scholarly journals Enhanced Olefin Transport by SiO2 Particles for Polymer/Ag Metal/Electron Acceptor Composite Membranes

Polymers ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 2316
Author(s):  
Sang Wook Kang
Keyword(s):  
Silica Nanoparticles ◽  
Photoelectron Spectroscopy ◽  
Fumed Silica ◽  
Weight Ratio ◽  
Composite Membranes ◽  
Silica Content ◽  
Mixed Gas ◽  
Scanning Calorimetry ◽  
Fumed Silica Nanoparticles ◽  
Silver Metal

We showed the potential of poly(ethylene-co-propylene) (EPR)/silver metal/p-benzoquinone composite membranes for propylene/propane mixtures, i.e., a selectivity of 10 and a mixed gas permeance of 0.5 GPU (1 GPU = 1 × 10−6 cm3 (STP)/(cm2 s cmHg) in a previous study. In this study, we additionally found that the incorporation of fumed silica nanoparticles into EPR/silver metal/p-benzoquinone (p-BQ) composite membranes exhibited much higher permeance and selectivity for propylene/propane mixtures. The positive polarity of silver metal continuously increased with the increasing silica content up to the 0.1 weight ratio, as revealed by x-ray photoelectron spectroscopy (XPS). This increase in the polarity of silver metal was attributed to the enhanced interaction of p-BQ with the surface of Ag nanoparticles by the increased dispersion of p-BQ by fumed silica nanoparticles. Differential scanning calorimetry (DSC) also presented that the glass transition temperature (Tg) of the membranes was almost invariant. Therefore, the improvement of the permeance and selectivity with the silica nanoparticles was attributable to the increased polarity of the silver metal rather than the structural change.

scholarly journals Role of Surface-Treated Silica Nanoparticles on the Thermo-Mechanical Behavior of Poly(Lactide)

2020 ◽  
Vol 10 (19) ◽  
pp. 6731
Author(s):  
Luca Fambri ◽  
Andrea Dorigato ◽  
Alessandro Pegoretti
Keyword(s):  
Mechanical Behavior ◽  
Silica Nanoparticles ◽  
Fumed Silica ◽  
Mechanical Stability ◽  
Positive Influence ◽  
Poly Lactic Acid ◽  
Scanning Calorimetry ◽  
Fumed Silica Nanoparticles ◽  
Filler Dispersion

Surface-treated fumed silica nanoparticles were added at various concentrations (from 1 to 24 vol%) to a commercial poly(lactide) or poly(lactic acid) (PLA) matrix specifically designed for packaging applications. Thermo-mechanical behavior of the resulting nanocomposites was investigated. Field Emission Scanning Electron Microscopy (FESEM) micrographs revealed how a homogeneous nanofiller dispersion was obtained even at elevated filler amounts, with a positive influence of the thermal degradation stability of the materials. Modelization of Differential Scanning Calorimetry (DSC) curves through the Avrami–Ozawa model demonstrated that fumed silica nanoparticles did not substantially affect the crystallization behavior of the material. On the other hand, nanosilica addition was responsible for significant improvements of the storage modulus (E′) above the glass transition temperature and of the Vicat grade. Multifrequency DMTA tests showed that the stabilizing effect due to nanosilica introduction could be effective over the whole range of testing frequencies. Sumita model was used to evaluate the level of filler dispersion. The obtained results demonstrated the potential of functionalized silica nanoparticles in improving the thermo-mechanical stability of biodegradable matrices for packaging applications, especially at elevated service temperatures.

Effect of Fumed Silica Nanoparticles on the Gas Permeation Properties of Substituted Polyacetylene Membranes

2006 ◽  
Vol 58 (5-6) ◽  
pp. 995-1003 ◽  
Author(s):  
Toshiki Kono ◽  
Yanming Hu ◽  
Toshio Masuda ◽  
Katsuchisa Tanaka ◽  
Rodney D. Priestley ◽  
...  
Keyword(s):  
Silica Nanoparticles ◽  
Fumed Silica ◽  
Gas Permeation ◽  
Fumed Silica Nanoparticles ◽  
Permeation Properties

scholarly journals The Morphology and Conductive Properties of Composite Material SiO2 – C

2015 ◽  
Vol 16 (4) ◽  
pp. 700-705
Author(s):  
I.F. Myronyuk ◽  
V.I. Mandzyuk ◽  
V.M. Sachko ◽  
Yu.O. Kyluk
Keyword(s):  
Composite Material ◽  
Fumed Silica ◽  
Silica Surface ◽  
Weight Ratio ◽  
Nitrogen Adsorption ◽  
Carbon Phase ◽  
Fumed Silica Nanoparticles ◽  
Structure Morphology ◽  
Open Porous Structure ◽  
Conductive Properties

The article explores the structure, morphology and conductive properties of composite material SiO2 – C using XRD, SAXS, low-temperature nitrogen adsorption, and impedance spectroscopy methods. It is set that SiO2 – C composite obtained by thermolytic decomposition of D-lactose, previously chemisorbed on fumed silica nanoparticles surface, has an open porous structure, in which mesopores of 6-12 nm in size are dominate. At weight ratio SiO2/C = 5/1 nanocrystallites of carbon phase in form of lamellar sheets of 0,4 × 0,4 × 5,0 nm3 in size contact with entire silica surface that results in composite material conductivity is 49 Оhm-1·m-1.

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