Polystyrene–organoclay nanocomposites prepared by melt intercalation, in situ, and masterbatch methods

2006 ◽  
Vol 27 (3) ◽  
pp. 249-255 ◽  
Author(s):  
Ulku Yilmazer ◽  
Gulsum Ozden
Keyword(s):  
Melt Intercalation

Clay mineral/polyamide nanocomposites obtained by in-situ polymerization or melt intercalation

2013 ◽  
Vol 83-84 ◽  
pp. 294-299 ◽  
Author(s):  
Rudolf Puffr ◽  
Jana Lišková Špátová ◽  
Jiří Brožek
Keyword(s):  
Clay Mineral ◽  
In Situ Polymerization ◽  
Melt Intercalation

scholarly journals Poly(η-caprolactone) layered silicate nanocomposites: effect of clay surface modifiers on the melt intercalation process

e-Polymers ◽  
2001 ◽  
Vol 1 (1) ◽  
Author(s):  
Nadège Pantoustier ◽  
Michaël Alexandre ◽  
Philippe Degée ◽  
Cédric Calberg ◽  
Robert Jérôme ◽  
...  
Keyword(s):  
In Situ Polymerization ◽  
Layered Silicate ◽  
Ammonium Cation ◽  
Mechanical And Thermal Properties ◽  
Melt Intercalation ◽  
Silicate Nanocomposites ◽  
Transmission Electron ◽  
Biodegradable Poly ◽  
Cation Type

AbstractNanocomposites based on biodegradable poly(e-caprolactone) (PCL) and layered silicates (montmorillonite) modified by various alkylammonium cations were prepared by melt intercalation. Depending on whether the ammonium cations contain non-functional alkyl chains or chains terminated by carboxylic acid or hydroxyl functions, microcomposites or nanocomposites were recovered as shown by X-ray diffraction and transmission electron microscopy. Mechanical and thermal properties were examined by tensile testing and thermogravimetric analysis. The layered silicate PCL nanocomposites exhibited some improvement of the mechanical properties (higher Young’s modulus) and increased thermal stability as well as enhanced flame retardant characteristics as result of a charring effect. This communication aims at reporting that the formation of PCL-based nanocomposites strictly depends on the nature of the ammonium cation and its functionality, but also on the selected synthetic route, i.e. melt intercalation vs. in situ intercalative polymerization. Typically, protonated w-aminododecanoic acid exchanged montmorillonite allowed to intercalate ε -caprolactone monomer and yielded nanocomposites upon in situ polymerization, whereas they exclusively formed microcomposites when blended with preformed PCL chains. In other words, it is shown that the formation of polymer layered silicate nanocomposites is not straightforward and cannot be predicted since it strongly depends on parameters such as ammonium cation type and functionality together with the production procedure, i.e., melt intercalation, solvent evaporation or in situ polymerization.

Fabrication of poly(β-cyclodextrin-co-citric acid)/bentonite clay nanocomposite hydrogel: thermal and absorption properties

RSC Advances ◽  
2015 ◽  
Vol 5 (100) ◽  
pp. 82438-82449 ◽  
Author(s):  
Abolfazl Heydari ◽  
Hassan Sheibani
Keyword(s):  
Citric Acid ◽  
Bentonite Clay ◽  
Nanocomposite Hydrogel ◽  
Absorption Properties ◽  
Melt Intercalation ◽  
Intercalative Polymerization

A β-cyclodextrin (β-CD)/bentonite clay (BNC) nanocomposite hydrogel was prepared through combining in situ intercalative polymerization and melt intercalation methods.

Rendez vous with Saturn's rings

1984 ◽  
Vol 75 ◽  
pp. 743-759 ◽  
Author(s):  
Kerry T. Nock
Keyword(s):  
Solar Energy ◽  
Electric Propulsion ◽  
Power Source ◽  
Propulsion System ◽  
Low Thrust ◽  
Ring Plane ◽  
The Earth ◽  
Total Impulse ◽  
Saturn's Rings

ABSTRACTA mission to rendezvous with the rings of Saturn is studied with regard to science rationale and instrumentation and engineering feasibility and design. Future detailedin situexploration of the rings of Saturn will require spacecraft systems with enormous propulsive capability. NASA is currently studying the critical technologies for just such a system, called Nuclear Electric Propulsion (NEP). Electric propulsion is the only technology which can effectively provide the required total impulse for this demanding mission. Furthermore, the power source must be nuclear because the solar energy reaching Saturn is only 1% of that at the Earth. An important aspect of this mission is the ability of the low thrust propulsion system to continuously boost the spacecraft above the ring plane as it spirals in toward Saturn, thus enabling scientific measurements of ring particles from only a few kilometers.

The Use of Advanced Analytical Techniques for Characterization of the Chemical, Physical, and Crystallographic Nature of a Surface

1973 ◽  
Vol 31 ◽  
pp. 132-133 ◽  
Author(s):  
R. E. Herfert
Keyword(s):  
Surface Characterization ◽  
Analytical Techniques ◽  
X Ray Diffraction ◽  
Depth Of Penetration ◽  
X Ray ◽  
The Past ◽  
Transmission Electron ◽  
Scanning Electron

Studies of the nature of a surface, either metallic or nonmetallic, in the past, have been limited to the instrumentation available for these measurements. In the past, optical microscopy, replica transmission electron microscopy, electron or X-ray diffraction and optical or X-ray spectroscopy have provided the means of surface characterization. Actually, some of these techniques are not purely surface; the depth of penetration may be a few thousands of an inch. Within the last five years, instrumentation has been made available which now makes it practical for use to study the outer few 100A of layers and characterize it completely from a chemical, physical, and crystallographic standpoint. The scanning electron microscope (SEM) provides a means of viewing the surface of a material in situ to magnifications as high as 250,000X.

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