Search results for "Matrix composite"
showing 10 items of 70 documents
The effect of silica nanoparticles on the morphology, mechanical properties and thermal degradation kinetics of polycarbonate
2012
Abstract Polycarbonate/silica nanocomposites with different silica quantities were prepared by a melt compounding method. The effect of silica amount, in the range 1–5 wt.%, on the morphology, mechanical properties and thermal degradation kinetics of polycarbonate (PC) was investigated. Clusters of silica nanoparticles were well dispersed in the polycarbonate whose structure remained amorphous. NMR results showed intermolecular interactions involving the carbonyl groups of different polymeric chains which did not affect the intramolecular rotational motions. The presence of the lowest silica content showed a decrease in the storage and loss moduli below the glass transition temperature, pro…
Spark plasma sintering of zirconia/nano-nickel composites
2015
Open Access
Controlling electrical percolation in multicomponent carbon nanotube dispersions
2011
Carbon nanotube reinforced polymeric composites can have favourable electrical properties, which make them useful for applications such as flat-panel displays and photovoltaic devices. However, using aqueous dispersions to fabricate composites with specific physical properties requires that the processing of the nanotube dispersion be understood and controlled while in the liquid phase. Here, using a combination of experiment and theory, we study the electrical percolation of carbon nanotubes introduced into a polymer matrix, and show that the percolation threshold can be substantially lowered by adding small quantities of a conductive polymer latex. Mixing colloidal particles of different …
Multiwalled carbon nanotube reinforced polymer composites
2008
Due to their high stiffness and strength, as well as their electrical conductivity, carbon nanotubes are under intense investigation as fillers in polymer matrix composites. The nature of the carbon nanotube/polymer bonding and the curvature of the carbon nanotubes within the polymer have arisen as particular factors in the efficacy of the carbon nanotubes to actually provide any enhanced stiffness or strength to the composite. Here the effects of carbon nanotube curvature and interface interaction with the matrix on the composite stiffness are investigated using micromechanical analysis. In particular, the effects of poor bonding and thus poor shear lag load transfer to the carbon nanotube…
ZrTiO4 materials obtained by spark plasma reaction-sintering
2014
Zirconium titanate (ZrTiO4), have many attractive properties such as high resistivity, high dielectric constant, high permittivity at microwave frequencies and excellent temperature stability for microwave properties. Zirconium titanate dense materials are proposed for many structural applications, but fully reacted and completely dense pieces are difficult to obtain by conventional routes. In this work, fully dense zirconium titanate materials (∼98%) were obtained at lower temperatures (1300-1400 C) and short processing time by non-conventional technique; spark plasma-reaction sintering (SPRS). Homogeneous and stable starting powders mixture with the adequate composition was prepared from …
An insight into the interaction between functionalized thermoplastic elastomer and layered double hydroxides through rheological investigations
2018
Abstract Nanocomposites based on maleated poly(styrene-(ethylene-co-butylene)-styrene) copolymer (SEBSgMA) and organo-modified layered double hydroxide (OLDH) have been formulated with the aim to investigate the effects of interfacial interactions between the grafted maleic anhydride groups of the copolymer and the OLDH nanolayers on the rheological properties of nanocomposites. The spectroscopic analysis indicates the establishment of specific polymer/nanofiller interactions, whose extent has been highlighted through morphological and rheological investigations. Specifically, oscillatory melt rheology and shear relaxation tests have been considered in order to deeply investigate the interf…
Durability of basalt/hemp hybrid composites
2017
This study focused on the performance of injection-molded short hemp fibre and hemp/basalt fibre hybrid high density polyethylene composites. Results showed that hybridization with basalt fibre enhanced the performance properties. Analysis of fiber length distribution in the composite and fracture surface was performed to study the fiber breakage and fracture mechanism. Prolonged moisture absorption and accelerated ageing of short hemp fibre and hemp-basalt hybrid reinforced thermoplastic composites was addressed. Ageing in water did not result in a reduction of the strength of the composite samples, while it was found to decrease stiffness of hemp fibre reinforced composites. Mechanical pr…
Multi-functional hindered amine light stabilizers-functionalized carbon nanotubes for advanced ultra-high molecular weight Polyethylene-based nanocom…
2015
Hindered Amine Light Stabilizer (HAS) molecules have been covalently linked on the outer surface of multi-walled carbon nanotubes (CNTs), and the so-obtained multi-functional fillers (HAS-f-CNTs) have been compounded with Ultra High Molecular Weight Polyethylene (UHMWPE) to get composite films. The success of the grafting reaction of the HAS molecules has been confirmed through spectroscopic and thermo-gravimetric analyses. Morphological analyses reveal a segregated microstructure, in which CNT-rich channels surround the polymer domains. This morphology results in improved mechanical properties and appreciable electrical conductive features. More importantly, the addition of only 1 wt.% of …
Effect of moisture on elastic and viscoelastic properties of epoxy and epoxy-based carbon fibre reinforced plastic filled with multiwall carbon nanot…
2016
Abstract In this study, we investigated the peculiarities of moisture absorption and moisture-induced effects on the elastic and viscoelastic flexural properties of epoxy resin and carbon fibre reinforced plastic (CFRP) filled with multiwall carbon nanotubes (MWCNTs). Short-term cyclic creep-recovery tests of moistened epoxy and CFRP filled with MWCNTs revealed improvements in creep resistance for both materials. The addition of MWCNTs to the epoxy resin suppressed the moisture absorption by the material, causing a reduction in the diffusion coefficient by 31% and equilibrium moisture content by 15%. The addition of MWCNTs reduced the flexural strength of moistened epoxy and CFRP samples by…
Effect of external basalt layers on durability behaviour of flax reinforced composites
2016
Abstract Aim of this work is to evaluate the influence of external layers of basalt-mat on the durability behaviour of flax reinforced epoxy composites. To this scope, long-term ageing tests were performed on two different laminates in critical environmental conditions. The first laminate, named Flax, was constituted by stacking ten layers of bidirectional flax fabrics. The second one, named Flax–Basalt, was produced by replacing two external flax layers with two layers of basalt mat for each side of the laminate. Both laminates were exposed to salt-fog environmental conditions, according to ASTM B 117 standard, for 60 days. Five samples per laminate were removed from salt-fog spray chamber…