Introduction of Polymer Nanocomposites

Abstract

Polymers have been one of the most important components in almost every area of human activity today. Nowadays, polymers as multifunctional materials gradually replace metals, glass, paper, and other traditional materials in various applications due to its lightweight, flexibility, and low cost [1]. In most of their applications, the applied materials are not composed of a single chemical component but mixture systems of multiple components with polymers and other additives. By incorporating different additives, such as metal, minerals, or even air, a wide variety of materials with unique physical properties and competitive production costs can be produced. For example, glass fiber-reinforced plastics are composite materials manufactured by laminating unsaturated polyester resin with glass fiber and filler, which can increase mechanical strength and heat resistance [2]. In addition, scientific research shows that the size of filling material in fiber reinforced composites has a great influence on the material properties, since the size of the filling particles largely determines the surface interactions of adhesion, particle movement, dispersion, and bonding between the surface and matrix [3]. With the particle size of the filler that gradually reduces to the nanoscale, some properties depending on the interface have undergone great changes, such as gas adsorption, chemical activity, electrical properties, and catalytic activity. Examples of different sizes of materials are shown in Figure 1.1, and a hydrogen atom is about 0.1 nm in size, while a human hair is 104 nm in diameter. Among them, nanomaterials are employed to describe the materials that have at least one dimension in the size range from approximately 1 to 100 nm [4]. Different from the bulk and microscale materials, nanomaterials are unique in that they have many unusual, useful, and interesting properties. For example, bulk gold is a very stable precious metal in golden color, which can be kept for a long time under atmospheric environment, so it is used as the initial currency by people. Unlike bulk gold, gold nanoparticles dispersed in water will show different colors according to the size of nanoparticles,