Dielectric Breakdown in Silica–Amorphous Polymer Nanocomposite Films: The Role of the Polymer Matrix

Polymers adsorbed on nanoparticles (NPs) are important elements that determine the dispersion of NPs in polymer nanocomposite (PNC) films. While previous studies have shown that increasing the number of adsorbed polymers on NPs can improve their dispersion during the drying process, the exact mechanism remained unclear. In this study, we investigated the role of adsorbed polymers in determining the microstructure and dispersion of NPs during the drying process. Investigation of the structural development of NPs using the synchrotron vertical-small-angle X-ray scattering technique revealed that increasing polymer adsorption suppresses bonding between the NPs at later stages of drying, when they approach each other and come in contact. On the particle length scale, NPs with large amounts of adsorbed polymers form loose clusters, whereas those with smaller amounts of adsorbed polymers form dense clusters. On the cluster length scale, loose clusters of NPs with large amounts of adsorbed polymers build densely packed aggregates, while dense clusters of NPs with small amounts of adsorbed polymers become organized into loose aggregates. The potential for the quantitative control of NP dispersion in PNC films via modification of polymer adsorption was established in this study.

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The Role of Film Processing in the Large-Area Dielectric Breakdown Performance of Nano-Silica-BOPP Films

Proceedings of the Nordic Insulation Symposium ◽

10.5324/nordis.v0i24.2286 ◽

2017 ◽

Author(s):

Ilkka Rytöluoto ◽

Kari Lahti ◽

Mikael Ritamäki ◽

Mikka Karttunen

Keyword(s):

Dielectric Breakdown ◽

Polymer Nanocomposite ◽

Pilot Scale ◽

Silica Content ◽

Nanocomposite Films ◽

Optimum Level ◽

Nano Silica ◽

Large Area ◽

Fill Fraction ◽

Film Processing

<p>This paper summarizes the effects of various compositional, structural and film processing factors on the breakdown behavior of laboratory- and pilot-scale melt-compounded bi-axially oriented polypropylene (BOPP) nanocomposite films with silica fillers. A selfhealing multi-breakdown measurement approach has been extensively utilized for large-area breakdown characterization of a large number of material variants from different processing trials. The results suggest that although the optimum level of silica presumably resides at the low fill-fraction range (~1 wt-%), the silica content itself is not the only determining factor, as compounds with equal silica content were found to exhibit large differences in the breakdown properties depending on the compounding and film processing steps. Dispersion quality and filler agglomeration (in both the nm- and μm-scale) appear to be of great importance. Indications of possible interaction between nano-silica and co-stabilizer Irgafos 168 are also presented. Overall, the laboratory- and pilot-scale film processing trials suggest that up-scaling of the polymer nanocomposite production is sensible with traditional melt-blending technology, although further development and optimization of nanocomposite formulations and processing is necessary.</p>

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Interface modulation in multi-layered BaTiO3 nanofibers/PVDF using the PVP linker layer as an adhesive for high energy density capacitor applications

Materials Advances ◽

10.1039/d0ma00240b ◽

2020 ◽

Vol 1 (4) ◽

pp. 680-688 ◽

Cited By ~ 1

Author(s):

Prateek ◽

Shahil Siddiqui ◽

Ritamay Bhunia ◽

Narendra Singh ◽

Ashish Garg ◽

...

Keyword(s):

Energy Density ◽

Barium Titanate ◽

Polymer Matrix ◽

Polyvinylidene Fluoride ◽

Polymer Nanocomposite ◽

High Energy ◽

High Energy Density ◽

Interface Modulation

In this work, we have studied the role of a linker across the interface in a multi-layered polymer nanocomposite-based capacitor using barium titanate (BT) nanofibers (NFs) as nanofillers and polyvinylidene fluoride (PVDF) as the polymer matrix.

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Role of Molecular Weight in Polymer Wrapping and Dispersion of MWNT in a PVDF Matrix

Polymers ◽

10.3390/polym11010162 ◽

2019 ◽

Vol 11 (1) ◽

pp. 162 ◽

Cited By ~ 1

Author(s):

Muthuraman Namasivayam ◽

Mats R. Andersson ◽

Joseph Shapter

Keyword(s):

Molecular Weight ◽

Electrical Properties ◽

Polymer Matrix ◽

Polymer Nanocomposite ◽

Scanning Calorimetry ◽

Crystallisation Behaviour ◽

Effective Dispersion ◽

Thermal And Electrical Properties ◽

Polymer Wrapping

The thermal and electrical properties of a polymer nanocomposite are highly dependent on the dispersion of the CNT filler in the polymer matrix. Non-covalent functionalisation with a PVP polymer is an excellent driving force towards an effective dispersion of MWNTs in the polymer matrix. It is shown that the PVP molecular weight plays a key role in the non-covalent functionalisation of MWNT and its effect on the thermal and electrical properties of the polymer nanocomposite is reported herein. The dispersion and crystallisation behaviour of the composite are also evaluated by a combination of scanning electron microscopy (SEM) and differential scanning calorimetry (DSC).

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Nanocomposite synthesis by thermolysis of [Ag(hfac)(COD)] in amorphous polystyrene

Science and Engineering of Composite Materials ◽

10.1515/secm-2011-0125 ◽

2012 ◽

Vol 19 (2) ◽

pp. 195-197 ◽

Cited By ~ 4

Author(s):

Gianfranco Carotenuto ◽

Mariano Palomba ◽

Luigi Nicolais

Keyword(s):

Polymer Matrix ◽

Nanocomposite Films ◽

Numerical Density ◽

Silver Particles ◽

X Ray ◽

Transmission Electron ◽

Vis Spectroscopy ◽

Yellow Coloration ◽

Color Filters ◽

Silver Atoms

AbstractLightfast color filters (intensively and brightly colored) can be easily produced by dying optical plastics with the surface plasmon resonance (SPR) of metal nanoparticles such as silver and gold. Here, color filters based on silver nanoparticles embedded in amorphous polystyrene have been prepared by dissolving and thermally decomposing (1,5-cyclooctadiene)(hexafluoro-acetylacetonate)silver(I) in amorphous polystyrene. The metal precursor quickly decomposes (10 s, at 180°C), leading to silver atoms that clusterize and produce a non-aggregated dispersion of silver particles in the polymer matrix. The intensity of the yellow coloration due to the SPR of nanoscopic silver can be widely tuned simply by varying the cluster numerical density in the polymer matrix that depends on the silver precursor concentration. The obtained nanocomposite films have been characterized by X-ray power diffraction, transmission electron microscopy, and UV-Vis spectroscopy.

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Effect of tungsten disulfide nanotubes on crystallization of polylactide under uniaxial deformation and annealing

Functional Composite Materials ◽

10.1186/s42252-021-00016-2 ◽

2021 ◽

Vol 2 (1) ◽

Author(s):

Fausta Loffredo ◽

Loredana Tammaro ◽

Tiziana Di Luccio ◽

Carmela Borriello ◽

Fulvia Villani ◽

...

Keyword(s):

Biomedical Applications ◽

Structural Evolution ◽

Tungsten Disulfide ◽

Fine Tuning ◽

Nanocomposite Films ◽

Uniaxial Deformation ◽

Scanning Calorimetry ◽

X Ray ◽

X Ray Scattering

AbstractTungsten disulfide (WS2) nanotubes (NTs) are examined here as a filler for polylactide (PLA) for their ability to accelerate PLA crystallization and for their promising biocompatibility in relevant to biomedical applications of PLA-WS2 nanocomposites. In this work, we have studied the structural and thermal properties of PLA-WS2 nanocomposite films varying the concentration of WS2 NTs from 0 (neat PLA) to 0.6 wt%. The films were uniaxially drawn at 90 °C and annealed at the same temperature for 3 and 10 min. Using wide angle x-ray scattering, Raman spectroscopy and differential scanning calorimetry, we probed the effects of WS2 NT addition on the structure of the PLA films at various stages of processing (unstretched, stretching, annealing). We found that 0.6 wt% of WS2 induces the same level of crystallinity in as stretched PLA-WS2 as annealing in neat PLA for 10 min. These data provide useful insights into the role of WS2 NTs on the structural evolution of PLA-WS2 composites under uniaxial deformation, and extend their applicability to situations where fine tuning of PLA crystallinity is desirable.

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