ABSTRACT
The basic structures and characteristics of polymers and plastics are attributable to five main factors such as arrangement, chemical structure, degree of polymerization (size), form, and polymerization method [1,2]. Polymers are composed of recurring monomer units that are essentially organic in nature and are bonded chemically during polymerization. Predominantly, polymers and plastics comprise of the elements carbon (C), hydrogen (H), nitrogen (N), bromine (Br), chlorine (Cl), fluorine (F), oxygen (O), silicon (Si), and sulfur (S). Also, as discussed under Chapter 2, it is typical to fortify polymers with additives. Additives in general, and functional additives in particular are additional sources of chemical bonding in polymers and plastics [3-6]. Popular and currently in-use functional additives include nanomaterials such as nanoclay, carbon nanotubes, carbon nanofibers, nanographenes, etc., powdered metals, metal fibers, compatibilizers, coupling agents, polyhedral oligomeric silsesquioxane (POSS), nanosilica, nanotitanium dioxide, and others [7-10]. Coupling agents and compatibilizers are considered similar but are distinguished by their medium of action. Compatibilizers facilitate adhesion between two immiscible polymers by reducing their interfacial tension, whereas coupling agents accomplish this between a polymer and filler. Carbon nanotubes, carbon nanofibers, nanographenes [11,12], graphite, carbon black, powdered metals, and metal fibers are known for their electrical conductivity properties. Chemical bonding in polymers and plastics are further affirmed by some of their inherent adhesive characteristics. In fuse bonding, melting of two, in-contact polymers results in chemical bonding of their molecules and atoms to form essentially one single material. A similar process occurs with solvent-based adhesives; the solvent is able to dissolve and solubilize both materials, and the solvent’s evaporation brings molecules of the materials together to form chemical bonds of a single material. These chemical-type bondings are distinct from the interlocking, mechanical type.
