Search results for "NANOCOMPOSITE"
showing 10 items of 641 documents
Transition to Reinforced State by Percolating Domains of Intercalated Brush-Modified Cellulose Nanocrystals and Poly(butadiene) in Cross-Linked Compo…
2013
The classic nanocomposite approach aims at percolation of low fraction of exfoliated individual reinforcing nanoscale elements within a polymeric matrix. By contrast, many of the mechanically excellent biological nanocomposites involve self-assembled and space-filled structures of hard reinforcing and soft toughening domains, with high weight fraction of reinforcements. Here we inspect a new concept toward mimicking such structures by studying whether percolation of intercalated domains consisting of alternating rigid and reinforcing, and soft rubbery domains could allow a transition to a reinforced state. Toward that, we present the functionalization of rigid native cellulose nanocrystals …
Thermomechanical Analysis of Isora Nanofibril Incorporated Polyethylene Nanocomposites
2021
The research on cellulose fiber-reinforced nanocomposites has increased by an unprecedented magnitude over the past few years due to its wide application range and low production cost. However, the incompatibility between cellulose and most thermoplastics has raised significant challenges in composite fabrication. This paper addresses the behavior of plasma-modified polyethylene (PE) reinforced with cellulose nanofibers extracted from isora plants (i.e., isora nanofibrils (INFs)). The crystallization kinetics of PE&ndash
Thermal and dynamic mechanical properties of beeswax-halloysite nanocomposites for consolidating waterlogged archaeological woods
2015
Abstract Thermal and mechanical properties were determined for the halloysite nanotubes (HNT)/beeswax composites at various compositions. The beeswax degradation temperatures and time course, provided by thermogravimetry (TG), evidenced the improvement of the thermal properties operated by HNT. Differential scanning calorimetry (DSC) allowed us to determine the enthalpy of melting as well as the time course of the melting process for beeswax. A slight loss of beeswax crystallinity was observed upon HNT addition. The dynamical mechanical analysis (DMA) provided the loss and the storage modulus for the nanocomposites upon heating and it was shown that the nanoclays create an inorganic framewo…
Cyclic moisture sorption and its effects on the thermomechanical properties of epoxy and epoxy/MWCNT nanocomposite
2019
The aim of this work was to reveal the moisture absorption&ndash
Structure and dynamics of polyethylene/clay films
2006
The relationships between structure and rheology of polyethylene/clay hybrid composite blown films were investigated through rheological tests both in shear and elongational flow. Two polymer matrices (low density polyethylene, LDPE and linear low density polyethylene, LLDPE) with different relaxation kinetics were used. Independently from the matrix, morphological analyses (TEM, XRD, and SEM) indicate that the hybrid structures are similarly constituted of delaminated platelets or tactoids having a relevant degree of orientation along the draw direction. This strongly affects the rheological behavior of materials. However, despite the similarities emerged from morphological analyses, both …
Preparation of palladated porous nitrogen-doped carbon using halloysite as porogen: disclosing its utility as a hydrogenation catalyst
2020
AbstractIn this article, halloysite nanoclay (Hal) was used as porogen for the synthesis of nitrogen doped porous carbon material with high specific surface area and pore volume. To this purpose, polymerization of melamine and terephthalaldehyde (MT) was performed in the presence of amine-functionalized carbon coated Hal (Hal@Glu-2N) that was prepared from hydrothermal treatment of Hal and glucose. Then, the prepared nanocomposite was palladated and carbonized to afford Pd@Hal@C. To further improve the textural properties of the nanocomposite, and introduce more pores in its structure, Hal nanotubes were etched. The characterization of the resulting compound, Pd@C, and comparing it with Pd@…
Cellulose-inorganic hybrids of strongly reduced thermal conductivity
2022
Abstract The employment of atomic layer deposition and spin coating techniques for preparing inorganic-organic hybrid multilayer structures of alternating ZnO-CNC layers was explored in this study. Helium ion microscopy and X-ray reflectivity showed the superlattice formation for the nanolaminate structures and atomic force microscopy established the efficient control of the CNCs surface coverage on the Al-doped ΖnO by manipulating the concentration of the spin coating solution. Thickness characterization of the hybrid structures was performed via both ellipsometry and X-ray reflectivity and the thermal conductivity was examined by time domain thermoreflectance technique. It appears that ev…
Pickering Emulsions Based on Wax and Halloysite Nanotubes: An Ecofriendly Protocol for the Treatment of Archeological Woods
2020
A novel green protocol for the consolidation and protection of waterlogged archeological woods with wax microparticles has been designed. First, we focused on the development of halloysite nanotubes (HNTs) based Pickering emulsions using wax as the inner phase of the oil-in-water droplets. The optimization of the preparation strategy was supported by both optical microscopy and scanning electron microscopy, which allowed us to show the morphological features of the prepared hybrid systems and their structural properties, i.e., the distribution of the clay at the interface. Also, the dependence of the overall dimensions of the prepared systems on the halloysite content was demonstrated. Micr…
Antimicrobial Bilayer Nanocomposites Based on the Incorporation of As-Synthetized Hollow Zinc Oxide Nanotubes
2020
© 2020 by the authors.
Preparation of graphene nanocomposites from aqueous silver nitrate using graphene oxide’s peroxidase-like and carbocatalytic properties
2020
AbstractThe present study evaluates the role of graphene oxide’s (GO’s) peroxidase-like and inherent/carbocatalytic properties in oxidising silver nitrate (AgNO3) to create graphene nanocomposites with silver nanoparticles (GO/Ag nanocomposite). Activation of peroxidase-like catalytic function of GO required hydrogen peroxide (H2O2) and ammonia (NH3) in pH 4.0 disodium hydrogen phosphate (Na2HPO4). Carbocatalytic abilities of GO were triggered in pH 4.0 deionised distilled water (ddH2O). Transmission electron microscope (TEM), scanning electron microscope (SEM), cyclic voltammetry (CV) and UV-Vis spectroscopy aided in qualitatively and quantitatively assessing GO/Ag nanocomposites. TEM and …