In the mid 1970s, the first polymer capable of conducting electricity, polyacetylene, was reportedly prepared by accident by Prof. Hideki Shirakawa. The subsequent discovery by Alan Heeger and Alan MacDiarmid that the polymer would undergo an increase in conductivity of 12 orders of magnitude by oxidative doping quickly reverberated around the polymer and electrochemistry communities, and an intensive search for other conducting polymers soon followed. In the late seventies, Alan MacDiarmid, Hideki Shirakawa, and Alan Heeger, along with a group of young students started research in the field of conducting polymers and the ability to dope these polymers over the full range from insulator to metal. This was particularly exciting because it created a new field of research and a number of opportunities. Electronically conducting polymers are extensively conjugated in nature. It is generally agreed that the mechanism of conductivity in these polymers is based on the motion of charged defects within the conjugated framework. Since late seventies, a large number of polymers have been added to the list of conducting polymers such as polypyrrole¬, polythiophene, polyparaphenylene, polyphenylene sulphide, polyaniline, polyphenylene vinylene etc. Conjugated organic polymers are either electrical insulators or semiconductors which can become highly electrically conductive after incorporation of acceptors or donors a process called “doping”. Doping process results in dramatic changes in the electronic, electrical, magnetic, optical and structural properties of the polymer. Doping process is reversible, and it produces the original polymer with little or no degradation of the polymer backbone.
Conducting polymers find application in large variety of areas which is due to their conductivity and redox properties. Some of the interesting application areas are anticorrosion paint, Antistatic , EMI Shielding, RADAR absorbing materials, Catalysis, Supercapacitor, Sensors, Membrane etc. Interest in research on conducting polymers has grown after the 2000 Nobel prize and people found the way to make polymer processible.Conducting polymers are good candidate in different applications for the following reasons -
- ease of fabrication
- low production cost
- easy to interface with electronic devices such as MEMS
- Long life
- High stability
- Environmental friendly
- Easy to dispose
- Tune the polymer according to need
These problem can be overcome by use of conducting polymers such as Polyaniline, Polypyrrole in the thermoplastic itself or as coating on the surface. The use of conducting polymers would provide an effective antistatic material.
Use of conducting blends and composites with conventional polymers as an electrostatic charge dissipative material or antistatic material is one of the promising application of conducting polymers which combines the mechanical properties of conventional polymers and electrical properties of conducting polymers.
Aadarsh Innovations offer conducting polymer based antistatic paint additives as well as plastic masterbatch.
In the present days we are living in the electronic jungle and the effects of electromagnetic interference are becoming more and more pronounced. This is due to the demand for high-speed electronic devices, miniaturization of electronic devices, more use of electronics in computers, in communication equipment, in cars etc.
So there is a need to protect devices against electromagnetic interference (EMI). The effects of EMI can be reduced or diminished by positioning a shielding material between the source of the electromagnetic field and the sensitive device. For a material to act as EMI shielding, it should be electrically conductive. As EMI shielding is composed of reflection and absorption contributions, both the conductivity in the volume of the protecting material as well as the thickness of the material may be of importance. Conducting polymers which are also redox active polymers, such as Polyaniline , polypyrrole, absorbs as well as reflects electromagnetic radiation.