Novel Ultrasonic Dispersion of Carbon Nanotubes

Caneba, Gerard T.; Dutta, Chayan; Agrawal, Vinamra; Rao, Martha Purnachander

doi:10.4236/jmmce.2010.93015

Cited by 26 publications

(23 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Solubilization of CNTs is performed by both physical and chemical processing [33]. In the first case, we can mention ultrasounds [104], gel electrophoresis [105], dielectrophoresis [106], chromatography [107], density gradient ultracentrifugation [108]. Other methods such as plasma treatments, and UV light [109] are utilized for modifying the surface chemistry grafting polar functional groups.…”

Section: Carbon Nanotubesmentioning

confidence: 99%

The Role of Functionalization in the Applications of Carbon Materials: An Overview

Speranza

2019

View full text Add to dashboard Cite

The carbon-based materials (CbMs) refer to a class of substances in which the carbon atoms can assume different hybridization states (sp 1 , sp 2 , sp 3 ) leading to different allotropic structures -. In these substances, the carbon atoms can form robust covalent bonds with other carbon atoms or with a vast class of metallic and non-metallic elements, giving rise to an enormous number of compounds from small molecules to long chains to solids. This is one of the reasons why the carbon chemistry is at the basis of the organic chemistry and the biochemistry from which life on earth was born. In this context, the surface chemistry assumes a substantial role dictating the physical and chemical properties of the carbon-based materials. Different functionalities are obtained by bonding carbon atoms with heteroatoms (mainly oxygen, nitrogen, sulfur) determining a certain reactivity of the compound which otherwise is rather weak. This holds for classic materials such as the diamond, the graphite, the carbon black and the porous carbon but functionalization is widely applied also to the carbon nanostructures which came at play mainly in the last two decades. As a matter of fact, nowadays, in addition to fabrication of nano and porous structures, the functionalization of CbMs is at the basis of a number of applications as catalysis, energy conversion, sensing, biomedicine, adsorption etc. This work is dedicated to the modification of the surface chemistry reviewing the different approaches also considering the different macro and nano allotropic forms of carbon.C 2019, 5, 84 3 of 45 narrow graphite-like interconnected layers. This leads to a closed pore rigid structure that is chemically inert, hard but brittle [48][49][50].Due to the highly resistant, conductive, and inert network, glassy carbons are utilized in a series of rather different applications. They are utilized as electrodes in solid state batteries and in industrial harsh chemical processes where also high temperatures are involved such as crystallization of CaF2, CdS and ZnS. Glassy carbon can be utilized to manufacture high temperature furnace elements. Due to the chemical inertness, glassy carbons are utilized also in fabrication of protheses. Porous carbon and carbon black are much softer. Generally, in industrial applications important is the extension of the surface which is exposed to the external environment. The porous carbon is characterized by a high specific surface area enhancing the interaction with the external medium. Although it possesses a lower conductivity with respect to glassy carbon, the high porosity and the presence of active sites makes it a good material to fabricate electrodes for applications in electrochemistry [51][52][53] and bioelectrodes for sensing and stimulation [54,55].The same holds for the carbon black mainly utilized as additive in rubbers and polymers to improve their mechanical properties, or as a pigment [56] although new potentialities have been recently envisaged [57].Common to all the forms of carbon which are bri...

show abstract

Section: Carbon Nanotubesmentioning

confidence: 99%

The Role of Functionalization in the Applications of Carbon Materials: An Overview

Speranza

2019

View full text Add to dashboard Cite

show abstract

“…DMF is highly compatible with the Nafion tetrafluoroethylene backbone, and thus enables the formation of a membrane in which the Nafion molecules do not aggregate [17]. It is also used as a solution for carbon nanotube (CNT) dispersions such as for surfactants [18][19][20]. However, in the Nafion membrane casting process, it proved to be difficult to acquire a uniform…”

Section: Introductionmentioning

confidence: 99%

Effect of Ionic Polymer Membrane with Multiwalled Carbon Nanotubes on the Mechanical Performance of Ionic Electroactive Polymer Actuators

et al. 2020

View full text Add to dashboard Cite

Ionic electroactive polymer (IEAP) actuators have received interest because of their advantageous properties, including their large displacement, high energy density, light weight, and low power consumption under a low electric field. However, they have a low blocking force under driving, and it is difficult to control the thickness of the ionic polymer membrane. In this study, an IEAP actuator is fabricated using a Nafion membrane with added multiwalled carbon nanotubes to increase the blocking force. A heat press two-step process is also developed to produce a constant and uniform membrane. The fabricated Nafion membrane with 0.2 wt% multiwalled carbon nanotubes has the largest displacement and highest blocking force. As a result, the developed heat press two-step method can be used in various polymer-casting fields, and the fabricated carbon nanotube-based IEAP actuators can serve as useful references in fields such as flexible robotics and artificial muscles.Polymers 2020, 12, 396 2 of 10 membrane with a controlled thickness. So, after the casting process, a new method of controlling the thickness through additional processes was needed. The heat press is good because it can process heat and pressure at the same time, but the fine and constant thickness control method needs to be further investigated. Therefore, the process using the metal plate and the heat press was further performed after the casting to obtain a uniform membrane having a controlled thickness.Moreover, IEAP actuators have significant drawbacks such as low actuation bandwidth, low blocking force, and poor durability [21][22][23][24]. Their low blocking force has particularly hindered the practical applicability of IEAP actuators, necessitating studies on increasing their blocking force. The thicker membrane layer or the thicker electrode layer can cause a displacement decrease of the actuator [8][9][10], and the stiffer electrode layer can cause cracks on the electrode surface, and poor durability of the actuator in operation. Therefore, the application of various materials such as graphene, fullerene, carbon-metals, and graphene oxide to the actuator is studied to increase blocking force or improve actuation performances without reducing displacement [11][12][13][14][15][16][25][26][27][28]. Among various proposed additive materials, multiwalled carbon nanotubes (MWCNTs) have shown high chemical and thermal stability, excellent tensile strength and stiffness, and high conductivity and heat resistance. The excellent properties of the MWCNTs improve the mechanical, electrical, and thermal properties of various polymers [29][30][31][32]. The MWCNT was used to increase the blocking force while maintaining the displacement. However, acid treatments are commonly required in the dispersing process; these treatments damage actuators and affect their mechanical properties owing to the resulting CNT structural defects, which are undesirable for further actuator applications [33]. In contrast, Nafion can be used as an alternative to acid treatment to ...

show abstract

“…Cutting CNTs is one of the approaches used for functionalizing nanotubes [8]. As shown in Figure 1, this method of CNTs that might compromise the mechanical integrity of the nanotubes [13]. Long-time sonication has also been reported to cause permanent damage to the nanotubes [14][15][16].…”

Section: Introductionmentioning

confidence: 99%

Dispersion and functionalization of single-walled carbon nanotubes (SWCNTS) for nanocomposite applications

Yaya

Gebremariam²,

Annan

et al. 2016

Matériaux & Techniques

View full text Add to dashboard Cite

We present an easy and reliable method of functionalizing and dispersing single-walled carbon nanotubes (SWCNTs) for nanocomposite production. This was achieved via a mixture of the concentrated acids HNO3/H2SO4, followed by sonication in appropriate solvents (Ethanol, Acetone and/or Dimethylformamide). SWCNTs were functionalized to attach carboxylic moieties on the walls of the nanotubes, which aided in the production of SWCNTs suspensions in acetone, ethanol and dimethylformamide in which nanotubes remained dispersed for a period of two (2) weeks. Energy dispersion analysis (EDS), scanning electron microscopy (SEM) and Raman spectroscopy were used to characterize the functionalized SWCNTs.

show abstract

Novel Ultrasonic Dispersion of Carbon Nanotubes

Abstract: ABSTRACT

Cited by 26 publications

References 10 publications

The Role of Functionalization in the Applications of Carbon Materials: An Overview

The Role of Functionalization in the Applications of Carbon Materials: An Overview

Effect of Ionic Polymer Membrane with Multiwalled Carbon Nanotubes on the Mechanical Performance of Ionic Electroactive Polymer Actuators

Dispersion and functionalization of single-walled carbon nanotubes (SWCNTS) for nanocomposite applications

Contact Info

Product

Resources

About