Novel polyacrylic esters bearing pendant macrocyclic ethers and electrically conducting compositions comprised thereof

The present invention relates to polyacrylic ester polymers having pendant macrocyclic ethers as well as electrically-conducting compositions comprised thereof.

BACKGROUND OF THE PRESENT INVENTION 
The present invention relates to polyacrylic ester polymers bearing pendant 
macrocyclic ethers. 
Substantial interest in macrocyclic ethers has developed since their 
invention was reported by C. J. Pedersen in the late 1960's. Many of these 
ethers, and in particular those comprising the 18-crown-6 moiety, have 
proved quite useful in the complexing of alkali metal, alkaline earth and 
other cations. 
A number of U.S. patents have issued to C. J. Pedersen and co-workers 
relating to the preparation and use of various crown ethers including U.S. 
Pat. Nos. 3,361,778; 3,562,295; 3,686,225; 3,687,978; 3,856,813; and 
3,873,569. 
Although certain interest has been shown in developing polymeric materials 
which comprise crown ethers, the uses for these materials have tended to 
parallel those of the non-polymerized crown ethers, and little emphasis 
has been placed on the uniqueness which is attributable to a polymer 
matrix. 
Generally, two types of polymers have been produced comprising crown 
ethers, specifically (1) polymers in which the crown ether moiety is 
pendant from the polymer backbone; and (2) polymers in which the crown 
ether moiety is incorporated into the polymer backbone. 
With regard to the former, various disclosures exist regarding the 
complexing behavior of addition polymers bearing macroheterocyclic 
structures as pendant groups including Jaycox, Gary D. et al, J. Polymer 
Sci, 20, 1629 (1982) and Proceedings IU Macromolecular Symposium, U. of 
Mass., Amherst, Mass., July 12-16, 1982, p. 99. 
An example of the latter relates to work wherein a dibenzo-18-crown-6 was 
nitrated in both benzene rings and the nitro groups were reduced. The 
resulting isomeric diamines were then interacted with diacid chlorides to 
provide polyamides. Commonly-assigned U.S. Pat. No. 4,438,251 (issued to 
Herweh) is directed to polyurethane polymers comprising macrocyclic crown 
ethers in the polymer backbone. Reference is also made to the 
incorporation of macroheterocyclic structures into a polymer chain in 
Mathis, L. et al, J. Polymer Sci. A18, 2911 (1980); Gramain, P. et al, 
Ind. Eng. Chem. Prod. Res. Dev., 20, 524 (1981); and Herweh, J. et al, J. 
Polymer Sci., 21, 3101 (1983). 
Concurrent with the noted interests has been the attention afforded the 
development of polymers possessing, in addition to the strength, 
elasticity, plasticity and toughness typically associated with metals, the 
property of electrical conductance. The importance of this objective lies 
in the significance of being able to process such material in the form of 
films, foils, fibers, etc. in accordance with established procedures. 
OBJECTS AND SUMMARY OF THE INVENTION 
It is accordingly one object of the present invention to provide novel 
polymers comprising pendant crown ethers. 
It is accordingly another object of the present invention to provide 
polymeric substrates comprised of polymers having pendant crown ethers, 
the polymers being useful for a variety of purposes. 
It is accordingly another object of the present invention to provide 
polymeric substrates comprised of polymers having pendant crown ethers 
which substrates are useful in the complexing of alkaline earth, alkali 
metal and other cations. 
It is yet another object of the present invention to provide polymeric 
substrates comprised of polymers having pendant crown ethers which, when 
complexed with cation materials or neutral electron acceptor molecules, 
serve as electrically conductive materials. 
In its broadest aspect the present invention relates to a polymerizable 
monomer having the formula: 
##STR1## 
wherein n=1-3, R is hydrogen or methyl, R.sub.1 and R.sub.2 are hydrogen 
or in combination with the macrocyclic ether ring form a phenyl ring and 
wherein at least some of the hydrogen atoms present upon the aromatic 
rings optionally may be replaced by an alkyl group of 1 to 4 carbon atoms. 
Accordingly, the phenyl ring bearing the acrylic ester and the phenyl ring 
formed by R.sub.1 and R.sub.2 may be substituted or unsubstituted. The 
substituents on each or either aromatic ring suitably are lower alkyl 
groups of 1 to 4 carbon atoms. 
In accordance with another aspect of the present invention, there is 
provided a polymerizable monomer having the formula: 
##STR2## 
wherein n=1-3, R is selected from the group consisting of hydrogen or 
methyl and wherein at least some of the hydrogen atoms present upon the 
aromatic rings optionally may be replaced by an alkyl group of 1 to 4 
carbon atoms. 
In accordance with another aspect of the present invention, there is 
provided a polyacrylic ester polymer comprised of a moiety having the 
formula: 
##STR3## 
wherein n=1-3, R is selected from the group consisting of hydrogen and 
methyl and wherein at least some of the hydrogen atoms present upon the 
aromatic rings optionally may be replaced by an alkyl group of 1 to 4 
carbon atoms. 
Yet another aspect the present invention relates to a polyacrylic ester 
polymer comprised of a moiety having the formula: 
##STR4## 
wherein n=1-3, R is hydrogen or methyl, R.sub.1 and R.sub.2 are hydrogen 
or in combination with the macrocyclic ether ring form a phenyl ring and 
wherein at least some of the hydrogen atoms present upon the aromatic 
rings optionally may be replaced by an alkyl group of 1 to 4 carbon atoms. 
Accordingly, the phenyl ring bearing the acrylic ester and the phenyl ring 
formed by R.sub.1 and R.sub.2 may be substituted or unsubstituted. The 
substituents on each or either aromatic ring suitably are lower alkyl 
groups of 1 to 4 carbon atoms. 
In accordance with yet another aspect of the present invention there are 
provided electrically-conductive compositions comprised of a complex of a 
metallic salt and a polyacrylic ester polymer comprised of a moiety having 
the above-identified formulae. 
DETAILED DESCRIPTION OF THE INVENTION 
The polyether ring system used to practice the present invention preferably 
comprises a mono- or diphenylene-18-crown-6 moiety. 
The preferred diphenylene and phenylene-18-crown moieties are identified by 
the following formulae: 
##STR5## 
The polyether alcohols comprising these moieties may be prepared by means 
which are well known in the art. For example, in the case of the dibenzo 
bearing ring system, 3,4-dihydroxybenzaldehyde (a substituted catechol) 
may be interacted with 1,2-bis[2'-(2"-chloroethoxy)ethoxy] benzene 
according to general literature procedures to provide 2,3-(4'-formyl 
benzo)-11,12-benzo-18-crown-6 product. Similarly, if 
1,2-bis(2'-chloroethoxy) benzene or 1,2-bis [2'-(2"-chloroethoxy)diethoxy] 
benzene are substituted for 1,2-bis [2'-(2"-chloroethoxy)ethoxy] benzene, 
the 12-crown-4 or 24-crown-8 moiety, respectively, can be obtained. The 
formyl function can then be reduced to the alcohol form. 
In the case of the monobenzo bearing ring system the 
3,4-dihydroxybenzaldehyde may be interacted with 
1,14-dichlorotetraoxatetradecane according to general literature 
procedures to provide 2,3-(4'-formylbenzo)-18-crown-6. Similarly if 
1,8-dichlorodioxaoctane or 1,20-dichlorohexaoxaeicosane are substituted 
for 1,14-dichlorotetraoxatetradecane the 12-crown-4 or 24-crown-8 moiety, 
respectively, can be obtained. 
Hydroxylated ring substituents must be prepared for use according to the 
present invention in order to ultimately form the acrylic ester monomer. 
These materials are derivable from aldehydes which are commercially 
available, or which are prepared according to literature methods. Primary 
alcohols may be prepared by reacting catechol aldehydes of the formula 
##STR6## 
where R.sub.1 is --COR.sub.5, R.sub.2, R.sub.3, and R.sub.4 are 
independently H or CH.sub.3, and R.sub.5 is H, and then reducing the 
aldehyde to the alcohol after interaction of the catechol to form the 
crown ether. The various alcohols may then be prepared by reduction using, 
for example, sodium borohydride. 
With regard to the acrylic portion of the polymers of the present 
invention, acrylic acid-derived (i.e., where R is hydrogen) and 
methacrylic acid-derived moieties may be employed. For example, 
methacryloyl chloride may be reacted with the alcohol substituent 
discussed above to provide the desired methacrylate monomer. 
The polyacrylic ester polymers of the present invention have been found to 
exhibit highly effective cation-binding ability, especially in contrast to 
the dibenzo-18-crown-6 ether as well as to polymers wherein the crown 
ether structure comprises part of the polymer backbone (e.g., a 
polyurethane as disclosed in commonly-assigned U.S. Pat. No. 4,438,251). 
The procedure described by Pedersen, C. J. et al in Fed. Proc., Fed. Amer. 
Soc. Exp. Biol., 1968, 27, 1305 was employed to determine the extent of 
the formation of complexes between various crown ethers and alkali metal 
salts. The determination was made by means of solvent extraction and UV 
spectral determination of the extracted pictrate ion. Methylene chloride 
was used as the organic phase with the crown ether, and the concentration 
of the alkali and alkaline earth metal hydroxides was 0.01M. The 
concentration of the crown ether was 7.times.10.sup.-4 M in all instances 
except for K.sup.+ (molar ratios of 1/2 and 1/20), Na.sup.+ ( molar ratio 
of 1/2) and Ba.sup.++ (molar ratio of 1/20) where the concentration was 
1.4.times.10.sup.-3 M. The concentration of the picrate was 
7.times.10.sup.-4 M except for K.sup.+ (molar ratios of 1/10 and 1/20) 
where the concentration was 7.times.10.sup.-5 M. The results of the noted 
comparisons are set forth in Table I below, with the results for crown 
ethers A and B having been previously-reported by Herweh, J. E. et al, J. 
Polym. Sci., 21, 3101 (1983): 
TABLE I 
______________________________________ 
Ion-Binding Capability of Various 
Crown Ethers 
Extraction % Based on Picric Acid 
Ba.sup.++ 
K.sup.+ Na.sup.+ Mol 
Mol Ratio 
Crown Mol Ratio Pi/CE Ratio Pi/CE 
Pi/CE 
Ether 1/1 1/2 1/10 1/20 1/1 1/2 1/10 1/20 
______________________________________ 
A 26.4 31.5 34.4 50.1 1.3 1.2 2.6 3.6 
B 20.5 26.0 28.3 49.0 7.1 -- 2.9 4.8 
C 32.1 39.8 52.1 72.3 6.0 8.8 8.1 12.1 
______________________________________ 
A = Dibenzo18-crown-6 
B = Polyurethane having crown ether A within chain 
C = Polymethacrylic ester bearing pendant crown ether A 
The extractive efficiencies of the various crown ethers identified in Table 
I indicates that the polyacrylic ester polymer C of the present invention 
exhibits an overall extractive efficiency greater than the efficiency 
exhibited by the other types of crown ethers (denoted as A and B). The 
particularly noteworthy complexing of K.sup.+ may be due to the formation 
of sandwich type 1:2 complexes between the metal cation and two adjacent 
crown ether moieties which are present as pendant groups along the polymer 
chain. 
The ion-binding ability of the polymethacrylic ester bearing crown ether 
structures was applied to several metal-7,7,8,8-tetracyanoquinodimethane 
(TCNQ) salts that are virtually insoluble in water and in organic 
solvents. The complexation of metal-TCNQ salts with various nonpolymeric 
macroheterocyclics has been reported. Japanese Pat. No. 80-45,641 (CA 93 
186425r (1980)) describes the formation of dibenzo-18-crown-6 complexes 
with alkali metal-TCNQ salts. Such complexes reportedly have high 
electrical conductivities and solubility in organic solvents. 
When a solution of 1,2-dichloroethane and the polymethacrylic ester of the 
present invention bearing crown ether structures was agitated with K.sup.+ 
TCNQ..sup.-, a deep green color rapidly developed in the organic phase. In 
a specific case where the crown ether bearing polymethyacrylic ester 
polymer (1.times.10.sup.-2 M in 1,2-dichloroethane) was contacted with 
6.times.19.sup.-5 mol of K.sup.+ TCNQ..sup.- and the visible spectrum 
recorded after 1 hour, a spectrum was obtained that was consistent in the 
400-750 nm region with that reported by Hertler et al, J. Amer. Chem Soc., 
84, 3374 (1962) for the TCNQ radical anion. Solid complexes, typically an 
intense iridescent green to an iridescent blue-green in color, were 
obtained by stirring a solution of the polymer of the present invention in 
1,2-dichloroethane with an excess of the metal-TCNQ salt (typically at a 
1:2 molar ratio of polymer to metal-TCNQ salt). The soluble complexes were 
isolated from the solvent phase by removal of volatiles in vacuo. 
Conductivity determinations, carried out using the three-probe method in a 
powder compaction cell, gave values that in the case of K.sup.+ and 
Cs.sup.+ were several orders of magnitude lower than that of the 
corresponding metal-TCNQ..sup.- salt alone as noted in Table II. In the 
case of the Cu.sup.+2 (TCNQ..sup.-).sub.2 salt, the conductivity of the 
crown ether bearing polymer solubilized metal-TCNQ salt and the metal-TCNQ 
salt alone were comparable as also noted in Table II below: 
TABLE II 
__________________________________________________________________________ 
Electrical Properties of Metal-TCNQ Salts Solubilized 
via Complexation with a Polymethacrylate Bearing Pendant 
Crown Ether Structures 
Crown Ether (CE) 
Conductivity 
Solubilized Conductivity 
M.sup.+n (TCNQ..sup.-) 
S/cm M.sup.+n (TCNQ..sup.-) 
S/cm 
__________________________________________________________________________ 
K.sup.+ TCNQ..sup.- 
2 .times. 10.sup.-4 
CE(K.sup.+ TCNQ..sup.-) 
2 .times. 10.sup.-8 
Cs.sub.2.sup.+ (TCNQ..sup.-).sub.2 TCNQ 
1 .times. 10.sup.-5 
CE[Cs.sub.2.sup.+ (TCNQ..sup.-).sub.2 
5 .times. 10.sup.-7 
Cu.sup.+2 (TCNQ..sup.-).sub.2 
5 .times. 10.sup.-3 
CE[Cu.sup.+2 (TCNQ..sup.-).sub.2 ] 
5 .times. 10.sup.-3 
__________________________________________________________________________

The invention is additionally illustrated in connection with the following 
Examples which are to be considered as illustrative of the present 
invention. It should be understood, however, that the invention is not 
limited to the specific details of the Examples. 
EXAMPLE I 
Preparation of 4-formyldibenzo-18-crown-6 ether 
A solution of 3,4-dihydroxybenzaldehyde (27.3 g, 0.197 mol) in 500 ml of 
n-butanol was sparged for 0.5 hour with N.sub.2. Sodium hydroxide (15.8 g, 
0.395 mol) was quickly added and the mixture was heated to reflux. To the 
refluxing solution 63.8 g (0.197 mol) of 
1,2-bis[2'-(2"-chloroethoxy)ethoxyl]benzene was added with stirring over a 
period of 75 minutes. Upon completing the addition, the reaction mixture 
was heated at reflux for 3 hours and then cooled to 50.degree.-60.degree. 
C. and acidified with 2.5N HCl. The acidulated reaction mixture was heated 
to reflux and ca. 130 ml of butanol was distilled. Water was added 
dropwise while the distillation was continued--the rates of addition and 
distillate formation being of similar magnitude. 
After ca. 400 ml of distillate had been removed, acetone (200 ml) was added 
and the finely divided tan solid filtered and dried in vacuo in the 
presence of P.sub.2 O.sub.5. The dried reaction product, 31.5 g was 
triturated with boiling benzene and gave 24.1 g (0.062 mol) of 
4-formyldibenzo-18-crown-6, mp 192.degree.-5.degree. C.; .sup.1 H-NMR 
(CDCl.sub.3) 4.0 (m, --OCH.sub.2 CH.sub.2 O--), 6.8-7.5 (m, aryl protons), 
and 9.8 ppm (s, --CHO) of the formula: 
##STR7## 
Preparation of 4-methyloldibenzo-18-crown-6 ether 
Sodium borohydride (1.99 g, 0.053 mol) was rapidly added to a stirred 
slurry of 4-formyl-dibenzo-18-crown-6 (10.2 g, 0.026 mol) in 200 ml of dry 
glyme. The resulting mixture was left to stir at room temperature for 
several days. The reaction mixture was quenched by its addition to 175 ml 
of water. Dilute acetic acid was subsequently added with cooling to the 
resulting weakly basic reaction mixture until it was neutral. The mixture 
was filtered to remove small amounts of insoluble matter and the filtrate 
was concentrated to 1/4 its original volume on a Rota-vap at reduced 
pressure. The concentrate was cooled and the precipitated solid filtered, 
washed with cold water and dried in vacuo to yield 8.91 g (88%) of 
4-methyloldibenzo-1-8-crown-6 ether, m.p. 168.degree.-172.degree. C. of 
the formula: 
##STR8## 
Preparation of 4-methyloldibenzo-18-crown-6 methacrylate 
4-methyloldibenzo-18-crown-6 (12.8 g, 33 mmol) and 128 ml of dry 
dimethylformamide were quickly added to a flame dried reactor and the 
mixture warmed to ca. 50.degree. C. to dissolve the 
4-methyloldibenzo-18-crown-6. Dry benzene (65 ml) and triethyl amine (6.7 
g, 66 mmol) was added and the stirred solution was cooled to 25.degree. C. 
under a nitrogen atmosphere. 
A solution of freshly distilled methacryloyl chloride (4.1 g, 39 mmol) in 
10 ml of dry benzene was added in 5 minutes with stirring and cooling in 
ice water. After 24 hours at room temperature the reaction mixture was 
filtered; the filter-cake washed with ether and dried in vacuo was 
identified as triethyl amine hydrochloride (4.3 g, 95% of theoretical). 
The clear pale yellow filtrate was flash distilled at 0.3 mm (still 
temperature &lt;90.degree. C.) and left a pale tan solid residue. The solid 
residue was triturated with water and filtered. The water insoluble 
filter-cake was dissolved in methylene dichloride (200 ml) and the 
resulting solution dried over molecular sieves. Concentration of the dry 
methylene dichloride solution gave 12.5 g of crude 
4-methyloldibenzo-18-crown-6-methacrylate (83%). The crude product was 
chromatographed over alumina using chloroform/methanol (99:1) as the 
eluant. Analytically pure 4-methyloldibenzo-18-crown-6 methacrylate (8.5 
g, 56%), mp 145.degree.-8.degree. C. was recovered of the formula: 
##STR9## 
Polymerization of 4-methyloldibenzo-18-crown-6 methacrylate 
4-methyloldibenzo-18-crown-6 (7.8 g, 17 mol) was added to 100 ml of dry 
benzene and the stirred solution was heated to reflux. A solution of 
2,2'-azobis[isobutyronitrile] (0.015 g, 0.5 mol %) in ca. 2 ml of dry 
benzene was added and refluxing continued. After ca. 3 hours, a second 
addition of 2,2'-azobis[isobutyronitrile] was made and reflux temperatures 
were maintained for 16 hours. Thin layer chromatography (alumina, 
CHCl.sub.3 /CH.sub.3 OH - 99/1) indicated that most of the following 
monomer had disappeared (polymerized): 
##STR10## 
After concentration to remove solvent a viscous gum remained. This residue 
was dissolved in methylene dichloride and the resulting clear pale yellow 
solution added to 600 ml of ice-cold hexane. The white solid precipitate 
was filtered with suction and the filter-cake washed with fresh hexane and 
dried in vacuo at 60.degree. C. The dried polymer 7.65 g (98%) had a Tg of 
67.degree. C. (by DSC, mid-range on reheat). Anal. Calcd. for C.sub.25 
H.sub.30 O.sub.8 : C, 65.49; H, 6.60. Found: C, 65.46 and 65.27; H, 6.74 
and 6.79. The high and low values for the molecular weight distribution of 
the polymer were about 49,000 and 4,900 respectively. 
EXAMPLE II 
Preparation of 4-formylbenzo-18-crown-6 ether 
A solution of 3,4-dihydroxybenzaldehyde (19 g, 0.138 mol) in 400 ml of 
n-butanol was given a sub-surface sparge with helium for 0.5 hr. The clear 
rust colored solution was treated with 11.7 g (0.293 mol) of sodium 
hydroxide in 30 ml of water. The reaction mixture developed an amber color 
and was heated to gentle reflux while maintaining a helium atmosphere. To 
the stirred gently refluxing solution was added 37.4 g (0.136 mol) of 
1,14-dichloro tetraoxatetradecane. 
Upon completing the addition, the amber colored reaction mixture was 
maintained at reflux for 24 hours. The reaction mixture was cooled to room 
temperature and acidified with 18% hydrochloric acid while cooling in an 
ice bath. A crystalline solid precipitated and was filtered with suction. 
The filter-cake was largely water soluble and was discarded as sodium 
chloride. The filtrate, upon distillation at reduced pressure, left a dark 
brown residual oil. The residual oil was extracted with hot hexane. 
Concentration of the combined hexane extracts left an oily solid 
identified as 4-formylbenzo-18-crown-6 (11.2 g, 0.033 mol); 
'H--NMR(CDCl.sub.3) 3.6 (m, --(OCH.sub.2 CH.sub.2 O).sub.3 --, 3.9 (m, 
ArOCH.sub.2 CH.sub.2 O--), 4.2 (m, ArOCH.sub.2 CH.sub.2 O--), 7.2 (complex 
m, aryl) and 9.8 ppm (s, --CHO) of the formula: 
##STR11## 
Preparation of 4-methylolbenzo-18-crown-6 ether 
Sodium borohydride (0.42 g, 0.011 mol) was added to a solution of 
4-formylbenzo-18-crown-6 (3.7 g, 0.011 mol) in 75 ml of dry glyme. The 
resulting solution was left to stir at room temperature for 68 hours, and 
it was then added to 100 ml of water and neutralized with concentrated 
acetic acid. The neutralized solution was concentrated on a Rota-vap at 
reduced pressure. The liquid concentrate was then extracted with 
chloroform and the combined extracts dried over magnesium sulfate. 
Distillation of the dried chloroform solution left an oil identified as 
4-methylolbenzo-18-crown-6, 1.85 g (0.005 mol); 'H--NMR(CDCl.sub.3) 3.69 
(d, --OCH.sub.2 CH.sub.2 O).sub.3), 2.8 (s, OH), 3.9 (m, ArOCH.sub.2 
CH.sub.2 O--), 4.1 (m, ArOCH.sub.2 CH.sub.2 O--), 4.6 (s, CH.sub.2 OH) and 
6.8 ppm (m, aryl protons) of the formula: 
##STR12## 
The method of Example I is followed to produce the methacrylic ester of 
4-methylolbenzo-18-crown-6-ether and polymerization of the resultant 
4-methylolbenzo-18-crown-6 methacrylic ester is likewise effected 
utilizing the method of Example I. 
The principles, preferred embodiments and modes of operation of the present 
invention have been described in the foregoing specification. The 
invention which is intended to be protected herein, however, is not to be 
construed as limited to the particular forms disclosed, since these are to 
be regarded as illustrative rather than restrictive. Variations and 
changes may be made by those skilled in the art without departing from the 
spirit of the invention.