Conductive polymers having highly enhanced solubility in organic solvent and electrical conductivity and synthesizing process thereof

Abstract

The present invention relates to a new process of synthesizing conductive polymers from monomers substituted with amine group. The process provides simple synthesizing steps for the conductive polymers without using other additives such as stabilizers or emulsifiers. The conductive polymers synthesized according to the present invention have highly enhanced solubility in common organic solvents and electrical conductivity compared to conventional conductive polymers. Therefore, the conductive polymers synthesized according to the present process can be utilized in applications that require high electrical conductivity, for example an electromagnetic interference shield or a transparent electrode of thin film, as well as in specific applications such as various conductive films, fibers, polymer blends, battery electrodes or conductive etch mask layers.

Description

[0001] This application claims the benefits of Korean Patent Application No. 2004-33168, filed on May 11, 2004 in Korea and Korean Patent Application No. 2005-0032461, filed on Apr. 19, 2005, which are herein incorporated by reference for all purposes as if fully set forth herein. BACKGROUND OF THE INVENTION [0002] 1. Field of the Invention [0003] The present invention relates to conductive polymers, and more particularly to conductive polymers which have highly enhanced solubility in organic solvents and electrical conductivity, and synthesizing process thereof. [0004] 2. Discussion of the Related Art [0005] Conductive polymers have conjugated structures along double bonds present in the backbone thereof and has much enhanced electrical conductive properties compared to other organic materials because the conductive polymers form partial electrical charges along the conjugate structures and thereby having unlocalized electrons when the polymers are doped with dopants such as a prot...

AI Technical Summary

Benefits of technology

[0063] The conductive polymer synthesized according to the present invention has highly linear configuration, fewer side chains, and therefore highly improved electrical conductivity compared to polyaniline synthesized according to conventional process. Accordingly, polyaniline of the present invention may be used as various conductive films, fibers, coatings, blends with other polymers, battery electrodes, or mater...

Problems solved by technology

However, the conductive polymers synthesized through the conventional processes, especially the polyaniline as the completely reduced from, leucoemeraldine, the intermediated oxidized from, emeraldine salt, and the fully oxidized form, pernigraniline, have disadvantages that they cannot be made from melting process owing to their high boiling point and that they must experience complex processing steps since they have low solubility in solvents with high-boiling point or universal or compatible solvents such as meta-cresol.

However, those composites have lower electrical conductivity compared to the conductive polymers before reforming.

Especially, the polyaniline synthesized according to the MacDiarmid process has low molecular weight, broad molecular weight distribution, and inferior solubility to solvents or electrical conductivity resulted from side chain reactions to the backbone.

However, since Cao et al. uses functionalized protonic acids as emulsifier, it is difficult to control doping the emulsifier and the process requires commonly expensive material.

Further, since the functionalized organic acid is hardly separated from polyaniline after polymerizing reaction, the conductive polymers may have only very limited uses and highly inferior electrical properties.

However, it is difficult to synthesize polyaniline because the radical initiator in the aqueous layer is separated from the monomer in the organic layer and polyaniline synthesized according to Kinlen process has low electrical conductivity owing to difficulty of control doping process.

However, since pyruvic acid has lower acidity it is difficult to dope polyaniline by pyruvic acid.

However, since it is not easy to separate the non-aqueous layer from an aqueous layer, it is expected that polyaniline synthesized according to Ho process may not have high electrical conductivity.

However, polyaniline film prepared from Palaniappan process has very low electrical conductivity, for example about 0.1 S/cm, and may be only used in much limited applications since it is impossible to raise molecular weight of polyaniline.

However, the synthesized polyaniline has a particle size of about 60˜300 nm, which is affected by the stabilizer, and has low electrical conductivity, which defines its application.

However, since it needs very long polymerization reaction time in ...

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