WO1993026012A1 - Procede d'impregnation d'un substrat en continu par un polymere conducteur electronique - Google Patents
Procede d'impregnation d'un substrat en continu par un polymere conducteur electronique Download PDFInfo
- Publication number
- WO1993026012A1 WO1993026012A1 PCT/FR1993/000528 FR9300528W WO9326012A1 WO 1993026012 A1 WO1993026012 A1 WO 1993026012A1 FR 9300528 W FR9300528 W FR 9300528W WO 9326012 A1 WO9326012 A1 WO 9326012A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- substrate
- solution
- oxidant
- acid
- monomer
- Prior art date
Links
Classifications
-
- D—TEXTILES; PAPER
- D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
- D06M—TREATMENT, NOT PROVIDED FOR ELSEWHERE IN CLASS D06, OF FIBRES, THREADS, YARNS, FABRICS, FEATHERS OR FIBROUS GOODS MADE FROM SUCH MATERIALS
- D06M15/00—Treating fibres, threads, yarns, fabrics, or fibrous goods made from such materials, with macromolecular compounds; Such treatment combined with mechanical treatment
- D06M15/19—Treating fibres, threads, yarns, fabrics, or fibrous goods made from such materials, with macromolecular compounds; Such treatment combined with mechanical treatment with synthetic macromolecular compounds
- D06M15/37—Macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
- D06M15/61—Polyamines polyimines
-
- D—TEXTILES; PAPER
- D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
- D01F—CHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBON FILAMENTS
- D01F11/00—Chemical after-treatment of artificial filaments or the like during manufacture
- D01F11/10—Chemical after-treatment of artificial filaments or the like during manufacture of carbon
- D01F11/14—Chemical after-treatment of artificial filaments or the like during manufacture of carbon with organic compounds, e.g. macromolecular compounds
-
- D—TEXTILES; PAPER
- D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
- D01F—CHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBON FILAMENTS
- D01F11/00—Chemical after-treatment of artificial filaments or the like during manufacture
- D01F11/10—Chemical after-treatment of artificial filaments or the like during manufacture of carbon
- D01F11/16—Chemical after-treatment of artificial filaments or the like during manufacture of carbon by physicochemical methods
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
- H01B1/00—Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors
- H01B1/06—Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors mainly consisting of other non-metallic substances
- H01B1/12—Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors mainly consisting of other non-metallic substances organic substances
- H01B1/124—Intrinsically conductive polymers
- H01B1/128—Intrinsically conductive polymers comprising six-membered aromatic rings in the main chain, e.g. polyanilines, polyphenylenes
Definitions
- the subject of the present invention is an industrial process for continuously impregnating a porous substrate with an doped electronic conductive polymer and more particularly with a polyaniline.
- This substrate is in particular a fabric.
- Fabrics with controlled electronic conductivity obtained by depositing a conductive phase on the surface of their fibrils, are materials which arouse much interest in view of the industrial applications to which they are devoted.
- These fabrics are in particular used as antistatic material, materials absorbing electromagnetic waves (shielding of electronic devices for example), or as active material in electrochemical systems, ...
- the first known technique is electrochemical synthesis in the liquid phase.
- a container filled with an electrolytic solution is used in which an anode and a cathode are immersed.
- This solution contains a polymerizable liquid monomer by oxidation in the form of the polymer and a dopant of this conductive polymer.
- the passage of a current between the anode and the cathode leads to an electrochemical oxidation of the monomer initiating its polymerization.
- a conductive polymer film is then deposited on the anode.
- the second known technique is chemical synthesis in the vapor phase. It is notably described in document US-A-4,696,835 and in document FR-A-2,666,438.
- the substrate is previously impregnated with a solution containing an oxidizing agent of the monomer to be polymerized. After drying, the substrate is exposed to vapors of the monomer which polymerizes on the surface of the substrate.
- the third known technique is chemical synthesis in the liquid phase. It is notably described in documents US-A-4 803 096, EP-A-0 352 882 and in the article by Y. F Nicolau and M. Nechtschein, Springer Séries in Solid-State Sciences, vol. 91, pp . 461-464, Electronic properties of Conjugated Polymers III.
- US-A-4 803 096 describes an impregnation technique which consists in immersing the tissue in a bath containing the monomer, the oxidant and the doping agent, at relatively dilute concentrations. The freshly formed oligomers adsorb on the substrate and then their growth by epitaxy makes it possible to cover each fibril of the tissue uniformly and individually.
- This deposition technique concerns both polyaniline and polypyrrole.
- the thickness of the film obtained is very low, of the order of 8 nm / cycle.
- the subject of the present invention is precisely a new process for impregnating a substrate continuously with an electronic conductive polymer which in particular makes it possible to remedy the above drawbacks.
- this process is an industrial process allowing the continuous treatment of long lengths of substrate at speeds higher than those of the prior techniques.
- the time for impregnating a substrate according to the invention lasts only a few minutes.
- the impregnated substrate has a high electrical conductivity which can reach or even exceed 2S / cm.
- the electrical resistivity of the impregnated substrate can be very low and less than 30 ohms / square.
- the subject of the invention is a process for continuous impregnation of a porous substrate with a doped electronic conductive polymer, consisting in subjecting the moving substrate to at least one treatment cycle comprising the following steps:
- the degree of impregnation of the substrate results from the competition between the adsorption and the redissolution of the monomer in the oxidizing solution.
- the adsorbed species therefore remain close to the surface of the substrate and the yield relative to the monomer is important.
- the intrinsic conductivity of the polymer deposit can reach 30S / cm.
- the number of impregnation cycles depends in particular on the thickness of polymers sought, on the surface of the substrate. This thickness depends on the particular application envisaged.
- the thickness of the deposit obtained for each passage varies from 30 to 150 nm depending on the rank of the passage, which is at least 10 times greater than in the Nicolau and Nechtschein process.
- the process is perfectly continuous, which makes it possible to process long lengths of substrate and in particular of fabric of various natures and in a uniform manner at a rate of the order of a meter / minute. This speed makes it possible to reconcile the different times of the process while limiting the dead length of the substrate to a length of less than 20 m throughout the installation.
- the process of the invention uses current commercial products, which are not very toxic and inexpensive in order to be compatible with the processes conventionally used in industry.
- This method also allows modulation of the electrical conductivity of the substrate: depending on the application envisaged. This conductivity can be modulated by adjusting the following parameters:
- the number of treatment cycles varies from 1 to 7 in practice.
- aniline derivatives which can be used in the invention, mention may be made of para (aminadiphenylamine) and its orthosubstituted derivatives such as orthotoluidine, orthoaminophenol and orthocarboxyaniline.
- the monomers used are soluble in the form of a salt in aqueous solution such as aniline hydrochloride, aniline sulfate or aniline paratoluene sulfonate.
- the oxidizing agents used are agents with rapid oxidation kinetics and whose REDOX potential is ⁇ 1 volt compared to the hydrogen electrode.
- the oxidants used are conventional oxidants widely available commercially and therefore inexpensive, unlike the vanadium oxides recommended in patent EP-A-0 352 882.
- these oxidants are chemically stable in an acid medium.
- oxidizing agents which can be used in the invention, mention may be made of double ammonium and cerium nitrate, peroxides such as osmium tetra-oxide, ammonium persulfate, iodate of potassium, potassium dichromate.
- the process of the invention uses aqueous solutions and is therefore free of flammable solvents which could compromise the safety of the installation, unlike the method described by Nicolau and Nechtschein.
- the use of aqueous solutions is much less expensive than the use of organic solvents.
- the oxidizing solution used is advantageously an acid solution.
- acid solution by acid solution must be understood a solution having a pH of less than 2 and typically equal to 0.
- the acid used can be sulfuric acid, perchloric acid, hydrochloric acid, tetrafluoroboric acid, paratoluene sulfonic acid.
- hydrofluoric acid is not suitable for use in an industrial environment because of its toxicity and its volatility.
- the acid used to wash the polymer deposit and that used to deposit the monomer may be the same or different from that used in the oxidizing solution.
- light acids HNO 3 , HCl
- H 2 SO 4 is particularly not recommended, as well as paratoluene sulfonic acid.
- the porous substrate may be an insulating polymeric film, for example a polyvinyl chloride, polystyrene, polyethylene film; the substrate can also be a textile in particular a glass fabric, carbon fibers, a synthetic fabric. It can also be a conductive (for example metal) or semiconductor sheet or fabric.
- an insulating polymeric film for example a polyvinyl chloride, polystyrene, polyethylene film
- the substrate can also be a textile in particular a glass fabric, carbon fibers, a synthetic fabric. It can also be a conductive (for example metal) or semiconductor sheet or fabric.
- the surface of the latter must contain defects (scratches for example) in order to ensure the adsorption of the oligomers; the deposition of polymer is essentially a physical phenomenon.
- the substrate is showered with a clean acidic washing solution containing the same acid as that of the washing solution of step e, between steps e and f.
- This shower ensures in particular an ultimate washing of the impregnated substrate.
- the substrate is advantageously showered with a clean oxidizing solution of the same composition as that of the oxidizing solution of step c, between steps c and d.
- the method of the invention comprises at least one step of draining the substrate after passage of the latter in at least one of the solutions.
- This draining step is in particular provided before step b) of drying the substrate.
- a draining step is carried out after passage of the substrate in each of the aqueous, oxidizing and washing solutions.
- Steps a) and c) of impregnating the substrate advantageously last from 5 to 60 seconds.
- Drying steps b) and f) can be set from 1 to 10 minutes.
- the washing step is adjustable between 30 and 120 seconds and the draining steps can vary from 5 to 60 seconds.
- the description below will be made for a non-conductive fabric, taking into account the particular applications of such a substrate made conductive.
- the fabric is in particular a glass fabric.
- This fabric bearing the reference 2 is continuously unwound from a support reel 4.
- the speed of movement of the fabric during a whole treatment cycle is from 1m / min to 5m / min.
- the fabric is first impregnated with a roller by a monomer impregnation bath 6 for 5 to 30 seconds, contained in an impregnation tank 1.
- This solution is an acid solution having a pH less than or equal to 2, containing a liquid monomer soluble or in a solution of the salt obtained by acid-base reaction of the monomer with the corresponding acid in water, polymerizable by oxidation at a concentration, in practice from 0.25M to 4M. (The saturation in monomer is quite possible).
- the fabric impregnated with monomer is then drained for 5 to 30 seconds. This step is symbolized in 7. It is then dried in a hot air dryer 8 at a temperature ranging from 40 ° C to 80 ° C for a period of 1 to 10 minutes depending on the nature of the monomer impregnation bath.
- the fabric 2 is then brought into an oxidizing impregnation bath 9 contained in an impregnation tank 3.
- This bath is an oxidizing solution containing a doping agent of the conductive polymer to be produced. Impregnation takes place with a roller for 5 to 60 seconds depending on the exact nature of this bath.
- This is an acid solution of pH ⁇ 2, in particular hydrochloric acid containing ammonium persulfate, potassium dichromate or potassium iodate.
- the oxidant concentration is, in practice, chosen from 0.005N to 0.03N and preferably ⁇ 0.02N to avoid over-oxidation.
- the fabric 5 is advantageously sprayed with an oxidizing impregnation bath of the same composition as that of the bath 9, just above the impregnation tank 3.
- the overflow bath 9 escaping from the top of the tank 3 ensures a continuous renewal of the latter.
- the step of impregnating the oxidant including the showering step 5 is carried out for 5 to 60 seconds.
- the fabric impregnated with oxidant is again drained for 5 to 60 seconds in air. This step is symbolized in 10.
- This step is symbolized at 11. It is carried out in the open air, the fabric moving from one roll to another.
- the fabric 2 coated with conductive polymer is then washed in an acidic washing bath 12 having a pH of less than 2, contained in a washing tank 17.
- the washing solution is in particular a hydrochloric acid solution. This washing is then optionally followed by a shower 13 with clean acid, for example with an HCl solution of 1 to 4M.
- This showering step 13 ensures ultimate washing of the substrate.
- this shower is carried out just above the washing tank 17, it ensures the continuous renewal of the washing solution 12, the overflow of the washing solution escaping from the top of the tank 17.
- this solution 12 has a stationary state over time.
- the total duration of washing (washing + showering) is adjustable from 30 to 120 seconds; the actual washing in the bath 12 lasts from 20 to 80 seconds and the showering 13 lasts from 10 to 40 seconds.
- the polymer coated fabric is drained for 10 to 100 seconds as indicated in 14 and is then passed through an oven 13 to be dried again between 40 ° C and 80 ° C for 2 to 10 minutes. Drying is carried out using a flow of hot air under the same conditions as drying 8.
- the impregnated and dry fabric is then received by a spool 16. It is ready for use.
- the fabric used in these examples consists of 17.5 threads per cm of warp and 8 threads per cm of weft.
- the diameter of the unitary filament is 9 ⁇ m.
- the fabric has a surface mass of 240g / m 2 and a thickness of 230um.
- the glass cloth After draining for 15 s and drying at 60 ° C. for 6 min, the glass cloth is impregnated with the oxidizing solution for 15 s (see table), first in the form of a shower and then by passage through the bath 9.
- the fabric is drained for 10 s and dried at 60 ° C for 6 min.
- the duration of a treatment cycle is 18 min and 25 s.
- the same glass fabric as that used in the above examples was treated by scrupulously following the method described by Nicolau and Nechtschein where the aniline is oxidized by a solution of 3M FeCl3 of pH equal to 0.
- the conductivity of the fabric thus impregnated was only 10 -6 S / cm for a treatment cycle.
- the oxidant used must be stable in an acid medium, in particular in an HCl medium, which is not the case for KMnO 4 which leads to the release of chlorine and therefore to a toxic reaction and for H 2 O 2 which decomposes.
- the aniline hydrochloride monomer is in a concentration of 2M (instead of 1M),
- reaction time after the 15s following the impregnation in oxidizing solution is 1 min and 30s (instead of 4 min and 30s),
- the duration of a treatment cycle is only 8 min and 25 s, which is extremely short.
- the thickness deposited is considerably smaller because the monomer, in the form of aniline hydrochloride, is very quickly dispersed in the oxidizing solution since it is remained in the liquid state.
- the intrinsic conductivity corresponding to this example is also weakened compared to the samples which have been dried.
- the monomer used was aniline.
- Very comparable results are obtained by replacing in each example the aniline with one of the following compounds: para (aminodiphenylamine) or one of its orthosubstituted derivatives such as orthotoluidine, orthoaminophenol and orthocarboxyaniline .
- para aminodiphenylamine
- orthosubstituted derivatives such as orthotoluidine, orthoaminophenol and orthocarboxyaniline .
- the process of the invention has been optimized to be perfectly suited to the industrial environment, unlike the known processes.
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- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Engineering & Computer Science (AREA)
- Textile Engineering (AREA)
- General Chemical & Material Sciences (AREA)
- Physics & Mathematics (AREA)
- Spectroscopy & Molecular Physics (AREA)
- Macromolecular Compounds Obtained By Forming Nitrogen-Containing Linkages In General (AREA)
Abstract
Description
Claims
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE69321721T DE69321721T2 (de) | 1992-06-05 | 1993-06-03 | Verfahren zur kontinuierlichen imprägnierung mit einem elektronischen leitfähigem polymer |
EP93913084A EP0643868B1 (fr) | 1992-06-05 | 1993-06-03 | Procede d'impregnation d'un substrat en continu par un polymere conducteur electronique |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FR92/06846 | 1992-06-05 | ||
FR9206846A FR2691988B1 (fr) | 1992-06-05 | 1992-06-05 | Procede d'impregnation d'un substrat en continu par un polymere conducteur electronique. |
Publications (1)
Publication Number | Publication Date |
---|---|
WO1993026012A1 true WO1993026012A1 (fr) | 1993-12-23 |
Family
ID=9430484
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/FR1993/000528 WO1993026012A1 (fr) | 1992-06-05 | 1993-06-03 | Procede d'impregnation d'un substrat en continu par un polymere conducteur electronique |
Country Status (4)
Country | Link |
---|---|
EP (1) | EP0643868B1 (fr) |
DE (1) | DE69321721T2 (fr) |
FR (1) | FR2691988B1 (fr) |
WO (1) | WO1993026012A1 (fr) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO1999015725A1 (fr) * | 1997-09-23 | 1999-04-01 | Zipperling Kessler & Co. (Gmbh & Co.) | Preparation de fibres contenant des polymeres intrinsequement conducteurs |
CN112813535A (zh) * | 2021-02-09 | 2021-05-18 | 青岛大学 | 一种导电复合海藻纤维及其制备方法 |
US11655379B2 (en) | 2018-10-24 | 2023-05-23 | University Of Electronic Science And Technology Of China | Composite conductive polymers, preparation method and application thereof |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE3321281A1 (de) * | 1982-06-22 | 1983-12-22 | ASEA AB, 72183 Västerås | Verfahren zur erhoehung der elektrischen leitfaehigkeit impraegnierbarer materialien |
US4617228A (en) * | 1984-09-04 | 1986-10-14 | Rockwell International Corporation | Process for producing electrically conductive composites and composites produced therein |
Family Cites Families (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS6476613A (en) * | 1987-09-18 | 1989-03-22 | Japan Carlit Co Ltd | Making base material with electric insulation conductive continuously |
JPH02281509A (ja) * | 1989-04-24 | 1990-11-19 | Hokushin Ind Inc | 導電性複合材の製造方法 |
-
1992
- 1992-06-05 FR FR9206846A patent/FR2691988B1/fr not_active Expired - Fee Related
-
1993
- 1993-06-03 DE DE69321721T patent/DE69321721T2/de not_active Expired - Fee Related
- 1993-06-03 EP EP93913084A patent/EP0643868B1/fr not_active Expired - Lifetime
- 1993-06-03 WO PCT/FR1993/000528 patent/WO1993026012A1/fr active IP Right Grant
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE3321281A1 (de) * | 1982-06-22 | 1983-12-22 | ASEA AB, 72183 Västerås | Verfahren zur erhoehung der elektrischen leitfaehigkeit impraegnierbarer materialien |
US4617228A (en) * | 1984-09-04 | 1986-10-14 | Rockwell International Corporation | Process for producing electrically conductive composites and composites produced therein |
Non-Patent Citations (2)
Title |
---|
DATABASE WPIL Section Ch, Week 01, Derwent Publications Ltd., London, GB; Class A85, AN 91-003971 * |
DATABASE WPIL Section Ch, Week 18, Derwent Publications Ltd., London, GB; Class A85, AN 89-132911 * |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO1999015725A1 (fr) * | 1997-09-23 | 1999-04-01 | Zipperling Kessler & Co. (Gmbh & Co.) | Preparation de fibres contenant des polymeres intrinsequement conducteurs |
US11655379B2 (en) | 2018-10-24 | 2023-05-23 | University Of Electronic Science And Technology Of China | Composite conductive polymers, preparation method and application thereof |
CN112813535A (zh) * | 2021-02-09 | 2021-05-18 | 青岛大学 | 一种导电复合海藻纤维及其制备方法 |
Also Published As
Publication number | Publication date |
---|---|
FR2691988B1 (fr) | 1995-07-13 |
DE69321721D1 (de) | 1998-11-26 |
EP0643868A1 (fr) | 1995-03-22 |
FR2691988A1 (fr) | 1993-12-10 |
DE69321721T2 (de) | 1999-05-20 |
EP0643868B1 (fr) | 1998-10-21 |
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