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Claims  |
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Having thus described the invention, what we claim as new, and desire to
secure by Letters Patent is:
1. A water-soluble, electrically conductive composition of matter capable
of forming a stable 5 wt. % solution in water, comprising a polyacid
wherein said polyacid is selected from the group consisting of
poly(acrylic acid), poly(methacrylic acid), poly(styrene sulfonic acid),
poly(vinylsulfonic acid), poly(styrene boric acid), poly(vinyl boric
acid), poly(vinyl sulfuric acid), poly(styrene phosphonic acid),
poly(vinyl phosphoric acid), poly(styrene phosphonic acid) and poly(vinyl
phosphonic acid), and a polymer comprising at least one conjugated region
composed of repeating units which contain a conjugated basic atom wherein
said polymer is selected from the group consisting of substituted and
unsubstituted homopolymers and copolymers of aniline, thiophene, pyrrole,
and p-phenylene sulfide,
wherein the number of acidic groups in said polyacid exceeds the number of
protonatable basic atoms in said polymer.
2. A composition of matter according to claim 1 wherein said polyacid is
poly(styrene sulfonic acid).
3. A composition of matter according to claim 1 wherein said polyacid is
poly(vinyl sulfonic acid).
4. A composition of matter according to claim 1 wherein said polyacid is
poly(acrylic acid).
5. A composition of matter according to claim 1 wherein said polyacid is
poly(methacrylic acid).
6. A composition of matter according to claim 1 wherein said polyacid is
poly(vinyl phosphonic acid).
7. A composition of matter according to claim 1 wherein said polyacid is
poly(styrene phosphonic acid).
8. A composition of matter according to claim 1 wherein said polymer is
polyaniline.
9. A composition of matter according to claim 8 wherein said polyacid is
poly(styrene sulfonic acid).
10. A composition of matter according to claim 1 wherein said polymer is
polythiophene.
11. A composition of matter according to claim 1 wherein said polymer is
polypyrrole.
12. A composition of matter according to claim 1 wherein said polymer is
poly(p-phenylene sulfide).
13. A composition of matter according to claim 1 wherein said aniline is
substituted with one or more substituents selected from the group
consisting of alkyl, alkoxyalkyl, and alkoxy groups containing 1 to 30
carbon atoms.
14. A composition of matter according to claim 1 wherein said thiophene is
substituted with one or more substituents selected from the group
consisting of alkyl, alkoxyalkyl, and alkoxy groups containing 1 to 30
carbon atoms.
15. A composition of matter according to claim 1 wherein said pyrrole is
substituted with one or more substituents selected from the group
consisting of alkyl, alkoxyalkyl, and alkoxy groups containing 1 to 30
carbon atoms.
16. A composition of matter according to claim 1 wherein said p-phenylene
sulfide is substituted with one or more substituents selected from the
group consisting of alkyl, alkoxyalkyl, and alkoxy groups containing 1 to
30 carbon atoms.
17. A composition of matter according to claim 1 wherein said polymer is
cross-linkable.
18. An aqueous solution comprising a composition of matter according to
claim 1.
19. An aqueous solution according to claim 18 comprising dissolved therein
at least about 5 wt. % of said composition of matter.
20. An aqueous solution according to claim 18 comprising dissolved therein
about 5 wt. % to about 10 wt. % of said composition of matter.
21. An aqueous solution according to claim 18 comprising dissolved therein
about 5 wt. % of said composition of matter.
22. A solution according to claim 18 wherein said polyacid is poly(styrene
sulfonic acid).
23. A solution according to claim 18 wherein said polyacid is poly(vinyl
sulfonic acid).
24. A solution according to claim 18 wherein said polyacid is poly(acrylic
acid).
25. A solution according to claim 18 wherein said polyacid is
poly(methacrylic acid).
26. A solution according to claim 18 wherein said polyacid is poly(vinyl
phosphonic acid).
27. A solution according to claim 18 wherein said polyacid is poly(styrene
phosphonic acid).
28. A solution according to claim 18 wherein said polymer is polyaniline.
29. A solution according to claim 18 wherein said polyacid is poly(styrene
sulfonic acid).
30. A solution according to claim 18 wherein said polymer is polythiophene.
31. A solution according to claim 18 wherein said polymer is polypyrrole.
32. A solution according to claim 18 wherein said polymer is
poly(p-phenylene sulfide).
33. A solution according to claim 18 wherein said aniline is substituted
with one or more substituents selected from the group consisting of alkyl,
alkoxyalkyl, and alkoxy groups containing 1 to 30 carbon atoms.
34. A solution according to claim 18 wherein said thiophene is substituted
with one or more substituents selected from the group consisting of alkyl,
alkoxyalkyl, and alkoxy groups containing 1 to 30 carbon atoms.
35. A solution according to claim 18 wherein said pyrrole is substituted
with one or more substituents selected from the group consisting of alkyl,
alkoxyalkyl, and alkoxy groups containing 1 to 30 carbon atoms.
36. A solution according to claim 18 wherein said p-phenylene sulfide is
substituted with one or more substituents selected from the group
consisting of alkyl, alkoxyalkyl, and alkoxy groups containing 1 to 30
carbon atoms.
37. A solution according to claim 18 wherein said polymer is
cross-linkable.
38. A water-insoluble, electrically conductive composition of matter
comprising a polyacid selected from the group consisting of poly(acrylic
acid), (methacrylic acid), poly(styrene sulfonic acid), poly(vinylsulfonic
acid), poly(styrene boric acid), poly(vinyl boric acid), poly(vinyl
sulfuric acid), poly(styrene phosphoric acid), poly(vinyl phosphoric
acid), poly(styrene phosphonic acid) and poly(vinyl phosphonic acid), and
a polymer comprising at least one conjugated region composed of repeating
units which contain a conjugated basic atom, wherein said polymer is
selected from the group consisting of substituted and unsubstituted
homopolymers and copolymers of aniline, thiophene, pyrrole, and
p-phenylene sulfide,
wherein the number of acidic groups in said polyacid exceeds the number of
protonatable basic atoms in said polymer,
wherein said composition of matter is capable of forming a stable 5 wt. %
solution in water when said polymer is not cross-linked, wherein said
polymer is cross-linked.
39. A composition of matter according to claim 38 wherein said polymer is
selected from the group consisting of polymers of aniline, thiophene,
pyrrole, and p-phenylene sulfide.
40. A composition of matter according to claim 39 wherein said polymer is
polyaniline.
41. A composition of matter according to claim 38 wherein said polyacid is
poly(styrene sulfonic acid).
42. A composition of matter according to claim 41 wherein said polymer is
polyaniline.
43. A water-soluble, electrically conductive composition of matter capable
of forming a stable 5 wt. % solution in water, and comprising a polyacid
and a conjugated polymer composed of repeating units which contain a
conjugated basic atom, wherein the number of acidic groups in said
polyacid exceeds the number of protonatable basic atoms in said polymer,
which composition of matter is the product of the process comprising
forming an aqueous solution of one or more monomers selected from the
group consisting of substituted and unsubstituted aniline, thiophene,
pyrrole, and mercaptophenol, and a polyacid selected from the group
consisting of poly(acrylic acid), poly(methacrylic acid), poly(styrene
sulfonic acid), poly(vinylsulfonic acid), poly(styrene boric acid),
poly(vinyl boric acid), poly(vinyl sulfuric acid), poly(styrene phosphoric
acid), poly(vinyl phosphoric acid), poly(styrene phosphonic acid) and
poly(vinyl phosphonic acid), wherein the number of acid groups on said
polyacid exceeds the number of said basic atoms, and polymerizing the
monomer while controlling the rate of initiation and the rate of
propagation of said polymerization such that the polymerization forms said
composition of matter in said solution.
44. A composition of matter according to claim 43 wherein said polyacid is
poly(styrene sulfonic acid).
45. A composition of matter according to claim 43 wherein said polyacid is
poly(vinyl sulfonic acid).
46. A composition of matter according to claim 43 wherein said polyacid is
poly(acrylic acid).
47. A composition of matter according to claim 43 wherein said polyacid is
poly(methacrylic acid).
48. A composition of matter according to claim 43 wherein said polyacid is
poly(vinyl phosphonic acid).
49. A composition of matter according to claim 43 wherein said polyacid is
poly(styrene phosphonic acid).
50. A composition of matter according to claim 43 wherein said polymer is
polyaniline.
51. A composition of matter according to claim 43 wherein said polyacid is
poly(styrene sulfonic acid).
52. A composition of matter according to claim 43 wherein said polymer is
polythiophene.
53. A composition of matter according to claim 43 wherein said polymer is
polypyrrole.
54. A composition of matter according to claim 43 wherein said polymer is
poly(p-phenylene sulfide).
55. A composition of matter according to claim 43 wherein said aniline is
substituted with one or more substituents selected from the group
consisting of alkyl, alkoxyalkyl, and alkoxy groups containing 1 to 30
carbon atoms.
56. A composition of matter according to claim 43 wherein said thiophene is
substituted with one or more substituents selected from the group
consisting of alkyl, alkoxyalkyl, and alkoxy groups containing 1 to 30
carbon atoms.
57. A composition of matter according to claim 43 wherein said pyrrole is
substituted with one or more substituents selected from the group
consisting of alkyl, alkoxyalkyl, and alkoxy group containing 1 to 30
carbon atoms.
58. A composition of matter according to claim 43 wherein said p-phenylene
sulfide is substituted with one or more substituents selected from the
group consisting of alkyl, alkoxyalkyl, and alkoxy groups containing 1 to
30 carbon atoms.
59. A composition of matter according to claim 43 wherein said polymer is
cross-linkable. |
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Claims |
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Description |
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BACKGROUND OF THE INVENTION
The present invention relates to novel electrically conductive polymer
complexes, electrically conductive resists, uses thereof and structures
fabricated therewith. More particularly, this invention relates to
water-soluble, electrically conductive substituted and unsubstituted
polymer complexes and their use as, inter alia, electrical discharge
layers, resists, discharge layers for electron-beam lithography and SEM
(scanning electron microscope) inspection, and as coatings (especially
radiation-curable coatings), for electrostatic charge (ESC) and
electrostatic discharge (ESD) applications.
In electron-beam lithography using organic resists, which are insulators,
there can arise an accumulation of charge during the writing process due
to the absence of an adequate conducting path for immediate bleed-off of
the electrons. This charging can result in beam pattern displacement
deflection, loss of accuracy in pattern-to-pattern-overlay, or in extreme
cases a catastrophic discharge of voltage.
Traditionally, suggestions to circumvent this problem have included the use
of a discharge layer in the form of a conductor below or above the resist
coating. The layer could be in the form of thin evaporated or sputtered
metal coatings, indium-tin oxide films, or amorphous carbon films produced
by chemical vapor deposition processes. Although effective in some
contexts, these methods are not universally ideal since the processes
involved in their utilization tend to influence negatively the performance
of the resist, and in some cases are difficult to remove.
It is also useful to provide materials that can alleviate electrostatic
charging (that is, the unwanted accumulation of static electricity which
becomes capable of attracting unwanted airborne particles to e.g. cathode
ray tube screens and electronic component carriers), and alleviate
electrostatic discharge, in which static electricity is suddenly released
in a discharge that can distort the performance of electronic devices and
even damage or destroy electronic components. A material that can
facilitate the application and creation of such materials would be useful.
While polyaniline as described in the literature might be considered a
promising candidate to use to solve these needs, the practical use of
currently available polyaniline-based systems has been limited due to the
fact that solvents such as N-methyl pyrrolidinone are needed for the
application and removal. These solvents are known to interfere with some
substrate chemistries. In addition, they create interfacial problems and
can tend to dissolve certain substrates. Still other selective
polyaniline-derived systems are soluble in more benign organic solvents;
however, they are known to be difficult to remove once applied. It is also
useful to form a conducting resist which provides patterns of conductive
lines on a substrate. The steps involved in forming such lines can include
depositing a layer, exposing selected portions of the layer to a given
radiation (e.g., ultraviolet or visible light, electron beam, X-ray, or
ion beam) to create a solubility difference between exposed and unexposed
portions, and then removing the more soluble portions so that only the
desired pattern remains. This type of technique is often frustrated by the
difficulty of removing the unwanted material after it is developed.
The problem of charging in electron-beam methods arise because the resists
are insulators. With a conducting resist, which is one aspect of the
present invention, charging should not occur and a separate discharge
layer should not be needed.
Thus, there remains a need for a polymeric material which can be used in
the applications described herein, and which is easily applicable; is
chemically inert with respect to the systems with which it is used; is
environmentally benign, particularly in not requiring the use of organic
solvents which would volatilize into the atmosphere; and which is
removable when desired with minimal effort, with minimal harm to the
substrate itself.
DESCRIPTION OF PRIOR ART
The preparation of polyaniline systems is described in Li et al., "Soluble
Polyaniline" in Synthetic Metals, 20 (1987), at pages 141-149. That
article discloses that, even when the polymerization of the aniline is
carried out in the presence of the polyacid polystyrene sulfonic acid
(PSSA), the polymerization results in a precipitate from the aqueous
solution in which the aniline polymerization proceeds.
MacDiarmid et al., in "Polyaniline: A New Concept in Conducting Polymers",
Synthetic Metals, 18 (1987), at pages 285-290, describe polyaniline and
its protonated form, and indicate that the material is electrically
conductive.
U.S. Pat. No. 5,068,060 relates to the synthesis of poly(heterocyclic
vinylenes) as electrically conductive materials. According to the
disclosure, the backbone of the polymer is altered to impart desired
properties, and solubility is exhibited only in an undoped precursor form.
U.S. Pat. Nos. 4,929,389 and 4,880,508 relate to the synthesis of water
soluble conductive polymers, in which the moiety responsible for water
solubility is incorporated into the backbone of the polymer. By contrast,
in the present invention the final product exhibits both water solubility
and electrical conductivity, and does so without requiring alteration of
the polymer backbone.
U.S. Pat. No. 4,375,427 relates to the synthesis of thermoplastic-type
polymers that can be doped to be made conductive. However, the disclosed
materials are not water soluble, and are synthesized by condensation
reactions rather than oxidation reactions.
BRIEF SUMMARY OF THE INVENTION
One aspect of the present invention resides in a water-soluble electrically
conductive composition of matter comprising a polyacid and a polymer
comprising at least one conjugated region composed of repeating units
incorporating a conjugated basic atom. A preferred example of such a
repeating monomeric unit is aniline or a substituted aniline, which
incorporates a nitrogen atom in that the nitrogen can participate in the
conjugation in the polymer.
Another aspect of the present invention comprises solutions, in particular
aqueous solutions, of such compositions of matter.
Another aspect of the present invention comprises a process for forming a
water-soluble, electrically conductive composition of matter comprising a
polyacid and a polymer, such as polyaniline, comprising at least one
conjugated region composed of monomeric units incorporating a conjugated
basic atom. The process comprises forming a solution of said polyacid and
the corresponding monomer, wherein the number of acid groups in the
polyacid exceeds the number of protonatable basic atoms in the polymer to
be formed (it being understood that the polymer will include basic atoms
that are not protonatable), and polymerizing the monomer while controlling
the rate of initiation and the rate of propagation of said polymerization
such that the polymerization forms said water-soluble composition of
matter.
Further aspects of the invention includes compositions of matter which are
water-soluble and electrically conductive as described herein and which
are crosslinkable upon exposure to electromagnetic radiation to form
water-insoluble conductive products; structures having such a composition
of matter disposed thereon; processes of using such compositions of matter
to make electrically conductive layers and films; and the products formed
by such cross-linking, such as conducting resists.
Yet another aspect of the present invention is a structure, comprising a
substrate on which is disposed said water-soluble electrically conductive
composition of matter. Such structures include dielectric materials; said
composition of matter is useful as a conductive electron beam resist,
optical resist, X-ray resist, and electrostatic discharge layer.
A further aspect of the present invention comprises a method of disposing
said water-soluble, electrically conductive composition of matter on a
surface as e.g. a conductive resist or an electrostatic discharge layer.
DETAILED DESCRIPTION OF THE INVENTION
Without being bound by any particular theory of the present invention, the
observed behavior of the composition of matter which is one aspect of the
present invention is consistent with the belief that the polyacid and the
polymer which comprise the composition of matter are in mutual association
with each other. The association is believed to be more ionic in character
than covalent. Thus, while the composition of matter is described herein
as comprising polyacid and polymer, as described, it will be recognized
that in situ the composition of matter can also be understood as
comprising the polymer in which basic atoms, or even all basic atoms, are
protonated by hydrogen ions from the acidic groups of the polyacid.
However, it will be understood that the precise nature of the association
is not controlling.
Different regions of a given polyacid molecule may be associated with basic
atoms on distinct polymer molecules, without departing from the invention
whose noteworthy aspects include the water solubility and electrical
conductivity of the composition of matter.
The polyacid component of the present invention can, in its broadest
aspect, comprise any organic polymer at least some, or all, of whose
repeating units include an acidic moiety. The acidic moiety can be
carboxylic, i.e. --COOH, or can be another group such as a phosphonic acid
group, a phosphoric acid group, a boric acid group (i.e. --BO.sub.2 H), a
sulfuric acid group, or a sulfonic acid group. The acidic group can be
pendant directly from the polymer backbone, or can be a substituent on
another group which is itself pendant from the polymer backbone.
The preferred polyacids suitable for use in the present invention are
water-soluble at the concentrations described herein in which the
preparation of the complex of the present invention is carried out.
Preferred polyacids have polymer backbones which are vinylic, that is,
composed of repeating units of the generalized formula --(CH.sub.2 CHX)--,
wherein X is an acid group or is a substituent which is substituted with
an acid group.
Preferred examples of polyacids include poly(styrene sulfonic acid),
poly(acrylic acid), poly(methacrylic acid), poly(vinyl sulfonic acid),
poly(vinyl sulfuric acid), poly(vinyl boric acid), poly(styrene boric
acid), poly(vinyl phosphoric acid), and poly(styrene phosphoric acid). The
preferred polyacid is poly(styrene sulfonic acid), referred to at points
herein as PSSA.
It should also be recognized that polyacids suitable for the practice of
the present invention may comprise copolymers some repeating units of
which contain pendant acidic groups as described hereinabove and other
repeating units of which do not, provided that such copolymeric polyacids
exhibit the desired solubility in water. Such copolymers can be block
copolymers, or copolymers in which acidic and non-acidic monomeric units
are interspersed.
The polymer component of the compositions of matter of the present
invention comprises one or more conjugated regions composed of monomeric
units incorporating a conjugated basic atom. By "basic atom" is meant an
atom that can form the positive part of an ionic couple by electron
donation with the anionic moiety of the deprotonated acid group of the
polyacid. The preferred basic atom is nitrogen. Other basic atoms include
sulfur. The polymer is preferably of the type which can be prepared by
oxidation-type polymerization as distinguished from condensation
polymerization.
The polymer is characterized in that at least one region thereof is
conjugated as a whole and is composed of monomeric units each of which
incorporates a basic atom which is conjugated. Referring for simplicity to
the well-known means of depicting the structure of a molecule using
conventional atomic symbols and single and double bonds, by "conjugated"
is meant as to a region that the structure of the region can be depicted
in that means in more than one way (the actual structure in situ
representing an average of all such depictions), and as to an atom that
there is more than one way to depict the bonds connecting that atom to
adjacent atoms. It is preferred, though not necessary, to extend the
conjugation over the full extent of the polymer molecule. In the
conjugated system an electron is essentially delocalized over the entire
region of conjugated bonds. These electrons are more loosely bound and are
available for electrical conduction. It is only necessary to sufficiently
extend the conjugated region of an individual polymer molecule so that
when the conjugated region of an individual molecule is adjacent to a part
of the conjugated region of an adjacent molecule, and an electric field is
applied, an electron can flow along an individual molecule and hop from
one molecule to an adjacent molecule in a region where the conjugated
regions of the adjacent molecules overlap.
Examples of polymers incorporating the foregoing characteristics include
polymers containing conjugated regions, or composed entirely, of repeating
units which are substituted or unsubstituted aniline, thiophene, pyrrole,
and/or phenyl mercaptan (C.sub.6 H.sub.5 SH). Preferred examples of these
include polyaniline, polythiophene, polypyrrole, poly(p-phenylene
sulfide), and copolymers of these polymers. Polymers useful in the present
invention also include polymers of any of the corresponding monomers which
are ring-substituted with one or more straight or branched alkyl, alkoxy,
or alkoxyalkyl groups, which can contain from 1 up to about 30 carbon
atoms and preferably 1 to 6 carbon atoms, particularly where such
substituents are cross-linkable with each other as described in more
detail hereinbelow. It will also be recognized that polymers incorporated
within the compositions of matter of the present invention may also be
copolymers of any one or more of such monomers with other comonomers
having ethylenic unsaturation, including but not limited to ethylene,
propylene, vinyl chloride, styrene, vinyl alcohol, vinyl acetate. In such
cases, as described above, the conjugated region or regions containing the
basic monomeric units should comprise a block sufficiently long as to
render the composition of matter conductive.
The preferred polymers within the compositions of matter of the present
invention are polyaniline, poly{alkoxyalkyl aniline), poly(alkoxyaniline),
and poly(alkylaniline) wherein the alkoxy and alkyl groups contain 1 to 6
carbon atoms and more preferably about 2 carbon atoms.
The compositions of matter of the present invention are uniquely
characterized in that they exhibit solubility in water, and form in polar
solvents solutions that remain stable even over protracted periods of
time. These compositions of matter are also recoverable from such
solutions as solids, which are conductive and which can be redissolved
into water. In addition, the compositions of matter of the present
invention exhibit significant electrical conductivity in the solid state
as well as in solution in polar solvents.
The molecular weight of the compositions of matter of the present invention
can be virtually any that the practitioner may desire, depending on the
desired application. Thus, the compositions of matter may have a molecular
weight on the order of 1,000 to a molecular weight on the order of
100,000, but more preferably on the order of 10,000 to 25,000, e.g. about
20,000.
The preparation of the compositions of matter in accordance with the
present invention calls for polyacid, the desired monomer (or comonomers),
a suitable solvent, and an effective amount of an initiator for the
desired polymerization of the monomer(s).
The polyacid can be any polyacid meeting the characteristics described
above. The monomer is selected with regard to the desired final polymer;
in the preferred embodiment, the polyacid is PSSA and the monomer is
aniline. For applications intended to produce a cross-linked product, the
preferred monomers are o-ethylaniline or o-ethoxyaniline.
The solvent is a polar liquid in which the polyacid, monomer and final
complex are soluble. Water is the preferred solvent; the solvent may also
be an alkanol or a water/alkanol mixture.
The initiator is any material capable of initiating the oxidation
polymerization of the monomer(s) present. The preferred initiator is
ammonium persulfate, particularly when the monomer to be polymerized is an
aniline. Other useful initiators include hydrogen peroxide, AIBN, iron
trichloride, potassium permanganate, and others which will be readily
apparent to those of ordinary skill in this art.
The amounts of polyacid and monomer need to be selected such that the
number of acidic groups in the polyacid present in the reaction mixture
exceeds the numbers of the basic atoms present in the quantity of monomer
provided to the reaction mixture. Preferably, the final composition of
matter that is obtained will have an excess of acidic moieties not
associated with basic atoms in the polymer, thereby contributing to the
water solubility of the composition of matter. Thus, it will be understood
that as the ratio of acidic groups in the polyacid to basic atoms in the
monomer reaction mixture increases, the water solubility of the
composition of matter also increases. It is permissible that some of the
acidic moieties on the polyacid are converted to salts with a cation (such
as an alkali metal or ammonium), before or after the polymerization, so
long as sufficient acidic moieties are present that protonate the
protonatable basic atoms of the polymer so as to provide the desired
solubility and conductivity.
It has been discovered that if the polymerization of the monomer or
monomers in the presence of the polyacid is carried out under carefully
controlled conditions, the desired water-soluble, electrically conductive
composition of matter is formed and remains in solution until removal
thereof from solution is desired. The practitioner will readily be able to
confirm that the composition of matter of the present invention has been
formed because the product of the polymerization described herein is a
stable solution. By contrast, polymerizations that fail to produce the
desired water-soluble soluble composition of matter are readily
distinguished by the formation of a precipitate or an insoluble gel (which
is the result reported in the literature upon previous attempts at
polymerization of such monomers in the presence of acids such as PSSA).
In general, the careful control of the polymerization is characterized by
control of the rate of initiation of the polymerization, and of the rate
of propagation of the polymer. This control can be provided, in turn, by
controlling the temperature and adjusting the concentration of the
polyacid, the monomer, and the initiator to levels below those levels at
which the polymerization forms a precipitate. As indicated the
practitioner will readily be able to determine for any particular
combination of polyacid, monomer and initiator those concentrations
thereof at which the polymerization will lead to the desired formation of
the water-soluble, electrically conductive composition of matter in
accordance with the present invention. The examples which follow will
provide further guidance to the practitioner as to those concentration
conditions which permit formation of the desired water-soluble
electrically conductive composition of matter. The polymerization proceeds
effectively at room temperature (25.degree.-30.degree. C.). The
temperature should not exceed about 30.degree. C. because gelation can
occur due to overly rapid reaction. Thus, lower reaction temperatures are
preferred as they perm | | |
