CA1156246A - Pyrolysis of aromatic compounds and resultant products - Google Patents
Pyrolysis of aromatic compounds and resultant productsInfo
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- CA1156246A CA1156246A CA000365397A CA365397A CA1156246A CA 1156246 A CA1156246 A CA 1156246A CA 000365397 A CA000365397 A CA 000365397A CA 365397 A CA365397 A CA 365397A CA 1156246 A CA1156246 A CA 1156246A
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- 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
- H01B1/04—Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors mainly consisting of carbon-silicon compounds, carbon or silicon
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D311/00—Heterocyclic compounds containing six-membered rings having one oxygen atom as the only hetero atom, condensed with other rings
- C07D311/02—Heterocyclic compounds containing six-membered rings having one oxygen atom as the only hetero atom, condensed with other rings ortho- or peri-condensed with carbocyclic rings or ring systems
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Abstract
PYROLYSIS OF AROMATIC COMPOUNDS
AND RESULTANT PRODUCTS
ABSTRACT
This invention relates to a process for the production of carbon-containing materials by pyrolysing aromatic organic compounds and collecting carbon-containing reaction products of the pyrolysis. The improvement resides in using aromatic organic compounds having fused aromatic rings which form free radicals at the peri positions, for example, by elimination of a stable inorganic gas. The products of the pyrolysis include electrically conductive inert films. Pyrolysis in the presence of suitable inorganic materials leads to products with somewhat modified properties, for example addition of niobium pentachloride leads to the production of superconducting materials while addition of sulfur allows production of compounds useful as constituents in organic electrically conductive materials.
AND RESULTANT PRODUCTS
ABSTRACT
This invention relates to a process for the production of carbon-containing materials by pyrolysing aromatic organic compounds and collecting carbon-containing reaction products of the pyrolysis. The improvement resides in using aromatic organic compounds having fused aromatic rings which form free radicals at the peri positions, for example, by elimination of a stable inorganic gas. The products of the pyrolysis include electrically conductive inert films. Pyrolysis in the presence of suitable inorganic materials leads to products with somewhat modified properties, for example addition of niobium pentachloride leads to the production of superconducting materials while addition of sulfur allows production of compounds useful as constituents in organic electrically conductive materials.
Description
PYROLYSIS OF AROMATIC COMPOUNDS
AND RESULTANT PRODUCTS
Background of the Invention 1. Field of the Invention This invention relates to organic chemical synthesis and, more particularly, to processes involving pyrolysis of aromatic compounds.
AND RESULTANT PRODUCTS
Background of the Invention 1. Field of the Invention This invention relates to organic chemical synthesis and, more particularly, to processes involving pyrolysis of aromatic compounds.
2. Art Background Conductive carbon compositions such as graphite play an extremely important role in industrial products and processes. Because of its significant mechanical and electrical prop~rties, graphite is extensively utilized.
For this reason, research on the production of graphite, or compounds with the electrical or mechanical properties of graphite, has been intensiv0. For example, a plethora of organic compounds has been pyrolyzed in an attempt to produce carbon compositions with useful properties, e.g., high conductivity. (See E. Fitzer et al, The Chemistry and Physics _ Carbon, 7, 237 (1971) for a review of this work.) The interest in electrical properties such as found in graphite has also spurred research concerning organic conductors. These organic compounds conduct through an ionic crystal composed of organic anions and cations. Organic conductors such as tetrathiafulvalenium-tetracyanoquinodimethanide have shown promising conductivities, i.e., conductivities approaching 1030hm-lCm-l Summary of the Invention By pyrolysis of appropriately chosen aromatic compounds, materials having good electrical properties, e.g., relatively high conductivity are producible. The appropriate aromatic compounds are those having fused rings which, when heated, produce free radicals on adjacent peri positions of the aromatic compound by, for example, eliminating a stable inorganic gas from these positions.
~For the purposes of this application, carbon oxides such as carbon monoxide and carbon dioxide are considered stable inorganic gases.) When a heated object is placed in the effluent from this pyrolysis reaction, it is coated by a conductive film. This film, although analyzed as essentially entirely carbon (i.e.,~ 99~), has an x-ray crystallographic diffraction behavior which is not in-dicative of a graphitic structure. In fact, d-spacings obtained by electron diffraction resemble those of diamond.
The films, nevertheless, have high relative conductivity, e.g. 250 ohm lcm 1, are extremely adherent to materials suah as ceramics, glass and metals, e.g., tantalum, and are inert to most corrosive compounds. Thus, the films are useful both as an electrical conductor, for example, as a conducting film on an optical fibre, or as a film protection against corrosion. ~dditionally, when this pyrolysis is performed in the presence of an added material such as sulfur, compounds containing the added material that are useful as constituents in organic conductors are produced.
Thus, according to one aspect of the invention there is provided a process for the production of a carbon containing body comprising the steps of pyrolyzing a carbon containing compound and collecting a reaction product from said pyrolysis characterized in that said carbon containing compound comprises an aromatic organic compound having fused aeomatic rings which, due to the pyrolysis at a temperature in the range from 700 to 1200 degrees C, forms free radicals at the peri positions o said fused rings, wherein said free radicals are formed due to said pyrolysis through the production of a stable inorganic gas by removal of a substituent from said peri positions of said compound without the destruction of said fused aromatic rings, and wherein said reaction product is ,s~ ~
1 1562~6 - 2a -capable of being deposited on a heated substrate.
According to another aspect of the invention there :is provided a product formed by the process comprising the steps of pyrolyzing a carbon containing compound and collecting a reaction product from said pyrolysis characterized in that said carbon containing compound comprises an aromatic organic compound having fused aromatic rings which, due to said pyrolysis at a tem-per3ture in the range from 700 to 1200 degrees C, forms free radicals at the peri positions of said fused rings of said carbon containing compound, wherein said free radicals are formed due to said pyrolysis through the production of a stable inorganic gas by removal of a substituent from said peri positions of said compound without the destruction of said fused aromatic rings, and wherein said reaction product is capable of being deposited on a heated substrate.
The properties of the pyrolytically produced materials are also modifiable by including an appropriate additive with the initial reactant. For example, a superconducting material having a critical temperature of about 12 degrees K is produced when niobium pentachloride is included dur-ing the pyrolysis of 3, 4, 9, 10-perylenetetracarboxylic dianhydride.
Brief Description of the Drawinq FIG. 1 is a schematic illustration of an apparatus useful for practicing the subject invention; and FIG. 2 is a representation useful in defining appropriate reactants.
., f Detailed Description Techniques for the pyrolysis of organic compounds are well known. Although the subject invention is not limited to any one particular technique, in a preferred embodiment, an apparatus shown in FIG. 1 is utilized. The organic compound to be pyrolyzed, 1, (FIG. 1), is placed in reaction tube, 10. For convenience, to maintain the reactant in the desired position a layer of porcelain rings, 30, and a layer of quartz wool, 31, are also inserted into the tube after the reactant. The articles to be coated, 9, with the product of the pyrolysis reaction are placed in the reaction tube downstream from the reactants. Reaction tube, 10, is placed in tube furnace, 5, with the tube section, 11, outside the furnace.
After the furnace has been heated to the pyrolysis temperature, the tube is moved so that section, 11, containing the reactant, is inside the furnace. The reaction temperature utilized should be equal to or exceed the decomposition temperature of the organic compound reactant. Typically, this temperature is in the range of from 700 degrees C to 900 degrees C. Temperatures greater than 1200 degrees C are not desirable, since common containers such as quartz begin to soften, and temperatures below 700 degrees C are usually inadequate to induce decomposition.
The organic compound to be pyrolyzed should be an aromatic compound having a nucleus containing fused aromatic rings where the aromatic nucleus is arranged to have peri positions. Additionally, upon pyrolysis, these compounds should undergo a change to produce free radicals at the peri positions, i.e., producing a free radical at positions 20 and 22 and/or 15 and 14 (FIG. 2), e.g., by eliminating an inorganic gas from adjacent ~ positions, - i.e., from the positions marked 20 and 22 and/or the positions marked 15 and 14 in FIG. 2. For example, when
For this reason, research on the production of graphite, or compounds with the electrical or mechanical properties of graphite, has been intensiv0. For example, a plethora of organic compounds has been pyrolyzed in an attempt to produce carbon compositions with useful properties, e.g., high conductivity. (See E. Fitzer et al, The Chemistry and Physics _ Carbon, 7, 237 (1971) for a review of this work.) The interest in electrical properties such as found in graphite has also spurred research concerning organic conductors. These organic compounds conduct through an ionic crystal composed of organic anions and cations. Organic conductors such as tetrathiafulvalenium-tetracyanoquinodimethanide have shown promising conductivities, i.e., conductivities approaching 1030hm-lCm-l Summary of the Invention By pyrolysis of appropriately chosen aromatic compounds, materials having good electrical properties, e.g., relatively high conductivity are producible. The appropriate aromatic compounds are those having fused rings which, when heated, produce free radicals on adjacent peri positions of the aromatic compound by, for example, eliminating a stable inorganic gas from these positions.
~For the purposes of this application, carbon oxides such as carbon monoxide and carbon dioxide are considered stable inorganic gases.) When a heated object is placed in the effluent from this pyrolysis reaction, it is coated by a conductive film. This film, although analyzed as essentially entirely carbon (i.e.,~ 99~), has an x-ray crystallographic diffraction behavior which is not in-dicative of a graphitic structure. In fact, d-spacings obtained by electron diffraction resemble those of diamond.
The films, nevertheless, have high relative conductivity, e.g. 250 ohm lcm 1, are extremely adherent to materials suah as ceramics, glass and metals, e.g., tantalum, and are inert to most corrosive compounds. Thus, the films are useful both as an electrical conductor, for example, as a conducting film on an optical fibre, or as a film protection against corrosion. ~dditionally, when this pyrolysis is performed in the presence of an added material such as sulfur, compounds containing the added material that are useful as constituents in organic conductors are produced.
Thus, according to one aspect of the invention there is provided a process for the production of a carbon containing body comprising the steps of pyrolyzing a carbon containing compound and collecting a reaction product from said pyrolysis characterized in that said carbon containing compound comprises an aromatic organic compound having fused aeomatic rings which, due to the pyrolysis at a temperature in the range from 700 to 1200 degrees C, forms free radicals at the peri positions o said fused rings, wherein said free radicals are formed due to said pyrolysis through the production of a stable inorganic gas by removal of a substituent from said peri positions of said compound without the destruction of said fused aromatic rings, and wherein said reaction product is ,s~ ~
1 1562~6 - 2a -capable of being deposited on a heated substrate.
According to another aspect of the invention there :is provided a product formed by the process comprising the steps of pyrolyzing a carbon containing compound and collecting a reaction product from said pyrolysis characterized in that said carbon containing compound comprises an aromatic organic compound having fused aromatic rings which, due to said pyrolysis at a tem-per3ture in the range from 700 to 1200 degrees C, forms free radicals at the peri positions of said fused rings of said carbon containing compound, wherein said free radicals are formed due to said pyrolysis through the production of a stable inorganic gas by removal of a substituent from said peri positions of said compound without the destruction of said fused aromatic rings, and wherein said reaction product is capable of being deposited on a heated substrate.
The properties of the pyrolytically produced materials are also modifiable by including an appropriate additive with the initial reactant. For example, a superconducting material having a critical temperature of about 12 degrees K is produced when niobium pentachloride is included dur-ing the pyrolysis of 3, 4, 9, 10-perylenetetracarboxylic dianhydride.
Brief Description of the Drawinq FIG. 1 is a schematic illustration of an apparatus useful for practicing the subject invention; and FIG. 2 is a representation useful in defining appropriate reactants.
., f Detailed Description Techniques for the pyrolysis of organic compounds are well known. Although the subject invention is not limited to any one particular technique, in a preferred embodiment, an apparatus shown in FIG. 1 is utilized. The organic compound to be pyrolyzed, 1, (FIG. 1), is placed in reaction tube, 10. For convenience, to maintain the reactant in the desired position a layer of porcelain rings, 30, and a layer of quartz wool, 31, are also inserted into the tube after the reactant. The articles to be coated, 9, with the product of the pyrolysis reaction are placed in the reaction tube downstream from the reactants. Reaction tube, 10, is placed in tube furnace, 5, with the tube section, 11, outside the furnace.
After the furnace has been heated to the pyrolysis temperature, the tube is moved so that section, 11, containing the reactant, is inside the furnace. The reaction temperature utilized should be equal to or exceed the decomposition temperature of the organic compound reactant. Typically, this temperature is in the range of from 700 degrees C to 900 degrees C. Temperatures greater than 1200 degrees C are not desirable, since common containers such as quartz begin to soften, and temperatures below 700 degrees C are usually inadequate to induce decomposition.
The organic compound to be pyrolyzed should be an aromatic compound having a nucleus containing fused aromatic rings where the aromatic nucleus is arranged to have peri positions. Additionally, upon pyrolysis, these compounds should undergo a change to produce free radicals at the peri positions, i.e., producing a free radical at positions 20 and 22 and/or 15 and 14 (FIG. 2), e.g., by eliminating an inorganic gas from adjacent ~ positions, - i.e., from the positions marked 20 and 22 and/or the positions marked 15 and 14 in FIG. 2. For example, when
3, 4, 9, 10-perylenetetracarboxylic dianhydride is pyrolyzed CO and CO2 are eliminated to at least initially . , .
yield a free radical involving the peri position, e.g., ~ C~O ., ' 5 ~ -_C02tCO~ 1~
of Cb~C~o o~o'C~o Similarly, 1, 4, 5, 8-naphthalenetetracarboxylic dianhydride ~ c~ 0~ 0 ~--oCO2~CO1 1.~1 O~C`O'C~O
elimina,tes CO and CO2 to at least initially yield reactive radicals such as those shown. Although the exact nature of the total reaction processes is unknown the diradical is illustrative of radical intermediates generated during the various pyrolysis reactions.
The pyrolysis reaction produces a low volatility product and a set of products with a higher volatility. To condense the low volatility product the object to be coated must also be heated. An adherent film of the low volatility product does not form on room temperature articles. Typically, temperatures ar`e emp-loyed which are approximately the same as the temperature used for ~ pyrolysis. It is also possible to employ temperatures -, 25 slightly less than the pyrolysis temp,erature. However, generally the temperature employed should be within 100 degrees C of the pyrolysis temperature. A convenient method of heating the articles to be coated, 9, to an appropriate temperature is to place the articles at a position, 8, so that they are inside the heating area of .
.
11~6246 the ~ven. Naturally, to achieve a substantially uniform coating, all s~rfaces of the body, 9, to be coated should be accessible to the decomposition effluent. After the effluent has passed over the articles to be coated, it is vented throuyh port, 16. (It should be noted that this effluent contains the products with higher volatility.) It is possible to collect the more volatile decomposition products by allowing condensation on the reaction tube or other surface outside the heating area before the effluent is vented. For example, if sulfur is mixed with the aromatic compounds used as reactants, the sulfur is incorporated into the compounds to form a higher volatility product having the reactant ring structure plus an additiGnal sulfur~containing ring. For example, compounds such as 1, 4, 5, 8-naphthalenetetracarboxylic dianhydride are mixed with reactants such as sulfur and heated to the temperatures as described previously. The sulfur adds to the aromatic compounds at the points where the gaseous precursor of the compound is expelled to produce compounds such as 1, 4, 5, 8-tetrathianaphthalene.
The more volatile products obtained by this process are useful for applications such as the production of organic compounds that are electrically conducting. To produce a conducting salt, the more volatile product of the subject sulfur addition process is mixed with an appropriate electron acceptor such as TCNQ. (See U. S. Patent 3,162,641 for a description of TCNQ and Torrance, J., Accounts of Chemical Research, 12, 29, (1979) ; for a method of making organic conducting salts.) The lower volatility products when sulfur is added are deposited as described previously and has similar electrical and mechanical properties to films obtained when no sulfur is added.
Additionally, it is possible to change the ,~
electrical properties of the low volatility product film by adding compounds to the reactants. For example, it is possible to add a niobium compound such as niobium pentachlOride to the reactant aromatic compound to produce low volatility product films which exhibit superconductive properties at temperatures of about 12 degrees K. The reaction temperatures utilized are those described above.
The following examples are illustrative of the subject process and products:
Example 1 Approximately 0.25 gram of 1, 4, 5, 8-naphthalenetetracarboxylic dianhydride tpurer than 99~) was pyrolyzed. This pyrolysis was accomplished by using the apparatus illustrated in FIG. 1. In this respect, the dianhydride, 1, was placed in the tube. Porcelain rings, 30, and quartz wool, 31, were sequentially placed in the tube to hold the dianhydride in position and to allow sufficient transfer of heat. Three quartz plates measuring approximately 7cm x 1.5cm x l.Smm thick were placed at position, 8, in the tube. The tube containing the dianhydride was placed so that the dianhydride remained initially outside the heating zone of tube furnace, 5, at room temperature. The tube was then evacuated to a pressure of less than 10 2 Torr. The furnace was then heated to a temperature of about 900 degrees C. When this temperature was achieved, the tube was moved so that the portion of the tube containing the dianhydride was gradually brought into the heating area. This movement of the tube was controlled so that the pressure produced by the onset of decomposition of the dianhydride did not exceed 0.3 Torr. Although this step was not critical, for experimental convenience this gradual decomposition was ; 30 utilized. It was, however, noted that films having a smoother surface were produced when the decomposition rate was controlled.
After the pressure in the system had dropped to its initial reading before decomposition was induced, the tube was removed. The tube was then allowed to cool to room temperature. The glass slides were removed and these slides were essentially uniformly coated with a lustrous , 1 1S~246 metallic appearing mirror surface. In addition, it was noted that the tube was also coated with a similar material. The films obtained were generally in the thickness range of 0.3 to l~m. For these films, ohmmeter S measurements indicated a conductivity of approximately 100 ohms~lcm 1.
~xample 2 The procedure of Example 1 (pyrolysis at 900 degrees C) was followed except that the material used as the reactant was 3, 4, 9, 10-perylenetetracarboxylic dianhydride. Additionally, pyrolysis was performed at both 700 and 800 degrees C. The samples obtained for the procedure using 800 and 900 degrees C temperatures produced similar results. However, the sample pyrolyzed at a temperature of 700 degrees C produced diminished quantities of the desired conducl:ive films.
Example 3 Approximately S grams of sulfur and 1 gram of 1, 4, 5, 8~naphthalenetetracarboxylic dianhydride was placed in the reactant tube as described in Example 1. The procedures as described in Example 1 were followed.
Temperatures at both approximately 800 and 900 degrees C
were utilized. The quartz plates for both temperatures were coated with a film having essentially the same properties as described in Example 1. However, x-ray fluorescence measurements indicated that the material on these quartz plates contained chemically bound sulfur.
Additionally, material condensed on the reaction tube 10 in the area outside the tube furnace 5 downstream from the reactant. This material was scraped off the tube and its constituent parts separated using silica gel thick layer chromotography. Three fractions appeared. One was characterized as an unreacted sulfur, the second was characterized as 1, 5, 4, 8-tetrathianaphthalene by IR
spectroscopy, and the third as 1, 8-dithianaphthalene also by spectroscopy.
11S~2d~6 f`xample 4 .
The tube was filled as described in Example 1 with 100 mg of 3, 4, 9, 10-perylenetetracarboxylic dianhydride and 0.25 gram of niobium pentachloride. The S tube was inserted into the tube furnace with the material outside the heating zone. A vacuum system was attached to the tube, but not activated. The furnace was then heated to 900 degrees C. After the tube reached this temperature, the vacuum system was activated and the tube slowly pulled into the heating zone as described in Example 1. (This procedure was followed because of the high volatility of niobium pentachloride.) X-ray fluorescence measurements of the films indicate that no chlorine had been incorporated into the film. Additionally, electron diffraction measurements indicated that niobium carbide was present in the film. Conductivity measurements done at various temperatures indicated a superconductivity onset (Tc) at approximately 12 degrees K.
yield a free radical involving the peri position, e.g., ~ C~O ., ' 5 ~ -_C02tCO~ 1~
of Cb~C~o o~o'C~o Similarly, 1, 4, 5, 8-naphthalenetetracarboxylic dianhydride ~ c~ 0~ 0 ~--oCO2~CO1 1.~1 O~C`O'C~O
elimina,tes CO and CO2 to at least initially yield reactive radicals such as those shown. Although the exact nature of the total reaction processes is unknown the diradical is illustrative of radical intermediates generated during the various pyrolysis reactions.
The pyrolysis reaction produces a low volatility product and a set of products with a higher volatility. To condense the low volatility product the object to be coated must also be heated. An adherent film of the low volatility product does not form on room temperature articles. Typically, temperatures ar`e emp-loyed which are approximately the same as the temperature used for ~ pyrolysis. It is also possible to employ temperatures -, 25 slightly less than the pyrolysis temp,erature. However, generally the temperature employed should be within 100 degrees C of the pyrolysis temperature. A convenient method of heating the articles to be coated, 9, to an appropriate temperature is to place the articles at a position, 8, so that they are inside the heating area of .
.
11~6246 the ~ven. Naturally, to achieve a substantially uniform coating, all s~rfaces of the body, 9, to be coated should be accessible to the decomposition effluent. After the effluent has passed over the articles to be coated, it is vented throuyh port, 16. (It should be noted that this effluent contains the products with higher volatility.) It is possible to collect the more volatile decomposition products by allowing condensation on the reaction tube or other surface outside the heating area before the effluent is vented. For example, if sulfur is mixed with the aromatic compounds used as reactants, the sulfur is incorporated into the compounds to form a higher volatility product having the reactant ring structure plus an additiGnal sulfur~containing ring. For example, compounds such as 1, 4, 5, 8-naphthalenetetracarboxylic dianhydride are mixed with reactants such as sulfur and heated to the temperatures as described previously. The sulfur adds to the aromatic compounds at the points where the gaseous precursor of the compound is expelled to produce compounds such as 1, 4, 5, 8-tetrathianaphthalene.
The more volatile products obtained by this process are useful for applications such as the production of organic compounds that are electrically conducting. To produce a conducting salt, the more volatile product of the subject sulfur addition process is mixed with an appropriate electron acceptor such as TCNQ. (See U. S. Patent 3,162,641 for a description of TCNQ and Torrance, J., Accounts of Chemical Research, 12, 29, (1979) ; for a method of making organic conducting salts.) The lower volatility products when sulfur is added are deposited as described previously and has similar electrical and mechanical properties to films obtained when no sulfur is added.
Additionally, it is possible to change the ,~
electrical properties of the low volatility product film by adding compounds to the reactants. For example, it is possible to add a niobium compound such as niobium pentachlOride to the reactant aromatic compound to produce low volatility product films which exhibit superconductive properties at temperatures of about 12 degrees K. The reaction temperatures utilized are those described above.
The following examples are illustrative of the subject process and products:
Example 1 Approximately 0.25 gram of 1, 4, 5, 8-naphthalenetetracarboxylic dianhydride tpurer than 99~) was pyrolyzed. This pyrolysis was accomplished by using the apparatus illustrated in FIG. 1. In this respect, the dianhydride, 1, was placed in the tube. Porcelain rings, 30, and quartz wool, 31, were sequentially placed in the tube to hold the dianhydride in position and to allow sufficient transfer of heat. Three quartz plates measuring approximately 7cm x 1.5cm x l.Smm thick were placed at position, 8, in the tube. The tube containing the dianhydride was placed so that the dianhydride remained initially outside the heating zone of tube furnace, 5, at room temperature. The tube was then evacuated to a pressure of less than 10 2 Torr. The furnace was then heated to a temperature of about 900 degrees C. When this temperature was achieved, the tube was moved so that the portion of the tube containing the dianhydride was gradually brought into the heating area. This movement of the tube was controlled so that the pressure produced by the onset of decomposition of the dianhydride did not exceed 0.3 Torr. Although this step was not critical, for experimental convenience this gradual decomposition was ; 30 utilized. It was, however, noted that films having a smoother surface were produced when the decomposition rate was controlled.
After the pressure in the system had dropped to its initial reading before decomposition was induced, the tube was removed. The tube was then allowed to cool to room temperature. The glass slides were removed and these slides were essentially uniformly coated with a lustrous , 1 1S~246 metallic appearing mirror surface. In addition, it was noted that the tube was also coated with a similar material. The films obtained were generally in the thickness range of 0.3 to l~m. For these films, ohmmeter S measurements indicated a conductivity of approximately 100 ohms~lcm 1.
~xample 2 The procedure of Example 1 (pyrolysis at 900 degrees C) was followed except that the material used as the reactant was 3, 4, 9, 10-perylenetetracarboxylic dianhydride. Additionally, pyrolysis was performed at both 700 and 800 degrees C. The samples obtained for the procedure using 800 and 900 degrees C temperatures produced similar results. However, the sample pyrolyzed at a temperature of 700 degrees C produced diminished quantities of the desired conducl:ive films.
Example 3 Approximately S grams of sulfur and 1 gram of 1, 4, 5, 8~naphthalenetetracarboxylic dianhydride was placed in the reactant tube as described in Example 1. The procedures as described in Example 1 were followed.
Temperatures at both approximately 800 and 900 degrees C
were utilized. The quartz plates for both temperatures were coated with a film having essentially the same properties as described in Example 1. However, x-ray fluorescence measurements indicated that the material on these quartz plates contained chemically bound sulfur.
Additionally, material condensed on the reaction tube 10 in the area outside the tube furnace 5 downstream from the reactant. This material was scraped off the tube and its constituent parts separated using silica gel thick layer chromotography. Three fractions appeared. One was characterized as an unreacted sulfur, the second was characterized as 1, 5, 4, 8-tetrathianaphthalene by IR
spectroscopy, and the third as 1, 8-dithianaphthalene also by spectroscopy.
11S~2d~6 f`xample 4 .
The tube was filled as described in Example 1 with 100 mg of 3, 4, 9, 10-perylenetetracarboxylic dianhydride and 0.25 gram of niobium pentachloride. The S tube was inserted into the tube furnace with the material outside the heating zone. A vacuum system was attached to the tube, but not activated. The furnace was then heated to 900 degrees C. After the tube reached this temperature, the vacuum system was activated and the tube slowly pulled into the heating zone as described in Example 1. (This procedure was followed because of the high volatility of niobium pentachloride.) X-ray fluorescence measurements of the films indicate that no chlorine had been incorporated into the film. Additionally, electron diffraction measurements indicated that niobium carbide was present in the film. Conductivity measurements done at various temperatures indicated a superconductivity onset (Tc) at approximately 12 degrees K.
Claims (16)
1. A process for the production of a carbon containing body comprising the steps of pyrolyzing a carbon containing compound and collecting a reaction product from said pyrolysis CHARACTERIZED IN THAT
said carbon containing compound comprises an aromatic organic compound having fused aromatic rings which, due to the pyrolysis at a temperature in the range from 700 to 1200 degrees C, forms free radicals at the peri positions of said fused rings, wherein said free radicals are formed due to said pyrolysis through the production of a stable inorganic gas by removal of a substituent from said peri positions of said compound without the destruction of said fused aromatic rings, and wherein said reaction product is capable of being deposited on a heated substrate.
said carbon containing compound comprises an aromatic organic compound having fused aromatic rings which, due to the pyrolysis at a temperature in the range from 700 to 1200 degrees C, forms free radicals at the peri positions of said fused rings, wherein said free radicals are formed due to said pyrolysis through the production of a stable inorganic gas by removal of a substituent from said peri positions of said compound without the destruction of said fused aromatic rings, and wherein said reaction product is capable of being deposited on a heated substrate.
2. The process of claim 1 wherein said pyrolysis is performed in the absence of an additional agent which reacts with said free radicals.
3. The process of claim 1 wherein elemental sulfur is present during said pyrolysis of said carbon containing compound.
4. The process of claim 1 or 2 or 3 wherein said carbon containing compound is 3,4,9,10-perylenetetracarboxylic dianhydride.
5. The process of claim 1 or 2 or 3 wherein said free radicals are formed by elimination of a stable inorganic gas.
6. The process of claim 1 wherein a niobium compound is present during said pyrolysis.
7. A process for the production of a carbon containing body comprising the steps of pyrolyzing a carbon containing compound and collecting a reaction product froln said pyrolysis CHARACTERIZED IN THAT
said carbon containing compound comprises an aromatic organic compound having fused aromatic rings which, due to said pyrolysis at a temperature in the range from 700 to 1200 degrees C, forms free radicals at the peri positions of said fused rings of said carbon containing compound, wherein said free radicals are formed due to said pyrolysis through the production of a stable inorganic gas by removal of a substituent from said peri positions of said compound without the destruction of said fused aromatic rings, wherein said pyrolysis is performed in the absence of an additional agent which reacts with said free radicals and wherein said reaction product is capable of being deposited on a heated substrate.
said carbon containing compound comprises an aromatic organic compound having fused aromatic rings which, due to said pyrolysis at a temperature in the range from 700 to 1200 degrees C, forms free radicals at the peri positions of said fused rings of said carbon containing compound, wherein said free radicals are formed due to said pyrolysis through the production of a stable inorganic gas by removal of a substituent from said peri positions of said compound without the destruction of said fused aromatic rings, wherein said pyrolysis is performed in the absence of an additional agent which reacts with said free radicals and wherein said reaction product is capable of being deposited on a heated substrate.
8. The process of claim 7 wherein said carbon containing compound is 3,4,9,10-perylenetetracarboxylic dianhydride.
9. A product formed by the process comprising the steps of pyrolyzing a carbon containing compound and collecting a reaction product from said pyrolysis CHARACTERIZED IN THAT
said carbon containing compound comprises an aromatic organic compound having fused aromatic rings which, due to said pyrolysis at a temperature in the range from 700 to 1200 degrees C, forms free radicals at the peri positions of said fused rings of said carbon containing compound, wherein said free radicals are formed due to said pyrolysis through the production of a stable inorganic gas by removal of a substituent from said peri positions of said compound without the destruction of said fused aromatic rings, and wherein said reaction product is capable of being deposited on a heated substrate.
said carbon containing compound comprises an aromatic organic compound having fused aromatic rings which, due to said pyrolysis at a temperature in the range from 700 to 1200 degrees C, forms free radicals at the peri positions of said fused rings of said carbon containing compound, wherein said free radicals are formed due to said pyrolysis through the production of a stable inorganic gas by removal of a substituent from said peri positions of said compound without the destruction of said fused aromatic rings, and wherein said reaction product is capable of being deposited on a heated substrate.
10. The product of claim 9 wherein said free radicals are formed by elimination of a stable inorganic gas.
11. A product formed by the process comprising the steps of pyrolyzing a carbon containing compound and collecting a reaction product from said pyrolysis CHARACTERIZED IN THAT
said carbon containing compound comprises an aromatic organic compound having fused aromatic rings which, due to said pyrolysis at a temperature in the range from 700 to 1200 degrees C, forms free radicals at the peri positions of said fused rings of said carbon containing compound, wherein said free radicals are formed due to said pyrolysis through the production of a stable inorganic gas by removal of a substituent from said peri positions of said compound without the destruction of said fused aromatic rings, wherein said pyrolysis is performed in the absence of an additional agent which reacts with said free radicals and wherein said reaction product is capable of being deposited on a heated substrate.
said carbon containing compound comprises an aromatic organic compound having fused aromatic rings which, due to said pyrolysis at a temperature in the range from 700 to 1200 degrees C, forms free radicals at the peri positions of said fused rings of said carbon containing compound, wherein said free radicals are formed due to said pyrolysis through the production of a stable inorganic gas by removal of a substituent from said peri positions of said compound without the destruction of said fused aromatic rings, wherein said pyrolysis is performed in the absence of an additional agent which reacts with said free radicals and wherein said reaction product is capable of being deposited on a heated substrate.
12. The product of claim 11 wherein said free radicals are formed by elimination of a stable inorganic gas.
13. A process for the production of a carbon containing body comprising the steps of pyrolyzing a carbon containing compound and collecting a reaction product from said pyrolysis CHARACTERIZED IN THAT
said carbon containing compound comprises an aromatic organic compound having fused aromatic rings which, due to said pyrolysis at a temperature in the range from 700 to 1200 degrees C, forms free radicals at the peri positions of said fused rings of said carbon containing compound, wherein said free radicals are formed due to said pyrolysis through the production of a stable inorganic gas by removal of a substituent from said peri positions of said compound without the destruction of said fused aromatic rings, wherein sulfur is the only agent present during said pyrolysis step which reacts with said radicals, and wherein said collected reaction product is a high volatility product.
said carbon containing compound comprises an aromatic organic compound having fused aromatic rings which, due to said pyrolysis at a temperature in the range from 700 to 1200 degrees C, forms free radicals at the peri positions of said fused rings of said carbon containing compound, wherein said free radicals are formed due to said pyrolysis through the production of a stable inorganic gas by removal of a substituent from said peri positions of said compound without the destruction of said fused aromatic rings, wherein sulfur is the only agent present during said pyrolysis step which reacts with said radicals, and wherein said collected reaction product is a high volatility product.
14. The process of claim 13 wherein said compound is 3,4,9,10-perylenetetracarboxylic dianhydride.
15. The process of claim 13 wherein said free radicals are formed by elimination of a stable inorganic gas.
16. A process for the production of a carbon containing body comprising the steps of pyrolyzing a carbon containing compound and collecting a reaction product from said pyrolysis CHARACTERIZED IN THAT
said carbon containing compound comprises an aromatic organic compound having fused aromatic rings which, due to said pyrolysis at a temperature in the range from 700 to 1200 degrees C, forms free radicals at the peri positions of said fused rings of said carbon containing compound, wherein said free radicals are formed due to said pyrolysis through the production of a stable inorganic gas by removal of a substituent from said peri positions of said compound without the destruction of said fused aromatic rings, and wherein niobium is the only agent present during said pyrolysis step which reacts with said radicals.
said carbon containing compound comprises an aromatic organic compound having fused aromatic rings which, due to said pyrolysis at a temperature in the range from 700 to 1200 degrees C, forms free radicals at the peri positions of said fused rings of said carbon containing compound, wherein said free radicals are formed due to said pyrolysis through the production of a stable inorganic gas by removal of a substituent from said peri positions of said compound without the destruction of said fused aromatic rings, and wherein niobium is the only agent present during said pyrolysis step which reacts with said radicals.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US10415979A | 1979-12-17 | 1979-12-17 | |
| US104,159 | 1979-12-17 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1156246A true CA1156246A (en) | 1983-11-01 |
Family
ID=22298954
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000365397A Expired CA1156246A (en) | 1979-12-17 | 1980-11-25 | Pyrolysis of aromatic compounds and resultant products |
Country Status (5)
| Country | Link |
|---|---|
| JP (1) | JPS5696711A (en) |
| CA (1) | CA1156246A (en) |
| DE (1) | DE3047516A1 (en) |
| GB (1) | GB2065652B (en) |
| NL (1) | NL8006820A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4510077A (en) * | 1983-11-03 | 1985-04-09 | General Electric Company | Semiconductive glass fibers and method |
-
1980
- 1980-11-25 CA CA000365397A patent/CA1156246A/en not_active Expired
- 1980-12-16 NL NL8006820A patent/NL8006820A/en not_active Application Discontinuation
- 1980-12-16 GB GB8040184A patent/GB2065652B/en not_active Expired
- 1980-12-17 DE DE19803047516 patent/DE3047516A1/en not_active Withdrawn
- 1980-12-17 JP JP17732480A patent/JPS5696711A/en active Pending
Also Published As
| Publication number | Publication date |
|---|---|
| GB2065652A (en) | 1981-07-01 |
| JPS5696711A (en) | 1981-08-05 |
| NL8006820A (en) | 1981-07-16 |
| GB2065652B (en) | 1984-02-29 |
| DE3047516A1 (en) | 1981-09-17 |
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