Polymers are generally known for their insulating property.
But 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 the late seventies, a large number of polymers have been added to the list of conducting polymers such as polypyrrole, polythiophene, poly para phenylene, polyphenylene sulphide, polyaniline, polyphenylene vinylene, etc.
Conjugated organic polymers are either electrical insulators or semiconductors that can become highly electrically conductive after incorporation of acceptors or donors a process called “doping”. The doping process results in dramatic changes in the electronic, electrical, magnetic, optical, and structural properties of the polymer. The doping process is reversible, and it produces the original polymer with little or no degradation of the polymer backbone.
Conducting polymers find application in a 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 a way to make polymer processible.
Conducting polymers are a 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
The continuously growing interest in the study of PAni over the years is mainly because of it’s diverse, but unique properties of PANI, allowing its potential applications in various fields. Among all the conducting polymers, polyaniline is known for its (i) ease of synthesis (ii) environmental stability, and (iii) easy to dope. Aadarsh Innovations offers different types of conducting Polyaniline (Emeraldine Salt, doped with different dopants), Polyaniline EB (Emeraldine Base / Reduced state / Undoped state / Nonconducting state), custom synthesized Polyaniline, etc.
Electrically Conducting polymers such as Polyaniline, Polypyrrole, Polythiophene etc. have been studied extensively and a very intensive effort has been made in the recent decades for their anticorrosion behavior which is due to another interesting property shown by the material apart from conductivity that is the redox property of the material. The motivation for the development of the new anticorrosive coating system is due to the desires of the world community to replace chromium(VI)-containing corrosion resistant coating systems for iron and different alloys. Chromates, with its VI oxidation state compound, is the most effective universal corrosion inhibitor, but its use is banned in many countries across the world due to its hazardous and toxic effect on the environment and carcinogenic effect on humans. Coatings based on Conducting polymer polyaniline, polypyrrole, etc. The self-healing property of paint containing conducting polymer is subject of interest which may be due to the triggered release of dopant in the scratched area. The triggered release of dopant may be due to the difference in energy level in the paint and the exposed steel surface. . as pigments have been found to be promising replacements for Cr(VI)-containing coatings. Conducting polymers based “smart” coatings can prevent corrosion even in scratched areas where bare steel surface is exposed to the aggressive environment, which is known as self-healing property of conducting polymer.
Electromagnetic interference (EMI) occurs when sensitive electronic devices receive electromagnetic radiation emitted by other nearby electric or electronic devices such as microwaves, wireless computers, radios, and mobile phones. The affected devices may malfunction or fail as a result of electromagnetic interference. One of the examples of malfunctioning of devices due to EMI is the malfunctioning of pacemakers in the vicinity of certain electronic devices.
In the present day, 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, communication equipment, 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 reflect electromagnetic radiation.
Among known conducting polymers, polypyrrole is most frequently used in commercial applications due to the high conductivity, long term stability of its conductivity, and the possibility of forming homopolymers or composites with optimal mechanical properties. It is knows for its stability in the oxidized state and interesting redox properties. Aadarsh Innovations offers different types of conducting Polypyrrole, Polypyrrole in Undoped state / Nonconducting state, custom synthesized Polypyrrole etc.
Electrostatic charge dissipation is one of the most important issues which causes problems while handling sensitive electronic components, explosive chemicals, or dry powders. The use of antistatic materials reduces ESD related problems or the amount of damage caused to the products in an assembly line. Antistatic protection is required in textile machine parts, rollers, weaving machine arms, airplane tires electronic industry, etc. Conventional polymers which are used for packaging of various electronic equipment, due to their insulating nature, these polymers failed to dissipate the static or electrostatic charge. The generation of static electricity on the materials leads to a variety of problems in manufacturing and consumer use. Electronic components are susceptible to damage from electrostatic discharge.
These problems can be overcome by the use of conducting polymers such as Polyaniline, Polypyrrole in the thermoplastic itself, or as a coating on the surface. The use of conducting polymers would provide effective antistatic material.
The 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 to conduct polymer-based antistatic paint additives as well as a plastic masterbatch.
RADAR Absorbing Material
Conducting polymers such as Polyaniline, Polypyrroles can be used in RADAR absorbing coating system also.
Please visit Aonomy Speciality Polymers Pvt. Ltd for further information about electrically conductive polymer-based products.