Pickford, Tom; Gu, Xu; L. Heeley, Ellen; Wan, Chaoying
Effects of an ionic liquid and processing conditions on the ?-polymorph crystal formation in poly(vinylidene fluoride)
The piezoelectric properties of poly?vinylidene fluoride) (PVDF) are determined by the prevalence and orientation of its polar ?-crystal phase, which can be tuned by processing conditions, additives, mechanical stretching or post-treatment. Here, the effects of three types of processing conditions on the crystalline structure evolution of PVDF were investigated; electrospinning,…
Supramolecular luminescent triblock copolymer thermoplastic elastomer via metal-ligand coordination
Jiang, Feng; Zhang, Xin; Hwang, Wonseok; Briber, Robert M.; Fang, Yanxiong; Wang, Howard
We have performed synthesis and testing of novel supramolecular thermoplastic elastomers (TPEs). The polymers incorporate metal-ligand bonds between terbium (Tb3+) ions and imidazole groups in a triblock copolymer poly(isobornyl acrylate)-block-poly(n-butyl acrylate-co-1-vinylimidazole)-block-poly(isobornyl acrylate) (PIBA-b-P(BA-co-VI)-b-PIBA) as a second reversible physical cross-link in
Synthesis and Solid-State Properties of PolyC3 (Co)polymers Containing (CH2CH2C(COOR)2) Repeat Units with Densely Packed Fluorocarbon Lateral Chains
Illy, Nicolas; Urayeneza, Deogratias; Maryasevskaya, Alina V.; Michely, Laurent; Boileau, Sylvie; Brissault, Blandine; Bersenev, Egor A.; Anokhin, Denis V.; Ivanov, Dimitri A.; Penelle, Jacques
The synthesis and structural characterization of linear PolyC3 polymers containing trimethylene-1,1-dicarboxylate structural repeat units with C6F13 and C8F17 fluorinated side chains is described for the first time, and their properties were compared with the traditional polyvinyl structures that display the fluorinated chain on every second rather than on every third…
TiO2-carbon nanoporous composites prepared via ZnO nanoparticle-templated carbonization of glucose adsorb and photodegrade organic pollutants in water
Barrera, Luis A.; Escobosa, Alma C.; Nevarez, Aileen; Dominguez, Noemi; Bañuelos, Jose L.; Westerhoff, Paul; Noveron, Juan C.
We report the ZnO nanoparticle-templated formation of nanoporous carbon (NTC) embedded with TiO2 nanoparticles for the adsorption and photodegradation of organic pollutants in water. Small-angle X-ray scattering (SAXS) studies indicate that NTC and NTC-TiO2 exhibit two types of porosities with average pore diameters of 2.8 and 11.5?nm, while Brunauer-Emmet-Teller (BET)…
Ballistic thermal phonons traversing nanocrystalline domains in oriented polyethylene
Robbins, Andrew B.; Drakopoulos, Stavros X.; Martin-Fabiani, Ignacio; Ronca, Sara; Minnich, Austin J.
Polymer crystals that are good conductors of heat are highly desirable for thermal management applications. Although thermally conductive polymer crystals are well known, the microscopic thermal transport processes that enable these properties have been challenging to probe experimentally. We used an optical method to probe heat conduction at submicrometer length…
Improvement in mechanical and structural properties of poly(ethylene terephthalate) nanohybrid
Saxena, Dipti; Rana, Dipak; Bhoje Gowd, E.; Maiti, Pralay
The wide range of applicability of poly(ethylene terephthalate) (PET) in various fields such as packaging, automobile parts, sports and textile due to its transparent nature, light weight and mechanical properties creates strong case to enhance its mechanical properties. By embedding nanofillers and thereby improving the mechanical properties, this spectrum can…
4D biofabrication of skeletal muscle microtissues
Apsite, Indra; Uribe, Juan Manuel; Posada, Andrés Fernando; Rosenfeldt, Sabine; Salehi, Sahar; Ionov, Leonid
Skeletal muscle is one of the most abundant tissues in the body. Although it has a relatively good regeneration capacity, it cannot heal in the case of disease or severe damage. Many current tissue engineering strategies fall short due to the complex structure of skeletal muscle. Biofabrication techniques have emerged…
Nucleation and Growth Kinetics of ZnO Nanoparticles Studied by in Situ Microfluidic SAXS/WAXS/UVVis Experiments
Herbst, Maria; Hofmann, Eddie; Förster, Stephan
The synthesis of ZnO nanoparticles proceeds through a complex sequence of precursor reactions, nucleation, and growth processes. For further advancement and control of nanoparticle synthesis, a detailed understanding of the mechanisms and kinetics is essential. With the recent advancement in X-ray scattering and spectroscopy methods, in situ experiments during nanoparticle…
Two Growth Mechanisms of Thiol-Capped Gold Nanoparticles Controlled by Ligand Chemistry
Chen, Xuelian; Wei, Meng; Jiang, Shaohua; Förster, Stephan
Thiols play an important role in the synthesis of well-defined nanoparticles (NPs) with tailored properties, but their effects on the formation kinetics of NPs are still under investigation. Here, we used in situ small-angle X-ray scattering (SAXS)/UVvis spectroscopy and time-dependent transmission electron microscopy (TEM) to elucidate the role of thiols…
Pendant side-chain sterics against electrostatic forces: Influencing short-range ordering in random polyelectrolytes
Nwosu, Chinomso; Coughlin, E. Bryan
The length of pendant side chains in charged, random, comb-shaped polymers dictates the nature of their short-range ordering. Random copolymers, and terpolymer, of 4-vinylpyridine (4VP), styrene, and isoprene were synthesized and subsequently fully quaternized with 1-alkylbromides having varying number of carbons on the alkyl group ranging from 2 to 8.…