How much do you know about conductive polymer materials?

Compared with traditional conductive materials, conductive polymer materials have many unique properties, such as low density, easy processing, corrosion resistance, structural variability, semiconductors, large-area film formation, and conductivity adjustment over a wide range. It has been widely used in stealth technology, displays, batteries, electronic devices, biomedicine, and sensors.

Classification of conductive polymer materials

According to the structure and the preparation method, the conductive polymer materials can be divided into two types, one is a composite conductive polymer material, and the other is a structural conductive polymer material.

1. Composite conductive polymer material

General polymer materials and various conductive materials, such as graphite, metal powder, metal fiber, metal oxide, carbon black, carbon fiber, through different methods and processing techniques, such as dispersion polymerization, filling compounding, lamination or it is produced by forming a surface electric film. The main varieties are conductive rubber, conductive plastics, conductive fiber fabrics, transparent conductive films, conductive coatings and conductive adhesives. Its properties are related to many aspects of conductive fillers, such as type, particle size, amount, state, and their dispersion in polymeric materials.

2. Structural conductive polymer materials

The structural conductive polymer material refers to a polymer structure itself or a polymer material having a conductive function after being doped. Depending on the type of conductive carriers, structural conductive high molecular polymers can be classified into two types: ionic and electronic; they are classified into polymer semiconductors, polymer metals, and polymer superconductors depending on the conductivity. The ionic conductive polymer is usually called a polymer solid electrolyte, and the carrier during conduction is mainly an ion; the electronic conductive polymer refers to a conductive polymer material mainly composed of a conjugated polymer, and the current carrying current is conductive. Polyaniline, polyacetylene, polypyrrole, polyphenylene acetylene, polyparaphenylene sulfide, etc. all belong to structural conductive polymer materials. Technically speaking, the composite type has a more mature advantage than the structural conductive polymer material, and the structural conductive polymer materials which are the largest and most popular are carbon black filled type and metal filled type.

Application of conductive polymer materials

1. Coloration material

Electrolyticly synthesized conductive polymer materials are accompanied by color changes during electrochemical doping, and can be used as electrochromic devices by utilizing this property. This type of conductive polymer can be electrochemically dedoped and re-doped, and a reversible electrochemical reaction occurs. The electrochemical polymer material can be changed into an insulator by electrochemical doping, and it can be changed into conductor by the oxidative doping. It is a conductor and the conductivity of the material varies with the degree of doping and dedoping. The conductive polymer material can be changed between the conductor, the semiconductor and the insulator by controlling the applied electric quantity, and the optical characteristics of the conductive polymer material also change with the change of the conductivity, according to this characteristic, a conductive polymer material is used as the display material.

This type of electrochromic functional polymer material can also be used as a coating for energy-saving glazing. In the hot summer, it will prevent solar heat from radiating into the interior and the car, keeping the interior cool and comfortable. In addition, such materials are also widely used in display components, instrumentation, etc.

2. Battery

As described above, the conductive polymer has reversible electrochemical redox characteristics, and has the characteristics of small relative density, large room temperature conductivity, and large specific surface area, so that it can be used as an excellent electrode material for batteries. For example, polypyrrole has a high degree of doping and strong stability, and is also very sensitive to changes in electrical information. For example, polypyrrole can be applied to a conventional textile to become an electrical conductor. The secondary battery made of the conductive polymer material has the characteristics of easy production and processing into a film, it is small, light, and high in energy. If the durability of the organic substance and the stability of the organic solvent under high pressure are solved, molecular material-based secondary batteries are likely to be commercialized.

Edited by Suzhou Yacoo Science Co., Ltd.