Enokida, Joshua S.; Tanna, Vijesh A.; Winter, H. Henning; Coughlin, E. Bryan
Progression of the Morphology in Random Ionomers Containing Bulky Ammonium Counterions
Poly(isoprene-ran-dimethyloctylammonium styrenesulfonate) (P(I-ran-DMOASS)) copolymers with high molecular weights and dimethyloctylammonium styrenesulfonate (DMOASS) compositions ranging between 8 and 40 mol % (30 and 77 wt %) were synthesized via nitroxide-mediated polymerization. Thermal and viscoelastic characterization revealed distinct behaviors for the low (30–51 wt %) and high (56–77 wt…
Conduction Band Fine Structure in Colloidal HgTe Quantum Dots
Hudson, Margaret H.; Chen, Menglu; Kamysbayev, Vladislav; Janke, Eric M.; Lan, Xinzheng; Allan, Guy; Delerue, Christophe; Lee, Byeongdu; Guyot-Sionnest, Philippe; Talapin, Dmitri V.
HgTe colloidal quantum dots (QDs) are of interest because quantum confinement of semimetallic bulk HgTe allows one to synthetically control the bandgap throughout the infrared. Here, we synthesize highly monodisperse HgTe QDs and tune their doping both chemically and electrochemically. The monodispersity of the QDs was evaluated using small-angle X-ray…
Effect of platelet size in a soft nanocomposite: Physical gelation and yielding
Tanna, Vijesh A.; Zhou, Yiliang; Henning Winter, H.
Journal of Rheology, 2018, vol 62, 3, pp. 791-800DOI:10.1122/1.5016535Visit the full articleBack to the overview
Studies on the 3-Lamellar Morphology of Miktoarm Terpolymers
Kim, Hyeyoung; Arras, Matthias M. L.; Mahalik, J. P.; Wang, Weiyu; Yu, Duk Man; Chernyy, Sergey; Goswami, Monojoy; Kumar, Rajeev; Sumpter, Bobby G.; Hong, Kunlun; Smith, Gregory S.; Russell, Thomas P.
The morphologies of ABC miktoarm star terpolymer consisting of polystyrene (PS), polyisoprene (PI), and poly(2-vinylpyridine) (P2VP) were studied by combining small-angle neutron and X-ray scattering (SANS and SAXS) and transmission electron microscopy. We find that this system displays a rich morphological behavior including an alternate lamellar (ALT.LAM), cylinder in undulated lamellar…
Highly Efficient Luminescent Liquid Crystal with Aggregation-Induced Energy Transfer
Liu, Yi; You, Li Hong; Lin, Fa Xu; Fu, Kuo; Yuan, Wang Zhang; Chen, Er-Qiang; Yu, Zhen-Qiang; Tang, Ben Zhong
A luminescent liquid crystal molecule (TPEMes) with efficient solid-state emission is rationally constructed via the chemical conjugation of blue-emitting tetraphenylethene cores and luminescent mesogenic tolane moieties, which are both featured with aggregation-induced emission properties. As for this fluorophore, aggregation-induced energy transfer from the emissive tolane mesogens to the…
Quantitative Analysis of Semiconductor Nanocrystal Ensemble Optical Extinction
Staller, Corey M.; Agrawal, Ankit; Gibbs, Stephen L.; Cabezas, Camila A. Saez; Johns, Robert W.; Milliron, Delia J.
The optical extinction coefficients of localized surface plasmon resonance (LSPR) in doped semiconductor nanocrystals (NCs) have intensities determined by the free charge carrier concentration and the mechanisms for damping the oscillation of those free carriers. We investigate the dependence of the extinction coefficient of tin-doped indium oxide (ITO) NCs on…
Aqueous Polysulfide–Air Battery with a Mediator-Ion Solid Electrolyte and a Copper Sulfide Catalyst for Polysulfide Redox
Gross, Martha M.; Manthiram, Arumugam
Aqueous sodium polysulfide–air batteries are a promising system for enabling low-cost, high energy density, environmentally benign batteries for grid-scale deployment. However, the sluggish redox kinetics of aqueous polysulfide requires the use of a catalyst. Cobalt sulfide is a traditional catalyst with good activity and stability, but it uses expensive and…
Rapid and Quantitative De-tert-butylation for Poly(acrylic acid) Block Copolymers and Influence on Relaxation of Thermoassociated Transient Networks
Filippov, Alexei D.; van Hees, Ilse A.; Fokkink, Remco; Voets, Ilja K.; Kamperman, Marleen
The synthesis of charged polymers often requires the polymerization of protected monomers, followed by a polymer-analogous reaction to the polyelectrolyte product. We present a mild, facile method to cleave tert-butyl groups from poly(tert-butyl acrylate) blocks that yields poly(acrylic acid) (pAA) blocks free of traces of the ester. The reaction utilizes…
Guided Assembly of Block Copolymers in Three-Dimensional Woodpile Scaffolds
Choi, Jaewon; Koo, Sangmo; Sakellari, Ioanna; Kim, Hyeyoung; Su, Zhengliang; Carter, Kenneth R.; Farsari, Maria; Grigoropoulos, Costas P.; Russell, Thomas P.
Three-dimensional (3D) nanofabrication using the directed self-assembly of block copolymers (BCPs) holds great promise for the nanoscale device fabrication and integration into 3D architectures over large areas with high element densities. In this work, a robust platform is developed for building 3D BCP architectures with tailored functionality using 3D micron-scale…
Size-Selective Adsorption in Nanoporous Polymers from Coumarin Photo-Cross-Linked Columnar Liquid Crystals
Concellón, Alberto; Schenning, Albertus P. H. J.; Romero, Pilar; Marcos, Mercedes; Serrano, José Luis
We have prepared nanoporous polymers from columnar hexagonal hydrogen-bonded complexes, whose order is fixed by coumarin photoinduced cycloaddition (photodimerization). Two different hydrogen-bonded complexes were used and consisted of a melamine (M) or tris(triazolyl)triazine (T) derivative acting as central templates and three peripheral carboxylic acids containing coumarin units. These…