WO1996014642A1

WO1996014642A1 - Semiconducting polymers and methods for the production of these

Info

Publication number: WO1996014642A1
Application number: PCT/DK1995/000435
Authority: WO
Inventors: Anders Ravn SØRENSEN; Anders Nielsen
Original assignee: Nkt Research Center A/S
Priority date: 1994-11-04
Filing date: 1995-11-02
Publication date: 1996-05-17

Abstract

A novel type of semiconducting polymer comprising an insulating thermoplastic polymer carrier and an intrinsically conducting polymer (ICP) is disclosed. In this semiconducting polymer essentially each of the ICP mesomers are covalently linked to the carrier, and the content of ICP is 0,5 to 25 % by weight, preferably 1 to 15 % by weight, more preferably 3 to 10 % by weight. The new semiconducting polymer is a material having good mechanical properties (e.g. mechanical properties comparable to well known thermplastics like polyethylen, poly(meth)acrylates, EVA, etc.) and it shows a loss of conductivity during processing which is lower than the conductivity loss of known semiconducting polymer materials. The semiconducting polymer is suitable for use as antistatic coating or EMI-shielding.

Description

Semiconducting polymers and methods for the production of these.

The present invention relates to semiconducting polymers and to methods for the production of these.

In the present context a semiconductor is defined as a material having a conductivity in the range 10^"9 to 10³ S/cm (cf. Ashcroft and Mermin, Solid State Physics, 1976, p. 562).

ICP's have been known since the late 1970's. The majority of the known ICP's contain a (poly)-conjugated p-electron system. Examples of these polymers are polyacetylene (PA), polyparaphenylenevinylene (PPV), polyaniline (PAni), poly- thiophene (PT), and polypyrrole (PPy). Besides said polymers a range of derivatives thereof have been made, e.g. poly-3- alkylthiophene. In their basic form they are all insulators but upon oxidation or reduction of the p-electron system they become conducting. In the case of oxidation p-type conductors are formed whereas reduction leads to n-type conductors. By the oxidation of the polymers they are converted into polymer radical cations. This process is often referred to as "doping" and can be done chemically using electron acceptors like FeCl₃ or I₂ or it can be done electrochemically. The doping process requires, that at the same time anions are incorporated in the structure in order to keep electro- neutrality. The anions can be either those anions formed by the reduction of the oxidizing agent or it can be anions intentionally added to the reaction medium, typically organic sulphonates.

When the polymers are formed by electrochemical oxidation of e.g. pyrrole, thin films are made whereas chemical oxidation using e.g. FeCl₃ gives powdery materials. Only the latter process is suitable for production of materials in bulk amounts. In general the conductivity achieved for films lies in the range of 50-100 S/cm, and for bulk materials in powder form the conductivity measured on pressed pellets lies some order of magnitude lower, e.g. 0,1-1 S/cm.

Despite their relatively good conductivity only a few applications for the bulk materials have been realized although potential uses like antistatic coatings, EMI- shielding, semiconductors in cables and the like may be foreseen. One major obstacle to successful application of most of the above mentioned polymers is their lack of chemical stability even under normal environmental conditions (see e.g. Synth. Met., vol 51 (1992), pp. 287-297). Besides this also in some cases insufficient thermal stability can prevent their use. Only polyaniline and polypyrrole can be considered sufficiently stable in their conducting form to be of commercial interest. PAni because it can be made conduct¬ ing by protonation and polypyrrole because the oxidation potential of this polymer is rather low (app. - 0.2 V vs. SCE).

Besides chemical stability a prerequisite for successful commercial applications of these polymers is that they posses mechanical properties that allow processing them by conven¬ tional techniques like e.g. extrusion and injection moulding. The mechanical properties of the ICP's are in general not sufficient in order to fulfil such demands, and consequently the ICP's must be modified so that improved processability can be achieved or alternatively new methods of making processible composite materials must be developed.

Various approaches have been taken in order to develop materials having better processability. These include improving the polymers mechanical properties by the introduc¬ tion of substituents or by other chemical structure modifica¬ tions at monomer level. Alternatively development of methods for producing composite materials comprising a conducting filler and a non-conducting matrix polymer have been investi¬ gated. For polypyrrole the chemical structure modification mentioned above have not led any to commercial attractive polymers. In particular it should be mentioned that the easily accessible poly-N-alkylpyrroles have low conductivity and the synthesis of e.g. 3-alkylpyrroles is rather lengthy.

Development of the soluble poly-3-(alkylthiophenes) with good mechanical properties and blendable with e.g. polyethylene is an example of another strategy. The poor chemical stability of polythiophene and poly-3-alkylthiophene however prevents commercial applications of thiophene based materials.

J. Chem. Soc, Chem. Commun. 1985, pp. 375-376 describes production of pyrrole-styrene films by electrochemical poly¬ merization of pyrrole into a polymer matrix of polystyrene. The obtained products contain large amounts of ICP (50 to 95 % by weight).

The majority of composite materials produced is based on carbon black filled materials or materials with metal flakes or metal fibres, i.e. a particulate conducting filler moulded into a thermoplast to give a semiconducting compound. In this way it is possible to produce composites having conductiv- ities in the range 0,01-1 S/cm. Similar methods can be used also for ICP-powders, but the use of particulate materials also has some serious drawbacks:

For spherical particles the lowest amount of conductive addi- tive to provide conductivity - the percolation threshold - can be calculated to be 16 vol. %. At this volume fraction of conducting material the individual particles start to touch each other and make the formation of conducting paths in the material possible. This implies the following behaviour with respect to the conductivity of the material. At volume frac¬ tions below the percolation threshold the conductivity of the material will be very low, almost like that of the insulating matrix polymer. Right at the percolation threshold the conductivity will increase very steeply and at filler contents 5-10 % above the percolation threshold the conduc¬ tivity will be almost as high as that of the filler material. For practical applications an even higher amount (25-30%) of filler must be used owing to agglomeration of the particles and in order to avoid loss of conductivity if the temperature of the composite increases during use causing the matrix polymer to expand and thereby breaking the conducting pathways in the material.

Therefore a need exists for improving the presently available ICP based conductive polymer materials. Furthermore it is desirable to substitute conventional carbon black based composites in electric installations, cables and other devices, where the presence of semiconductive matter is crucial for the performance of the given product and where good processability is an important point in order to achieve reasonable production rates in e.g. continuous cable or tube extrusion processes or in batch-wise injection moulding etc.

It is an object of the present invention to provide se¬ miconducting polymer materials having good mechanical properties (e.g. mechanical properties comparable to well known thermoplastics like polyethylen, poly(meth)acrylates, EVA etc. ) and which show a loss of conductivity during processing which is lower than the conductivity loss of known semiconducting polymer materials.

It is another object of the invention to provide semicon¬ ducting polymer materials which are less expensive than known semiconducting polymer materials.

According to the invention these objects are accomplished by a semiconducting polymer comprising:

- an insulating thermoplastic polymer carrier, and - an intrinsically conducting polymer (ICP),

and characterized in that essentially each of the ICP mesomers are covalently linked to the carrier, and that the content of ICP is from 0,5 to 25% by weight, preferably 1 to 15% by weight, most preferably 3 to 10% by weight.

In the present context an insulating material is defined as a material having an electrical conductivity lower than 10^"1 S/cm, and a mesomer is defined as a polymeric or oligomeric molecule consisting of at least 4 monomeric units. The term "mesomer" refers to an indvidual molecule of a polymer material.

It is very surprising and unforeseen that a product according to the invention has a higher conductivity than a composite product consisting of a physical mixture of the corresponding amounts of thermoplastic polymer and ICP.

The electrical conductivity of the semiconducting polymer according to the invention can be adjusted by varying the content of ICP. Increasing the ICP content of the product results in an increase in electrical conductivity.

ICP mesomers are preferably linked covalently to the carrier through an optionally substituted alkylene or oxyalkylene group. The chain length of said alkylene or oxyalkylene group should be so large that the conductivity and the stability of the product of the invention is not affected by sterical hindrance between the carrier and the ICP-mesomers. Accord¬ ingly, a chain length of least 2 carbon atoms is preferred. In general the upper limit of the chain length is not critical. On the other hand the chain length should be so low that no phase separation of thermoplastic carrier and ICP in the product occurs. Accordingly, a chain length of 2 to 20 carbon atoms is suitable and a chain length of 2 to 10 carbon atoms is preferred.

The above-mentioned alkylene or oxyalkylene group linking ICP-mesomers to the thermoplastic carrier optionally contains one or more of the following substituents: alkyl, alkoxy, hydroxy, nitro, cyano, carboxylic acid and carboxylic acid ester groups. In order to avoid sterical hindrance, carbon atoms in the alkylene or oxyalkylene group which are covalently bonded directly to the carrier or an ICP mesomer are preferably unsubstituted.

Alkylene groups suitable for linking ICP-mesomers covalently to the carrier are for example: -CH₂CH₂-, -(CH₂)₄-, -(CH₂)₅-, - (CH₂)₆-, -(CH₂)₇-, -(CH₂)₈- and -(CH₂)₁₀-.

Oxyalkylene groups suitable for linking ICP-mesomers covalently to the carrier are for example: -CH₂CH₂0-, (CH₂CH₂0)₂-, -(CH₂CH₂0)₄-, -(CH₂CH₂0)₅-, -(CH₂CH₂0)₆-, -(CH₂CH₂0)₇- , -(CH₂CH₂0)₈- and -(CH₂CH₂0)₁₀-.

Substituted alkylene groups suitable for linking ICP-mesomers covalently to the carrier are for example alkyl substituted alkylene groups such as -CH₂CH(CH₃)CH₂- and -(CH₂)₄CH(CH₃)- (CH₂)₃- or hydroxy substituted alkylene groups such as - (CH₂)₄CH(0H)(CH₂)₃-.

The thermoplastic polymer carrier is advantageously a linear or slightly branched homopolymer or statistical copolymer based on 10-100.000 monomeric units.

Preferably the thermoplastic polymer carrier is selected from the group consisting of polyolefins, EPDM and EPDM-like elastomers, EVA copolymers, propylene-hexadiene copolymers, styrene-maleic acid copolymers, and ABS or ABS-like copolymers. In general the exact choice of thermoplastic polymer carrier depends on the required properties of the end product such as thermoplastic and mechanical properties and/or chemical and thermal stability. In case of flexible devices, cables, etc. the polymer carrier is advantageously selected among extru- dable polymers such as polyolefins, EPDM and EPDM-like elastomers, EVA copolymers and propylene-hexadiene copolymers. In case of rigid products such as housings, cabinets, etc. the polymer carrier is advantageously selected among injection mouldable polymers such as styrene-maleic acid copolymers and ABS or ABS-like copolymers.

ICP-forming monomers are preferably selected from optionally substituted, preferably five-membered, aromatic or hetero- aromatic compounds. ICP-forming monomers are more preferably selected from optionally substituted thiophene and pyrrole.

Suitable substituents for the ICP-forming monomers are those which are stable under oxidative conditions. In particular the following groups are suitable substituents: alkyl groups such as methyl and ethyl, alkoxy groups such as methoxy and ethoxy, and thioalkyl groups such as thiomethyl and thio- ethyl.

Preferably ICP-mesomers are distributed homogeneously throughout the polymer carrier.

It is another object of the invention to provide a simple and economical method for the production in bulk amounts of semi- conducting polymers according to the invention.

According to the invention this object is accomplished by a method comprising:

a) reacting a thermoplastic polymer carrier with anchoring molecules containing a functional group capable of forming a covalent bond to the carrier and an electrochemically active moiety capable of serving as an initiating species in the polymerisation of ICP-forming monomers, and

b) reacting the product obtained in step a) with ICP-forming monomers in the presence of an oxidation agent.

In step a) the anchoring molecule functional groups react with functionalities in the polymer carrier resulting in the formation of covalent bonds linking the anchoring molecules to the carrier. Anchoring molecule functional groups and polymer carrier functionalities should be selected so that the covalent bonds formed in step a) are stable, especially under thermal and hydrolytic conditions. Stable covalent bonds are for example imide, ether and C-C bonds.

Imide bonds are e.g. formed when the anchoring molecules contain a primary amine functional group and the carrier contains maleic anhydride functionalities or vice versa. The formation of imide bonds generally proceeds according to the following reaction scheme:

Ether bonds are e.g. formed when the anchoring molecules contain a functional halogen atom and the carrier contains hydroxyl functionalities or vice versa. In this case the reaction performed in step a) is normally referred to as an alkylation reaction. Bromine is the preferred functional halogen atom. Alkylation reactions generally proceed accord- ing to the following reaction scheme: R -Br + R O H R -O -R

C-C bonds are e.g. formed when the anchoring molecules contain a (meth)acryl group and the carrier contains a ketene acetal anion or vice versa. In this case the reaction performed in step a) is normally referred to as an "endcap- ping" reaction which may proceed according to the following reaction scheme:

In step b) the electroactive moieties are oxidized by the oxidation agent, thus enabling these to serve as initiating species for the polymerisation of the ICP-forming polymers. The process performed in step b) is normally referred to as a "grafting" process.

The oxidation agent must have an oxidation potential suffi- cient to oxidize the electroactive moieties. Preferred oxida¬ tion agents are anhydrous ferric chloride or its hexahydrate.

The difference in oxidation potential between the ICP-forming monomers (E_py) and the electrochemical active moieties (E_pB) can suitably be matched according to the following prin¬ ciples: The oxidation potential of the electroactive species should be lower than the oxidation potential of the ICP- forming monomers so as to ensure that the electroactive species actually take part in the oxidation reaction. If on the other hand the oxidation potential of the electrochemi- cally active moieties is too low in comparison with the oxidation potential of the ICP-forming monomers, electro- active species will start reacting with other electroactive moieties.

Preferably the difference E_py - E_pB is in the range ]0,0 V;0,8 V], more preferably in the range [0,1 V;0,4 V] .

The electrochemically active moiety generally consists of at least 2, preferably 2 to 10, more preferably 2 or 3 five- membered heterocyclic compounds.

Suitable electroactive moieties are for example:

2,2' -bipyrrole, 2,2' -bithiophene, 2-pyrrolo-2' -thiophene, α- terthiophene, α-terpyrrole, 2-(2-pyrrolo)-5-(2-thienyl)- pyrrole, aniline.

In particular electroactive moieties consisting of thiophene or pyrrole units connected through α,α-linkages are pre¬ ferred. The most preferred electroactive moiety is 2,5-di-(2- thienyl)-pyrrole (SNS) .

Being an anchoring molecule constituent the electroactive moiety always contains a substituent representing the comple¬ mentary part of the anchoring molecule.

Apart form the substituent representing the complementary part of the anchoring molecule, the electroactive moiety may contain one or more of the following substituents: alkyl, alkoxy, thioalkyl, hydroxyl, nitro, cyano, carboxylic acid and carboxylic acid ester groups.

The selected substituents should be stable under oxidative conditions and have no severe effect on the p-electron system of the electroactive moiety. The following molecules are typical examples of anchoring molecules:

In the above formulae, R represents an alkylene or oxy¬ alkylene group.

To balance the positive charge of the oxidized ICP several types of organic or inorganic anions can be used. These may include chloride, benzene sulphonic, p-toluene sulphonic, p- dodecyl sulphonic, poly(ethylene oxide) anions.

Preferably ICP-forming monomers are added in an amount of 0,5 to 25% by weight, more preferably 1 to 15% by weight, in particular 3 to 10% by weight.

In a preferred embodiment the method according to the invention comprises:

a) dissolving the thermoplastic polymer carrier, anchoring molecules and optionally an organic or inorganic acid in a solvent and refluxing the resulting solution for 1-48 hours,

b) recovering the product obtained in step a) by precipita¬ tion in a non-solvent followed by washing,

c) dissolving the product obtained in step b), ICP-forming monomers, a . chemical oxidation agent and optionally a compound capable of forming counter-ions to oxidized ICP in a solvent, and stirring the solution for 1-24 hours at 0 to 50°C, d) recovering of the product formed in step c) by precipita¬ tion in a non-solvent followed by washing and drying.

In the following the invention is further illustrated with reference to the drawings, in which:

Fig. 1. schematically shows a) the reaction between a polymer carrier A containing the functionalities F₁ and anchoring molecules B-X-F₂ wherein F₂ is a functional group capable of reacting with F-_^ resulting in the formation of a covalent bond, B is an electroactive species capable of serving as an initiating species under polymerization conditions, and X is a molecular fragment connecting F₂ and B, and b) the reaction between the product thus formed and ICP-forming monomers c resulting in the formation of ICP mesomers C covalently bonded to the polymer carrier through the molecular fragment X;

Fig. 2 schematically shows the the second step of the reaction in Fig. 1 where the molecular fragment is an ( -CH₂- )_n alkylene group, the electroactive moiety B is SNS and the ICP-forming monomers are pyrrole monomers.

In the following Example I preparation of anchoring molecules is illustrated.

EXAMPLE I.

Preparation of l-(4-aminobutyl)-2, 5-di-(2-thienyl)-pyrrole.

A mixture consisting of 5.0 g (20 mmol) of l,4-bis-(2- thienyl)-butane-l,4-dion, 10 ml (100 mmol) of 1,4-diamino- butane and 1 ml of acetic acid in 75 ml of toluene was refluxed in a Dean Stark apparatus under N₂ for 24 h. The cooled mixture was washed with 2x50 ml of water, the organic phase evaporated until dry and then dissolved in 50 ml of diethylether and the product precipitated with 1.6 ml of cone. HCl. The crystals were suspended in a small amount of water and stirred at 0°C for 30 min. then filtered and dried. 5.45 g (80.5%) of the hydrochloride of the title compound was obtained.

MR₆₀ (CDC1₃): d H (free base form) 7.4-6.95 6H (m); 6.25 2H

(s) 4.15 2H (t, J=7 Hz.); 2.4 2H (t, J=7 Hz); 1.8-0.8 4H

(m); 1.05 2H (s,broad). Mass spectrometry of the base: 30 (38), 72 (21), 231 (100), 232 (17), 302 (37).

In the following examples II to VI preparation of semicon¬ ducting polymers according to the invention is illustrated.

Conductivity measurements were carried out according to British Standard no. 2044.

EXAMPLE II.

50 g of a copolymer based on 91% by weight ethylene, 7% by weight alkyl acrylate and 2 % by weight maleic anhydride MAH (Lotader 3200, Elf Atochem) was mixed with 1.0 g of SNS- C₈H₁₆NH₂, 0.5g acetic acid, 200ml toluene. The resulting mixture was refluxed for 24 hours with stirring. The product was precipitated from methanol and washed several times with ethanol. After drying in a vacuum oven overnight, the product was analyzed using Gel Permeation Chromatography in conjunc¬ tion with RI- and UV-detectors, which proved the presence of SNS-units in the high molecular weight regions, thus demon¬ strating the reactivity of the MAH functions in the copolymer towards amine-functional anchoring molecules. 5.0 g of the product was redissolved in 50 ml warm chloroform, 0.1 g pyrrole and 4.0g p-toluene sulfonic acid sodium salt was added to the solution, and the reaction flask was emerged into a water bath at 20°C during stirring. 0.15 g pyrrole in 25 ml chloroform and anhydrous ferric chloride in 0.2 M chloroform solution was added slowly during vigorous stir¬ ring. The reaction mixture was left for 12 hours with stirring. The resulting slurry was precipitated in methanol and washed until neutral reaction with methanol and water. After drying in vacuum oven at 40°C, a sheet of the product was pressed at a pressure of 20 bar and a temperature of 130°C for 30 seconds. The conductivity was measured with a four-point device to be 0.005-0.01 S/cm.

EXAMPLE III.

50 g of a copolymer based on 91 % by weight ethylene, 7 % by weight alkyl acrylate and 2 % by weight maleic anhydride MAH (Lotader 3200, Elf Atochem) was mixed with 1.0 g of SNS- C₈H_α6NH₂, 0.5g acetic acid, 200ml toluene and the mixture was refluxed for 24 hours with stirring. The product was subsequently treated as described in example II., but with the exception that a total of 1.0 g of pyrrole was oxidized with 7.0 g benzene sulfonic acid sodium salt. After drying in vacuum oven at 40°C, a sheet of the product was pressed at a pressure of 20 bar and a temperature of 130°C for 30 seconds. The conductivity was measured with a four-point device to be 0.12 S/cm.

EXAMPLE IV.

50 g of a copolymer based on 73% by weight ethylene, 26.5% by weight vinyl acetate (Lotader 6600, Elf Atochem) and 0.5% by weight maleic anhydride MAH was mixed with 1.0 g SNS-C₈H₁₆NH₂, l.Og acetic acid, 150ml toluene and the resulting mixture was refluxed for 24 hours with stirring. The product was poured into a 95/5 vol% methanol/water mixture and the precipitates were treated as described in example II, however after the polymerization with pyrrole in chloroform and drying in vacuum oven, the product was pressed at 20 bars and 125°C for 50 seconds. The conductivity was measured with a four-point device to be < 10^"7 S/cm.

EXAMPLE V. A linear poly(butyl methacrylate) PBMA chain possessing low polydispersity and containing butyl lithium ketene acetal endgroup was prepared by living anionic polymerization techniques (see e.g. G. Odian, Principles of Polymerization, John Wiley & Sons, New York, 1981) in tetrahydrofuran at temperatures below -65°C. The target molecular weights were approximately 5.000 g/mole, based on the ratio between monomer and initiating anions. To this solution was added 1.05-1,5 equivalent methacryloxy octyl-SNS relative to living poly(butyl methacrylate) chains and finally methanol was added. The resulting octyl-SNS functional PBMA was isolated by precipitation from methanol and characterized by Gel Permeation Chromatography in conjunction with RI- and UV- detectors, which provided evidence for the presence of SNS- units in the polymer. 10 g of the polymer was redissolved in 50 ml chloroform under stirring at room temperature, and 0.2 g pyrrole was added together with 1.1 g p-toluene sulfonic acid sodium salt. 0.8 g pyrrole in 25 ml chloroform was then added dropwise simultaneously with 0.2 M ferric chloride in chloroform in a period of 30 minutes. After 12 hours the product was isolated by pouring the resulting slurry into methanol. After drying in vacuum oven, a sheet was pressed at 20 bar and 130°C for 30 seconds. The conductivity of the product was measured to 0.01-0.05 S/cm by the four-probe method.

EXAMPLE VI. Based on 50 w/w% methyl methacrylate and 50 w/w% 2-ethyl hexyl methacrylate, a linear poly-co(alkyl methacrylate) chain possessing low polydispersity and containing alkyl lithium ketene acetal endgroups was prepared by living anionic polymerization techniques in tetrahydrofuran at temperatures below -65°C. From the ratio between monomer and initiating anionic species the theoretical average molecular weight was estimated to 10000 g/mole. The presence of SNS- units in the polymer is confirmed by GPC in connection with RI- and UV-detectors. 5.0 g of this product was dissolved in 50 ml chloroform, and 0,1 g pyrrole, 0.56 g benzene sulfonic acid sodium salt was added. Oxidation of pyrrole took place simultaneously with the addition of 0.4 g pyrrole in 10 ml chloroform and 0,2 M ferric chloride in chloroform during stirring. A slurry resulted from which the precipitate was isolated and washed with water until neutral reaction, and dried until constant weight. The conductivity of a pressed sheet was measured to 1.5 10^" S/cm.

Claims

1. A semiconducting polymer comprising:

- an insulating thermoplastic polymer carrier, and

- an intrinsically conducting polymer (ICP),

c h a r a c t e r i z e d in that essentially each of the ICP mesomers are covalently linked to the carrier, and that the content of ICP is 0,5 to 25% by weight, preferably 1 to 15% by weight, more preferably 3 to 10% by weight.

2. A semiconducting polymer according to claim 1, c h a r a c t e r i z e d in that essentiallly each of the ICP mesomers are covalently linked to the carrier through an optionally substituted alkylene or oxyalkylene group having a chain length of at least 2 carbon atoms, preferably 2 to 20 carbon atoms, more preferably 2 to 10 carbon atoms.

3. A semiconducting polymer according to claim 1 or 2, c h a r a c t e r i z e d in that the thermoplastic polymer carrier is selected from the group consisting of polyolefins, EPDM and EPDM-like elastomers, EVA copolymers, propylene- hexadiene copolymers, styrene-maleic acid copolymers, and ABS and ABS-like copolymers.

4. A semiconducting polymer according to claims 1 to 3, c h a r a c t e r i z e d in that the ICP-forming monomers are selected from optionally substituted, preferably five-membe- red, aromatic and heteroaromatic compounds.

5. A semiconducting polymer according to claim 4, c h a r a c t e r i z e d in that the ICP-forming monomers are selected from optionally substituted thiophene and pyrrole.

6. A method for the production of a semiconducting polymer according to claims 1 to 5, c h a r a c t e r i z e d in that it comprises:

7. A method for the production of a semiconducting polymer according to claim 6, c h a r a c t e r i z e d in that it comprises:

a) dissolving the thermoplastic polymer carrier, anchoring molecules and optionally an organic or inorganic acid in a solvent and refluxing the resulting solution for 1 to 48 hours,

c) dissolving the product obtained in step b), ICP-forming monomers, a chemical oxidation agent and optionally a compound capable of forming counter-ions to oxidized ICP in a solvent, and leaving the solution for 1 to 24 hours at 0 to 50 °C,

d) recovering of the product formed in step c) by precipita¬ tion in a non-solvent followed by washing and drying.

8. A method for the production of a semiconducting polymer according to claim 6 or 7, c h a r a c t e r i z e d in that 0,0 V < E_py - E_pB < 0,8 V

wherein E_py represents the oxidation potential of an ICP- forming monomer and E_pB represents the oxidation potential of the electrochemically active moiety in the anchoring molecules.

9. A method for the production of a semiconducting polymer according to claims 6 to 8, c h a r a c t e r i z e d in that the electrochemically active moiety consists of at least 2, preferably 2 to 10, more preferably 2 or 3 optionally substituted five-membered heterocyclic rings connected through α,α-linkages.

10. A method for the production of a semiconducting polymer according to claim 9, c h a r a c t e r i z e d in that the electrochemically active moiety is selected from optionally substituted thiophene and pyrrole.

11. A method for the production of a semiconducting polymer according to claim 10, c h a r a c t e r i z e d in that the electrochemically active moiety is 2,5-di-(2-thienyl)- pyrrole.

12. Use of a semiconducting polymer according to claims 1 to 5 as antistatic coating or EMI-shielding.