This invention provides organosiloxane compounds containing silicon-bonded polyoxometalate (POM) structures that are present as pendant groups. The invention also provides methods for preparing these reaction products.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention relates to organosiloxane compounds containing ionically 
charged inorganic metal oxide complexes referred to as polyoxometalates. 
More particularly, this invention relates to organosiloxane compounds 
containing covalent bonds to the oxygen atoms of polyoxometalate (POM) 
structures. 
2. Background Information 
The chemical literature describes a class of ionically charged 
water-soluble oxides derived from polyvalent metals such as molybdenum, 
tungsten, and vanadium. Oxides of this type containing only the polyvalent 
metal and oxygen are referred to in the literature as "isopoly anions" or 
"isopoly complexes" and can be represented by the formula (M'.sub.m 
O.sub.y).sup.p. Anionic heteropoly complexes contain an additional 
metallic or non-metallic element such as hydrogen, phosphorus and silicon, 
and have been represented by the formula (X.sub.x M.sub.m O.sub.y).sup.q. 
In the foregoing formulae M' is a polyvalent metal, M is molybdenum, 
tungsten, vanadium niobium or tantalum, X represents the "hetero" atom, 
i.e. the additional non-metallic or metallic element, m, x and y are 
integers and p and q represent the charge on the complex, which can be 
calculated by adding the products obtained by multiplying the valences of 
X, M, and O by the value of the integer m, x or y associated with that 
atom. The values of p and q are negative except when M' is aluminum or 
gallium. The published literature reports that X can be any of at least 65 
metallic or non-metallic elements. 
A thorough discussion of polyoxometalates is contained in a text by M. T. 
Pope entitled "Heteropoly and Isopoly Oxometalates" published in 1983 by 
Springer Verlag. When the values of p and q in the foregoing formula are 
negative the oxometalate anions are associated with cations that are 
typically hydrogen, alkali metals, alkaline earth metals, NH.sub.4.sup.+ 
or R.sub.4 N.sup.+, where R represents a monovalent hydrocarbon radical. 
The type of anion will affect the chemical and physical properties of the 
polyoxometalate, including solubility, and the properties of reaction 
products of the POM. 
While there are a very large number of known polyoxometalates, 
investigators have found that most of these can be characterized by 
relatively few structures. These structures consist of groups of MO.sub.6 
octahedra and XO.sub.4 tetrahedra that share edges, corners, and, 
occasionally, faces with adjacent polyhedra. 
The structure of a particular polyoxometalate, the heteropolyacid H.sub.3 
PW.sub.12 O.sub.40 .multidot.6H.sub.2 O, was described by J. F. Keggin, 
Nature, 1933, 131, p. 908 as a cluster of edge-shared polyhedra, and his 
name has been given to the polyhedron type of POM structure. 
The structures of a number of POM's is discussed in the aforementioned text 
by Pope, in a text by M. Pope and A. Muller in Angew. Chem., ( 
International English Edition), 30 (1991) 34-48, by G. Tsigdinos in an 
article entitled "Heteropoly Compounds of Molybdenum and Tungsten" that is 
part of a collection entitled Topics In Current Chemistry, 1978, 76, P. 1, 
and by V. Day and W. Klemperer in Science, 1985, 228, P. 553. 
Of particular interest are POM's containing vanadium, molybdenum, tungsten, 
niobium and tantalum in combination with hydrogen, phosphorus or silicon 
as the heteroatom. 
It has been reported that the chemical and physical properties of POM's can 
be varied over a wide range by choice of the appropriate polyvalent metal 
and heteroatoms. 
Keggin structure anions of the formula (XM.sub.12 O.sub.40).sup.n- where M 
is molybdenum or tungsten, X is Si.sup.4+, P.sup.5+, B.sup.3+, Ge.sup.4+, 
Co.sup.2+ or Co.sup.3+ have been defined in the literature. When X is 
silicon and M is tungsten or molybdenum, n is 4. 
Under mildly basic conditions, one or more of the MO groups from a POM 
anion can be removed to form a deficient or "lacunary" structure. The 
structure resulting from removal of one MO group can be represented by the 
formula XM.sub.11 O.sub.39.sup.p-. The vacancy left by the departing group 
can be filled with other atoms or groups. 
Another common structure of polyoxometalates is referred to as a Dawson 
structure and is represented by the formula X.sub.2 M.sub.18 
O.sub.62.sup.p-. The heteroatom represented by X in this structure is 
phosphorus or arsenic, and the structure conceptually resembles a dimer of 
a deficient or "lacunary" Keggin structure in which three of the twelve M 
atoms have been removed. When the oxygen atoms are omitted the 
transformation to a Dawson type structure can be represented as 
EQU XM.sub.12 -3M.fwdarw.XM.sub.9 .times.2=X.sub.2 M.sub.18. 
Reactions of the lacunary POM W.sub.11 SiO.sub.39.sup.8- with 
monohydrocarbyltrichlorosilanes, RSiCl.sub.3, have been reported by W. 
Knoth [J. Am. Chem. Soc., 101: 3, 759-760 (1979) . When the reaction is 
carried out in an unbuffered aqueous solution, the WO.sup.4+ unit required 
for a complete or "non-lacunary" structure is replaced with an (RSi).sub.2 
O.sup.4+ group in which each of the two silicon atoms is bonded to two 
oxygen atoms of the POM and the product corresponds to the formula 
(RSi).sub.2 W.sub.11 SiO.sub.40.sup.4+. 
The reaction of monohydrocarbylsilanes RSiX.sub.3 with the potassium and 
ammonium derivatives of the same lacunary POM used by Knoth is described 
by P. Judeinstein et al. [J. Chem. Soc., Dalton Trans. (1991) 1991-1997]. 
In the formula for the silane R is ethyl, vinyl, decyl or phenyl and X is 
chlorine or alkoxy. In one of the examples, K.sub.4 SiW.sub.11 O.sub.39 
and vinyltriethoxysilane are reacted in an aqueous solution and the 
product isolated as the tetrabutylammonium salt of the formula [Bu.sub.4 
N].sub.4 SiW.sub.11 O.sub.39 O(SiCH.dbd.CH.sub.2).sub.2. 
The incorporation of POM structures into organic polymers by reacting the 
vinyltrichlorosilane/POM reaction product described in the immediately 
preceding paragraph or the corresponding allyl- or 3-methacryloxypropyl 
trichlorosilane/POM reaction product with styrene or methyl methacrylate 
using a free radical polymerization is described by P. Judeinstein in 
Chemistry of Materials, 4, 4-7 (1992). 
The reaction of the trivacant lacunary anion SiW.sub.9 O.sub.34.sup.10- 
with R'SiCl.sub.3 where R' is hydrogen, ethyl, n-butyl, vinyl, phenyl or 
p-tolyl is reported by N. Ammari [New. J. Chem, 15, 607-608 (1991)]. 
The present inventors are not aware of any attempts by others to 
incorporate POM structures into organosiloxane oligomers and polymers. The 
difference in physical, electrical, and other properties between cured 
polyorganosiloxanes and POM's should provide unique property combinations 
if it were possible to incorporate POM structures into polyorganosiloxane 
molecules. 
One objective of this invention is to incorporate polyoxometalate (POM) 
structures into organosiloxane polymers and oligomers by means of covalent 
bonding. 
SUMMARY OF THE INVENTION 
The objectives of the present invention can be achieved by reacting 
polyorganosiloxanes containing silicon-bonded reactive groups with 1) 
POM's having lacunary structures, or 2) reaction products of POM's with 
silanes containing an alkenyl radical or silicon bonded hydrogen atom and 
at least two hydrolyzable groups. The POM structures are present as 
pendant groups in the final polyorganosiloxane molecules. 
DETAILED DESCRIPTION OF THE INVENTION 
One embodiment of this invention provides organosiloxane compounds in the 
form of oligomers and polymers comprising terminal units of a formula 
selected from the group consisting of Y.sub.a R.sup.1.sub.3-a SiO.sub.0.5 
and 
##STR1## 
a first repeating unit of the general formula --[Si(R.sup.1).sub.2 O]-- 
and a second repeating unit of a formula selected from the group 
consisting of 
##STR2## 
where O.sub.1, O.sub.2, O.sub.3 and O.sub.4 are part of one 
polyoxometalate anion exhibiting a valence of x- and a general formula 
selected from the group cons i sting of XM.sub.11 O.sub.39.sup.x-, 
X'M.sub.9 O.sub.34.sup.x- and X".sub.2 W.sub.17 O.sub.61.sup.x.sup.-, M is 
tungsten or molybdenum, W is tungsten, X is selected from the group 
consisting of Si.sup.+4, B.sup.+3 , Ge.sup.+4, P.sup.+5, Fe.sup.+3 and 
As.sup.+5, X' is selected from the group consisting of Si.sup.+4, P.sup.+5 
and Ge.sup.+4, X" is selected from the group consisting of P.sup.+5 and 
As.sup.+5 any cation associated with said polyoxometalate anion is 
selected from the group consisting of hydrogen alkali metals and 
R.sup.5.sub.4 N.sup.+, where each R.sup.5 represents a monovalent 
hydrocarbon radical, each R.sup.1 and R.sup.4 are individually selected 
from the group consisting of unsubstituted and substituted monovalent 
hydrocarbon radicals, each R.sup.2 is individually selected from the group 
consisting of hydrogen and monovalent hydrocarbon radicals, R.sup.3 
represents a single bond or an alkylene radical, Y represents a halogen 
atom or a hydrolyzable group, a is 2 or 3 and p is at least 2. 
The hydrolyzable groups represented by Y include any that will not 
interfere with reaction of the polyorganosiloxane with the 
polyoxometalate. Suitable groups include but are not limited to alkoxy, 
ketoximo, carboxyl and aminoxy. The halogen atom represented by Y is 
preferably chlorine. 
The POM structures that characterize the present reaction products are 
anionic and carry a negative charge represented by x- in the preceding 
formulae. These anions are associated with an cation that is typically 
hydrogen, an alkali metal, alkaline earth metal or R.sup.5.sub.4 N.sup.+, 
where each R.sup.5 represents a monovalent hydrocarbon radical that may or 
may not be identical to the other three R.sup.5 radicals. The R.sup.5 
radicals are preferably identical and are preferably alkyl containing from 
1 to 10 or more carbon atoms. 
The type of cation will determine the physical and chemical properties of 
the present reaction products. 
This invention also provides methods for preparing organosiloxane compounds 
containing covalently bonded anionic polyoxometalate groups. 
Organosiloxane compounds containing repeating units corresponding to 
formula I, II and III can be prepared by reacting 1) at least one 
polyorganosiloxane wherein each of the terminal silicon atoms contains two 
or three hydrolyzable groups with 2) a lacunary form of a polyoxometalate 
anion using a molar ratio of polyoxometalate to polyorganosiloxane of at 
least 1:1. This ratio is preferably from 2:1 up to about 5:1. 
Organosiloxane compounds containing repeating units represented by formulae 
IV and V can be prepared by a hydrosilation reaction using an 
organosiloxane oligomer or polymer containing at least one silicon-bonded 
hydrogen atom with the reaction product of 1) a lacunary form of a 
polyoxometalate and 2) a silane of the general formula CR.sup.2.sub.2 
.dbd.C(R.sup.2)R.sup.3 SiR.sup.4.sub.n Z.sub.3-n, where n is 0 or 1, each 
R.sup.2 is individually selected from the hydrogen atom and unsubstituted 
and substituted monovalent hydrocarbon radicals, R.sup.3 represents a 
single bond or an alkylene radical, R.sup.4 represents a monovalent 
hydrocarbon radical selected from the same group as R.sup.1 but excluding 
alkenyl radicals, and Z represents a hydrolyzable group. Alternatively, 
the silicon-bonded hydrogen atom can be present on the POM/silane reaction 
product and the ethylenically unsaturated hydrocarbon radical represented 
by -R.sup.3 C(R.sup.2)C.dbd.C(R.sup.2.sub.2) can be present on the 
organosiloxane polymer or oligomer. 
The POM/organosiloxane reaction products are prepared using hydrosilation 
reaction and characterized by the presence of the POM-containing units as 
pendant groups that are bonded through an alkylene radical to a silicon 
atom of the organosiloxane molecule used as the reactant. Because two 
silane molecules are bonded by one POM structure and each silane contains 
an alkenyl radical, the POM-containing units typically link two 
polyorganosiloxane molecules together. 
The Polyoxometalate Reactant 
The anionic portion of polyoxometalates (POM's) used to prepare the 
polymers of this invention exhibit deficient or "lacunary" structures that 
can be represented by one of the Keggin structures (1) XM.sub.11 
O.sub.39.sup.y- and (2) X'M.sub.9 O.sub.34.sup.y-, or by the monolacunary 
Dawson structure (3) X".sub.2 W.sub.17 O.sub.61.sup.y-. In these 
structures M is tungsten or molybdenum, W is tungsten, X is selected from 
the group consisting of Si.sup.+4, B.sup.+3, Ge.sup.+4, p.sup.+5, 
Ga.sup.+3, Fe.sup.+3 and As.sup.+5, X' is selected from the group 
consisting Si.sup.+4, P.sup.+5 and Ge.sup.+4, X" is selected from the 
group consisting of P.sup.+5 and As.sup.+5, and y- represents the value of 
the anionic charge on the anion. 
In the Keggin structures, M is tungsten or molybdenum. When X represents 
silicon, the numerical value of x- in structure 1 is equal to the sum of 
the valences of silicon (+4), 11 times the valence of M (11.times.6) and 
39 times the valence of oxygen [39.times.(-2)], which calculates to -8. 
When the lacunary POM structure is reacted with an oligomeric or polymeric 
organosiloxane, four oxygen atoms of the lacunary structure react with two 
silicon atoms, and the valence of the POM anion decreases to -4. 
When the element represented by X is silicon, pentavalent phosphorus or 
tetravalent germanium, which represent preferred embodiments, the 
polyoxometalate can exist in the "trilacunary" form represented by formula 
2. 
The POM's are present in combination with associated cations that are 
typically alkali or alkaline earth metals or ammonium groups of the 
formula R.sub.5 N.sup.+ or H.sub.4 N.sup.+, where R.sup.5 represents a 
monovalent hydrocarbon radical. R.sup.5 is preferably alkyl containing 
from 1 to 20 or more carbon atoms, and is most preferably butyl, hexyl, 
heptyl or dodecyl. 
Methods for preparing the POM's used as reactants for preparing the 
organosiloxane compounds of this invention are reported in the chemical 
literature. Specific references include G. Herve et al., Inorganic 
Chemistry, 1977, 16, 2115 for synthesis of SiW.sub.9 O.sub.34.sup.10- and 
the corresponding germanium compound as the sodium salts and A. Teze et 
al., Journal of Inorganic and Nuclear Chemistry, 1977, 39, 999 for the 
synthesis of the potassium salt of SiW.sub.11 O.sub.39.sup.8-. A number of 
methods for preparing POM's are described in volume 27 of a text entitled 
"Inorganic Syntheses", beginning on page 71 (John Wiley and Sons, New 
York). 
Detailed procedures for preparing specific POM's are described by King, 
Hazen and Hill in Inorganic Chemistry, 1992, 31, 5316. 
Non-lacunary or complete Keggin structures of POM's with anions 
corresponding to the formula YM.sub.12 O.sub.40 can be prepared by adding 
an acid to an aqueous solution of sodium tungstate or sodium molybdate in 
the presence of a solubilized compound, such as an alkali metal silicate, 
containing the heteroatom represented by Y in the general formula for the 
POM. 
In accordance with one embodiment of the present method, a organosiloxane 
polymer or oligomer containing two or three hydrolyzable groups at each 
terminal position is reacted with at least one POM having a lacunary 
structure. The lacunary structures can be generated during preparation of 
the POM by using the appropriate ratio of molybdate or tungstate salt to 
heteroatom compound corresponding to the formula of the desired structure 
and maintaining the pH of the reaction mixture at no higher than 4.8. 
Alternatively, a complete POM structure can be converted to a lacunary 
structure by hydrolysis under basic conditions. 
POM's containing hydrogen, sodium or potassium as the cation are at least 
moderately soluble in water. The order of solubilities are H&gt;Na&gt;K. If the 
cation is tetraalkylammonium and the alkyl radicals contain from 1 to 
about 4 atoms the compounds are insoluble in water but soluble in polar 
organic solvents. When the alkyl radicals bonded to nitrogen contain more 
that about 4 carbon atoms the compounds are also soluble in non-polar 
organic solvents such as liquid hydrocarbons. 
POM's suitable for reaction with silanes or organosiloxane compounds in 
accordance with the present method can be prepared from aqueous solutions 
of the corresponding alkali metal POM salt by adding an excess of a 
water-soluble tetraalkylammonium compound, which causes the corresponding 
ammonium salt of the POM to precipitate. Conversion of an alkali metal POM 
salt to a tetraalkylammonium salt that is soluble in non-polar organic 
solvents can be achieved using a phase transfer reaction with a 
tetraalkylammonium halide dissolved in the organic solvent. In this 
instance the nitrogen-bonded alkyl radicals should contain more than about 
4 carbon atoms. The preparation of POM's using phase transfer reactions is 
described by Katsoulis and Pope (J. American Chem. Soc., 1984, 106, 2737); 
and Corigliano and DiPasquale (Inorganica Chimica Acta, 1975, 12, 99). 
Specific reactants and conditions for preparing POM anions with a variety 
of associated cations are described in sufficient detail in the literature 
that a complete discussion of the subject is not required in this 
specification. The preparation of preferred POM's is described in the 
accompanying examples. 
The Organosiloxane Reactant 
The organosiloxane reactant used to prepare copolymers containing repeating 
units corresponding to the foregoing formulae I, II, and III is an 
organosiloxane polymer or oligomer with terminal units of the formula 
Y.sub.a R.sup.1.sub.3-a SiO.sub.0.5 and repeating units of the formula 
Si(R.sup.1).sub.2 O and, optionally, Y.sub.2 SiO. In these formula the 
R.sup.1 substituents represent unsubstituted or substituted monovalent 
hydrocarbon radicals, Y is a hydrolyzable group and a is 2 or 3. When more 
than one hydrocarbon radical represented by R.sup.1 is bonded to a silicon 
atom, these hydrocarbon radicals can be identical or different. This 
reactant is also referred to in this specification as a 
"polyorganosiloxane". 
Repeating units containing two hydrolyzable groups represented by Y can be 
formed during preparation of the polyorganosiloxane by hydrolysis of one 
of the Y groups on a terminal unit and subsequent condensation with the 
terminal unit of another polyorganosiloxane molecule to form a siloxane 
bond. 
Suitable hydrolyzable groups that can be represented by Y include but are 
not limited to halogen, particularly chlorine and bromine, alkoxy, 
carboxy, amidoxy, and ketoximo. Halogen atoms and alkoxy groups containing 
from 1 to 4 carbon atoms are preferred based on cost and the nature of the 
by-products generated during reaction with the POM. 
The polyorganosiloxane can contain as few as two up to one hundred or more 
siloxane units, and can have a linear or branched structure. Branched 
structures contain at least one trifunctional siloxane unit of the formula 
R.sup.1 SiO.sub.3/2 and/or tetrafunctional unit of the formula SiO.sub.4/2 
in additional to the difunctional units. The polyorganosiloxane preferably 
contains from 10 to about 100 repeating units. 
Examples of suitable hydrocarbon radicals that can be represented by 
R.sup.1 include but are not limited to alkyl such as methyl, ethyl and 
n-propyl, substituted alkyl such as chloromethyl and perfluoroalkylethyl 
such as 3,3,3-trifluoropropyl, alkenyl such as vinyl and allyl, cycloalkyl 
such as cyclohexyl, aryl such as phenyl, alkaryl such as tolyl and xylyl 
and aralkyl such as benzyl. R.sup.1 is preferably alkyl containing from 1 
to 4 carbon atoms, 3,3,3-trifluoropropyl or phenyl. Most preferably at 
least one of the R.sup.1 substituents on each silicon atom is methyl. 
Methods for preparing organosiloxane polymers and oligomers containing 
three hydrolyzable groups at the terminal positions are described in the 
prior art. 
A preferred method for preparing trichlorosilyl-terminated organosiloxane 
oligomers and polymers is described in U.S. Pat. No. 3,161,614, issued to 
P. Brown and J. Hyde. This method comprises reacting a silanol terminated 
organosiloxane containing from 2 to about 100 siloxane units with a 
stoichiometric excess of silicon tetrachloride in the presence of a 
suitable acid acceptor such as an amine. The reaction is typically 
exothermic, and the reactants may require cooling to avoid an 
uncontrolled, potentially hazardous reaction. 
The average structural formula for preferred trichlorosilyl-terminated 
polyorganosiloxanes can be written as 
##STR3## 
In this formula R.sup.1 is a monovalent hydrocarbon radical as defined in a 
preceding section of this specification and z represents the degree 
polymerization of the silanol-terminated organosiloxane compound used to 
prepare the chlorinated polyorganosiloxane. Data from .sup.29 Si nuclear 
magnetic resonance collected by the present inventor indicate the average 
value of q to typically be between 0 and 1. 
Trialkoxysilyl-terminated polyorganosiloxanes can be prepared by reacting a 
silanol-terminated organosiloxane with an alkyl orthosilicate. No acid 
acceptor is needed, however a catalyst such as sodium acetate can be added 
to the reaction mixture. Reaction temperatures of from 50.degree. to about 
200.degree. C. may be required to obtain a useful yield of product in a 
reasonable time period. 
The average formula for preferred trialkoxysilyl-terminated 
polyorganosiloxanes is similar to that of the trichlorosilyl species 
described in a preceding section of this specification, with the exception 
that the chlorine atoms are replaced by alkoxy groups. 
Reaction of the POM with the Polyorganosiloxane 
Organosiloxane compounds containing repeating units corresponding the 
formulae I, II and II in the preceding sections of this specification are 
prepared by reacting a polyorganosiloxane, which includes organosiloxane 
oligomers, containing two or three hydrolyzable groups at each terminal 
position with a lacunary POM. The cation associated with the POM is 
typically hydrogen, an alkali metal or tetraalkylammonium. For convenience 
organosiloxane polymers and oligomers will both be referred to hereinafter 
as polyorganosiloxanes. 
The reaction between the POM and the polyorganosiloxane can be conducted by 
dissolving both reactants in a suitable solvent or a mixture of solvents 
under ambient conditions. The mixture can be heated up to the reflux 
temperature of the solvent to accelerate solubilization of the reactants. 
Because polyorganosiloxanes are typically not soluble in solvents 
containing water, the POM is preferably in the form of an ammonium salt or 
other salt that is at least partially soluble in the reaction medium. 
Alternatively, the polyorganosiloxane is dissolved in a suitable organic 
solvent, following which an alkali metal salt of the POM is added as a 
solid and the resultant slurry is stirred for a sufficient time to react 
the slightly POM with the polyorganosiloxane to form a product that is 
soluble in the reaction medium. The reaction mixture is then filtered to 
remove undissolved solids that are typically unreacted POM and an 
inorganic salt of the alkali metal that was initially associated with the 
POM. 
If it is desired to precipitate the POM/polyorganosiloxane reaction product 
from a non-polar solvent or a mixture of polar and non-polar organic 
solvents, such as a mixture of toluene and acetonitrile, a lower alkyl 
ammonium salt such as tetra-n-butyl ammonium chloride is added to the 
reaction mixture. 
Depending upon the nature of the POM cation, the organic liquid used for 
the reaction medium can be polar, non-polar or a mixture of polar and 
non-polar liquids, and the concentration of POM is from 1 to 50 weight 
percent, based on the total weight of the reaction mixture. 
Organosiloxane compounds containing repeating units corresponding to the 
formulae 
##STR4## 
are prepared by first reacting the lacunary POM with at least two moles 
per mole of POM of a silane containing 1) an alkenyl radical or a 
silicon-bonded hydrogen atom and 2) two or three silicon-bonded 
hydrolyzable groups. Any remaining valences on the silicon atom are 
satisfied by monovalent hydrocarbon radicals represented by R.sup.4. 
Reaction products of POM's and vinyltrichlorosilane and a method for 
preparing these reaction products are described by P. Judeinstein et al. 
in J. Chem. Soc. Dalton Trans. 1991, pp. 1991-1997. Alternatively, the 
locations of the alkenyl radical and silicon-bonded hydrogen atom can be 
reversed. 
Reactions between silicon-bonded hydrogen atoms and alkenyl radicals are 
referred to as hydrosilation reactions, and are catalyzed by metals from 
the platinum group of the periodic table and compounds of these metals. 
Depending upon whether the hydrocarbon radical represented by R.sup.4 is 
present or absent in the silane that is reacted with the polyoxometalate 
(POM) the reaction product of the POM and a silane containing a 
silicon-bonded alkenyl radical can be represented by the formula 
##STR5## 
where each R.sup.2 individually represents a hydrogen atom or a monovalent 
hydrocarbon radical, R.sup.3 represents a single bond or an alkylene 
radical, R.sup.4 represents a monovalent hydrocarbon radical as defined in 
detail in a subsequent portion of this specification for R.sup.1, with the 
proviso that R.sup.4 does not contain ethylenic unsaturation. 
The pendant oxygen atoms O.sub.1, O.sub.2, O.sub.3 and O.sub.4 are part of 
one POM structure. 
Preferably all of the substituents represented by R.sup.2 are hydrogen, 
R.sup.3 is a single bond and R.sup.4 is methyl. 
Preferred reactants and conditions for preparing this type of 
polyorganosiloxane/POM reaction products are described in the accompanying 
examples. 
The polyorganosiloxanes that are reacted with POM/silane reaction products 
to prepare copolymers containing repeating units represented by formulae 
IV and V contain at least one silicon-bonded alkenyl radical such as vinyl 
or 5-hexenyl or at least one silicon-bonded hydrogen atom per molecule. 
The alkenyl radical(s) and silicon-bonded hydrogen atoms can be located at 
terminal or non-terminal positions. The remaining non-terminal siloxane 
units are of the same types discussed in the preceding paragraphs of this 
specification for the polyorganosiloxanes containing hydrolyzable groups 
at the terminal positions. The terminal units contain either three 
monovalent hydrocarbon radicals of the type represented by R.sup.1, with 
the exception of alkenyl, or two of these hydrocarbon radicals and a 
silicon-bonded alkenyl radical or silicon-bonded hydrogen atom. 
Reaction products of POM's with silanes containing vinyl radicals are 
described in the literature, including a communication from P. Judeinstein 
[Chem. Mat., 1992, 4, pp. 4-7]. In accordance with this method an 
alkenyl-substituted silane such as vinyltrichlorosilane is reacted with a 
lacunary POM such as K.sub.4 SiW.sub.11 O.sub.39. The proposed structure 
of the silyl-substituted POM is 
##STR6## 
where the two free valences of each silicon atom are bonded to oxygen 
atoms of a single POM structure. 
The reaction of polyorganosiloxanes containing silicon-bonded hydrogen 
atoms or alkenyl radicals with silyl-substituted POM's containing alkenyl 
radicals or silicon-bonded hydrogen atoms is conducted in the presence of 
a platinum group metal-containing hydrosilation catalyst. It should be 
apparent that either the silane that is reacted with the POM or the 
polyorganosiloxane contains can the alkenyl radicals and the other 
reactant contains the silicon-bonded hydrogen atoms. 
Properties of POM/Polyorganosiloxane Reaction Products 
The physical properties of the POM/polyorganosiloxane reaction products of 
this invention depend upon a number of variables, including the molecular 
weight of the polyorganosiloxane and the cation portion of the POM. The 
cation will also determine the solvents that can be used as the reaction 
medium. 
The physical form of the present reaction products range from powdery 
solids to waxy materials to gels. Products derived from 
polydiorganosiloxanes containing more than about 30 repeating units are 
elastomers in which the POM groups appear to function as a reinforcing 
filler. 
The solid, non-elastomeric reaction products have the potential for use as 
reinforcing fillers in organosiloxane and other types of elastomers. 
Some of the non-elastomeric reaction products are photo reducible, absorb 
ultraviolet (UV) radiation and undergo color changes in the presence of 
X-rays. The electrical and chemical properties of the present materials 
indicate their potential for use in applications requiring electrochromic, 
photochromic and/or electroconductive materials. 
Some of the elastomeric materials exhibit high dielectric constants and low 
dissipation factors. The ability of certain of these properties, such as 
dielectric constant, of these materials to change with repeated testing is 
indicative of their potential for use in electronic memory devices. In 
addition, the elastomers appear to have photochromic and electrochromic 
properties similar to those of the non-elastomeric materials.

EXAMPLES 
The following examples describe preferred embodiments of the present 
POM/polyorganosiloxane reaction products, the properties of these 
materials and methods for preparing them. The examples should not be 
interpreted as limiting the scope of the invention defined in the 
accompanying claims. Unless otherwise specified all parts and percentages 
in the examples are by weight and viscosities are the values measured at 
25.degree. C. 
Preparation of the Polyorganosiloxane Reactants 
The following procedures were used to prepare the polyorganosiloxane 
reactants. 
Polyorganosiloxane Reactant 1 was prepared by charging a glass reactor with 
35 g (0.044 mmol) of a silanol-terminated polydiorganosiloxane having an 
average degree of polymerization of 8.5, 92 g (0.442 mole) of ethyl 
orthosilicate and 0.13 g of potassium acetate. The reactor was equipped 
with a stirring bar, a water cooled condenser and a Dean-Stark trap. This 
mixture was maintained at a temperature of 130.degree.-131.degree. C. for 
three minutes, during which time 2.14 g of volatile materials were 
removed. The temperature of the mixture was then increased to 151.degree. 
C., during which time a total of 0.6 g of volatile materials were 
collected. 
The mixture was then concentrated by heating under reduced pressure while 
the temperature of the liquid was allowed to increase to 147.degree. C. 
The final pressure was 24 mm Hg and a total of 74.49 g of volatile 
material was recovered. The residue was filtered to yield 45.46 g 
(equivalent to 93.18 percent yield based on siloxane reactant) of a water 
white liquid. Analysis using .sup.29 Si NMR indicated a degree of 
polymerization of 12.64. 
Polyorganosiloxane Reactant 2 was prepared by charging a glass reactor 
equipped as described for polyorganosiloxane reactant 1 with 200 g (0.05 
mmol) of a silanol-terminated polydiorganosiloxane with an average degree 
of polymerization of 48.5, 212.7 g (1.02 mole) of ethyl orthosilicate and 
0.41 g of potassium acetate. This mixture was heated to 140.degree. C. 
over a 40 minute period, at which time the temperature of the reaction 
mixture was increased to 160 over 4.1 hours. 6.93 g of volatile materials 
were removed during this period. Heating was then terminated and the 
mixture allowed to remain under ambient conditions for about 16 hours with 
stirring. The mixture was then concentrated by heating it at 156.degree. 
C. and 14 mm Hg until the temperature of the vapor phase decreased to 
27.degree. C. 137.4 g of volatile materials were recovered during this 
period. The residual liquid was filtered to yield 230.25 g of a water 
white liquid containing a triethoxysilyl-terminated polydimethylsiloxane 
having an average degree of polymerization of 52.45. 
Polyorganosiloxane Reactant 3, a trichlorosilyl-terminated organosiloxane 
oligomer with an average degree of polymerization of 9.29, was prepared by 
charging a glass reactor equipped with a nitrogen inlet with 540 g silicon 
tetrachloride (tetrachlorosilane) and 130 cc of dry toluene. A nitrogen 
atmosphere was maintained during charging of the reactor and throughout 
the reaction. A mixture of 251.8 g of a silanol-terminated 
polydimethylsiloxane with an average degree of polymerization of 8.49, 
99.67 g of pyridine and 255 cc toluene was placed in an addition funnel 
and was added to the reactor over a 31 minute period, during which time 
the temperature of the mixture increased from 21.degree. to 59.degree. C. 
The mixture was stirred for 4 hours following completion of the addition. 
The mixture was then filtered to remove the solid that had formed, and the 
filtrate was concentrated by heating for 0.5 hour at 95.degree. C. and 5 
mm Hg. 182.8 g of a pale yellow liquid were obtained. 
Polyorganosiloxane Reactant 4, a trichlorosilyl-terminated 
polydimethylsiloxane exhibiting an average degree of polymerization of 
56.4 was prepared using the general procedure described for organosiloxane 
reactant 4. The reactor was charged with 101.6 g (0.6 mole) of silicon 
tetrachloride and 315.3 g of toluene, and the addition funnel was charged 
with 200 g (0.051 mole) of a silanol-terminated polydimethylsiloxane 
exhibiting an average degree of polymerization of 50.45, 42.5 g (0.54 
mole) of pyridine, and 300 g of toluene. The contents of the addition 
funnel were added to the reactor over a 10 minute period. While the 
temperature of the mixture was controlled using an ice bath, the 
temperature increased from 14.degree. to 22.degree. C. during the first 
four minutes and remained within the range of from 22.degree. to 
25.degree. C. during the remainder of the addition. An additional 130 g of 
toluene was then added through the addition funnel, following which 
stirring was continued for two hours. 
The solid that had precipitated during the reaction was removed by 
centrifugation and extracted once with toluene before being discarded. The 
toluene was combined with the liquid portion of the reaction mixture and 
filtered. The hazy filtrate was concentrated by heating for 0.5 hour at 
100.degree. C. and 5 mm Hg. The resultant liquid weighed 151.53 g, 
equivalent to a yield of 70.9 percent, based on initial 
polyorganosiloxane. The average degree of polymerization of the product 
was 56.4, excluding cyclic materials. 
Polyoxometalate 1--K.sub.8 SiW.sub.11 O.sub.39 .multidot.12H.sub.2 O 
Into a glass reactor equipped with a stirrer, thermometer, water cooled 
condenser and addition funnel were placed 182 g (0.552 mole) of sodium 
tungstate, Na.sub.2 WO.sub.4 .multidot.2H.sub.2 O, 11 g (0.052 mole) of 
sodium metasilicate, Na.sub.2 SiO.sub.3 .multidot.5H.sub.2 O, and 300 cc 
distilled water. The mixture was heated at 93.degree. C. until all of the 
solids dissolved, at which time 195 cc of 4N aqueous hydrochloric acid 
were added over 3 hours. Addition of the acid was halted when the mixture 
became hazy and was resumed when the haziness decreased. Following 
completion of the addition the mixture was heated at the boiling point for 
10 minutes, during which time much of the haziness disappeared. The 
mixture was then filtered to obtain a clear, water white filtrate. 
The filtrate was heated to 70.degree.-75.degree. C., at which time 75 g of 
potassium chloride were added and the mixture was stirred for 15 minutes 
with heating. The mixture was filtered hot and the precipitate was washed 
4 times with cold water. The precipitate was then dried under a nitrogen 
stream. The dried solid weighed 131.95 g, equivalent to a yield of 82.4 
percent. The product was identified by its infra-red and ultraviolet 
spectra and by the use of .sup.29 Si and .sup.183 W nuclear magnetic 
resonance (NMR) spectroscopy. 
Preparation of POM Reaction Products with Polyorganosiloxanes 
(1) Synthesis of the Mixed POM/Polyorganosiloxane of Proposed Structures 
##STR7## 
The oxygen atoms adjacent to any of the "POM1" or "POM2" labels are 
believed to be part of that POM structure. SiW.sub.11 O.sub.39.sup.4- 
4(n--Bu.sub.4 N).sup.+ where n--Bu represents the n-butyl radical. 
A glass reactor equipped with a magnetic stirring bar, and an addition 
funnel with pressure equalizing side arm was charged with 15 g 
(5.times.10.sup.-3 moles) of the POM compound K.sub.8 SiW.sub.11 O.sub.39 
and a mixed solvent containing 404 g acetonitrile and 404 g toluene, and 
the resultant mixture was stirred for 2 hours under ambient conditions. To 
the resultant white slurry 5.31 g of a solubilized mixture of the 
oligomeric chlorine-substituted organosiloxanes (a) Cl.sub.3 
Si--O--(me.sub.2 SiO).sub.11.35 --SiCl.sub.2 --O--(Me.sub.2 SiO).sub.11.35 
--SiCl.sub.3 and (b) Cl.sub.3 Si--O--(Me.sub.2 SiO).sub.11.35 --SiCl.sub.3 
dissolved in 19.81 g of toluene was added over a 29 minute period. The 
molar ratio of a:b, estimated from the .sup.29 Si NMR spectrum of the 
siloxane mixture, was 65:35. Following completion of the addition, the 
addition funnel was rinsed with about 6 g of toluene. 
Stirring of the mixture was continued for another 72 hours, at which time 
the solids that had formed were separated by centrifugation. The liquid 
was removed by decantation and vacuum filtered through a 0.22 micron nylon 
membrane. 2.88 g of inorganic solids, believed to contain unreacted POM 
and potassium chloride, were collected. 
14.18 g, (4.4.times.10.sup.-2 moles) of tetrabutyl ammonium bromide, 
(C.sub.4 H.sub.9).sub.4 NBr were added to the filtrate, and the resultant 
mixture was stirred for 1.5 hours. The precipitate that formed during the 
reaction was collected, washed with a 1:1 volume ratio mixture of 
acetonitrile and toluene, and allowed to dry under ambient conditions. The 
dried material weighed 1.73 g. The liquid portion of the mixture contained 
the major portion of the desired product. This liquid was concentrated for 
45 minutes using a rotary evaporator operating at between 55.degree. and 
57.degree. C. and less than 5 mm Hg. The product was 29.7 g of a creamy, 
opaque/yellow, stiff and tacky material. Most of the solid was then 
redissolved in 206 g of acetonitrile. The hazy translucent solution was 
centrifuged, the yellowish liquid phase decanted and vacuum filtered 
through a 0.22 micron nylon membrane. 
The product was precipitated from the acetonitrile solution by the addition 
of 614 g of deionized water to the liquid phase and separated by 
centrifugation followed by decantation of the solvent. The solid material 
was dried under a stream of dry N.sub.2. 16.98 g of finely divided white 
powder was obtained. This final product was characterized using IR, 
UV/VIS, its .sup.29 Si and .sup.183 W NMR spectra, and low angle laser 
light scattering. The data unequivocally proved that the product contained 
POM structures covalently bonded to the organosiloxane oligomer through 
Si--O--W bonding. 
(2) Synthesis of the POM/Siloxane Reaction Products of Proposed Structures 
##STR8## 
The oxygen atoms adjacent to each of the "POM1" and "POM2" labels are 
believed to be part of that POM structure SiW.sub.11 O.sub.39.sup.4- 
xK.sup.+ 4--xH.sup.+. 
200 g each of acetonitrile and toluene that had been dried over 3 .ANG. 
molecular sieves were placed in a glass reactor equipped with a magnetic 
stirrer. 13.15 g (4.4.times.10.sup.-3 moles) of K.sub.8 SiW.sub.11 
O.sub.39 that had been dried at a temperature of 115.degree. to 
117.degree. C. for about 16 hours was added to the solvent mixture and the 
mixture was stirred for 5 hours. To the white slurry was added, over a 10 
minute period, 4.67 g of a solubilized mixture of the oligomeric 
trichlorosiloxy-terminated organosiloxanes (3) Cl.sub.3 Si--O--(Me.sub.2 
SiO).sub.11.35 --SiCl.sub.2 --O--(Me.sub.2 SiO).sub.11.35 --SiCl.sub.3 and 
(4) Cl.sub.3 Si--O--(Me.sub.2 SiO).sub.11.35 --SiCl.sub.3 and 12.69 g of 
toluene as the solvent. 
The molar ratio of polyorganosiloxane 3 to polyorganosiloxane 4, determined 
using .sup.29 Si NMR data, was 65:35. The funnel used for the addition was 
rinsed with 4.57 g of toluene, and the mixture was allowed to stir for 24 
hours. The solid portion of the mixture (I) was separated by 
centrifugation and discarded. The liquid phase was removed by decantation, 
filtered and the solid material was dried. The dried solid weighed 2.5 g 
and consisted essentially of unreacted POM and potassium chloride. 
The liquid phase was concentrated by heating for about one hour at from 
40.degree. to 45.degree. C. and less than 5 mm Hg pressure. At this time 
15.74 g of an opaque yellowish solid were recovered. The material was 
soluble in water but hydrolytically unstable. It is believed that the 
protons, a by-product of the hydrolysis of the chlorine atoms of the 
initial organosiloxane oligomers, promotes dissociation of the Si--O--W 
bonds and the formation of condensed siloxane gels and SiW.sub.12 O.sub.4 
O.sup.4-. When the product was dissolved in water the initially clear 
solution became hazy upon standing and eventually separated into an 
aqueous phase and a gel phase. 
(3) Synthesis of the POM/Polyorganosiloxane Reaction Product of Proposed 
Structure 
##STR9## 
The four oxygen atoms adjacent to the POM1 label are believed to be part of 
the POM structure K.sup.+.sub.x H.sup.+.sub.4-x SiW.sub.11 
O.sub.39.sup.4-. 
A glass reactor equipped with a magnetic stirrer was charged with 267.97 g 
of acetonitrile and 363 g of toluene. 20 g (6.7.times.10.sup.-3 moles) of 
the POM K.sub.8 SiW.sub.11 O.sub.39 that had been dried for about 16 hours 
at 115.degree.-117.degree. C. were then added, and the mixture was stirred 
for 2.5 hours. At this time a solution prepared by dissolving 19.5 g 
(4.5.times.10.sup.-3 moles) of Cl.sub.3 SiO--(Me.sub.2 SiO).sub.52.45 
--SiCl.sub.3 in 19.4 g of toluene was added in portions to the mixture 
over about a 4 minute interval. Following addition of the siloxane the 
appearance of the reaction mixture changed from a milky opaque slurry to a 
dispersion of a gel-like material that deposited on the wall of the 
reactor. The liquid phase of the mixture became slightly yellow. The 
mixture was stirred at room temperature for another 20.5 hours, during 
which time the yellow color faded, and the dispersed materials appeared to 
diminish in volume. 
The solid and liquid phase materials were separated by vacuum filtration 
through a 0.22 micron nylon membrane filter, the solid phase was washed 
with a mixture of acetonitrile and toluene, and retained. The liquid 
material from the reactor and the washings were combined (696.97 g), 
centrifuged, and the liquid phase (A) was separated by decantation. After 
being dried under nitrogen the retained solids weighed 9.66 g. These 
solids were discarded. 
Liquid phase A was separated into two equal parts. One portion was used to 
prepare the acid form of the POM adduct as follows: 357.99 g of the liquid 
was placed in a 500 ml one neck flask and stripped in a rotary evaporator 
at 35.degree.-40.degree. C. After about half of the solvent had been 
removed, the solution turned hazy, and thickened up. The removal of the 
solvent was discontinued, and the product was a gel-like material with 
thixotropic properties. 
(4a) The second portion of liquid phase (A) was used to prepare the 
tetrabutylammonium salt of the POM/polyorganosiloxane adduct, 
##STR10## 
The four oxygen atoms are believed to be part of a single POM structure 
(C.sub.4 H.sub.9).sub.4 N].sub.x H.sub.4-x SiW.sub.11 O.sub.39 O.sup.4-. 
To 364.7 g of liquid phase (A) was added a solution containing 2.5 g 
(7.75.times.10.sup.-3 moles) of tetra-n-butylammonium bromide dissolved in 
24.5 g of acetonitrile. The solid material that precipitated was isolated 
by decanting the upper portion of the liquid phase followed by filtration 
of the remaining mixture through a 0.22 micron nylon membrane filter. 
After drying under N.sub.2 between 0.5 and 1 g of a white elastomer was 
obtained. 
(5) This example describes preparation of another elastomeric 
POM/polyorganosiloxane reaction product. 
A glass reactor was charged with a mixture of 20 g of acetonitrile and 27 g 
of toluene. To this mixture was added 1.38 g (3.29.times.10.sup.-4 moles) 
of the oligomeric organosiloxane Cl.sub.3 SiO--(Me.sub.2 SiO).sub.52.45 
--SiCl.sub.3 and the resultant mixture was stirred until the 
organosiloxane had dissolved. 1.5 g (5.times.10.sup.-4 moles) of the POM 
K.sub.8 SiW.sub.11 O.sub.39 that had been dried for about 16 hours at 
115.degree.-117.degree. C. were added then added to the mixture, which was 
then stirred for about 16 hours. The solids that had formed during this 
period were separated by centrifuging and decanting the supernatant liquid 
and 0.048 g (1.3.times.10.sup.-4 moles) of tetra-n-butyl ammonium bromide, 
(C.sub.4 H.sub.9).sub.4 NBr were added to the liquid phase. The solution 
become slightly hazy. 
The suspended solids were separated by centrifugation, the clear liquid was 
decanted and concentrated by heating under reduced pressure until it 
exhibited an opaque, milky appearance. About one gram of an elastomer was 
formed following complete evaporation of the liquid phase. The elastomer 
was characterized by IR, reflectance IR to verify the presence of the POM 
structure and UV, to detect the presence of tungsten, using thin films of 
the materials and dielectric measurements. Photographs obtained using a 
scanning electron microscope showed areas of high electron density 
resulting from the tungsten atoms of the POM structures. 
(6) The reaction product of the POM (C.sub.7 H.sub.15).sub.4 N].sup.4+ 
SiW.sub.11 O.sub.39.sup.8- and the organosiloxane oligomer (OC.sub.2 
H.sub.5).sub.3 SiO--(Me.sub.2 SiO).sub.12.64 --Si(OC.sub.2 H.sub.5).sub.3. 
A glass reactor was charged with 20 ml of a toluene solution containing 
6.24.times.10.sup.-4 moles of the SiW.sub.11 O.sub.398- POM anion and a 
ten fold molar excess of the [(C.sub.7 H.sub.15).sub.4 N].sup.+ cation. To 
this mixture was added 0.9 g (6.97.times.10.sup.-4 moles) of (EtO).sub.3 
SiO--(Me.sub.2 SiO).sub.12.64 --Si(OEt).sub.3. 0.16 ml 
(1.87.times.10.sup.-3 moles) of concentrated aqueous HCl were then added. 
No apparent change in the appearance of the initial mixture was observed. 
The mole ratio of the three ingredients SiW.sub.11 O.sub.39 
anion:organosiloxane:HCl was 1:1:3. 
The mixture was heated for 24 hours at the boiling point, at which time it 
was allowed to cool to ambient temperature, and stirred for 48 hours. 
About 12 ml of the liquid was removed by distillation. The remaining 
volatile liquids were removed under reduced pressure at room temperature. 
A gummy white solid was obtained. 
The volatile components were identified by gas liquid chromatography (GLC) 
as primarily ethanol, water, octamethylcyclotetrasiloxane (D.sub.4), 
decamethylcyclopentasiloxane (D.sub.5), and dodecamethylcyclohexasiloxane 
(D.sub.6). The formation of volatile cyclic siloxane products is the 
result of the well known acid catalyzed equilibrium between cyclic and 
linear forms of polyorganosiloxanes that would be expected to occur even 
in the absence of the polyoxometalate. 
The gummy white solid was then placed in an oven at 150.degree. C. for 16 
hours, resulting in a 47 percent weight loss, believed due to acid 
catalyzed formation of cyclic siloxanes, and formation of a gummy, 
slightly yellow, soft solid. .sup.29 Si NMR spectroscopy revealed that the 
POM was covalently attached to the siloxane via Si--O--W bonds and 
indicated the presence of very small amounts of volatile components in the 
final product. The identity of the product was confirmed by its infra-red 
(IR), ultra-violet (UV), .sup.1 H NMR and .sup.13 C NMR spectra, and by 
analysis using a thermogravimetric analyzer and a differential scanning 
calorimeter. 
(7) This example describes the preparation of a POM/polyorganosiloxane 
product using the tetraheptylammonium salt of the POM. 
The proposed structures of the two reaction products are shown in Example 
1, with the exception that the POM portion of the final product is 
SiW.sub.11 O.sub.39.sup.4- 4{(C.sub.7 H.sub.15).sub.4 N.sup.+ }. 
A glass reactor equipped with water-cooled condenser, an addition funnel 
and a stirrer was charged with 20 ml of a toluene solution containing 
3.1.times.10.sup.-3 moles of the SiW.sub.11 O.sub.39.sup.8- anion, and 
3.1.times.10.sup.-2 moles of the [(C.sub.7 H.sub.15).sub.4 N].sup.+ 
cation. To this solution was added dropwise through the addition funnel a 
solution containing (a) 4.31 g of the oligomeric chlorine-containing 
organosiloxanes Cl.sub.3 Si--O--(Me.sub.2 SiO).sub.11.35 --SiCl.sub.2 
--O--(Me.sub.2 SiO).sub.11.35 --SiCl.sub.3 and Cl.sub.3 Si--O--(Me.sub.2 
SiO).sub.11.35 --SiCl.sub.3 in a mole ratio, estimated from .sup.29 Si NMR 
data, of 65:35, and (b) 10 ml toluene. The addition of the organosiloxanes 
required about twelve minutes, and the final mixture had a slight 
yellow/greenish tinge. The solution was stirred for about 16 hours, at 
which time the solvent was removed by evaporation. The residue was a 
mixture of yellow and white solids having the consistency of a gum. The 
yellow portion of the precipitate was dissolved in acetonitrile, leaving 
an insoluble white, sticky, crumbly solid. This material had the 
appearance of a crosslinked organosiloxane gum. The solvent portion of the 
yellow solution was allowed to evaporate, leaving a yellow gummy solid. 
The presence of covalent Si--O--W bonds was verified by .sup.29 Si NMR 
spectroscopy. The material was also characterized by IR spectroscopy. 
(8) Synthesis of a product containing the POM group [(C.sub.7 
H.sub.15).sub.4 N].sub.4 SiW.sub.11 O.sub.39 and the siloxane unit 
##STR11## 
A glass reactor equipped with two addition funnels and magnetic stirring 
bar was charged with 13.38 g (2.25.times.10.sup.-3 moles) of [(C.sub.7 
H.sub.15).sub.4 N].sub.8 SiW.sub.11 O.sub.39 and 50 ml of toluene. This 
mixture was stirred for about 16 hours, at which time a solution of 0.14 g 
of pyridine in 4.87 g of toluene was added to the POM/toluene solution. 
Over a ten minute period 3.16 g (7.6.times.10.sup.-4 moles) of Cl.sub.3 
SiO--(Me.sub.2 SiO).sub.52.45 SiCl.sub.3 and 20.23 acetonitrile were added 
concurrently and separately through the addition funnels into the 
toluene/POM/pyridine solution, and the resulting colorless solution was 
stirred for four days. The solvent and other volatile materials were 
removed under reduced pressure using a water bath at ambient temperature. 
The resulting white, opaque residue had the consistency of taffy and was 
dried under a nitrogen stream. The formation of covalent Si--O--W bonding 
between the POM and the siloxane was confirmed using .sup.29 Si NMR 
spectroscopy. In this procedure pyridine is used as to react with the HCl 
generated as a by-product. 
(9) Second synthesis of a product containing the POM group [(C.sub.7 
H.sub.15).sub.4 N].sub.4 SiW.sub.11 O.sub.39 and the organosiloxane 
portion 
##STR12## 
This synthesis differs from the preceding one in that there is no acid 
scavenger (pyridine) used. 
A glass reactor equipped with a magnetic stirring bar and two addition 
funnels was charged with a solution containing 6.09 g 
(1.02.times.10.sup.-3 moles) [(C.sub.7 H.sub.15).sub.4 N].sub.8 SiW.sub.11 
O.sub.3 and 20 g toluene, and the contents of the reactor were stirred for 
about 16 hours. Over about 90 minutes 1.45 g (3.4.times.10.sup.-4 moles) 
Cl.sub.3 SiO--(Me.sub.2 SiO.sub.52.45 SiCl.sub.3 and 10 g acetonitrile 
were added dropwise to the reactor through separate addition funnels. 
The slightly yellow solution was then stirred under ambient conditions for 
40 hours. The solvent was then removed by evaporation under reduced 
pressure, leaving an opaque gummy-like solid. .sup.29 Si NMR spectroscopy 
confirms that the POM was covalently bound to the organosiloxane 
molecules. The material slowly converted to a crosslinked, insoluble, 
opaque, weak gel containing the POM groups trapped within the network. 
This reaction was believed due to condensation of the terminal ethoxy 
groups.