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Showing 1 to 20 of 20 for “"layered silicate"”.
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Hierarchical layered-silicate-- lamellar triblock copolymer nanocomposites
The fundamental role of the layered-silicates in a styrene-butadiene-styrene triblock copolymer (SBS) as a function of layered-silicate dispersion during deformation was investigated. Predominantly immiscible composites of mixed morphology provided the initial proof that dramatic alteration of the …
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Micro/nanoscale modeling of anisotropic mechanical properties of polymer/layered-silicate nanocomposites
… from molecular dynamics simulations of silicate layer stiffness. The predictions of macroscopic stiffness from these two-dimensional micromechanical models, based on structure-dependent particle volume fraction and properties, are consistent with experimental observations. Furthermore, …
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Thermal and transport properties of layered silicate nanomaterials subjected to extreme thermal cycling
… extreme thermal environments. Polymer-layered nanocomposites were studied to determine if they can reduce the permeation to the liquid nitrogen used as fuel in the next generation of space vehicles. Due to the non-permeable nature of the silicates and the exfoliated structure they adopt …
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Improving the Exfoliation of Layered Silicate in a Poly(ethylene terephthalate) Matrix Using Supercritical Carbon Dioxide
… the level of exfoliation achievable in a PET-layered silicate nanocomposite produced from melt compounding. Layered silicate and scCO2 were allowed to mix for a period of time before being released into the second stage of a single screw extruder. The rapid expansion forced silicate particles …
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Free-radical maleation of poly(butylene adipate-co-terephthalate) in supercritical carbon dioxide and its effect on the percolation and deformation mechanism of layered silicate nanocomposites
The utilization of compostable polymers such as poly(butylene adipate-co-terephthalate) (PBAT) in single-use packaging applications can mitigate the water, solvents, and energy required for processing plastic waste. PBAT exhibits exceptional elongational properties, but its moderate water vapor …
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Schichtsilicate als effiziente Bausteine für funktionelle Nanokomposite
… the progressive generation of efficient polymer layered silicate nano-composites is described within this thesis. These nanocomposites require the optimization of four crucial factors, the aspect ratio and the mechanical properties of the nanofiller, as well as its compatibilization with and …
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Morphological properties of poly (ethylene terephthalate) (PET) nanocomposites in relation to fracture toughness.
The effect of incorporation of montmorillonite layered silicate (MLS) on poly (ethylene terephthalate) (PET) matrix was investigated. MLS was added in varying concentration of 1 to 5 weight percent in the PET matrix. DSC and polarized optical microscopy were used to determine the crystallization …
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Saturation and foaming of thermoplastic nanocomposites using supercritical CO2.
… a range of concentrations of montmorillonite layered silicate (MLS). The polymerized samples were then compression molded into 1 to 2mm thick laminates. The laminates were foamed in a batch supercritical CO2 process at various temperatures and pressures from 60°-85°C and 7.6-12MPa. The …
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The Effect of Matrix Molecular Weight on the Dispersion of Nanoclay in Unmodified High Density Polyethylene
… polyethylene (HDPE) was examined. Polymer layered silicate (PLS) nanocomposites were compounded using three unmodified HDPE matrices of differing molecular weight and an organically modified MMT in concentrations ranging from 2 wt% to 8 wt% via single screw extrusion. The weight average …
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Bulk and Interfacial Effects on Density in Polymer Nanocomposites
… PEN were processed by extrusion. Montmorillonite layered silicate (MLS) in a range of concentrations from 1 to 5% was blended with all three resins. Dispersion of the MLS in the matrix was investigated by using one or a combination of X-ray diffraction (XRD), scanning electron microscopy (SEM) and …
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Polymer-organoclay nanocomposites by melt processing
Polymer-layered silicate nanocomposites based on a variety of polymer matrices and several organoclays were prepared by melt processing. A detailed characterization of the thermal degradation of several commercial and experimental organoclays often used to form polymer nanocomposites was reported. …
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The Chemistry of Dimethacrylate-Styrene Networks and Development of Flame Retardant, Halogen-Free Fiber Reinforced Vinyl Ester Composites
… system investigated was a polycaprolactone layered silicate nanocomposite, which was prepared via intercalative polymerization. Transmission Electron Microscopy (TEM) and X-ray Diffraction (XRD) data indicated a mixed morphology of exfoliated and intercalated structures. The mechanical …
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The Manufacture and Mechanical Properties of Poly(ethylene terephthalate) Fibers Filled with Organically-Modified Montmorillonite
… terephthalate), PET, fibers by the addition of layered silicate nanoparticles and by drawing the un-oriented nanocomposite filaments in a second step. No previous studies on PET fibers filled with montmorillonite (MMT) nanoclay examined fiber drawability at temperatures above the glass …
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Development and evaluation of fire retardent unsaturated polyester clay nanocomposites.
… was followed by in-depth studies of the polymer layered silicate nanocomposite (PLSN) materials. A range of commercial nanoclays were sourced, and characterised. In addition a range of modified clays were developed to improve fire performance and compatibility. Intercalated nanoclays in polyester …
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Mg-Al Layered Double Hydroxide: A Potential Nanofiller and Flame-Retardant for Polyethylene
… the investigation of magnesium aluminum based layered double hydroxide (LDH) as a potential nanofiller and flame-retardant for polymers with special reference to polyethylene. LDH is a mixed hydroxide of di- and trivalent metal ions that crystallizes in the form of mineral brucite. The basic …
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Understanding and Controlling Failure Mechanisms of the Zinc Anode for Rechargeable Alkaline Batteries
… ammonium bromide (CTAB), and a synthetic layered silicate with trade name Laponite. Reduced KOH concentration extends cycle life due to reduced solubility of the zinc oxide formed during discharge and in turn increased anode mass retention. In 20 wt% KOH at 15% Zn utilization, the …
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Elastomer / Schichtsilikat Komposite : Einfluss der Füllstoffstruktur auf mechanische, dynamische und Gasbarriere-Eigenschaften
Füllstoffe sind aus polymeren Werkstoffen nicht mehr wegzudenken, denn meist dienen sie nicht nur der Kostenersparnis, sondern der Eigenschaftsverbesserung, insbesondere der Verstärkung. Dabei spielen deren Dispergierung und die Füllstoffnetzwerkbildung eine entscheidende Rolle. Die wichtigsten …
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Optimierung der Barriereeigenschaften hybridpolymerer Beschichtungssysteme
Quellfähige natürliche Schichtsilicate können nach vorheriger Modifizierung als nanoskalige Barrierefüllstoffe für hybridpolymere Beschichtungen eingesetzt werden. Durch Ionenaustausch nach der „Onium-Methode“ wurden aus natürlichem Montmorillonit unterschiedlich modifizierte organophile …
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Melt Synthesis, Structural, Characterization and Scaling of Swelling 2:1-Layer Silicate Materials
… single crystal structures of swelling 2:1-layer silicates were the main fundamental topics of the presented thesis. In particular, large scale syntheses of both lithium and sodium fluorohectorite were successfully achieved. Furthermore, the crystal structure of one-, and two-layer hydrate of …
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Extrusion von massgeschneiderten thermoplastischen Nanocompositen auf der Basis von organophil modifizierten Schichtsilikaten
In dieser Arbeit wurden auf der Basis von organophil modifizierten Schichtsilikaten thermoplastische Nanocomposite durch Schmelzextrusion hergestellt. Dabei konnte gezeigt werden, dass die Schichtsilikatschichten in der Polymermatrix homogen dispergierbar waren, was eine sehr gute …