Effect of the type of clay organo-modifier on the morphology, thermal/mechanical/impact/barrier properties and biodegradation in soil of polycaprolactone/clay nanocomposites

2012 ◽  
Vol 128 (5) ◽  
pp. 2648-2657 ◽  
Author(s):  
L. N. Ludueña ◽  
A. Vázquez ◽  
V. A. Alvarez
Keyword(s):  
Barrier Properties ◽  
Clay Nanocomposites ◽  
Mechanical Impact ◽  
Biodegradation In Soil

Natural nanoclays: applications and future trends – a Chilean perspective

Clay Minerals ◽  
2009 ◽  
Vol 44 (2) ◽  
pp. 161-176 ◽  
Author(s):  
M. Calabi Floody ◽  
B. K. G. Theng ◽  
P. Reyes ◽  
M. L. Mora
Keyword(s):  
Agricultural Land ◽  
Clay Fraction ◽  
Barrier Properties ◽  
Clay Nanocomposites ◽  
Volcanic Soils ◽  
Gas Barrier ◽  
Important Species ◽  
The Past ◽  
Organically Modified ◽  
Water And Wastewater

AbstractBecause of their large potential for agricultural, industrial and medicinal applications, nanomaterials have been the focus of much research during the past few decades. Nanoclays are natural nanomaterials that occur in the clay fraction of soil, among which montmorillonite and allophane are the most important species. Montmorillonite is a crystalline hydrous phyllosilicate (layer silicate). Organically-modified montmorillonites or ‘organoclays’, formed by intercalation of quaternary ammonium cations, have long been used as rheological modifiers and additives in paints, inks, greases and cosmetics and as carriers and delivery systems for the controlled release of drugs. Perhaps the largest single usage of organoclays over recent years has been in the manufacture of polymer-clay nanocomposites. These organic–inorganic hybrid materials show superior mechanical, thermal and gas-barrier properties. Organoclays are also useful in pollution control and water treatment. Allophane is a non-crystalline aluminosilicate derived from the weathering of volcanic ash. A large proportion of the agricultural land in Chile is covered by volcanic soils,the clay fraction of which is dominated by allophane. Consisting of nanosize (3.5–5.0 nm) hollow spherules, allophane is a suitable support material for enzyme immobilization. Allophane is also effective at adsorbing phenolic compounds and colour from kraft mill effluents and phosphate from water and wastewater.

Toughening, Thermal Stability, Flame Retardancy, and Scratch–Wear Resistance of Polymer–Clay Nanocomposites

2007 ◽  
Vol 60 (7) ◽  
pp. 496 ◽  
Author(s):  
Aravind Dasari ◽  
Szu-Hui Lim ◽  
Zhong-Zhen Yu ◽  
Yiu-Wing Mai
Keyword(s):  
Thermal Stability ◽  
Wear Resistance ◽  
Flame Retardancy ◽  
Interfacial Area ◽  
Barrier Properties ◽  
Clay Nanocomposites ◽  
Positive Effects ◽  
Large Numbers ◽  
Mechanical And Physical Properties ◽  
Wear Response

Addition of a small percent of clay to polymers improves their stiffness, strength, dimensional stability, and thermal, optical, and barrier properties. Improvements are often attributed to the availability of large numbers of clay nanolayers with tremendous interfacial area. Despite the positive effects from the addition of clay, there are unresolved issues, such as embrittlement, thermal stability, flame retardancy, scratch–wear response of the resultant nanocomposites, and/or achieving a balance between different mechanical and physical properties. In this review, we discuss these issues and the approaches that have been adopted in the expectation of resolving and understanding them, with particular emphasis on our recent and current research.

Interfacial interaction exploration and oxygen barrier potential of polyethylene/poly(ethylene-co-vinyl alcohol)/clay hybrid nanocomposites

e-Polymers ◽  
2017 ◽  
Vol 17 (2) ◽  
pp. 175-185 ◽  
Author(s):  
Zahed Ahmadi
Keyword(s):  
Vinyl Alcohol ◽  
Complex Viscosity ◽  
Barrier Properties ◽  
General Purpose ◽  
Hybrid Nanocomposites ◽  
Polar Component ◽  
Clay Nanocomposites ◽  
One Dimensional ◽  
Poly Ethylene ◽  
Oxygen Barriers

AbstractHybrid nanocomposites based on high-density polyethylene (HDPE)/poly (ethylene-co-vinyl alcohol) (EVOH)/clay were prepared and fully characterized. Morphological (WAXS and TEM), calorimetric (DSC), and dynamic mechanical thermal (DMTA) analyses were applied to investigate potential of nanocomposites as barrier against oxygen. Co-existence of ingredients of different nature, i.e. HDPE (general-purpose non-polar component), EVOH (engineering polar component with excellent barrier properties), nanoclay (planar one-dimensional mineral barrier nanofiller), and maleated HDPE (PE-g-MA) as coupling agent, brings about serious intricacies in view of interaction between existing phases. Conceptual/experimental analysis was performed to explore the interdependence between microstructure and oxygen barrierity of HDPE/EVOH/clay nanocomposites through the lens of interaction state in the system. Morphological measurements confirmed formation of an intercalated nanostructure, while investigations on complex viscosity, storage modulus, permeability, thermo-mechanical properties, and nanoclay interlayer galleries were all indicative of dependence of nanocomposites’ properties on molecular interactions. The performance of nanocomposite sheets as oxygen barriers was mechanistically explained.

Characterizing the nanoclay induced constrained amorphous region in model segmented polyurethane–urea/clay nanocomposites and its implications on gas barrier properties

2016 ◽  
Vol 18 (3) ◽  
pp. 1487-1499 ◽  
Author(s):  
Sangram K. Rath ◽  
Kathi Sudarshan ◽  
Rupesh S. Bhavsar ◽  
Ulhas K. Kharul ◽  
Pradeep K. Pujari ◽  
...  
Keyword(s):  
Barrier Properties ◽  
Amorphous Region ◽  
Clay Nanocomposites ◽  
Segmented Polyurethane ◽  
Gas Barrier ◽  
Gas Barrier Properties

AFM images of the segmented PU/clay nanocomposite with labeling of various phases.

Polymer/clay nanocomposites and their gas barrier properties

2013 ◽  
Vol 34 (9) ◽  
pp. 1418-1424 ◽  
Author(s):  
Alena Kalendova ◽  
Dagmar Merinska ◽  
Jean Francois Gerard ◽  
Miroslav Slouf
Keyword(s):  
Barrier Properties ◽  
Clay Nanocomposites ◽  
Gas Barrier ◽  
Gas Barrier Properties

The Preparation and Characterization of a Novolac Cured Epoxy-Clay Nanocomposites

2006 ◽  
Vol 939 ◽  
Author(s):  
Tsung-Yen Tsai ◽  
Shau-Tai Lu ◽  
Chih-Hung Li ◽  
Chin-Jei Huang ◽  
Li-Chun Chen ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Benzalkonium Chloride ◽  
Barrier Properties ◽  
Layered Silicates ◽  
Clay Nanocomposites ◽  
Crosslinking Reaction ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron

ABSTRACTIntercalated or exfoliated nanocomposites were composed by the novolac cured epoxy and one of three different kinds of layered silicates, such as montmorillonite (PK-802), saponite (Semecton-SA) and nontronite (PK-805). The bi-functional modifiers (PI/BEN or MI/BEN) with different ratio, which contained one of the promoters (2-phenylimidazole, PI and 2-methylimidazole, MI) of epoxy and benzalkonium chloride (BEN), were intercalated into the gallery regions of pure clays at the same time and followed by a crosslinking reaction. The properties of novolac cured epoxy/clay nanocomposites were characterized by wild-angle X-ray diffraction (WAXRD), thermal analysis (TGA/DSC), coefficiency of thermal expansion (TMA), mechanical properties (DMA), and transmission electron microscopy (TEM). According to the measurement, these novolac cured epoxy-clay nanocomposites have shown the significant improvement in the thermal, mechanical and barrier properties.

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