemistry
- Nanopore and Nanochannel Transport Studies
- Surfactants and Colloidal Systems
- Block Copolymer Self-Assembly
- Advanced Sensor and Energy Harvesting Materials
- Polymer Surface Interaction Studies
- Fullerene Chemistry and Applications
- Fluid Dynamics and Heat Transfer
- Adhesion, Friction, and Surface Interactions
- Advanced Fiber Optic Sensors
- Organic Light-Emitting Diodes Research
- Analytical Chemistry and Sensors
- Luminescence and Fluorescent Materials
- Graphene research and applications
- Mechanical and Optical Resonators
- Fuel Cells and Related Materials
- Perovskite Materials and Applications
National Research Council Canada
2016-2025
National Academies of Sciences, Engineering, and Medicine
2005-2015
Simon Fraser University
2012
Universitat Politècnica de València
2010
Nanjing University of Posts and Telecommunications
2010
Instituto de Tecnología Química
2010
Institute for Microstructural Sciences
2005-2009
Communications Research Centre Canada
2005-2008
Institute for Biological Sciences
2007
University of Calgary
1996-1999
Four aluminum surfaces with wettability varied from superhydrophilic to superhydrophobic were prepared by combining an etching and a coating process. The surface was checked in terms of water contact angle (CA) sliding (SA) under different humidity at -10 °C. High-speed photography applied study droplet impact dynamics on these surfaces. It found that single successive droplets could rebound the roll off tilt larger than 30° extremely condensing weather condition (-10 °C relative 85-90%). In...
A simple and low-cost technique for the preparation of silicon-oil-infused polydimethylsiloxane (PDMS) coatings with different silicon oil contents have been developed studied. This material is designed ice-phobic applications, thus a high hydrophobic property PDMS maintained by avoiding any polar groups such as C═O OH in structure. Therefore, polymer main chain was attached vinyl Si–H to obtain cross-linking capability, meanwhile ensure nonpolar chemical Its has investigated terms ice...
Abstract A new class of comb‐shaped polymers for use as a proton conducting membrane is presented. The polymer designed to combine the beneficial physical, chemical, and structural attributes fluorinated Nafion‐like materials with higher‐temperature, polyaromatic‐based backbones. unites rigid, polyaromatic, hydrophobic backbone lengthy hydrophilic side chains; this combination affords direct control over nanostructure within results in distinct microphase separation between opposing domains....
A systematic study on the use of 9,9-dialkylfluorene homopolymers (PFs) for large-diameter semiconducting (sc-) single-walled carbon nanotube (SWCNT) enrichment is focus this report. The based a simple three-step extraction process: (1) dispersion as-produced SWCNTs in PF solution; (2) centrifugation at low speed to separate enriched sc-tubes; (3) filtration collect sc-SWCNTs and remove excess polymer. effect conditions purity yield including molecular weight alkyl side-chain length...
Abstract A series of alternating copolymers cyclopenta[2,1‐b;3,4‐b′]dithiophene (CPDT) and thieno[3,4‐c]pyrrole‐4,6‐dione (TPD) have been prepared characterized for polymer solar cell (PSC) applications. Different alkyl side chains, including butyl (Bu), hexyl (He), octyl (Oc), 2‐ethylhexyl (EH), are introduced to the TPD unit in order adjust packing chain solid state, while on CPDT remains unchanged simplify discussion. The polymers this a simple main structure can be synthesized easily,...
ConspectusSemiconducting single-walled carbon nanotubes (sc-SWCNTs) are emerging as a promising material for high-performance, high-density devices well low-cost, large-area macroelectronics produced via additive manufacturing methods such roll-to-roll printing. Proof-of-concept demonstrations have indicated the potential of sc-SWCNTs digital electronics, radiofrequency circuits, radiation hard memory, improved sensors, and flexible, stretchable, conformable electronics. Advances toward...
A polyisoprene-block-poly(2-cinnamoylethyl methacrylate) (PI-b-PCEMA) sample with 88 units of isoprene and 2.3 × 102 CEMA formed vesicles in THF/hexanes hexanes volume fractions between 50% 95%. The had PCEMA as the shell PI chains stretching into solution phase from both inner outer surfaces shell. cavity diameter is ∼38 nm, fraction there low. After was cross-linked, were converted to water-soluble poly(2,3-dihydroxyl-2-methyl-butane) chains. hollow nanospheres uptook a large amount...
Alternating copolymers of 9,9-dioctylfluorene and oxadiazole have been prepared by the tetrazole route or Suzuki coupling reaction. In polymers units were evenly dispersed in main chain at every one, P(F1-alt-Ox), three, P(F3-alt-Ox), four, P(F4-alt-Ox), fluorene units. Another copolymer with an asymmetric repeat unit structure, P(F3−Ox−F1−Ox) has also for comparison. this study, demonstrated to offer several advantages preparing polyoxadiazole well-defined structures compared other ring...
Polystyrene-block-poly(2-cinnamoylethyl methacrylate), PS-b-PCEMA, forms spherical micelles with PCEMA corona and PS core in THF/acetonitrile 10%, by volume, of THF. Nanospheres cross-linked shells are obtained photolyzing the sample UV light. Despite corona, degree intermicellar fusion is low at CEMA conversions less than ∼40%. The nanospheres, greater ∼10% conversions, dispersible structurally stable THF or toluene which solubilizes both un-cross-linked PCEMA.
Abstract Four monodisperse starburst oligomers bearing a 4,4′,4″‐tris(carbazol‐9‐yl)‐triphenylamine (TCTA) core and six oligofluorene arms are synthesized characterized. The lengths of vary from one to four fluorene units, giving the molecular weights ranging 3072 10 068 Da (1 = 1.66 × –27 kg). All have good film‐forming capabilities, display bright, deep‐blue fluorescence (λ max 395–416 nm) both in solution solid state, with quantum efficiencies films (Φ PL ) varying between 27 88 %....
Abstract A limitless‐length flexible active‐matrix implies that virtually any surface can be rendered into an interactive medium when laminated with electrophoretic or organic light‐emitting diode sheets. However, performance, cost, and size limitations of current fabrication technologies semiconducting materials, typically utilized in thin film transistor (TFT) active matrices (TFT‐AMs), have hindered progress, thus preventing the realization fully printed TFT‐AMs on a plastic roll. new...
Conjugated polymer extraction (CPE) has been shown to be a highly effective method isolate high-purity semiconducting single-walled carbon nanotubes (sc-SWCNTs). In both literature reports and industrial manufacturing, this enabled enrichment of sc-SWCNTs with high purity (≥99.9%). High selectivity is typically obtained in nonpolar aromatic solvents, yet polar solvents may provide process improvements terms yield, efficiency. Using an amphiphilic fluorene-alt-pyridine conjugated copolymer...
A poly(tert-butyl acrylate)-block-poly(2-cinnamoylethyl methacrylate), PtBA-b-PCEMA, sample was synthesized and characterized. After annealing at 105 ± 2 °C, the PtBA block formed densely packed cylinders inside PCEMA matrix. Thin films of diblock were obtained by microtomy. photo-cross-linking, tert-butyl groups hydrolyzed, leaving poly(acrylic acid) chains in loosely nanometer-sized cylinders. The permeability water across such varied several orders magnitude, depending on pH aqueous...
A polyisoprene-block-poly(2-cinnamoylethyl methacrylate) (PI-b-PCEMA) sample formed vesicles in THF/hexanes with a THF volume fraction of 20%. In such vesicles, PCEMA made up the essentially-solvent-free spherical shell and PI chains stretched into solution phase from both inner outer surfaces. Hairy hollow nanospheres were prepared by photo-cross-linking shell. Treating cross-linked ozone for short period selectively degraded to yield semi-shaved nanospheres. Fully shaved degrading using...
A novel purification process for the enrichment of sc-SWCNTs that combines selective conjugated polymer extraction (CPE) with adsorption using silica gel, termed hybrid-CPE (h-CPE), has been developed, providing a high purity sc-SWCNT material significant improvement in efficiency and yield. Using h-CPE protocol, greater than 5 fold yield can be obtained compared to traditional CPE while obtaining >99.9% as assessed by absorption spectroscopy Raman mapping. Thin film transistor devices...
High-purity semiconducting single-walled carbon nanotubes (sc-SWCNTs) are promising for portable and high-sensitivity gas sensors because of their excellent physical electrical properties. Here, we describe the synthesis a novel indigo-fluorene-based copolymer (PFIDBoc) that has been designed to selectively enrich sc-SWCNTs with purity (>99.9%) yet contain latent function in form tert-butoxy (t-BOC)-protected amine can be later revealed exploited dioxide (CO2) sensing. SWCNTs wrapped PFIDBoc...
Novel cross-linkable, highly fluorinated poly(arylene ether ketones/sulfones) have been prepared by copolycondensation reactions of perfluorinated aromatic ketone/sulfone with 4,4'-(hexafluoroisopropylidene)diphenol and a tetrafluorostyrol-containing bisphenol (i.e., 1,1-bis(4-hydroxyphenyl)ethyl-1-phenyl 2,3,5,6-tetrafluorostyrol ether). The were conducted at low temperature in the presence calcium hydride cesium fluoride. resulting polymers number-average molecular weights range 25 000−36...
Novel molecularly imprinted polymeric nanospheres (MIPNs) were prepared combining both molecular imprinting and block copolymer self-assembly techniques. A diblock copolymer, poly[(tert-butyl methacrylate)-block-(2-hydroxylethyl methacrylate)] (PtBMA-b-PHEMA), was synthesized by living free radical polymerization. Further postfunctionalization introduced 2-acrylamido-6-carboxylbutylamidopyridine (ACAP) cross-linkable methacryloyl side groups into the polymer. The resulting final able to...
The icephobic properties (both in ice-adhesion reduction and water rebound) of different superhydrophobic surfaces varied wildly at sub-zero condensate environment.