U.S. patent application number 12/615901 was filed with the patent office on 2010-04-01 for functionalized main chain polymers.
Invention is credited to Thomas Haring.
Application Number | 20100081783 12/615901 |
Document ID | / |
Family ID | 34636816 |
Filed Date | 2010-04-01 |
United States Patent
Application |
20100081783 |
Kind Code |
A1 |
Haring; Thomas |
April 1, 2010 |
Functionalized Main Chain Polymers
Abstract
A non crosslinked, covalently crosslinked and/or ionically
crosslinked polymer, having repeating units of the general formula
(1) --K--R-- (1) In which K is a bond, oxygen, sulphur,
##STR00001## the radical R is a divalent radical of an aromatic or
heteroaromatic compound.
Inventors: |
Haring; Thomas; (Stuttgart,
DE) |
Correspondence
Address: |
FITCH EVEN TABIN & FLANNERY
120 SOUTH LASALLE STREET, SUITE 1600
CHICAGO
IL
60603-3406
US
|
Family ID: |
34636816 |
Appl. No.: |
12/615901 |
Filed: |
November 10, 2009 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11679020 |
Feb 26, 2007 |
7615599 |
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12615901 |
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10852594 |
May 24, 2004 |
7196151 |
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11679020 |
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PCT/DE2002/004414 |
Nov 22, 2002 |
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10852594 |
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Current U.S.
Class: |
528/226 ;
528/391 |
Current CPC
Class: |
C08J 5/18 20130101; B01D
71/68 20130101; B01D 67/0093 20130101; C08J 5/2218 20130101; H01M
8/1027 20130101; C08L 81/06 20130101; H01M 10/0565 20130101; H01M
8/1023 20130101; C08L 79/04 20130101; B01D 71/82 20130101; Y02P
70/50 20151101; B01D 69/141 20130101; C08L 71/10 20130101; H01M
8/1011 20130101; H01M 8/1081 20130101; H01M 10/052 20130101; H01M
8/1032 20130101; H01M 8/103 20130101; B01D 71/52 20130101; B01D
71/80 20130101; H01M 8/1025 20130101; C08G 65/48 20130101; B01D
2323/30 20130101; B01J 47/12 20130101; H01M 8/1048 20130101; Y02E
60/10 20130101; Y02E 60/50 20130101 |
Class at
Publication: |
528/226 ;
528/391 |
International
Class: |
C08G 75/23 20060101
C08G075/23; C08G 16/00 20060101 C08G016/00 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 22, 2001 |
DE |
101 58 006.1 |
Feb 28, 2002 |
DE |
102 08 679.6 |
Claims
1. A noncrosslinked, covalently crosslinked and/or ionically
crosslinked polymer, having repeating units of the general formula
(1) --K--R-- (1) in which K is a bond, oxygen, sulphur,
##STR00047## the radical R is a divalent radical of an aromatic or
heteroaromatic compound, wherein a) the radical R has at least in
part substituents of the general formula (2I), (2K), (4L), (4M),
(4N), (4O), (4P), (4Q), or (4R), ##STR00048## where the radicals
R.sup.1 independently of one another are a bond or a group having 1
to 40 carbon atoms, preferably a branched or unbranched alkyl or
cycloalkyl group or an optionally alkylated aryl group, M is
hydrogen, a metal cation, preferably Li.sup.+, Na.sup.+, K.sup.+,
Rb.sup.+, Cs.sup.+, TiO.sup.2+, ZrO.sup.2+ or an optionally
alkylated ammonium ion, and X is a halogen or an optionally
alkylated amino group, b) the radical R has at least in part
substituents of the general formula (5E) and/or (5F) ##STR00049##
in which R.sup.2, R.sup.3, R.sup.4 and R.sup.5 independently of one
another are hydrogen, a group having from 1 to 40 carbon atoms,
preferably a branched or unbranched alkyl or cycloalkyl group or an
optionally alkylated aryl group, it being possible for at least two
of the radicals R.sup.2, R.sup.3 and R.sup.4 to be closed to form
an optionally aromatic ring, and/or the radical R is at least in
part a group of the general formula (5C) and/or (5D) ##STR00050##
Description
[0001] Functionalised fluorine free main chain polymers, like
sulfonated poly aryl etherketones and polyethersulfones have been
developed by the company Dupont in the past as an alternative to
fluorinated cation exchanger like Nafion.RTM.. Such polymer
processed to membranes find use in membrane processes, particularly
in hydrogen fuel cells. One distinguishes at least two types of PEM
hydrogen fuel cells (PolymerElectrolyteMembrane hydrogen fuel
cells). The former convert hydrogen and the latter methanol. In
direct methanol fuel cells (DMFC) higher requirements are made to
the membranes, than in hydrogen fuel cells which are operated
exclusively with hydrogen at.
[0002] Ionically crosslinked membranes were developed by Kerres et
al. These are acid base polymer blends and polymer (blend)
membranes. An advantage of the ionically crosslinked acid base
blend membranes is the higher flexibility of the ionic bonds and
that these polymer/membranes don't dry so easily out at higher
temperatures and in consequence don't become brittle so fast
either. The ionic bindings show, however, the disadvantage that
they start at temperatures above 60 degrees Celsius to open
themselves what leads to a strong swelling up to the dissolving of
the membrane.
[0003] In earlier applications was suggested to enclose a
sulfonated engineering main chain polymer into a covalent network
of a second polymer. This procedure leads to technically applicable
membranes for the hydrogen hydrogen fuel cell, however, has the
disadvantage in the DMFC that during the operation the danger of
the bleeding out of the sulfonated component exists. So it was task
to develop a polymer, that bleeds out in aqueous or aqueous
alcoholic surroundings little or not at all. Ander "bleeding" you
shall anderstand that a water-soluble component is dissolved.
[0004] Furthermore the polymer shall show a mechanical stability as
good as possible and an improved swelling behavior. The swelling
behavior shall preferably increase at a temperature of 90.degree.
C. in deionised water around less than 90% as compared to the
control value at 30.degree. C. related to the extension in the
dimension (length, breadth, height).
[0005] A further object was to specify a crosslinked polymer which
can be used in fuel cells. The crosslinked polymer ought in
particular to be suitable for use in fuel cells upward of
80.degree. C., in particular upward of 100.degree. C. Membranes
produced from the polymer shall particularly be suitable in direct
methanol fuel cells.
[0006] Further disadvantage of the fluorine free polymeric cation
exchanger, like sulfonated poly aryl etherketones and sulfonated
polysulfones is their lower acid strength in comparison with a
polymeric fluorinated sulfonic acid, such as Nafion.RTM. of Dupont,
which is considered as a comparison standard from the experts. The
task was therefore provided to make available a polymer with a
higher acid strength than directly at the main chain sulfonated
polysulfone or directly at the main chain sulfonated
polyetheretherketone as PEEK or PEKEKK.
[0007] Furthermore it was task to provide a method for the
production of the crosslinked polymer, too, that permits to produce
the desired polymer in a simple way.
DESCRIPTION
[0008] These and additional not explicit mentioned objects are
achieved by means of a polymer according to the invention which is
not crosslinked, covalently crosslinked and/or ionically
crosslinked as described in the patent claim 1. Meaningful
variations of the polymer of the present invention and combinations
from this are described in the subclaims. Processes for preparing
the polymer of the present invention are described in the process
claims. The claims for the use of the polymer of the present
invention follow afterwards.
[0009] As far as the polymer according to the invention is a
polymer with a proton exchanging group, such as sulfonic acid,
phosphonic acid and/or carbonic acid, whose acid strength has been
increased according to the invention and the task, a covalent
and/or ionic crosslinking isn't mandatory.
[0010] The non crosslinked, covalently crosslinked and/or
optionally ionically crosslinked polymer according to the
invention, particularly covalently crosslinked and/or optionally
ionically crosslinked polymers, comprises repeating units of the
general formula (1)
-Q-R-- (1)
in which Q is a bond, oxygen, sulfur
##STR00002##
the radical R is a divalent radical of an aromatic or
heteroaromatic or aliphatic compound is.
[0011] Furthermore the invention concerns polymers with fluorine in
the main chain, such as polyvinylidendifluoride (PVDF),
poly(vinylfluoride) (PVF) and polychlorotrifluorethylene and
Analoga, like Kel-F.RTM. and Neoflon.RTM.. These polymers are
already known and are changed into polymers of the present
invention.
[0012] The polymers of the present invention get accessible by one
or several modification steps of the starting polymer of the
general formula (1). Polymers with repeating units of the general
formula (1) are already known. They include, for example,
polyarylenes, such as polyphenylene and polypyrene, aromatic
polyvinyl compounds, such as polystyrene and polyvinylpyridine,
polyphenylenevinylene, aromatic polyethers, such as polyphenylene
oxide, aromatic thioethers, such as polyphenylene sulfide,
polysulfones, such as Radel R.RTM. and Ultrason.RTM., and polyether
ketones, such as PEK, PEEK, PEKK and PEKEKK. Moreover, they also
embrace polypyrroles, polythiophenes, polyazoles, such as
polybenzimidazole, polyanilines, polyazulenes, polycarbazoles,
polyindophenines, polyvinylidendifluoride (PVDF) and
polychlorotrifluorethylene and analogues like Kel-F.RTM. and
Neoflon.RTM..
[0013] By one or more modifications with repeating units of the
general formular (1) a polymer according to the invention is
created with surprising properties.
[0014] By providing a polymer of the present invention, comprising
repeating units of the general formula (1) is made available which
is distinguished in that (a) the radical R has at least in part
substituents of the general formula (4J), (4K), (4L), (4M), (4N),
(4O), (4P), (4Q) and/or (4R),
##STR00003##
where the radicals R.sup.1 independently of one another show the
general formular (888-1) or (888-2)
##STR00004##
where M independently of one another is hydrogen, a one-or
multivalent cation, preferably Li.sup.+, Na.sup.+, K.sup.+,
Rb.sup.+, Cs.sup.+, TiO.sup.2+, ZrO.sup.2+, Ti.sup.4+, Zr.sup.4+,
Ca.sup.2+, Mg.sup.2+ or an optionally alkylated ammonium is and X
is a halogen or an optionally alkylated amino group, and and where
R.sup.2, R.sup.3, R.sup.4, R.sup.5 independently of one another is
hydrogen, (4A), (4B), (4C), (4D), (4E), (4F), (4G), (4H), (4I),
(4J), (4K), (4L), (4M), (4N), (4O), (4P), (4Q) and/or (4R) or a
group having from 1 to 40 carbon atoms, preferably a branched or
unbranched alkyl or cycloalkyl group or an optionally alkylated
aryl group or hetero aryl group is, which can be flourinated or
partly flourinated, it being possible for at least two of the
radicals R.sup.2, R.sup.3 and R.sup.4 to be closed to form an
optionally aromatic ring, and/or the radical R.sup.1 is a group of
the general formular (5A), (5B), (5C), (5D), (5E), (5F), (5G)
and/or (5H)
##STR00005## ##STR00006##
and b) the radical R has optionally bridges of the general formular
(6A), (6B), and or (6C),
##STR00007##
which join at least two radicals R to one another, Y being a group
having from 1 to 40 carbon atoms, preferably a branched or
unbranched alkyl or cycloalkyl group or an optionally alkylated
aryl group, Z is hydroxyl, a group of the general formula (7)
##STR00008##
or a group having a molecular weight of more than 14 g/mol composed
of the optional components (5A), (5B), (5C), (5D), (5E), (5F),
(5G), (5H), (4A), (4B), (4C), (4D), (4E), (4F), (4G), (4H), (4I),
(4J), (4K), (4L), (4M), (4N), (4O), (4P), (4Q), (4R), H, C, O, N,
S, P, halogen atoms, one or multivalent cation and m is an integer
greater than or equal to 2, it is possible in a manner which was
not immediately foreseeable to make available a polymer having
improved properties, in particular for membrane applications, an
improved swelling properties, a better proton conductivity and
further defined adjustable functional groups for the most different
technical applications.
[0015] At the same time the polymer of the invention and the
crosslinked polymer of the invention display a number of further
advantages.
[0016] These include, among others: [0017] The doped polymer
membranes have a low specific volume resistance, preferably less
than or equal to 100 Ohm.times.cm at 20.degree. C. [0018] The doped
polymer membranes possess only a low permeability for hydrogen,
oxygen and methanol. [0019] Also extremely thin membranes of the
polymer of the invention, with a total thickness of between 10 and
100 .mu.m possess sufficiently good material properties at
temperatures between 60.degree. C. and 82.degree. C. in particular
a very high mechanical stability and a low permeability for
hydrogen, oxygen and methanol. [0020] The doped polymer membrane is
suitable for use in fuel cells upward of 80.degree. C., in some
cases upward of 100.degree. C. and in particular cases upward of
110.degree. C. [0021] The doped polymer membrane is suitable for
use in fuel cells upward of 82.degree. C., in particular under
standard pressure. [0022] The doped polymer membrane can be
produced on an industrial scale.
[0023] In accordance with the present invention the polymer is
covalently and/or ionically crosslinked. In accordance with the
invention, crosslinked polymers are those polymers whose linear or
branched macromolecules, which are of the same or different
chemical identity and are present in the form of collectives, are
linked to one another to form three-dimensional polymer networks.
In this case the crosslinking may be effected both by way of the
formation of covalent bonds and by way of the formation of ionic
bonds.
[0024] The crosslinked polymer of the invention is preferably doped
with acid. In the context of the present invention, doped polymers
are those polymers which owing to the presence of doping agents
exhibit an increased proton conductivity in comparison with the
undoped polymers. Dopants for the polymers of the invention are
acids. Acids in this context embrace all known Lewis and Br.o
slashed.nsted acids, preferably inorganic Lewis and Bronsted acids.
Also possible is the use of polyacids, especially isopolyacids and
heteropolyacids, and mixtures of different acids. For the purposes
of the present invention, heteropolyacids are inorganic polyacids
having at least two different central atoms which are formed as
partial mixed anhydrides from in each case weak polybasic oxygen
acids of a metal (preferably Cr, Mo, V, W) and of a nonmetal
(preferably As, I, P, Se, Si, Te). They include, among others,
12-molybdatophosphoric acid and 12-tungstophosphoric acid.
[0025] Dopants which are particularly preferred in accordance with
the invention are sulfuric acid and phosphoric acid. One especially
preferred dopant is phosphoric acid (H.sub.3PO.sub.4).
[0026] Furthermore are particularly preferred the placement of
zirconium phosphate and titan sulfate by methods of someone skilled
in the art and furthermore preferred are modified and nonmodified
phyllosilicate or tectosilicate. With this modification method
Montmorillonite is particularly preferred, which is added during
the membrane forming process. Methods for the production of doped
plastic membranes are known.
[0027] The doping agents are fixed by a calcination process in the
membrane and transferred into the strong Lewis acidic form.
Particularly preferred is the calcination of titan sulfate and
zirconium phosphate in the membrane. Optionally the calcination is
followed by anew doping and/or further doping. Preferred doping
agents are again phosphoric acid, sulfuric acid and the above
mentioned hetero polyacids. The procedure can be repeated
optionally severalfold.
[0028] A suitable calcination temperature is the temperature range
of 60.degree. C. until just below the decomposition temperature of
the polymer to be doped. This is above 300.degree. C. for
flourinated polymers and polybenzimidazole. Particularly preferred
is the temperature range of 100.degree. C. to 300.degree. C.
[0029] Some doping agents are fixed in the membrane for a time
technically applicable by the calcination.
[0030] The crosslinked polymer of the invention has repeating units
of the general formula (1), especially repeating units
corresponding to the general formulae (1A), (1B), (1C), (1D), (1E),
(1F), (1G), (1H), (1I), (1T), (1K), (1L), (1M), (1N), (1O), (1P),
(1Q), (1R), (1S) and/or (1T):
##STR00009##
with 0<X, Y<100% based on the number of all repeating
units
##STR00010##
with 0<X, Y<100%
##STR00011##
[0031] Independently of one another here the radicals R.sup.6 which
are identical or different, are 1,2-phenylene, 1,3-phenylene,
1,4-phenylene, 4,4'-biphenyl, a divalent radical of a
heteroaromatic, a divalent radical of a C.sub.10 aromatic, a
divalent radical of a C.sub.14 aromatic and/or a divalent pyrene
radical. An example of a C.sub.10 aromatic is naphthalene; of a
C.sub.14 aromatic, phenanthrene. The substitution pattern of the
aromatic and/or heteroaromatic is arbitrary, in the case of
phenylene, for example, R.sup.6 may be ortho-, meta- and
para-phenylene.
[0032] The radicals R.sup.7, R.sup.8 and R.sup.9 designate
monovalent, tetravalent and trivalent aromatic or heteroaromatic
groups, respectively, and the radicals U, which are identical
within a repeating unit, are an oxygen atom, a sulfur atom or an
amino group which carries a hydrogen atom, a group having 1-20
carbon atoms, preferably a branched or unbranched alkyl or alkoxy
group, or an aryl group as a further radical.
[0033] The polymers with repeating units of the general formula (1)
that are particularly preferred in the context of the present
invention include homopolymers and copolymers, examples being
random copolymers, such as Victrex.RTM. 720 P and Astrel.RTM..
Especially preferred polymers are polyaryl ethers, polyaryl
thioethers, polysulfones, polyether ketones, polypyrroles,
polythiophenes, polyazoles, phenylenes, polyphenylenevinylenes,
polyanilines, polyazulenes, polycarbazoles, polypyrenes,
polyindophenines and polyvinylpyridines, especially polyaryl
ethers:
##STR00012## ##STR00013## ##STR00014## ##STR00015##
[0034] Especially preferred in accordance with the invention are
crosslinked polymers with repeating units of the general formula
(1A-1), (1B-1), (1C-1), (1I-1), (1G-1), (1E-1), (1H-1), (1I-1),
(1F-1), (1J-1), (1K-1), (1L-1), (1M-1) and/or (1N-1).
[0035] In the context of the present invention, n designates the
number of repeating units along one macromolecule chain of the
crosslinked polymer. This number of the repeating units of the
general formula (1) along one macromolecule chain of the
crosslinked polymer is preferably an integer greater than or equal
to 10, in particular greater than or equal to 100. The number of
repeating units of the general formula (1A), (1B), (1C), (1D),
(1E), (1F), (1G), (1H), (1I), (1J), (1K), (1L), (1M), (1N), (1O),
(1P), (1Q), (1R), (1S) and/or (1T) along one macromolecule chain of
the crosslinked polymer is preferably an integer greater than or
equal to 10, in particular greater than or equal to 100.
[0036] In one particularly preferred embodiment of the present
invention, the numerical average of the molecular weight of the
macromolecule chain is greater than 25,000 g/mol, appropriately
greater than 50,000 g/mol, in particular greater than 100,000
g/mol.
[0037] The crosslinked polymer of the invention may in principle
also contain different repeating units along a macromolecule chain.
Preferably, however, along one macromolecule chain it contains only
identical repeating units of the general formula (1A), (1B), (1C),
(1D), (1E), (1F), (1G), (1H), (1I), (1J), (1K), (1L), (1M), (1N),
(1O), (1P), (1Q), (1R), (1S) and/or (1T).
[0038] In the context of the present invention the radical R has at
least in part substituents of the general formula (4A), (4B), (4C),
(4D), (4E), (4F), (4G), (4H), (4I), (4J), (4K), (4L), (4M), (4N),
(4O), (4P), (4Q) and/or (4R), preferably of the general formula
(4A), (4B), (4C), (4D), (4J), (4K), (4L) and/or (4M), appropriately
of the general formula (4A), (4B), (4C), (4J), (4K) and/or (4L), in
particular of the general formula (4J) and/or (4K):
##STR00016## ##STR00017##
[0039] Here, the radicals R.sup.1 independently of one another
designate a bond or a group having from 1 to 40 carbon atoms,
preferably a branched or unbranched alkyl or cycloalkyl group or an
optionally alkylated aryl group, which optionally contain one or
more fluorine atoms.
[0040] In the context of one especially preferred embodiment of the
present invention, R1 is a methylene group (--CH.sub.2--) and/or a
partially or completely fluorinated methylene group (--CFH--) or
(--CF.sub.2--). Additionally to the structure as defined in the
previous sentence, R.sup.1 designates in a further especially
preferred embodiment a bond. R.sup.1 contains the formula (888-1)
or (888-2).
[0041] M stands for hydrogen, a one or multi-valent metal cation,
preferably Li.sup.+, Na.sup.+, K.sup.+, Rb.sup.+, Cs.sup.+,
Zr.sup.4+, Ti.sup.4+, ZrO.sup.2+, or an optionally alkylated
ammonium ion, appropriately for hydrogen or Li.sup.+, in particular
for hydrogen
[0042] X is a halogen or an optionally alkylated amino group.
[0043] Moreover, in accordance with the invention, the radical R
has in part substituents of the general formula (5A), (5C), (5D),
(5E), (5F), (5G), (5H) and/or (5B), preferably (5E),
##STR00018##
and/or the radical R is in part a group of the general formula (5G)
and/or (5H), preferably (5G).
##STR00019##
[0044] In this context the radicals R.sup.2, R.sup.3, R.sup.4 and
R.sup.5 independently of one another denote a group having from 1
to 40 carbon atoms, preferably a branched or unbranched alkyl or
cycloalkyl group or an optionally alkylated aryl group, it being
possible for at least two of the radicals R.sup.2, R.sup.3, R.sup.4
and R.sup.5 to be closed to form an optionally aromatic ring
[0045] Particularly advantageous effects can be achieved if R has
at least in part substituents of the general formula (5A-1) and/or
(5A-2).
##STR00020##
[0046] Here, the radicals R.sup.10 denotes an optionally alkylated
aryl group, which contains at least one optionally alkylated amino
group, or an optionally alkylated heteroaromatic, which either has
at least one optionally alkylated amino group or has at least one
nitrogen atom in the heteroaromatic nucleus. R.sup.11 is hydrogen,
an alkyl, cycloalkyl, aryl or heteroaryl group or a radical
R.sup.10 with the definition specified above, it being possible for
R.sup.10 and R.sup.11 to be identical or different.
[0047] Especially preferred in accordance with the invention are
substituents of the formula (5A-1) in which R.sup.10 is an
optionally alkylated aniline radical or pyridine radical,
preferably an alkylated aniline radical. Moreover, particular
preference is also given to substituents of the formula (5A-2) in
which R.sup.10 and R.sup.11 are optionally alkylated aniline
radicals or pyridine radicals, preferably alkylated aniline
radicals
[0048] In the context of the present invention the radical R can
have in part bridges of the general formula (6),
##STR00021##
which join at least two radicals R to one another, Y being a group
having 1 to 40 carbon atoms, preferably a branched or unbranched
alkyl or cycloalkyl group or optionally alkylated aryl group,
appropriately a linear or branched alkyl group containing from 1 to
6 carbon atoms Z designates hydroxyl, a group of the general
formula
##STR00022##
or a group having a molecular weight of more than 20 g/mol composed
of the optional components H, C, O, N, S, P and halogen atoms, and
m stands for an integer greater than or equal to 2, preferably
2.
[0049] The polymer of the invention is preferably doped with acid.
In the context of the present invention, doped polymers are those
polymers which owing to the presence of doping agents exhibit an
increased proton conductivity in comparison with the undoped
polymers. Dopants for the polymers of the invention are acids.
Acids in this context embrace all known Lewis and Br.o
slashed.nsted acids, preferably inorganic Lewis and Bronsted acids.
Also possible is the use of polyacids, especially isopolyacids and
heteropolyacids, and mixtures of different acids. For the purposes
of the present invention, heteropolyacids are inorganic polyacids
having at least two different central atoms which are formed as
partial mixed anhydrides from in each case weak polybasic oxygen
acids of a metal (preferably Cr, Mo, V, W) and of a nonmetal
(preferably As, I, P, Se, Si, Te). They include, among others,
12-molybdatophosphoric acid and 12-tungstophosphoric acid.
[0050] Dopants which are particularly preferred in accordance with
the invention are sulfuric acid and phosphoric acid. One especially
preferred dopant is phosphoric acid (H.sub.3PO.sub.4).
[0051] By way of the degree of doping it is possible to influence
the conductivity of the polymer membrane of the invention. As the
concentration of dopant goes up, the conductivity increases until a
maximum is reached. In accordance with the invention, the degree of
doping is reported as mole acid per mole repeating unit of the
polymer. In the context of the present invention a degree of doping
of between 3 and 15, in particular between 6 and 12, is
preferred
[0052] Processes for preparing doped polymer membrane are known. In
one preferred embodiment of the present invention they are obtained
by wetting a polymer of the invention for an appropriate time,
preferably 0.5-96 hours, with particular preference 1-72 hours, at
temperatures between room temperature and 100.degree. C. and, where
appropriate, under elevated pressure with concentrated acid,
preferably with highly concentrated phosphoric acid.
[0053] The spectrum of properties of the crosslinked polymer of the
invention can be modified by varying its ion exchange capacity. The
ion exchange capacity lies preferably between 0.5 meq/g and 1.9
meq/g, based in each case on the total mass of the polymer.
[0054] The polymer of the invention has a low specific volume
resistance, preferably of not more than 100 .OMEGA.cm,
appropriately of not more than 50 .OMEGA.cm, in particular of not
more than 20 .OMEGA.cm, in each case at 25.degree. C.
[0055] The properties of the polymer membrane of the invention may
be controlled in part by its total thickness. Nevertheless, even
extremely thin polymer membranes possess very good mechanical
properties and relatively low permeability for hydrogen, oxygen,
and methanol. They are therefore suitable for use in fuel cells
upward of 80.degree. C., appropriately upward of 100.degree. C.,
and in particular for use in fuel cells upward of 120.degree. C.,
without it being necessary to reinforce the edge region of the
membrane electrode assembly. The total thickness of the doped
polymer membrane of the invention is preferably between 50 and 100
.mu.m, appropriately between 10 and 90 .mu.m, in particular between
20 and 80 .mu.m.
[0056] In the context of one especially preferred embodiment of the
present invention it swells by less than 100% in deionized water at
a temperature of 90.degree. C.
[0057] Processes for preparing the crosslinked polymer of the
invention are obvious to the person skilled in the art.
Nevertheless, in the context of the present invention a procedure
which has proven especially suitable is that in which one or more
precursor polymers which individually or in toto contain the
functional groups a), b) and d), d) designating sulfinate groups of
the general formula (6)
##STR00023##
is or are reacted with a compound of the general formula (7)
YL.sub.m (7)
where L is a leaving group, preferably an F, Cl, Br, I, tosylate,
and n is an integer greater than or equal to 2, preferably 2. Each
precursor polymer preferably has repeating units of the general
formula (1). Furthermore, appropriately, it is not covalently
crosslinked. Where in at least one precursor polymer the radical R
has at least in part substituents of the general formula (5A) or is
at least in part a group of the general formula (5C), the reaction
with the compound (7) may also, moreover, lead to the formation of
bridges of the general formula (8) and/or (9).
##STR00024##
[0058] Also conceivable is the formation of bridges between
different substituents of the general formula (5A) and/or between
different groups of the general formula (5C).
[0059] In one particularly preferred embodiment of the present
invention a polymer mixture is used comprising
[0060] 1) at least one precursor polymer having functional groups
a),
[0061] 2) at least one precursor polymer having functional groups
b), and
[0062] 3) at least one precursor polymer having functional groups
d).
[0063] In another particularly preferred embodiment of the present
invention a polymer mixture is used comprising
[0064] 1) at least one precursor polymer having functional groups
a) and b) and
[0065] 2) at least one precursor polymer having functional groups
d)
[0066] In accordance with another particularly preferred embodiment
of the present invention it may also be particular advantageous to
use a polymer mixture comprising
[0067] 1) at least one precursor polymer having functional groups
a) and d) and
[0068] 2) at least one precursor polymer having functional groups
b).
[0069] Furthermore, processes wherein use is made of a polymer
mixture comprising
[0070] 1) at least one precursor polymer having functional groups
a) and
[0071] 2) at least one precursor polymer having functional groups
b) and d)
also constitutes a particularly preferred embodiment of the present
invention
[0072] In accordance with the invention it may also be
exceptionally appropriate to use at least one polymer having
functional groups of the general formula a), b) and d).
[0073] The precursor polymer or polymers for use in accordance with
the invention may in principle have different repeating units of
the general formula (1). Preferably, however, they have only
identical repeating units of the general formula (1A), (1B), (1C),
(1D), (1E), (1F), (1G), (1H), (1I), (1J), (1K), (1L), (1M), (1N),
(1O), (1P), (1Q), (1R), (1S) and/or (1T).
[0074] The number of repeating units of the general formula (1A),
(1B), (1C) (1D), (1E), (1F), (1G) (1H), (1I), (1J), (1K), (1L),
(1M), (1N), (1O), (1P), (1Q) (1R), (1S) and/or (1T) is preferably
an integer greater than or equal to 10, preferably at least 100
repeating units.
[0075] In one particularly preferred embodiment of the present
invention the numerical average of the molecular weight of the
precursor polymer or polymers is greater than 25,000 g/mol,
appropriately greater than 50,000 g/mol, in particular greater than
100,000 g/mol.
[0076] The synthesis of the precursor polymers having functional
groups of the general formula a), b) and/or d) is already known. It
can take place, for example, by reacting a polymer of the general
formula (1) with n-butyllithium in a dried aprotic solvent,
preferably tetrahydrofuran (THF), under an inert gas atmosphere,
preferably argon, and so lithiating it
[0077] In order to introduce the functional groups, the lithiated
polymer is [lacuna] in a manner known per se with suitable
functionalizing agents, preferably with alkylating agent of the
general formula
L-Subst. (10)
[0078] where Subst. is the substituent to be introduced; with
ketones and/or aldehydes, which are reacted to the corresponding
alkoxides; and/or with carboxylic esters and/or carbonyl halides,
which are reacted to the corresponding ketones. The introduction of
sulfonate groups may also be effected by reacting the lithiated
polymer with SO.sub.3, and the introduction of sulfinate groups by
reacting the lithiated polymer with SO.sub.2.
[0079] Through successive reaction with two or more different
functionalizing agents, polymers are obtained which have at least
two different substituents
[0080] For further details, refer to the state of the art, in
particular to the documents U.S. Pat. No. 4,833,219, J. Kerres, W.
Cui, S. Reichle; New sulfonated engineering polymers via the
melation route. 1. Sulfonated poly-(ethersulfone) PSU Udel.RTM. via
metalation-sulfination-oxidation" J. Polym. Sci.: Part A: Polym.
Chem. 34, 2421-2438 (1996), WO 00/09588 A1, whose disclosure
content is hereby explicitly incorporated by reference.
[0081] The degree of functionalization of the precursor polymers
lies preferably in the range from 0.1 to 3 groups per repeating
unit, preferably between 0.2 and 2.2 groups per repeating unit.
Particular preference is given to precursor polymers having from
0.2 to 0.8 groups a), preferably sulfonate groups, per repeating
unit. Moreover, precursor polymers having from 0.8 to 2.2 groups b)
per repeating unit have been found particularly appropriate.
Moreover, particularly advantageous results are achieved with
precursor polymers which have from 0.8 to 1.3 groups d) per
repeating unit.
[0082] In the context of the present invention it has proven
especially appropriate to dissolve the precursor polymer or
polymers in a dipolar-aprotic solvent, preferably in
N,N-dimethylformamide, N,N-dimethyl-acetamide, N-methylpyrrolidone,
dimethyl sulfoxide or sulfolane, and to react the solution with the
halogen compound, with stirring.
[0083] Particularly advantageous results can be achieved here
if
[0084] a) the polymer solution is spread as a film on a substrate,
preferably on a glass plate or a woven or nonwoven fabric, and
[0085] b) the solvent is evaporated, where appropriate at an
elevated temperature of more than 25.degree.
[0086] c) and/or under a reduced pressure of less than 1000 mbar,
to give a polymer membrane.
[0087] The properties of the polymer of the invention may also be
enhanced by
[0088] a) treating the polymer in a first step with an acid and
[0089] b) treating the polymer in a further step with deionized
water,
the polymer being treated where appropriate with an aqueous alkali
prior to the first step.
[0090] Possible fields of use for the polymer of the invention are
evident to the skilled worker. It is particularly suitable for all
applications which are indicated for crosslinked polymers having
low specific volume resistances, preferably less than 100 .OMEGA.cm
at 25.degree. C. On the basis of their characteristic properties,
they are suitable in particular for applications in electrochemical
cells, preferably in secondary batteries, electrolysis cells, and
in polymer electrolyte membrane fuel cells, especially in hydrogen
fuel cells and direct methanol fuel cells.
[0091] Moreover, they may also be employed to particular advantage
in membrane separation operations, preferably in the context of gas
separation, pervaporation, perstraction, reverse osmosis,
nanofiltration, electrodialysis, and diffusion dialysis.
[0092] The invention is illustrated in more detail below using
examples and comparative examples, without any intention that the
teaching of the invention should be restricted to these examples.
The property values reported, like the values described above, were
determined as follows:
[0093] In order to determine the ion exchange capacity, IEC, a
piece of protonated ionomer membrane was dried to constant weight.
1 mg of the membrane was introduced into about 50 ml of saturated
NaCl solution. As a result, there was ion exchange of the sulfonate
groups, with the H.sup.+ ions passing into the saturated solution.
The solution with the membrane was shaken or stirred for about 24
hours. Thereafter, 2 drops of the indicator bromothymol blue were
added to the solution, which was titrated with 0.1-normal NaOH
solution until the change of color from yellow to blue. The IEC was
calculated as follows:
IEC[meq/g]=(normality of NaOH[meq/ml]*consumption of
NaOH[ml]*factor of NaOH)/mass of membrane[g]
[0094] The specific volume resistance R.sup.sp of the membranes was
determined by means of impedance spectroscopy (IM6 impedance meter,
Zahner elektrik) in a Plexiglas unit with gold-coated copper
electrodes (electrode area 0.25 cm.sup.2). Here, in accordance with
the invention, the impedance at which the phase angle between
current strength and voltage was 0 designates the specific volume
resistance. The actual measurement conditions were as follows: 0.5
N HCl was used, the membrane under measurement was packed between
two Nafion 117 membranes, and the multilayer arrangement of Nafion
117/membrane/Nafion 117 membrane was pressed between the two
electrodes. In this way, the interfacial resistances between
membrane and electrode were eliminated by measuring first of all
the multilayer arrangement of all three membranes and then the two
Nafion 117 membranes alone. The impedance of the Nafion membranes
was substrated from the impedance of all three membranes. In the
context of the present invention the specific volume resistances
were determined at 25.degree. C.
[0095] In order to determine the swelling, the membranes were
equilibrated in deionised water at the respective temperature and
then weighed (=m.sup.swollen). The membranes were then dried at
elevated temperature in a drying oven and weighed again
(=m.sup.dry). The degree of swelling is calculated as follows:
Q=(m.sup.swollen-m.sup.dry)/m.sup.dry
a) polymers used
[0096] a-1) PSU Udel.RTM.
PSU P 1800 (Amoco)
[0097] a-2) PEK-S O.sub.3Li: Lithium salt of sulfonated polyether
ketone PEK
##STR00025##
Preparation:
[0098] 100 g of PEK-SO.sub.3H having an ion exchange capacity of
1.8 meq SO.sub.3H/g polymer were stirred for 24 hours in 1000 ml of
a 10% strength by weight aqueous LiOH solution. Thereafter the
Li-exchanged PEK- SO.sub.3Li was filtered off, washed with water
until the wash water gave a neutral reaction, and then dried at
100.degree. C. for 48 h. The resulting polymer contained 0.4
SO.sub.3Li units per repeating unit (ion exchange capacity (IEC) of
the protonated form=1.8 meq SO.sub.3H/g).
a-3) PSU-SO2Li:
[0099] Lithium salt of sulfinated polyether sulfone PSU
Udel.RTM.
##STR00026##
obtained in accordance with U.S. Pat. No. 4,833,219 or J. Kerres,
W. Cui, S. Reichle; New sulfonated engineering polymers via the
melation route. 1. Sulfonated poly(ethersulfone) PSU Udel.RTM. via
metalation-sulfination-oxidation" J. Polym. Sci.: Part A: Polym.
Chem. 34, 2421-2438 (1996) IEC of the protonated form=1.95 meq
SO.sub.2Li/g a-4) PSU-DPK:
##STR00027## [0100] obtained by reacting 2,2'-dipyridyl ketone with
lithiated PSU Udel (in accordance with WO 00/09588 A1); [0101] one
2,2'-dipryidyl ketone unit per repeating unit a-5) a-5) Synthesis
of PSU-P3-SO.sub.2Li, PSU-EBD-SO.sub.2Li, PSU-P3-SO.sub.2Li,
##STR00028##
[0102] First of all PSU Udel.RTM. was dissolved in dry THF and the
solution was cooled to -75.degree. C. under argon. Traces of water
in the reaction mixture were removed with 2.5 M n-butyllithium
(n-BuLi). The dissolved polymer was subsequently lithiated with 10
M n-BuLi. The batch was left to react for one hour and then
pyridine-3-aldehyde or 4, 4'-bis(N,N-diethylamino)benzo-phenone was
added. The reaction temperature was thereafter raised to
-20.degree. C. for one hour. For the reaction with SO.sub.2 it was
subsequently cooled again to -75.degree. C. and the SO.sub.2 was
passed in.
[0103] For working up, 10 ml of an isopropanol/water mixture was
introduced by syringe into the reaction solution, which was heated
to room temperature, and the polymer was precipitated in an excess
of isopropanol, and the resulting polymer was filtered off and
washed, where appropriate with isopropanol. For purification, the
polymer was suspended in methanol and filtered off again. The
polymer was dried in vacuo, preferably at 80.degree. C. The degrees
of substitution were obtained by quantitative evaluation of the
.sup.1H-NMR spectra.
TABLE-US-00001 TABLE 1 Synthsis of PSU-P3-SO.sub.2Li and
PSU-EBD-SO.sub.2Li Substitutionsgrad pro Ansatz
Wiederholungseinheit PSU-P3-SO.sub.2Li 10 ml 10 M BuLi 0.8
Pyridin-3-aldehyd 1000 ml THF 1.2 SO.sub.2Li 22.1 g PSU Udel .RTM.
5.35 g Pyridin-3-aldehyd SO.sub.2 PSU-DEB-SO.sub.2Li 10 ml 10 M
BuLi 0.4 4,4-Bis(N,N-diethyl 1000 ml THF amino)benzophenon 22.1 g
PSU Udel .RTM. 1.6 SO.sub.2Li 16.22 g 4,4'-Bis- (N,N-diethylamino)
benzophenon SO.sub.2
b.) Membrane Production
[0104] The polymers PEK-SO.sub.3Li, PSU-P3-SO.sub.2Li,
PSU-EBD-SO.sub.2Li, PSU-DPK and/or PSUSO.sub.2Li were dissolved in
NMP in accordance with Table 2 and filtered. The polymer solution
was then degassed in vacuo and subsequently admixed with
1,4-diiodobutane. It was subsequently poured onto a glass plate and
drawn but using a doctor blade. The glass plate was dried in an
oven at 60.degree. C. for 1 hour, then at 90.degree. C. for a
further hour and finally at 120.degree. C. under vacuum overnight.
The plate was cooled to room temperature and placed in a waterbath.
The membrane was separated from the glass plate and stored in 10%
HCl in an oven at 90.degree. C. for one day. It was subsequently
conditioned in deionized water at 60.degree. C.
[0105] The polymer of the present invention as described so far as
well as all possible combinations is characterised in that it has
at least one substituent of the general formula (4J), (4K), (4L),
(4M), (4N), (4O), (4P), (4Q) and/or (4R). If it has not a
substituent of the group mentioned above, than it sows at least a
substituent of the general formular (5C), (5D), (5G), (5H) or that
it is crosslinked by a crosslinking bridge of the general
formula(6B) and/or (6C).
[0106] Particularly preferred is the presence of substituent (2J)
and/or (2K).
[0107] Polymer-(2J)
[0108] Polymer-(2K)
[0109] Surprisingly, it has been shown that the acid strength of a
proton exchanging acid, especially of sulfonic acid and phosphoric
acid, is increased in the presence of a sulfo group at the carbon
atom bearing the proton exchanging group.
[0110] Subsequent figures illustrate the structures: [0111]
[0112] In the examples is R=polymer substituent
##STR00029## ##STR00030## ##STR00031## ##STR00032##
[0113] According to the present invention are also polymers which
start only from sulfinated polymers of the general formular (1) and
where the sulfinate groups are transformed in subsequent reactions
in sulfonic groups which are crosslinked partly or completely by a
carbon containing radical with a further sulfinated polymer. The
carbon containing radical R carries the functional groups. These
can be acids or/and bases.
##STR00033##
[0114] The polymers of the present invention and the membranes
produced from these are suited for the production of membrane
electrode arrays. The electrodes applied on the membrane, e.g. in
form of a paste, ink or by a powder coating method, can be
crosslinked covalently by alkylating crosslinker with reactive
groups to the membrane. The membrane as well as the applied
electrodes contain before the reaction not yet reacted sulfinic
acid groups, especially preferred are sulfinates. If di- or oligo
halogeno crosslinker, which if necessary contain functional groups
(4A) to (4R), are added to the electrode paste containing precursor
of polymeric cation exchanger as well as polymeric sulfinates, then
the polymeric sulfinates of the electrode paste react with the free
polymeric sulfinates of the membrane. The resulting covalent
crosslink solves an existing problem in the lacking bonding of the
electrodes to the membrane.
[0115] Possible fields of use for the polymer of the invention and
covalently crosslinked and/or ionically crosslinked polymer of the
invention are evident to the skilled worker. It is particularly
suitable for all applications which are indicated for crosslinked
polymers, especially with ion conductance. Particularly suitable
for applications in electrochemical cells, preferably in secondary
batteries, electrolysis cells, and in polymer electrolyte membrane
fuel cells, especially in hydrogen fuel cells and direct methanol
fuel cells.
[0116] Moreover, the polymers of the present invention may be
employed in other membrane separation operations, preferably in gas
separation, pervaporation, perstraction, reverse osmosis,
nanofiltration, electrodialysis, perstraction and diffusion
dialysis.
[0117] The invention is illustrated below using examples, without
any intention that the teaching of the invention should be
restricted to these examples.
[0118] The new polymers can be prepared by different methods.
[0119] As an example the route via a polymeric sulfinic acid is
shown. Polymeric sulfinic acids are accessible among others by
preparations described by Guiver et al. and also by Kerres et al.
The polymeric sulfinic acid salt reacts with a mono or oligo halide
bearing at least a further functional group (4A) to (4I) compound
by elimination of Li halide and sulfur alkylation or
sulfurarylation. The halide compound contains preferably the
halides flourine, chlorine, bromine and/or iodine as cleavable
anion. Iodine is eliminated already at room temperature (25.degree.
C.), bromine at temperatures over 30.degree. C. and chlorine is
eliminated only under dractic conditions. Flourine is a leaving
group if the flourine atom is connected to an aryl group or an
hetero aryl group, a simple example is p-flourine benzene
sulfonate.
[0120] The remaining radical e.g. (4A) to (4I) carries now the
desired functional group. By the neighboring sulfonic group the
acid strength is increased considerably. Between the sulfonic group
and the proton exchanging group, e.g. sulfonic acid, is at least
one carbon atom, preferred are the methylene group --CH2- and the
ethylene group --CH2-CH2-. The increase in acid strength is with up
to two carbon atoms in direct line to the proton exchanging group
clearly detectable. Membranes made from the polymer of the
invention show a better proton conductivity compared to identical
polymers with the proton exchanging group directly connected to the
aromatic ring. If one of the neighboring hydrogen atoms is
additionally replaced with flourine there is a further increase in
acid strength.
[0121] Subsequently is the preparation of a sulfonic acid high acid
strength is strongly increased by the neighboring group
--SO.sub.2--CH.sub.2--.
[0122] Sulfinated polysulfone PSU-SO.sub.2--Li is prepared as
described as under a-3). The IEC of the protonated form is 1.95 meq
SO.sub.2Li/g. It is dissolved in NMP and then an equivalent amount
of the sodium salt of bromine methane sulfonate is added. After
heating ne obtains the following compound dissolved in NMP
PSU-SO.sub.2--CH.sub.2--SO.sub.3.sup.-Na.sup.+ with an IEC of 1.95
meq SO.sub.3Li/g.
Instead of bromine methane sulfonate bromine ethane sulfonate
(sodium salt) is reacted in the next example with PSU-SO.sub.2--Li.
The reaction is successful and after evaporation of the solvent and
recrystalliation the pure compound
PSU-SO.sub.2--CH.sub.2CH.sub.2--SO.sub.3.sup.-Na.sup.+ is obtained.
If in the last example not the equivalent amount of bromine ethane
sulfonate (sodium salt) is added but only half,
PSU-SO.sub.2--CH.sub.2CH.sub.2--SO.sub.3.sup.-Na.sup.+ with an IEC
of 0.9 meq SO.sub.3Li/g is obtained and an IEC of 1.0 meq
SO.sub.2Li/g remains in the same molecule. The solvent is
evaporated in the drying oven at a temperature of appr. 80.degree.
C. until the solution has a concentration of appr. 10-15% weight.
Then it is cooled to room temperature (25.degree. C.) and an
equivalent amount of diiodine butane is added. The amount of
diiodine butane is calculated based on the crosslinking of the free
sulfinate groups. The solution is then processed to a membrane on a
glass plate and the remaining solvent NMP is evaporated in the
drying oven. A covalent crosslinked membrane is obtained which
proton exchanging group has a considerably bigger acid strength as
the control. Also the oxidation of the excess sulfinate groups to
sulfonic acid groups is economised as it should be done in the
control. The proton conductivity of the membrane with
PSU-SO.sub.2--CH.sub.2CH.sub.2--SO.sub.3H is 20% lower as in the
control, which has only PSU-SO.sub.3H as proton exchanging
group.
[0123] A considerable increase in the stability of the membrane has
been realised using PEEK-SO--Li with an IEC of 2.3 meq
SO.sub.2Li/g. Following figure explains the reaction:
##STR00034##
[0124] The membrane is transformed by posttreatment in acqueous
mineral acid and water in the acid form. Additionally the formed
salts are removed. The following figure explains one embodiment of
the polymer of the invention.
##STR00035##
R30 is (4A), (4B), (4C), (4F), (4G), (4H) and/or
##STR00036##
where H at the nitrogen can be substituted by an aryl- or alkyl
groupe. R.sup.1 can contain additionally a functional group from
(4A) to (4R), and a group from (5A) to (5H).
[0125] In a further especially preferred embodiment polymers are
prepared, which display one of the following groups:
##STR00037##
where P is a polymer as described on pages 9 to 16. R.sup.1 is
defined as in the description of R.sup.1 for the substituents (4A),
(4B), (4C), (4D), (4F), (4G), (4H), (4I), (4J), (4K), (4L), (4M),
(4N), (4O), (4P), (4Q) or (4R). R55 is one of the substituents from
(4A), (4B), (4C), (4D), (4F), (4G), (4H), (4I), (4J), (4K), (4L),
(4M), (4N), (4O), (4P), (4Q) or (4R).
[0126] Furthermore are preferred polymers which shows one of the
following groups
##STR00038##
where P is a polymer as described on pages 9 to 16. R.sup.1 is
defined as in the description of R.sup.1 for the substituents (4A),
(4B), (4C), (4D), (4F), (4G), (4H), (4I), (4J), (4K), (4L), (4M),
(4N), (4O), (4P), (4Q) or (4R). R55 is one of the substituents from
(4A), (4B), (4C), (4D), (4F), (4G), (4H), (4I), (4J), (4K), (4L),
(4M), (4N), (4O), (4P), (4Q) or (4R).
[0127] In the following further routes are disclosed to the person
skilled in the art to prepare at least one of the groups (15-1),
(15-2), (15-3), (15-4), (15-5) or (15-6).
[0128] After Guiver et. al. or Kerres et. al. and an application
not yet published polymeric sulfinic acids are state of the art. A
polymeric sulfinic acid is alkylated after the general formular
##STR00039##
[0129] To this e.g. sulfinated polysulfone is dissolved in NMP and
mixed with an equivalent amount of iodine etane carbonic acid.
Already after slight heating lithium iodide is eliminated and the
corresponding sulfone with an endstanding carboxyl group is
formed.
PSU-SO.sub.2Li+J-CH.sub.2--COOH.fwdarw.PSU-SO.sub.2--CH.sub.2--COOH+LiJ
Another example is sulfinated PEEK or PEK or PEKEKK or PEEKK.
PEEK-SO.sub.2Li+J-CH.sub.2--COOH.fwdarw.PEEK-SO.sub.2--CH.sub.2--COOH+Li-
J
[0130] A further route:
Polysulfone is metallated according to prior art with butyl lithium
at -60.degree. C. as described by e.g. Guiver. Then an equivalent
amount of methyl iodide is added. One let rise to -10.degree. C. in
order to completely methylate the polysulfone. The methylated
polysulfone is cooled down again to -60.degree. C. and the
equivalent amount of butyl lithium is added to the metallation.
Then the equivalent amount of one molecule SO.sub.2Cl.sub.2 per at
least more than once metallated methyl group is added and then
iodine dissolved in THF is injected. The preparation is described
in detail in the patent application DE 3636854 A1. The resulting
polymer is fluorinated by the generally known Finkelstein reaction
and is freed from solvent. The polymer is then hydrolised in water,
acid and/or base and the sulfonic acid is liberated.
PSU-Li+CH.sub.3J.fwdarw.PSU-CH.sub.3+LiJ
PSU-CH.sub.3 is e.g.
##STR00040## ##STR00041##
[0131] Further Route:
##STR00042##
[0132] Further Route:
##STR00043##
[0133] Further Route:
##STR00044##
[0134] The polymeric sulfinic acids (P-SO.sub.2Li) P=polymer can
react as a nucleophil with:
##STR00045##
in which R can be taken from R.sup.1.
Further Alkylating Agents are:
##STR00046##
[0135] R can independently from each other be taken from
R.sup.1.
* * * * *