Authors : P. M. Sabale, A. S. Wadatkar and D. S. Thakare
Page Nos : 139-141
Description :
Polymers are large class of materials consisting of many small molecules that linked together to from longs chains, thus they are known as macromolecules. Polymers are macromolecules, and a sample of a given polymer is characteristically a mixture of molecules with different molecular weight. Polymer made from a single monomer species are called photopolymers whereas those made up of two more different monomer species are copolymers. The repeating atomic grouping, each of which is a monomer residue, is called monomeric units, a large molecule composed of repeat units is called a macromolecule or polymeric chain. Thin films of polymers interesting for many reasons, for instance for packing, coating, material and CD. A polymer blend or polymer mixture is a member of a class of materials analogous to metal alloys, in which at least two polymers are blended together to create a new materials with different Physical properties. Two polymers are generally incompatible as they have very low combinatorial entropy of mixing for the components. This is insufficient to overcome the positive heat of mixing of polymers to make Gibb’s free energy of mixing negative. Only in the presence of specific interaction between two polymers, heat of mixing is negative that makes the free energy of mixing a negative quantity and then the mixing is spontaneous. Both compatible and incompatible blends are industrially important materials. In present research, the blends will be prepared in the laboratory by using different polymer and solvent and obtain the thin film by spin coating and isothermal evaporation technique and study its DC conductivity which useful in the field of insulating electrical and dielectrically application.
Keyword:- DC Conductivity, Spin coating method, Isothermal evaporation technique, Blend
