Search results for " Nanotubes"
showing 10 items of 289 documents
Bionanocomposites Based on Pectins and Halloysite Nanotubes: from the Structure to the Properties
2010
Multicomponent bionanocomposites based on clay nanoarchitectures for electrochemical devices
2019
[EN] Based on the unique ability of defibrillated sepiolite (SEP) to form stable and homogeneous colloidal dispersions of diverse types of nanoparticles in aqueous media under ultrasonication, multicomponent conductive nanoarchitectured materials integrating halloysite nanotubes (HNTs), graphene nanoplatelets (GNPs) and chitosan (CHI) have been developed. The resulting nanohybrid suspensions could be easily formed into films or foams, where each individual component plays a critical role in the biocomposite: HNTs act as nanocontainers for bioactive species, GNPs provide electrical conductivity (enhanced by doping with MWCNTs) and, the CHI polymer matrix introduces mechanical and membrane pr…
Halloysite-Based Bionanocomposites
2017
Scientific research has been invigorated by a new class of biodegradable materials as alternatives to polymers derived from fossils. Such biomaterials can also offer economic advantages because they are derived from renewable resources. Several biopolymers (gelatin, chitin, chitosan, starch, pectin, cellulose and its modified versions, etc.) have been exploited to produce films and formulations. Their use is limited because of fast degradation, predominant hydrophilic character, and, in some cases, unsatisfactory mechanical properties. However, the properties of these polymers can be improved by using inorganic fillers such as additives. Halloysite nanotube is a promising green filler for t…
Halloysite nanotubes loaded with peppermint essential oil as filler for functional biopolymer film
2016
Abstract The purpose of this paper is to show how a functional bionanocomposite film with both antioxidant and antimicrobial activities was successfully prepared by the filling of a pectin matrix with modified Halloysite nanotubes (HNT) containing the essential peppermint oil (PO). Firstly, HNT surfaces were functionalized with cucurbit[6]uril (CB[6]) molecules with the aim to enhance the affinity of the nanofiller towards PO, which was estimated by means of HPLC experiments. The HNT/CB[6] hybrid was characterized by several methods (thermogravimetry, FT-IR spectroscopy and scanning electron microscopy) highlighting the influence of the supramolecular interactions on the composition, therma…
Stress Transfer within CNT Fibres: A FEA Approach
2015
Abstract Carbon nanotube (CNT) fibres are characterized by extreme anisotropy in their structure and physical properties. These fibres have been shown to have high axial strength, but poor shear strength between carbon nanotubes; for this reason it is difficult to transfer stress uniformly acrossthe fibre cross section. Here, Finite Element Analysis (FEA) is used to predict the stress distribution and the stress-strain curves of CNT fibres. The resultsdemonstrate that, in accordance with St. Venant principle,very considerable length-to-diameter ratios (> 10 3 ) are required to obtain a uniform stress distribution within the fibres even in the presence of low applied strain.
CONTROLLING THE FUNCTIONALIZATION OF CARBON NANOTUBES AND GRAPHENE NANOPLATELETS
2013
The functionalization of carbon nanostructures by diazonium chemistry is a versatile strategy to obtain soluble nanomaterials with degrees of functionalization among the highest ever reported.[1,2] Starting from these premises we have studied the functionalization of single, double and multi-walled carbon nanotubes and graphene nanoplatelets by addition of aryl diazonium salts generated in situ by treatment of 4-substituted anilines with isopentylnitrite. Taking advantage of highly controlled flow synthesis [3-5] and following a thorough purification and characterization protocol (UV-vis, TGA, ATR-IR, AFM and other surface tools), we have investigated the key parameters to obtain both funct…
Thin-Film Heterojunction by Carbon Nanotube Derivatives with Enhanced Solubility and Optical Properties
2012
Multi-functional hybrid-carbon nanotubes for advanced Ultra-High Molecular Weight Polyethylene-based nanocomposites: a novel approach for stabilizati…
2015
Our results demonstrate that immobilizing stabilizing molecules on nanoparticles, and using the latter as multifunctional filler for nanocomposites, is a viable route towards to produce high-performance polymeric materials
THIN-FILM HETROJUNCTION BY CARBON NANOTUBE DERIVATIVES WITH ENHANCED SOLUBILITY AND OPTICAL PROPERTIES
2012
The combination of single-walled carbon nanotubes (SWNTs), characterized by high electron mobility, with p-type semiconducting polymers could lead to an overall improvement in the exciton dissociation and carrier extraction efficiencies in practical devices.1However, one of the main concern in the use of SWNTs, relates to the their scarce solubility. Chemical modification has been widely employed to increase the solubility of SWNTs, but usual reaction conditions limit such syntheses to a small scale with low productivity. Here, we employ SWNTs which have been functionalized with aromatic and heteroaromatic moieties via 1,3-dipolar cycloaddition and through diazotization reaction under batch…