Abstract

After discovering graphene and its extraordinary intrinsic, other graphene-like nanomaterials (GLNs) became a topic of interest to many scientists of the time. Recently, GLNs, nanosheets of sp2 -hybridized atoms arranged in a two-dimensional lattice with impressive thermal, mechanical, and electrical properties, has attracted both academic and industrial interest because it can produce dramatic improvements in properties at very low filler content. Many studies have been performed on GLNs with various applications, including boron nitride nanosheets, transition metal dichalcogenides, and other two-dimensional (2D) nanomaterials. This rapid advance provides a strong appetence for further research on properties of GLNs, including mechanical, electrical and thermal properties and their potential applications in the nanocomposites industry.

Keywords: graphene-like, nanocomposite, boron nitride, two-dimensional, nanomaterials, polymer

### 1. Introduction

Composite is a combination of at least two components (or phases) that are chemically distinctly different, and these components are not dissolvable. Properties and performance of composites strongly depend on their components. In general, in the composite, there is at least one non-interconnected component, called filler or reinforcement, surrounded by a continuous phase, called matrix [1].

Recently, nanocomposites have attracted a lot of attention. Nanocomposite is actually a composite that at least one of its constituents, typically filler, is in dimensions ranging from 1 to 100 nm. The nanomaterials are incorporated within the matrix for particular purposes such as strength, resistance, electrical conductivity, magnetic properties etc.

A great effort is being made to control nanoscale structures through new approaches. The physical, chemical, and biological properties of nanomaterials are different from the properties of atoms and molecules or even bulk materials. However, the properties of nanocomposites depend not only on the properties of filler and matrix, but also on the morphological and interfacial characteristics of these materials. Nanomaterials have a high surface-to-volume ratio, which makes them ideal for use in nanocomposite materials [2].

There are several categories for composite and nanocomposite classification. One of these categories is based on the type of matrix material. On this basis, there are various composites including [3, 4]:

• Polymer matrix composites (PMCs): In commercial applications, these composites have a high rating compared to other types of composites. Various filler materials can be used in this type of composite. The matrix can be made of thermo-plastic and thermo-set polymers.

electronics to optics [7, 8], sensors [9, 10], biology [11], coating, composite [12, 13]

nanomaterials (GLNs), their properties and application. One of the most important uses of GLNs is the usage as filler in polymer composites due to their unique

The scientists and researchers are encouraged to use other 2D nanomaterials such as boron nitride nanosheets (BNNSs) and metal dichalcogenide nanosheets for producing nanocomposite when observed amazing properties of graphene as reinforcement material for polymer-based composites. Generally, 2D nanomaterials have unique properties for using as reinforcement in nanocomposites, which include: (i) ultrathin 2D nanosheets have high special surface area, (ii) they have high surface-to-volume atomic ratio, therefore are chemically suitable for

functionalizing and so their dispersion improves in polymer matrix. (iii) They have unique mechanical, thermal and electrical characteristics, which make them an

nanotubes (BNNTs), due to the special structure of 2D nanomaterials, contacting or overlapping nanosheets with each other throughout polymeric matrix could form an interconnected network of 2D layers. As a result, the percolation threshold of 2D nanocomposite is lower than other nanocomposites. This means that better properties can be achieved at much lower amounts of reinforcement, which

The other important advantage of the 2D nanosheets is their high surface area, which allows for the proper interaction of filler with polymeric matrix. This interaction results in a dramatic improvement in the properties of the matrix. However, the mentioned properties could be diminished, if the filler is not suitably dispersed or the conditions are created to allow the particles to agglomerate together during the nanocomposite manufacturing. The van der Waals force (vdW) between the layers can lead to agglomeration of nanosheets, which has a negative effect on the properties. On an industrial scale, maintaining the cost of competitive production with a high degree of dispersion and low content of filler is the goal, and therefore the manufacturing processes of these nanocomposites with unique properties that

GLNs are instant and important nanomaterials that have outlandish mechanical and functional properties. Due to their extraordinary properties, these materials have the potential to be recognized as generations of next generation composites with maximum structural and/or functional reinforcement in a minimum amount of filler. Adding these nanomaterials significantly improves the mechanical

properties of the polymer matrix. Thermal, electrical conductivity and dimensional stability of nanocomposite significantly change. In addition, the unique properties

However, the research on GLNs polymer-based nanocomposites is still in its

nanocomposites, such as optical properties, irradiation properties and biocompatibility. The reason is not that these studies are not important or interesting, but rather, the production of GLNs nanocomposite is difficult due to low-yield and high-cost methods to synthesis of GLNs. This prevents the rapid progress of research on properties and application of GLNs polymer-based nanocomposites. In this chapter, we focus on a summary of recent developments in 2D graphenelike nanomaterials in the manufacture of polymer nanocomposites. We have also

of each of these nanosheets will appear in the final nanocomposite.

early stages. Little research has been done on the properties of these

In comparison to the zero-dimensional (0D) nanomaterials such as BN nanoparticles or one-dimensional (1D) nanomaterials, such as boron nitride

the first time, various studies were carried out on a variety of graphene-like

mechanical, electrical and thermal properties.

DOI: http://dx.doi.org/10.5772/intechopen.85513

decreases the cost of composite construction.

have the capacity to scale up is very valuable.

143

ideal candidate for reinforcement of nanocomposites [16].

Since 2004, when a single layer graphene was discovered by Novoselov [14], for

and etc.

Graphene-Like Nanocomposites


The use of polymer composites due to its inherent properties has grown considerably compared to other composites. High strength and modulus, fatigue resistance, high flexibility, multi-functional performance, easy to process, low weight of structure and low cost processing are the features of this category of composites than other composites.

In recent years, two-dimensional (2D) nanomaterials have drawn considerable interest for exploring potential applications. 2D nanomaterials are laminated crystals that exhibit unusual physical-chemical properties in thicknesses of atomic layers (Figure 1). Graphene as a famous member of the family of 2D nanomaterial is a honeycomb network of carbon atoms, co-located with sp<sup>2</sup> hybridize and forming a single graphene atomic layer [5, 6]. Graphene is indubitably one of the most important nanomaterials in the world, which the combination of unique properties in it makes a long way to discover a wide range of applications from

filler materials can be used in this type of composite. The matrix can be made

• Metal matrix composites (MMCs): This category, which is considered an advanced building material, consists of non-metal fillers in a metal matrix. MMCs are mainly used in engineering applications, in cases where the operating temperature is in the range of 250–750°C. Copper, aluminum, titanium and super alloys are widely used to make these composites.

• Ceramic matrix composites (CMCs): This category is considered an advanced building material made of metal/non-metallic fillers in a ceramic matrix. CMCs are used in engineering applications with the operating temperature is in the

The use of polymer composites due to its inherent properties has grown considerably compared to other composites. High strength and modulus, fatigue resistance, high flexibility, multi-functional performance, easy to process, low weight of structure and low cost processing are the features of this category of composites

In recent years, two-dimensional (2D) nanomaterials have drawn considerable interest for exploring potential applications. 2D nanomaterials are laminated crystals that exhibit unusual physical-chemical properties in thicknesses of atomic layers (Figure 1). Graphene as a famous member of the family of 2D nanomaterial is a honeycomb network of carbon atoms, co-located with sp<sup>2</sup> hybridize and forming a single graphene atomic layer [5, 6]. Graphene is indubitably one of the most important nanomaterials in the world, which the combination of unique properties in it makes a long way to discover a wide range of applications from

Schematic view of 2D nanomaterials, a single layer of graphene, boron nitride and transition metal

of thermo-plastic and thermo-set polymers.

range of 800–1650°C.

Nanorods and Nanocomposites

than other composites.

Figure 1.

142

dichalcogenide [15].

electronics to optics [7, 8], sensors [9, 10], biology [11], coating, composite [12, 13] and etc.

Since 2004, when a single layer graphene was discovered by Novoselov [14], for the first time, various studies were carried out on a variety of graphene-like nanomaterials (GLNs), their properties and application. One of the most important uses of GLNs is the usage as filler in polymer composites due to their unique mechanical, electrical and thermal properties.

The scientists and researchers are encouraged to use other 2D nanomaterials such as boron nitride nanosheets (BNNSs) and metal dichalcogenide nanosheets for producing nanocomposite when observed amazing properties of graphene as reinforcement material for polymer-based composites. Generally, 2D nanomaterials have unique properties for using as reinforcement in nanocomposites, which include: (i) ultrathin 2D nanosheets have high special surface area, (ii) they have high surface-to-volume atomic ratio, therefore are chemically suitable for functionalizing and so their dispersion improves in polymer matrix. (iii) They have unique mechanical, thermal and electrical characteristics, which make them an ideal candidate for reinforcement of nanocomposites [16].

In comparison to the zero-dimensional (0D) nanomaterials such as BN nanoparticles or one-dimensional (1D) nanomaterials, such as boron nitride nanotubes (BNNTs), due to the special structure of 2D nanomaterials, contacting or overlapping nanosheets with each other throughout polymeric matrix could form an interconnected network of 2D layers. As a result, the percolation threshold of 2D nanocomposite is lower than other nanocomposites. This means that better properties can be achieved at much lower amounts of reinforcement, which decreases the cost of composite construction.

The other important advantage of the 2D nanosheets is their high surface area, which allows for the proper interaction of filler with polymeric matrix. This interaction results in a dramatic improvement in the properties of the matrix. However, the mentioned properties could be diminished, if the filler is not suitably dispersed or the conditions are created to allow the particles to agglomerate together during the nanocomposite manufacturing. The van der Waals force (vdW) between the layers can lead to agglomeration of nanosheets, which has a negative effect on the properties. On an industrial scale, maintaining the cost of competitive production with a high degree of dispersion and low content of filler is the goal, and therefore the manufacturing processes of these nanocomposites with unique properties that have the capacity to scale up is very valuable.

GLNs are instant and important nanomaterials that have outlandish mechanical and functional properties. Due to their extraordinary properties, these materials have the potential to be recognized as generations of next generation composites with maximum structural and/or functional reinforcement in a minimum amount of filler. Adding these nanomaterials significantly improves the mechanical properties of the polymer matrix. Thermal, electrical conductivity and dimensional stability of nanocomposite significantly change. In addition, the unique properties of each of these nanosheets will appear in the final nanocomposite.

However, the research on GLNs polymer-based nanocomposites is still in its early stages. Little research has been done on the properties of these nanocomposites, such as optical properties, irradiation properties and biocompatibility. The reason is not that these studies are not important or interesting, but rather, the production of GLNs nanocomposite is difficult due to low-yield and high-cost methods to synthesis of GLNs. This prevents the rapid progress of research on properties and application of GLNs polymer-based nanocomposites.

In this chapter, we focus on a summary of recent developments in 2D graphenelike nanomaterials in the manufacture of polymer nanocomposites. We have also

reviewed the synthesis methods of GLNs and the processing polymer-based nanocomposites. Some applications of these nanomaterials have been investigated. Ultimately, we have studied the problems and limitations facing this category of nanocomposites.
