In materials science, 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 material with different physical properties.[1]
During the 1940s, '50s and '60s, the commercial development of new monomers for production of new polymers seemed endless. In this period, it was discovered that the development of the new techniques for the modification of the already existing polymers, would be economically viable.
The first technique of modification developed was the polymerization, in other words, the joint polymerization of more than one kind of polymer.
A new polymers modification process, based on a simple mechanical mixture of two polymers first appeared when Thomas Hancock created a mixture of natural rubber with gutta-percha. This process generated a new polymer class called "polymer blends."
Polymer blends can be broadly divided into three categories:
The use of the term polymer alloy for a polymer blend is discouraged, as the former term includes multiphase copolymers but excludes incompatible polymer blends.
Examples of miscible polymer blends:
Polymer blends can be used as thermoplastic elastomers.