FI94056C - Non-conductive plastics material and process for making the same - Google Patents

Description

94056 5 Electrically conductive plastic material and method of making the same

The invention relates to a process for producing a solid electrically conductive plastic material, in which polyaniline or a derivative thereof is brought into contact with an organic sulfonic acid or a derivative thereof. The invention also relates to a solid, electrically conductive plastic material produced by this method 10.

Electrically conductive polymers are currently being studied extensively in the world. These polymers offer the potential to replace metal conductors and semiconductors in many applications such as batteries, sensors, switches, photocells, circuit boards, thermocouples, antistatic protection (ESD), and electromagnetic interference suppression (EMI). The advantages of electrically conductive polymers over metals are e.g. their lightness, mechanical properties, corrosion-20 resistance, and cheaper synthesis and machining methods.

Electrically conductive plastics can be roughly divided into two different groups: filled electrically conductive plastics in which an electrically conductive filler, e.g. carbon black or soot, carbon fiber, metal powder, etc., is added to a disposable or thermoplastic resin, and internally electrically conductive plastics based on oxidation or to polymers made electrically conductive by reduction (doping).

The electrical conductivity of filled electrically conductive polymers depends on the mutual contact of electrically conductive filler particles. Generally, about 10-50% by weight of a well-dispersed filler is required to provide highly conductive composites. However, such conductive composites have problems: their mechanical and some chemical properties deteriorate decisively as the filler content increases and the polymer content decreases, their electrical conductivity is difficult to control, especially in the semiconductor region, and their filler is permanently and homogeneously dispersed in the matrix.

Internally conductive plastics can be made from organic polymers with long conjugated chains of double bonds or double bonds and heteroatoms. Stable π-electron systems in double bonds and heteroaters can be disrupted by the addition of certain dopants to the polymer, which are either electron acceptors or donors. Thus, gaps and / or extra electrons are created in the polymer chain, which allow an electric current to flow along the conjugated chain.

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The advantage of internally electrically conductive plastics is that their electrical conductivity can be easily modified as a function of doping time, which is especially evident in the case of low conductivities. With filled electrically conductive plastics, achieving low conductivities is difficult. Examples of electrically conductive polymers are polyacetylene, poly-p-phenylene, polypyrrole, polythiophene and polyaniline.

However, the workability and stability properties of most internally electrically conductive polymers do not yet allow their use in said applications.

It is expected that if a composite material consisting internally of an electrically conductive polymer (acting as an electrical conductor) and a thermoplastic polymer (which would primarily impart the necessary mechanical and similar properties to the composite) could be melt processed, it would be possible to produce an electrically conductive plastic material excellent properties compared to the above-mentioned filled electrically conductive plastic composites.

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One technically and commercially promising internally electrically conductive polymer is polyaniline with its derivatives. The aniline nipolymer is based on an aniline unit whose nitrogen atom is attached to the para-carbon of the benzene ring of the next unit.

Unsubstituted polyaniline can exist in several forms, including leukoemeraldine, protoemeridine, emeraldine, nigraniline, and tolu-protoemeraldine forms.

The so-called polyaniline the emeraldine base form is generally described by the molecular formula (-O 2 - (-OO-) 15 where x is about 0.5

However, polyaniline, like almost all other internally electrically conductive polymers, has a problem of poor processability, i.e. it is difficult to form the desired objects, film, fiber, etc. from the polymer.

There are two main machining methods for machining conductive polymers: melt machining and solution machining. The problems of melt processing of electrically conductive polymers are due to the fact that. In the case of a polymer, thermal decomposition begins before the polymer melts or plasticizes. The problem with solution processing of conductive polymers is the poor solubility of internally conductive polymers in conventional industrial solvents. Another problem is that solution processing can be used to form films and fibers from which the solution can be • evaporated, but solution processing is not suitable for the production of commonly used moldings.

EP-432 929 discloses some alternatives which have attempted to solve machinability. U.S. Pat. Nos. 3,963,498 and 4,025,463 describe oligomers of polyaniline having less than 8 aniline units and soluble in certain organic solvents. However, oligomers lack the good mechanical and chemical properties of polymers.

The closest practical solutions useful in industrial operations are found in U.S. Pat. No. 5,006,278, WO8901694, WO9013601, WO9010297, WO9001775 and U.S. Pat. No. 5,002,700. Of these, U.S. Pat. No. 5,006,278 discloses an electrically conductive product obtained by mixing 10 dopant and polyaniline, after which the solvent has been removed from the mixture. WO8901694 discloses a solution-processable polyaniline doped with a sulfone sleeve. The polyaniline of this patent is useful in the processing of conductive polymers e.g. with the following matrix-15 plastics: PE, PP, PA. WO9013601 discloses the preparation of a conductive polymer blend by first forming a mixture of polyaniline and a dopant in a suitable solvent and then mixing this with the polyamide, after which the solvent is evaporated. The dopant is an aromatic multisul-20 phonic acid. According to this publication, doping is generally carried out at a temperature of 20-25 ° C. The doping can be performed as a heterogeneous reaction, after which the mixture is dissolved in a suitable solvent. Work while the solvent is still present (p. 15, p. 23).

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WO9010297 and US-5,002,700 further disclose the use of dodecylbenzenesulfonic acid as a polyaniline dopant. WO9001775, on the other hand, discloses multisulfonic acid-30a as a dopant for polyaniline, which has the advantage of better thermal stability compared to other sulfonic acids. In the examples of this WO patent, a doping temperature of 20-25 ° C and atmospheric pressure have been used and the doping has been performed as a dispersion of polyaniline and sulfonic acid in an aqueous formic acid solution.

35

Prior art publications speak very widely that the procedures are suitable for the widest possible range of polyaniline derivatives and also for both solution and melt processing. However, application examples of the publications show that only some solution processing conditions have been found for polyaniline preprotonized with a suitable dopant. In all examples of these publications, in order to homogenize the mixture of polyaniline and doop-5 disintegrant, it must have been dissolved in a suitable solvent. This has apparently been necessary in order to make the polymer product sufficiently homogeneous and electrically conductive. In any case, it is clear that the ratios specific to smelting, verified by examples, have not been presented in the prior art.

There is also the problem of melt processing that the doped dust line or the mixture of polyaniline and dopant can be melt processed at most once. This makes it impossible to produce a homogeneous material to be melt processed, e.g. in the form of granules. Thus, in previous melt processing experiments, the components have been mechanically mixed together before melt processing into the final shape. The samples obtained in the experiments have been of varying electrical conductivity and inhomogeneous in quality.

As can be seen from the prior art, the mere mixing of an emeraldine-based polyaniline and a dopant (e.g., dodecylbenzenesulfonic acid, DBSA) is not sufficient to provide a homogeneous doped polyaniline. The mixture forms the so-called pre-protonated polyaniline / dopant mixture. This liquid mixture or dispersion is vague, staining, highly corrosive and difficult to handle. In the prior art publications, sufficient mixing to cause doping of the polyaniline has been accomplished by dissolving portions of the mixture in the same solvent.

Em. the problem of doping is also reflected in the production of a composite material from doped polyaniline and a ter-35 moplastic polymer. Thus, in preliminary experiments of the present invention, it has been found that mixing polyaniline and dopant DBSA with a thermoplastic polymer does not produce a homogeneous, melt-fit body. The specimens made in this way had various flow marks, bubbles and cracks as visible defects. The problem is related to the poor compatibility of the polyaniline and / or dopant or doped polyaniline with the thermoplastic polymer under melt processing conditions.

It is an object of the present invention to provide a highly electrically conductive polyaniline. The invention also relates to an easy-to-process conductive polyaniline which is homogeneous, non-sticky, non-corrosive and suitable for melt processing. At the same time, the polyaniline must be compatible with other thermoplastic polymers in order to be melt processed into a composite material without additional steps, such as solution treatment. Good melt processability should also include the ability of the conductive polyaniline to withstand multiple melt processing, e.g., granulation, without compromising its essential conductive et al. properties deteriorate. In addition, inert and chemically stable conductive polyaniline and the plastic materials containing it are sought.

The above objects have now been achieved by a new method and product, which is mainly characterized by what is stated in the characterizing parts of the respective claims 1 and 14. Thus, it has been found that a solid, electrically conductive plastic material having said good properties can be obtained by heat treating a reaction product or mixture of polyaniline or a derivative thereof with an organic sulfonic acid or a derivative thereof by stirring in a su-blender at a temperature of about +100 to + 250 ° C.

·. Namely, it was surprisingly found that a preprotonated mixture of polyaniline or a derivative thereof and a sulfonic acid or a derivative thereof, which is an indeterminate, sticky, highly corrosive and difficult-to-handle liquid mixture or dispersion, easily becomes homogeneous, solid, relatively powder or meal to be treated.

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In the process of the invention, it was necessary to first form a mixture or reaction product of polyaniline or a derivative thereof and an organic sulfonic acid or a derivative thereof, which was heat-treated in a stirrer. Only from the mixture or reaction product treated in this way was a dry solid obtained, which together with the thermoplastic polymer was able to form homogeneous bodies without visible flow marks or other surface defects and at the same time were sufficiently electrically conductive.

10

According to a preferred embodiment of the invention, the reaction product or mixture of polyaniline or a derivative thereof and an organic sulfonic acid or a derivative thereof is heat-treated while stirring, e.g. with a screw mixer or compounder. It has also been found that it is advantageous to use a screw mixer with an open structure, and in particular one with an open cylinder outlet end.

As mentioned above, the invention relates in its broadest form to the heat treatment of a reaction product or mixture of polyaniline or a derivative thereof and an organic sulfonic acid or a derivative thereof to solidify the product and improve its properties. This is based on the finding that the heat treatment solidifies the reaction product and improves its handling and machining properties. Perhaps the most important embodiment of the invention relates to the machining properties of the reaction product, according to which the above-mentioned heat-treated reaction product or mixture is further mixed with a thermoplastic polymer and melt-processed with it into a composite material.

: Melt processing can take place at any temperature at which the thermoplastic polymer in question is found to melt processing. The melt processing method and the device used in the method with its parameters can also be chosen starting from the rheology of the melt formed by the thermoplastic polymer in question and the heat-treated conductive polyaniline. Typical melt processing equipment includes, for example, kneaders and screw mixers, extruder crosses, charge and transfer presses, and injection molding presses. The method and product according to the invention are particularly well suited for injection molding, with the best injection molding polymers being the preferred thermoplastic polymer components.

5

In selecting the material components and reaction parameters of the process of the present invention, the following result was obtained. The reaction product of polyaniline or a derivative thereof and an organic sulfonic acid or a derivative thereof is preferably treated at a temperature of about +150 to + 210 ° C. It is also preferred to heat treat said reaction product at a pressure of 0.1 to 1000 bar, especially at a pressure of 0.1 to 100 bar.

Prior art publications, e.g. WO90 / 10297, 15, which is hereby incorporated by reference into the application, list those polyaniline derivatives which can also be used as the lead polymers of this invention.

As the polyaniline or derivative thereof, unsubstituted polyaniline is preferably used, for example in the form of leukoemeraldine, protoemeraldine, emeraldine, nigraniline or tolu-protoemeraldine. The most preferred form of unsubstituted polyaniline is the emeraldine base form.

The polyaniline used as the conducting polymer may be prepared in any manner, for example electrochemically or chemically. For example, the aniline can be prepared by treating the aniline in solution with ammonium persulfate-30 in excess 1 M hydrochloric acid. A blue-green electrically conductive form of polyaniline precipitates from solution. When treated with ammonium hydroxide in ethanol, the emeraldine base form of polyaniline is obtained, which is black and almost electrically non-conductive.

35

Polyaniline having a molecular weight of at least about 5,000 g / mol, and preferably about 9,940,500 to 15,000 g / mol, is best suited for conventional use. Since polyaniline repeat units are defined as one monomer unit consisting of two aniline units, it follows that polyaniline macro-5 molecules should contain, on average, at least about 150 monomer units. However, in some special cases, the molecular weight or degree of polymerization may be lower.

As the sulfonic acid or its derivative, a sulfonic acid is preferably used, more preferably an aromatic sulfonic acid and most preferably dodecylbenzenesulfonic acid.

In the process according to the invention, the weight ratio: (polyaniline 15 or a derivative thereof) / (sulfonic acid or a derivative thereof) is preferably between about 0.05-2, in particular between about 0.1-1, based on unsubstituted polyaniline.

The experiments showed that the heat-treated reaction product or mixture prepared by the process of the invention can be melt-processed with all major thermoplastic polymers. In one embodiment, the thermoplastic polymer is a homo- or copolymer based on styrene or a derivative thereof, or a mixture thereof. These include polystyrene, styrene-acrylonitrile copolymer, acrylonitrile-butadiene-styrene copolymer, methyl methacrylate-butadiene-styrene copolymer, poly- (p-, m- and o-alkylstyrenes), poly-alpha-styrene).

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The thermoplastic polymer may also be a vinyl homopolymer or copolymer or a mixture thereof such as polyvinyl chloride, polyvinyl acetate, polyvinyl alcohol and polyvinyl acetals. Vinyl polymers also include acrylic polymers such as polymethyl methacrylate.

The thermoplastic polymer may also be an olefin polymer or copolymer or a mixture thereof, such as polyethylene, polypropylene, polycutylene, polybutylene or polymethylpentene. It may also be a thermoplastic condensation polymer such as polyamide, linear polyester, polyacetal or polycarbonate.

In the melt processing of a heat-treated reaction product or mixture of polyaniline or a derivative thereof with an organic sulfonic acid or a derivative thereof and a thermoplastic polymer, their weight ratio can be any Theologically usable product, with a preferred ratio of about 0.05 PANI + DBSA / (thermoplastic polymer). 10.

However, the proportion of polyaniline and organic sulfonic acid in the total mixture may also be below this limit, for example when only a slight antistatic effect is desired for the product.

When heat treating the reaction product or mixture of polyaniline or a derivative thereof and an organic sulfonic acid or a derivative thereof, a little thermoplastic polymer may also be added to the heat treatment itself. The reaction product should then contain at most 50% and preferably at most 25% by weight of a thermoplastic polymer, which is preferably the same polymer used in the subsequent heat-treated reaction. in the melt processing of a thio product and a thermoplastic polymer as a composite material. It is thus a kind of pretreatment with the thermoplastic polymer in question in order to improve compatibility.

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The invention also relates to a solid electrically conductive plastic material prepared by contacting a polyaniline or a derivative thereof with an organic sulfonic acid or a derivative thereof. According to the invention, the plastic material is solidified and brought into a useful form by reacting polyaniline or a derivative thereof with an organic sulfonic acid or a derivative thereof, preferably by heat treatment at a temperature of about +100 to + 250 ° C. It is possible that complex formation also occurs at room temperature when the treatment time is long enough.

The electrically conductive plastic material according to the invention is surprising and new in structure, as it differs in nature from a completely unheated reaction product or mixture of polyaniline or a derivative thereof and an organic sulfonic acid or a derivative thereof. Namely, it is in the form of a dry powder 10 or granulate which, unlike an undeveloped reaction product or mixture, is not stained, highly corrosive or difficult to handle.

As already mentioned, the conductive plastic material 15 according to the invention is a reaction product of polyaniline or a derivative thereof and an organic sulfonic acid or a derivative thereof, which is preferably obtained by heating the above reagents together.

The reaction product is characterized by an exothermic peak different from polyaniline as measured by differential scanning calorimetry (DSC), which indicates a uniform phase change (e.g. melting point) upon heating.

When the polyaniline has an endothermic range at 171 ° C and after heat treatment at 180 ° C, the conductive plastic material of the invention has an exothermic range at 110-170 ° C. Thus, the polyaniline consumes heat and the reaction product of the invention releases heat.

The reaction product is also characterized in that it has a comb-like ker-> ♦ 12 94056 debris structure detectable by X-ray diffraction geometry as opposed to a polyaniline having a conventional crystal structure.

The heat-treated reaction product or mixture according to the invention is preferably processed by mixing it with a thermoplastic polymer and melt-processing them together into a composite material.

According to one embodiment, the composite material contains 10 oriented phases which, based on microscopic images, disappear at about 10-20 ° C below the melting point of the thermoplastic polymer component. Since the melting point of the thermoplastic polymer component of the composite material is lower than the melting point of the corresponding pure thermoplastic polymer, it is assumed that the conductive plastic material is at least partially dissolved in the thermoplastic polymer.

Embodiments 20 In the following, the invention will be described in more detail on the basis of exemplary embodiments. Three sets of experiments were performed in the experiments, the first of which did not represent the method according to the invention.

In all experiments, a protonated dispersion of polyaniline and dodecylbenzenesulfonic acid was first made. This pre-protonated dispersion was mixed with a matrix plastic to form a solid electrically conductive polymer-containing specimen. Appearance of the test piece, e.g. homogeneity, was assessed visually and the test piece was determined for electrical conductivity.

The conducting polymer used in the experiments was the emeraldine base form of polyaniline.

35

Two different forms of dodecylbenzenesulfonic acid were used as the dopant (i.e., counterion). One was refined Tokyo Kasei grade and the other was commercial grade Sulfosoft.

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As the thermoplastic polymer component of the melt-processed composite material, i.e. the matrix plastic, in which the doped polyaniline was mixed, e.g. polystyrene, soft PVC and polyethylene (HDPE).

5

Test equipment

In the machining experiments, a device modified for the injection molding machine Ferromatik FR-40 was used, which is particularly suitable for mixing and melt processing of small to about 10 g of polymer batches and consists of a mixing screw and a feed piston connected to it.

The resistance of the test pieces was measured with a multimeter by attaching measuring pliers to the ends of the piece. The measurement results obtained with this method are of the order of magnitude correct, but not quite accurate, because the contact between the measuring pliers and the plastic piece varies during the measurement and is different with each attachment. However, the general principle in the 20 measurements was considered to be the way in which the measuring pliers were placed in place by hand pressing and at the same time rotating. The piece with its sensors was then left free on the table and the meter was read once the display had stabilized. Only samples 53 and 54 have been measured by the two-point method.

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Comparative Experiments 1-17 (Method A)

Method A is a previously used method in which preprotonated polyaniline, dodecylbenzenesulfonic acid and a granule or powder of a thermoplastic plastic, i.e. a matrix plastic, are mixed directly and thoroughly together to obtain

• I

da time the final product piece.

The mixing ratios used in the experiments are shown in Table 1.

35 In these experiments, the ingredients were weighed individually in a vessel in which premixing was performed before feeding to the mixing device. It is not known exactly what happens in this premixing or preprotonation step. Apparently, a weak chemical bond is formed between the polyaniline and the dopant because the components of the mixture can no longer be completely separated. On the other hand, the bond between the polyaniline and the dopant is not strong enough to still form a true electrically conductive polymer.

For this reason, the premixing step is also called pre-protonation.

The premixed mixture of polyaniline and dodecylbenzene sulfonic acid was combined with any matrix plastic and transferred to a blender. In the mixer, the polyaniline pre-protonated with dodecylbenzenesulfonic acid was mixed with several flask feeds of the mixer.

15 Table 1. Processing conditions in the mixer by method A

Experiment PANI + matrix ratio T mixing resistance- Weight ratio no. DBSA plastic PANI / cycles measurement (PANI + DBSA) 20 g g DBSA ° C / polym.

1 9 4 PS 1: 4 180 20 0.2 kΩ 2.25 2 4.5 8 PS 1: 7 200 20 0.4 kÖ 0.56 3 1.2 10.8 PS 1: 4 180 20 235 ΜΩ 0 , 11 25 4 4 8 PS 1: 4 180 10 8 kfl 0.50. 54 8 PS 1: 6 180 10 70 kD 0.30 6 4 8 PS 1: 3 180 10 3 kΩ 0.50 7 4 8 PS 1: 2 180 10 70 k «0.50 8 4 8 PS 1: 4 180 10 1.5 kΩ 0.50 30 9 4 8 PS 1: 4 200 10 12 kQ 0.50 10 4 8 PS 1: 4 200 10 15 ΜΩ 0.50 11 4 8 PS 1: 4 170 5 1 kÖ 0, 50 12 4 8 LDPE 1: 4 170 10 40 ΜΩ 0.50 13 4 1 8 PS 1: 4 170 5 6 kS 0.50 35 14 4 1 8 PS 1: 3 170 5 10 kΩ 0.50 15 4 1 8 PS 1: 4 170 5 4 kti 0.50 16 4 1 8 PS 1: 3 170 5 7 kΩ 0.50 17 4 1 8 PS 1: 1 170 5 140 kΩ 0.50 15 94056

Abbreviations used in the table: PANI = polyaniline, DBSA = dodecylbenzenesulfonic acid dopant, PS = polystyrene, T * temperature, LDPE = polyethylene, 1 polyaniline was dried at 3 h / 90 ° C.

5

The best of the resistance measurement results are the mixtures no. 1 and 2, in which the resistance is of the order of 0.2 to 0.4 kS. The surface and appearance of the two samples are almost the same. Well. 2, however, feels a little greasy on the surface than no. 1. Molem-10 where pieces show strong flow marks. In Experiment 3, a mixture of 1 part by weight of PANI and 4 parts by weight of DBSA was first made. The best of the samples was no. 5.70 kQ, where (1: 4 PANI / DBSA) the mixture was 30% of the total mixture. When PANI / DBSA mixtures were prepared for the next day's experiments 15, the conductivity of the obtained pieces was significantly lower than that of the pieces made the previous day. The mixtures were stored in an open container at about 20 ° C. The songs show strong traces of flow.

20 According to the resistance measurements, the mixture ratios (1: 4) and (1: 3), when the proportion of PA-NI / DBSA in the whole body is about 30%, give the best results (molar ratio 1: 1 corresponds to weight ratio 1: 3.57). Experiments no. 8-11 show resistance increases with increasing mixing time. Similarly, raising the temperature from 170 ° C to 200 ° C 25 increases the resistance. All pieces made according to Method A had strong flow marks and bubbles.

The disadvantages of the mixing method A according to the prior art, in which the premixed PANI / DBSA mixture or reaction product was not heat-treated, are e.g. fluctuations in conductivity values, unevenness of surface quality and pasteiness, and machining difficulties caused by the "liquid" complex on commercial machine tools. The effect of further drying was elucidated by later sampling by Method A. The result improved 35 slightly, but there are still strong traces of flow in the pieces.

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Performance Tests 1-45 (Method B)

Method B is initially started with a protonated polyaniline, i.e. a reaction product or mixture of polyaniline and dodecylbenzenesulfonic acid. This is then made by vigorous mechanical mixing and possibly injection molding of the matrix with the matrix granule or powder. This piece is ground into granules or powder with a separate device for the actual melt processing. The method requires 10 very dry PANIs, DBSAs, and an accurate premix ratio.

The mixing ratios used in the experiments, the temperature used in the mixing and the mixing times are shown in Tables 2 and 3. In the experiments, the ingredients were each weighed separately in a vessel in which premixing was performed before feeding to the mixing device.

Table 2. Processing conditions in the mixer by method B

20 Experiment PANI + matrix ratio T mixing- R Weight ratio no. DBSA plastic PANI / DBSA sections (PANI + DBSA) g g ° C / polym.

I 14 - 1: 4 170 5 200 Ω 25 2 3 9 PS 1: 4 180 5 300 kQ 0.33 3 3 9 PS 1: 4 180 5 100 kö 0.33 4 3.5 10 PA 1: 4 180 10 OL 0.38 5 3.5 10 PA 1: 4 240 10 NOT KPL 0.38 6 4 8 PS 1: 4 180 10 100 ΜΩ 0.50 30 7 4 8 PS 1: 4 170 5 20 ΚΩ 0.50 8 4 1 8 PS 1: 4 170 5 3 kQ 0.50 9 2.6 1 9.4 PS 1: 4 170 5 OL 0.27

10 ... - 1: 4 170 EI KPL

II ... - 1: 4 170 5 30 kΩ - 35 12 4 2 8 PS 1: 4 170 5 4 ΜΩ 0.50 13 14 - 1: 4 170 10 30 Ω 14 14 - 1: 3 170 5 30 Ω - 15 10 3 2 HDPE 1: 4 170 5 70 Ω 5.0 16 4 4 8 PS 1: 4 170 5 0.50 17 94056 17 14 - 1: 3 185 5 30 kÖ

18 14 - 1: 3 200 5 30 kQ

19 4 5 8 PS 1: 3 200 5 40 k «0.50 20 2 5 10 PS 1: 3 200 5 OL 0.20 5 21 4 6 8 PS 1: 3 170 5 5 kQ 0.50

Abbreviations used in the table: PANI = polyaniline, DBSA = dodecylbenzenesulphonic acid (purified grade), PS = polystyrene, T = temperature, R = resistance, LDPE = polyethylene, 10 HDPE = polyethylene, PA = polyamide, OL = out of scale, 1 = test 1 mixture, 2 = mixture of experiments 11, 3 = mixtures of experiments 11 and 13, 4 = mixture of experiments 15, 5 = mixture of experiments 18 and 6 = mixture of experiments 17 dried for 1 h at 60 ° C.

15 Tissue press no. 1 was made from PANI / DBSA 1: 4 alone. As a surprising finding, it was found that the syrupy starting mixture was converted by heat and pressure to a hard wax-like solid. Since the resistance of the sample was only about 200 Ω and it turned out to be melt-20 again in the heat, experiment no. 8, in which crushed PANI / DBSA compact was mixed with 30% polystyrene. This extrudate was almost flawless in appearance, thus differing from previous results, all of which had strong flow marks and bubbles.

25: The resistance measurement showed that the pre-compression had not increased the resistance compared to the corresponding compression made directly from the starting materials by method A. The solid shape of the preform gave reason to assume that, when ground, it could be fed to 30 injection molding cylinders among the matrix plastic. This method would thus allow the conducting polymer to be injection molded by a normal injection molding machine. Based on the above, this method was included in the following experiments for further investigation.

35

Koe no. 21 was made so that the complex extruder no. 17 was maintained at 60-80 ° C for about an hour. The 18 94056 blended injection molding blended into the PS matrix was the best in the series, but had some surface defects.

5 Table 3. Processing conditions in the mixer with method B, continued

Experiment PANI + matrix ratio T mixing- R Weight ratio no. DBSA plastic PANI / DBSA sections (PANI + DBSA) 10 g g ° C / polym.

22 4 1: 4 170 5 50 Ω - 23 14 - 1: 2,5 170 5 100 Ω 24 13 - 1: 2,5 185 10 400 Ω 15 25 13 - 1: 2,5 185 5 700 Ω 26 13 - 1: 3 170 5 200 Ω 27 13 - 1: 3 160 5 55 Ω - 28 13 - 1: 4 160 5 100 Ω 29 13 - 1: 4 170 5 50 β 20 30 4 1 8 PS 1: 2,5 170 5 15 kΩ 0.50 31 4 2 8 PS 1: 2.5 170 5 0.3 ΜΩ 0.50 32 4 3 8 PS 1: 3 170 5 5 kΩ 0.50 33 4 * 8 PS 1: 3 170 5 4 kΩ 0.50 34 14 - 1: 3 170 10 100 Ω 25 35 14 - 1: 3 170 10 100 Ω: 36 14 1: 3 175 10 400 Ω 37 14 - 1: 3 160 10 200 Ω 38 14 - 1 : 3 150 10 100 Ω 39 14 - 1: 3 160 10 100 Ω 30 40 45 8 PS 1: 4 180 10 2 kΩ 0.50 41 3.55 8.5 PS 1: 4 180 10 8 kΩ 0.29 42 2.55 9.5 PS 1: 4 180 10 40 kQ 0.26 43 35 9 PS 1: 4 180 10 80 kΩ 0.33 44 36 9 PS 1: 3 180 10 100 ΜΩ 0.33 35 45 3.77 8.3 LDPE 1: 3 180 10 200 kΩ 0.44 19 94056

Abbreviations used in the table: PANI = polyaniline, OBSA = dodecylbenzenesulfonic acid (Sulfosoft grade), PS = polystyrene, T = temperature, R = resistance, LDPE = low density polyethylene, 1 = mixture of test 23, 2 = mixture of test 24, 5 3 = mixture of Experiment 27, A = mixture of Experiment 26, 5 = mixture of Experiments 41-43, 6 = mixture of Experiment 44.

For the first time, the commercial grade dodecylbenzenesulfonic acid Sulfosoft was used in these experiments. For the experiments, 10 protonated PAN1 / DBSA mixtures were made in weight ratios of 1: 2.5, 1: 3, 1: 4, 1: 5 and 1: 6. The mixtures were stored at about 30 ° C for 3.5 days.

Experimental series 22-29 was performed on different PANI / DBSA mixtures by compression.

15 The end result was to obtain a solid product that was not sticky or moist and could be ground into small granules or powder. Comparing the resistance and tack of the extrudates, it can be seen that as the DBSA content increases, the tack increases and the resistance decreases. PS injection molds no. 30-33 showed that the so-called. with sticky extrudates the resistance was also slightly lower in the final product than with the corresponding hard extrudate e.g. 24 (1: 2.5). However, the surface of the pieces was not perfect. Experiments no. 34-45 confirm the previous-25 its result.

m. · Λ

Performance Tests 46-68 (Method C)

The best result was obtained by method C. In the method, the mold and the mixing section 30 are separated from each other, whereby the other end of the mixing cylinder and the end of the screw are visible. The temperature is adjusted as desired before the test. The solidifiable pre-protonated PANI-DBSA mixture (weight ratios of 1: 2, 1: 2, 1: 3, 1: 4 and 1: 5 were used in the experiments, all solidified) is placed in 35 feed cylinders with a piston speed adjusted to "granulate" . The screw speed in the mixing cylinder is set as desired (in experiments <300 rpm).

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The solid complex is prepared by pressing the pre-protonated PANI-DBSA from the feed cylinder through the mixing cylinder. The powdered or larger particulate dry complex or strip-like complex formed comes from the 5 open ends of the cylinder directly into the container. The solid PANI-DBSA product or masterbatch thus prepared can be mechanically mixed with matrix plastic granulate for melt processing.

10 Observing the shrinking grain from the nozzle of the mixing cylinder, it was found that only occasional gray steam rose from the open nozzle head.

A solid PANI / 15 DBSA product was prepared for injection molding experiments. The product was pre-protonated as follows: PANI / DBSA mixtures had weight ratios of 1: 3 = III, 1: 4 = IV, 1: 5 = V. The other running parameters of the device were: * The temperature in the mixing cylinder was 180 ° C.

* Screw rotation speed 180 rpm.

20

The measured throughput times and granule shape were: * Run III 3.3 g / min, dry powdery, a few larger granules, * Run IV 5.5 g / min, long non-stick granular granules.

* Run V 4.5 g / min, long stringy granules that «stick together.

The granules were stored in a sealed plastic jar.

The mixture ratios used in the experiments of method C according to the invention, the temperature used in the mixing and the mixing times / are shown in Tables 4 and 5. Table 4 shows the mixture and treatment conditions for the treatment of the pre-protonated PANI / DBSA mixture and Table 5 for the product and mat. rice plastic mixing conditions.

94056 21

Table 4. Processing conditions of preprotonated PANI / DBSA mixture in a mixer by method C of the invention

Driving Heat- Screw Drain- PANI / DBSA- 5 no. mode rotation speed ratio ° C rpm. g / min I 180 350 ... 1: 3

II

10 III 180 180 3.3 1: 3 IV 180 180 5.5 1: 4 V 180 180 4.5 1: 5 VI 170 180 4 1: 4 VII 170 180 ... 1: 4 15 VIII 170 180 .. 1: 4 IX 170 180 7 1: 3 X 180 180 ... 1: 5

XI 180 180 ... 1: 1,5 POT / PANI

XII 180 150 10 1: 4 20 XIII 180 150 10 1: 3 XIV 180 150 10 1: 4 XV 180 300 10 1: 4 XVI 180 350 9 1: 4 »i» i 5 22 94056

Table 5. Treatment conditions for products made from solidified PANI / DBSA blend with matrix plastic: in a blender according to method C of the invention.

Experiment with FIX + matrix ratio T mixing- R

Well. teyt.no DBSA plastic PANI / DBSA sections

g g ° C

10 46 I 4 8 PS 1: 3 180 5 13 kΩ

47 EI

48 EI

49 II 48 PS 1: 3 180 5 50 kfl

50 II 4 8 PS 1: 3 180 5 5 kS

15 51 II 3 9 PS 1: 3 180 5 OL

52 II 48 PS 1: 3 180 5 8 kQ

53 III 4 8 PS 1: 3 180 5 50 kQ

54 IV 4 8 PS 1: 4 180 5 10 kQ

55 V 4 8 PS 1: 5 180 5 1 kfl

20 56 EI

57 III 4 8 PVC 1: 3 170 5 250 ΜΩ

58 V 4.5 10 PVC 1: 5 170 5 40 kQ

59 IV 4,5 10 PVC 1: 4 170 5 700 k £ 2 60 III 4 8 SB 1: 3 170 5 50 k £ 2 25 61 IV 48 SB 1: 4 170 10 EIKPL 600 ΚΩ 62 IV 4 8 SB 1: 4 170 10 EIKPL 600 kΩ 63 tissue 61 + 62 4 8 SB 1: 4 170 - 50 ΚΩ 64 VI 48 PS 1: 4 170 5 5 kΩ 65 VII 4 8 PS 1: 4 170 5 12 kΩ 30 66 VIII 4 8 PS 1: 4 170 5 5 kΩ 67 VIII 4 8 SB 1: 4 170 5 3 kÖ: 68 VIII 3 9 SB 1: 4 170 5 20 kΩ

Abbreviations used in the table: PANI = polyaniline, DBSA = 35 dodecylbenzenesulphonic acid (purified grade), PS = polystyrene, T = temperature, R = resistance, LDPE = polyethylene, HDPE = polyethylene, PA = polyamide, SB = styrene-butadiene copolymer, EIKPL pieces.

23 94056 This granular PANI / DBSA product was tested in no. 46, with 30% of that. product granule and the remaining 70% Liquid quality PS-164. The extract thus obtained no. 45 was for the first time completely surface-free and the measured resistance was about 13 5 kQ. The following extrudate made from the same product no. Again, a few surface defects were observed on 47 surfaces. The next experiment was repeated with the screened granule. At this extrudate, surface defects had further increased. From the previous changes, it was concluded that the complex may be hygro-10 scopic and the granule could absorb moisture from the air. Therefore, the next batch of granules was drained directly into a plastic jar and the jar was sealed immediately after the run. The lid of the jar was opened for Blend making only. Test specimens no. 49-52 have been made from this batch and do not show surface defects.

15

Test granules No. 53-63 were made from the above granules. Of the PS-164 alloys Nos. 53-54 (alloy III), the surface is flawless. Em. the conductivities of the samples were measured separately, the conductivities were: No. 53 1 * 10'3 S / cm and no. 54 2 * 10'2 S / cm.

The thermal conductivity of the bodies made by the method of the invention as a function of temperature was studied separately. Figures 1 and 2 show, by way of example, the samples of PS-PANI-DBSA-Blend samples no. 53 and 54 conductivity as a function of temperature. Temperature cycles were 53 for sample 25 25 ° C ----> 120 ° C ---> 25 ° C and for 25 sample 54 25 ° C ---> 150 ° C ----> 25 ° C, heating rate was 1 K / min. As can be seen from the curves, the samples were very stable.

PANI DBSA Batch no. 9 was dried for 3 h at 90 ° C. The dried batch 30 was protonated and tested. Flow traces are present in PS injection molds made from run V. Instead, the resistances in these pieces are lower. The resistances of PVC alloys range from 40 to 700 kQ. The surface of the PVC test pieces is satisfactory. A portion of the batch was "granulated" three to three times according to the method at a temperature of 180 ° C. This was followed by injection molding (fourth melt processing) with polystyrene. The measured resistances were: Sample no. 66 5 kQ and sample no. 67 3 kQ. The samples look good.

24 94056 PANI / DBSA product analysis The polyaniline used (PANI) was in the form of emeraldine base (prepared with Liquid), the PANI / DBSA complex was prepared according to solidification method C above and the polyolefin blends were blended using Neste Oy's polyolefin grades. The purposes of the analysis will be clear from the results obtained.

10 1. Structure of polyaniline

Thermal analysis. Thermal examination showed an endothermic region with a peak at 171 ° C (Figure 3). The endotherm begins as early as 110 ° C. Heat treatment at 130 ° C presumably removed the 15 lower endotherms and moved the maximum to 180 ° C (Figure 4).

X-ray diffraction. X-ray analysis showed a crystal structure in polyaniline (Fig. 5), which clearly decreased after heat treatment (Fig. 6), already showing partial melting of the crystalline region 20. At the same time, however, the heat treatment reduced the dimensions of the crystal (cf. Fig. 5 and Fig. 6), which, together with the increase in melting point observed above, indicates the "compaction effect" of the known crystal of the heat treatment.

25 The combination of these observations was confirmed by heat treatment at 180 ° C: X-ray analysis shows (Fig. 6b) the disappearance of the crystal structure, i.e. the diffraction spectrum shows only the amorphous state. In conclusion, it can be estimated that the endotherm at 170-180 ° C is the melting range of the crystal-30 structure observed in polyaniline.

. 2. Structure of the PANI-DBSA complex

Thermal analysis. Thermal analysis of PANI / DBSA shows a clear exothermic range starting at about 110 ° C and reaching a peak at about 170 ° C (Figure 7). The same exotherm is observed with the PANI / Sulfosoft (commercial DBSA) sample (Figure 8). This exotherm is presumably the heat of complexation of free DBSA. Thermal analysis of the mechanical mixture of components confirmed this (Figure 9). This exotherm allows a quantitative study of complexation. In the past, complexation has always been done in solution or kaa-5 phase or solid phase at room temperature where calorimetry is difficult to monitor. The second exotherm is detectable in all samples at about 220 ° C.

X-ray diffraction. X-ray analysis of the complex revealed 10 comb-like layered crystal structures (Fig. 10 Sulfosoft, Fig. 11 Lab, Fig. 12 Model). 27 Angstroms between layers in the complex correspond well to previous studies in which layered polythiophenes were monitored.

15 3. Workability of the PANI complex

The water-washed complex is conductive, insoluble and melt-untreated. The X-ray spectrum does not show a layer structure. Addition of the washed amount of DBSA to the washed complex provides a conductive, soluble and melt-processable complex with a layered structure in the X-ray spectrum (Figure 13). The 1: 2.5 (PANI / DBSA) complex in Figure 1 is solidified at 80 ° C for 2 h. The layer structure is shown in 26, 571.

The prior art complex comprises the same phenomena as above. No layer structure is visible on X-ray (Figure 14). The product can be processed by adding DBSA. Similarly, a layer structure appears on X-ray.

30 Those X-rays show that there is a clear structural difference between Allied and our solidified product and that they are two different substances.

The PANI complex made by emulsion polymerization also does not show a layer structure (Figure 15). The same is true if the doping is performed in a solvent (ethanol, chloroform) at an elevated temperature.

26 94056 2 b

Figure 16 shows an optical micrograph of PP + Sample 1.

Figure 17 shows an optical micrograph of a product with PP + PANI / DBSA with the light polarizer rotated 10 °.

Figure 18 shows an optical microscopic image of a product with PP + PANI / DBSA with the image aligned with the surface layer.

Figure 19 shows an optical micrograph of the product PP + PANI / DBSA at 100 ° C.

Figure 20 shows an optical micrograph of PP + PANI / DBSA at 150 ° C.

Figure 21 shows an optical micrograph of the product PP + PANI / DBSA after heating at 170 ° C.

Figure 22 shows an optical microscopic image aligned with the HDPE + PANI / DBSA layer.

Figure 23 shows an optical micrograph of HDPE + PANI / DBSA at 220 ° C.

Figure 24 shows an optical micrograph of the product LDPE + PANI / DBSA at elevated temperature.

30

Figure 25 shows another optical micrograph of the product LDPE + PANI / DBSA at elevated temperature.

m 4. Complex-matrix plastic mixtures 35 X-ray diffraction. X-ray diffraction indicates the presence of a layer structure in the mixture (PP Figures 26-27, HDPE Figure 28, LDPE Figure 29).

27 94056

Thermal analysis. Thermal analysis provides indications of partial melting point decrease, shoulder and double-peak (PP Figures 30-31, HDPE Figure 32, LDPE 33). This may indicate the solubility of the complex in the matrix.

j> ·

Claims (16)

94056 A process for producing a solid electrically conductive plastic material, wherein polyaniline or a derivative thereof is brought into contact with an organic sulfonic acid or a derivative thereof, characterized in that the reaction product or mixture of polyaniline or a derivative thereof and an organic sulfonic acid or a derivative thereof is heat-treated with stirring. about +100 to + 250 ° C. Process according to claim 1, characterized in that said reaction product or mixture is stirred during the heat treatment with a screw mixer. Process according to Claim 1 or 2, characterized in that a stoichiometric excess of sulfonic acid or a derivative thereof is used. Process according to one of Claims 1 to 3, characterized in that the heat-treated reaction product 20 or mixture is further mixed with the thermoplastic polymer and melt-processed into a composite material. Process according to any one of the preceding claims, characterized in that the above-mentioned reaction product or mixture is heat-treated at a temperature of about + 150 ° C to + 210 ° C. • · Process according to one of the preceding claims, characterized in that said reaction product or mixture is heat-treated at a pressure of 0.1 to 1000 bar. 30 Process according to one of the preceding claims, characterized in that polyaniline, preferably in the emeraldine base form, is used as the polyaniline or a derivative thereof. 35 Process according to Claim 7, characterized in that the polyaniline used has a molecular weight of at least about 5,000 g / mol, preferably about 15,000 g / mol. 94056 Process according to one of the preceding claims, characterized in that a sulfonic acid, preferably an aromatic sulfonic acid, such as dodecylbenzenesulfonic acid, is used as the sulfonic acid or its derivative. 5 Process according to one of the preceding claims, characterized in that the weight ratio: (polyaniline or a derivative thereof) / (sulfonic acid or a derivative thereof) is between about 0.1-2, preferably about 0.25-1. 10 Process according to one of Claims 4 to 10, characterized in that the thermoplastic polymer is: a homo- or copolymer based on styrene or a derivative thereof or a mixture thereof, a vinyl homopolymer or copolymer or a mixture thereof, an olefin homopolymer or copolymer or a mixture thereof; or a thermoplastic condensation polymer. Process according to one of Claims 4 to 11, characterized in that the weight ratio: (polyaniline or a derivative thereof + sulfonic acid or a derivative thereof) / (thermoplastic polymer) is between about 0.05 and 10. Method according to one of the preceding claims, characterized in that small amounts of thermoplastic polymer are present in the heat treatment. 14. A solid electrically conductive plastic material prepared by contacting a polyaniline or a derivative thereof with an organic sulfonic acid or a derivative thereof, characterized in that the polyaniline or a derivative thereof and an organic sulfonic acid or a derivative thereof are reacted by stirring in a mixing device at a temperature of about + 100 - + 250 ° C. 35 Plastic material according to Claim 14, characterized in that it is in the form of a dry powder or granulate. 94056 Plastic material according to claim 14 or 15, characterized in that said reaction product is mixed with a thermoplastic polymer and melt-treated with it into a composite material. 5