Evaluation of Addition of Carbon Nano Materials Over Properties of an Elastomeric Matrix

In the present work, the effect of the addition of different types of carbon nano structures on the mechanical, thermomechanical and thermal properties of a radial structure of styrene-butadiene-styrene (SBSR) copolymer matrix is reported. Different carbon nanostructures were used as nano-rein-forcements: expanded graphite (XG), graphene oxide (GO), reduced graphene oxide (RGO) and exfo-liated graphene (EG). These carbon structures present various functional groups, such as carbonyl, epoxy, and others, which are the responsible for the interaction between the polymer matrix and the nano particles. The compatibility induced between the nanomaterials and the elastomeric matrix fa-vors the stable dispersion of the nanocomposites during their obtention process. For instance, the ad-dition of GO increased in 10 and 16% the tensile strength and storage modulus of the nanocomposites. The fracture surface patterns in the nanocomposites after the tensile test was observed by scanning electron microscopy. Also, the dynamic mechanical analysis (DMA) and thermal characterization showed differences in the viscoelastic behavior of the reinforced nanocomposites with different carbon nanomaterials.

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Waterborne Graphene- and Nanocellulose-Based Inks for Functional Conductive Films and 3D Structures

Nanomaterials ◽

10.3390/nano11061435 ◽

2021 ◽

Vol 11 (6) ◽

pp. 1435

Author(s):

Jose M. González-Domínguez ◽

Alejandro Baigorri ◽

Miguel Á. Álvarez-Sánchez ◽

Eduardo Colom ◽

Belén Villacampa ◽

...

Keyword(s):

Carbon Nanotubes ◽

Graphene Oxide ◽

Carbon Nanostructures ◽

Carbon Nanomaterials ◽

Electronic Device ◽

Aqueous Media ◽

High Viscosity ◽

Resistance Surface ◽

Conductive Films ◽

Low Viscosity

In the vast field of conductive inks, graphene-based nanomaterials, including chemical derivatives such as graphene oxide as well as carbon nanotubes, offer important advantages as per their excellent physical properties. However, inks filled with carbon nanostructures are usually based on toxic and contaminating organic solvents or surfactants, posing serious health and environmental risks. Water is the most desirable medium for any envisioned application, thus, in this context, nanocellulose, an emerging nanomaterial, enables the dispersion of carbon nanomaterials in aqueous media within a sustainable and environmentally friendly scenario. In this work, we present the development of water-based inks made of a ternary system (graphene oxide, carbon nanotubes and nanocellulose) employing an autoclave method. Upon controlling the experimental variables, low-viscosity inks, high-viscosity pastes or self-standing hydrogels can be obtained in a tailored way. The resulting inks and pastes are further processed by spray- or rod-coating technologies into conductive films, and the hydrogels can be turned into aerogels by freeze-drying. The film properties, with respect to electrical surface resistance, surface morphology and robustness, present favorable opportunities as metal-free conductive layers in liquid-phase processed electronic device structures.

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Dynamic Mechanical Behavior of Graphene Oxide Functionalized Curaua Fiber-Reinforced Epoxy Composites: A Brief Report

Polymers ◽

10.3390/polym13111897 ◽

2021 ◽

Vol 13 (11) ◽

pp. 1897

Author(s):

Ulisses Oliveira Costa ◽

Lucio Fabio Cassiano Nascimento ◽

Wendell Bruno Almeida Bezerra ◽

Vinícius de Oliveira Aguiar ◽

Artur Camposo Pereira ◽

...

Keyword(s):

Graphene Oxide ◽

Epoxy Matrix ◽

Natural Fiber ◽

Viscoelastic Behavior ◽

Mechanical Analysis ◽

Neat Epoxy ◽

Damping Factor ◽

Fiber Reinforced ◽

Dynamic Mechanical ◽

Curauá Fiber

The coating of natural fiber by graphene oxide (GO) has, over, this past decade, attracted increasing attention as an effective way to improve the adhesion to polymer matrices and enhance the composite properties. In particular, the GO-functionalized 30 vol% curaua fiber (Ananas Erectifolius) reinforcing epoxy composite was found to display superior tensile and thermogravimetric properties as well as higher fiber/matrix interfacial shear strength. In this brief report, dynamic mechanical analysis (DMA) was conducted in up to 50 vol% GO-functionalized curaua fiber reinforced epoxy matrix (EM) composites. The objective was not only to extend the amount incorporated but also for the first time investigate the composite viscoelastic behavior. The GO functionalization of curaua fibers (GOCF) improved the DMA storage (E′) and loss (E″) modulus compared to the non-functionalized fiber composites. Values at 30 °C of both E′ (13.44 GPa) and E″ (0.67 GPa) for 50 vol% GO-functionalized curaua fiber reinforced epoxy matrix composites (50GOCF/EM) were substantially higher than those of 20 GOCF/EM with E′ (7.08 GPa) and E″ (0.22 GPa) as well as non-functionalized 50CF/EM with E′ (11.04 GPa) and E″ (0.45 GPa). All these results are above the neat epoxy previously reported values of E′ (3.86 GPa) and E″ (0.09 GPa). As for the tangent delta, the parameters associated with damping factor and glass transition temperature were not found to be significantly changed by GO functionalization, but decreased with respect to the neat epoxy due to chain mobility restriction.

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Extruded PLA Nanocomposites Modified by Graphene Oxide and Ionic Liquid

Polymers ◽

10.3390/polym13040655 ◽

2021 ◽

Vol 13 (4) ◽

pp. 655

Author(s):

Cristian Sánchez-Rodríguez ◽

María-Dolores Avilés ◽

Ramón Pamies ◽

Francisco-José Carrión-Vilches ◽

José Sanes ◽

...

Keyword(s):

Ionic Liquid ◽

Graphene Oxide ◽

Viscoelastic Behavior ◽

Mechanical Analysis ◽

Twin Screw Extrusion ◽

Scanning Calorimetry ◽

Screw Extrusion ◽

Ir And Raman Spectroscopies ◽

Twin Screw ◽

Ft Ir

Polylactic acid (PLA)-based nanocomposites were prepared by twin-screw extrusion. Graphene oxide (GO) and an ionic liquid (IL) were used as additives separately and simultaneously. The characterization of the samples was carried out by means of Fourier transform infrared (FT-IR) and Raman spectroscopies, thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). The viscoelastic behavior was determined using dynamic mechanical analysis (DMA) and rheological measurements. IL acted as internal lubricant increasing the mobility of PLA chains in the solid and rubbery states; however, the effect was less dominant when the composites were melted. When GO and IL were included, the viscosity of the nanocomposites at high temperatures presented a quasi-Newtonian behavior and, therefore, the processability of PLA was highly improved.

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A Bottom-Up Approach to Solution-Processed, Atomically Precise Graphitic Cylinders on Surfaces

10.26434/chemrxiv.7158959 ◽

2018 ◽

Author(s):

Erik Leonhardt ◽

Jeff M. Van Raden ◽

David Miller ◽

Lev N. Zakharov ◽

Benjamin Aleman ◽

...

Keyword(s):

Self Assembly ◽

Carbon Nanostructures ◽

Carbon Nanomaterials ◽

Circle Packing ◽

Pyrolytic Graphite ◽

Building Blocks ◽

Bottom Up ◽

Casting Technique ◽

New Class ◽

Solution Casting Technique

Extended carbon nanostructures, such as carbon nanotubes (CNTs), exhibit remarkable properties but are difficult to synthesize uniformly. Herein, we present a new class of carbon nanomaterials constructed via the bottom-up self-assembly of cylindrical, atomically-precise small molecules. Guided by supramolecular design principles and circle packing theory, we have designed and synthesized a fluorinated nanohoop that, in the solid-state, self-assembles into nanotube-like arrays with channel diameters of precisely 1.63 nm. A mild solution-casting technique is then used to construct vertical “forests” of these arrays on a highly-ordered pyrolytic graphite (HOPG) surface through epitaxial growth. Furthermore, we show that a basic property of nanohoops, fluorescence, is readily transferred to the bulk phase, implying that the properties of these materials can be directly altered via precise functionalization of their nanohoop building blocks. The strategy presented is expected to have broader applications in the development of new graphitic nanomaterials with π-rich cavities reminiscent of CNTs.

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Nanocomposites for Enhanced Osseointegration of Dental and Orthopedic Implants Revisited: Surface Functionalization by Carbon Nanomaterial Coatings

Journal of Composites Science ◽

10.3390/jcs5010023 ◽

2021 ◽

Vol 5 (1) ◽

pp. 23

Author(s):

Moon Sung Kang ◽

Jong Ho Lee ◽

Suck Won Hong ◽

Jong Hun Lee ◽

Dong-Wook Han

Keyword(s):

Surface Functionalization ◽

Carbon Nanostructures ◽

Carbon Nanomaterials ◽

Orthopedic Implants ◽

Carbon Nanodots ◽

Biological Studies ◽

Electrochemical Coatings ◽

Thermal And Electrical Properties ◽

Novel Strategy ◽

Clinical Potential

Over the past few decades, carbon nanomaterials, including carbon nanofibers, nanocrystalline diamonds, fullerenes, carbon nanotubes, carbon nanodots, and graphene and its derivatives, have gained the attention of bioengineers and medical researchers as they possess extraordinary physicochemical, mechanical, thermal, and electrical properties. Recently, surface functionalization with carbon nanomaterials in dental and orthopedic implants has emerged as a novel strategy for reinforcement and as a bioactive cue due to their potential for osseointegration. Numerous developments in fabrication and biological studies of carbon nanostructures have provided various novel opportunities to expand their application to hard tissue regeneration and restoration. In this minireview, the recent research trends in surface functionalization of orthopedic and dental implants with coating carbon nanomaterials are summarized. In addition, some seminal methodologies for physicomechanical and electrochemical coatings are discussed. In conclusion, it is shown that further development of surface functionalization with carbon nanomaterials may provide innovative results with clinical potential for improved osseointegration after implantation.

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Viscoelastic behavior of suspensions of reduced graphene oxide nanoparticles in epoxy

Applied Physics Letters ◽

10.1063/5.0059951 ◽

2021 ◽

Vol 119 (4) ◽

pp. 041901

Author(s):

M. Majidian ◽

A. Magrez ◽

L. Forró ◽

Y. Leterrier

Keyword(s):

Graphene Oxide ◽

Reduced Graphene Oxide ◽

Viscoelastic Behavior ◽

Oxide Nanoparticles ◽

Reduced Graphene

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Molecular Dynamic Simulation of Carbon Nanostructures Formation

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1040.92 ◽

2014 ◽

Vol 1040 ◽

pp. 92-96

Author(s):

Denis A. Tatarnikov ◽

Aleksey V. Godovykh

Keyword(s):

Thermodynamic Properties ◽

Molecular Dynamic Simulation ◽

Molecular Dynamic ◽

Dynamic Simulation ◽

Carbon Nanostructures ◽

Carbon Nanomaterials ◽

Statistical Data ◽

New Materials ◽

Molecular Dynamic Simulation Study ◽

Stable Structures

This paper is devoted to the study of stable structures of various carbon nanomaterials using molecular dynamic simulation, study of their properties and characteristics, as well as search for possible later use in nanoelectronics and nanomechanics. We develop programs for computation of the system of atoms at every step and visualization of that data, also we research of thermodynamic properties and conditions of formation of different carbon nanostructures, try to predict existence of new materials. Nowadays we have two separate programs: one for computation and one for visualization. We continue to collect statistical data, investigate behavior of the system under different conditions.

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Reversible Actuation Ability upon Light Stimulation of the Smart Systems with Controllably Grafted Graphene Oxide with Poly (Glycidyl Methacrylate) and PDMS Elastomer: Effect of Compatibility and Graphene Oxide Reduction on the Photo-Actuation Performance

Polymers ◽

10.3390/polym10080832 ◽

2018 ◽

Vol 10 (8) ◽

pp. 832 ◽

Cited By ~ 10

Author(s):

Josef Osicka ◽

Miroslav Mrlik ◽

Marketa Ilcikova ◽

Barbora Hanulikova ◽

Pavel Urbanek ◽

...

Keyword(s):

Graphene Oxide ◽

Glycidyl Methacrylate ◽

Mechanical Response ◽

Dynamic Mechanical Properties ◽

Light Stimulation ◽

Smart Systems ◽

Elastomeric Matrix ◽

Chain Mobility ◽

Angle Measurements ◽

Stimulation Of

This study is focused on the controllable reduction of the graphene oxide (GO) during the surface-initiated atom transfer radical polymerization technique of glycidyl methacrylate (GMA). The successful modification was confirmed using TGA-FTIR analysis and TEM microscopy observation of the polymer shell. The simultaneous reduction of the GO particles was confirmed indirectly via TGA and directly via Raman spectroscopy and electrical conductivity investigations. Enhanced compatibility of the GO-PGMA particles with a polydimethylsiloxane (PDMS) elastomeric matrix was proven using contact angle measurements. Prepared composites were further investigated through the dielectric spectroscopy to provide information about the polymer chain mobility through the activation energy. Dynamic mechanical properties investigation showed an excellent mechanical response on the dynamic stimulation at a broad temperature range. Thermal conductivity evaluation also confirmed the further photo-actuation capability properties at light stimulation of various intensities and proved that composite material consisting of GO-PGMA particles provide systems with a significantly enhanced capability in comparison with neat GO as well as neat PDMS matrix.

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Copper Containing Glass-Based Bone Adhesives for Orthopaedic Applications: Glass Characterization and Advanced Mechanical Evaluation

10.1101/2020.11.19.390138 ◽

2020 ◽

Author(s):

Sahar. Mokhtari ◽

Anthony.W. Wren

Keyword(s):

Mechanical Properties ◽

Photoelectron Spectroscopy ◽

Structural Changes ◽

Viscoelastic Behavior ◽

Polymer Chains ◽

Nano Particles ◽

X Ray Diffraction ◽

X Ray ◽

Compression Data

AbstractThis study addresses issues with currently used bone adhesives, by producing novel glass based skeletal adhesives through modification of the base glass composition to include copper (Cu) and by characterizing each glass with respect to structural changes. Bioactive glasses have found applications in fields such as orthopedics and dentistry, where they have been utilized for the restoration of bone and teeth. The present work outlines the formation of flexible organic-inorganic polyacrylic acid (PAA) – glass hybrids, commercial forms are known as glass ionomer cements (GICs). Initial stages of this research will involve characterization of the Cu-glasses, significant to evaluate the properties of the resulting adhesives. Scanning electron microscopy (SEM) of annealed Cu glasses indicates the presence of partial crystallization in the glass. The structural analysis of the glass using Raman suggests the formation of CuO nanocrystals on the surface. X-ray diffraction (XRD) pattern and X-ray photoelectron spectroscopy (XPS) further confirmed the formation of crystalline CuO phases on the surface of the annealed Cu-glass. The setting reaction was studied using Fourier transform infrared spectroscopy (ATR-FTIR). The mechanical properties of the Cu containing adhesives exhibited gel viscoelastic behavior and enhanced mechanical properties when compared to the control composition. Compression data indicated the Cu glass adhesives were efficient at energy dissipation due to the reversible interactions between CuO nano particles and PAA polymer chains.

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The Role of Bio-Extracted Reduced Graphene Oxide in the Crystallization Kinetics of Chitosan Bio-Polymer

10.47363/jmsmr/2021(2)112 ◽

2021 ◽

pp. 1-4

Author(s):

Solomon L Joseph ◽

◽

Agumba O John ◽

Fanuel M Keheze ◽

◽

...

Keyword(s):

Graphene Oxide ◽

Reduced Graphene Oxide ◽

Carbon Nanomaterials ◽

High Strength ◽

Limiting Factor ◽

Reduced Graphene ◽

Electrical Conductivities ◽

Coating Method ◽

Potential Applications ◽

New Applications

Carbon nanomaterials have recently attracted wide scientific applications due to their tunable properties. These novel materials act as best fillers that can provide substantial benefits due to their high strength, thermal conductivity, and electrical conductivities. With their huge applications as bulk materials, when implemented in polymer matrix as fillers, they give rise to new promising materials with which their properties can be tuned to suit a particular application. Besides the development of these new nanocomposite materials, there exist some challenges which must be fully surpassed to explore the potentiality of application of carbon-based nanocomposites. Reduced graphene oxide is one of the carbon derivatives which has attracted the current advancement in technology, and recently, it found its new applications in super capacitors used in electronic industries. The limiting factor for its exploration is the affordability. New and affordable sources of these graphene-based nanomaterial have to be devised, for fully realization of their potential applications. In this study, reduced graphene oxide and the bio-polymer chitosan were extracted from the locally available bio waste materials. Nanocomposites were prepared at 50% rGO: chitosan ratio. The films were then prepared by spin coating method. Prepared films were subjected to morphological analysis. From the results, it was observed that rGO induced chitosan crystallization, which led to formation of dendritic structures. Cellulose nanocrystals have thus displayed temperature dependent positive uniaxial birefringence

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