POLYMERS CONTAINING A REACTIVE AROMATIC SYSTEM AND METHOD FOR THEIR PREPARATION

POLYMERES CONTENANT UN SYSTEME AROMATIQUE REACTIF ET METHODE POUR LEUR PREPARATION

English Abstract

ABSTRACT OF THE DISCLOSURE:
The invention is concerned with polymers containing
structural units of the general formula:
<IMG>
wherein R1 is hydrogen or a methyl group, R2 is an alkyl or
hydroxyalkyl containing 1 to 6 carbon atoms, R4 and R5 are the
same or different and represent hydrogen, an acyl, sulfate
or hydrochloric group, an alkyl containing 1 to 4 carbon atoms or
a -CH2COOH group, with the proviso that R5 can represent an acyl,
sulfate or hydrochloric group only when R4 is hydrogen, or R4 and
R5 together with the nitrogen atom to which they are attached
form a diazo group, Ar is p-phenylene, and x is 1 to 4. The
polymers of the invention are advantageously used as ion exchangers,
catalysts for chemical reactions, and for biological applications.

Claims

The embodiments of the invention in which an exclusive
property or privilege is claimed are defined as follows:
1. A polymer containing structural units of the
general formula:
(III)
<IMG>
wherein R1 is hydrogen or a methyl group,
R2 is an alkyl or hydroxyalkyl containing 1 to 6
carbon atoms,
R4 and R5 are the same or different and represent
hydrogen, an acyl, sulfate or hydrochloric group, an alkyl
containing 1, to 4 carbon atoms or a -CH2COOH group, with the
proviso that R5 can represent an acyl, sulfate or hydrochloric
group only when R4 is hydrogen, or R4 and R5 together with the
nitrogen atom to which they are attached form a diazo group,
Ar is p-phenylene, and
x is 1 to 4.
2. A polymer according to claim 1, wherein R4 is
hydrogen and R5 is an acyl, sulfate or hydrochloric group.
3. A polymer according to claim 1, wherein R4 and
R5 are hydrogen, alkyl containing from 1 to 4 carbon atoms or
-CH2COOH group, or R4 and R5 together with the nitrogen atom
to which they are attached form a diazo group.
4. A polymer according to claims 2 or 3, wherein
R2 is an ethyl group.
5. A polymer according to claims 2 or 3, wherein x
is 1.

6. A method of preparing a polymer according to
claim 1, wherein an acrylate ester of the formula:
<IMG>
wherein R1 is hydrogen or a methyl group, R2 is an alkyl or
hydroxyalkyl containing 1 to 6 carbon atoms, R3 is an acyl,
sulfate or hydrochloric group, Ar is p-phenylene, and
x is 1 to 4, is subjected to a free-radical polymerization in
the presence of an initiator of free-radical polymerization at
or above the decomposition temperature of the initiator to form
a polymer containing structural units of the formula (III) defined
in claim 1, in which R1, R2, Ar and x have the aforesaid
meanings, R4.is hydrogen and R5 is an acyl, sulfate or hydro-
chloric group, which, when required, is further subjected to an
acid hydrolysis and the resulting product is diazotized,
alkylated or reacted with chloroacetic acid.
7. A method according to claim 6, wherein the
polymerization is carried out in the presence of comonomers
selected from the group consisting of acrylamide, methacrylamide,
acrylic acid, methacrylic acid and the esters thereof.
8. A method according to claim 6, wherein the
polymerization is carried out in the presence of comonomers
selected from the group consisting of butadiene, isoprene and
styrene.
9. A method according to claim 6, wherein the
polymerization is carried out in the presence of comonomers
selected from the group consisting of divinylbenzene, methylene-
bisacrylamide and ethylene glycol dimethacrylate.
10. A method according to claim 6, wherein the
polymerization is carried out in the presence of polymer solvents
11

and precipitants.
11. A method according to claim 6, wherein the
polymerization is carried out in a dispersion medium under
formation of porous polymer particles having large inner surface
area.
12. A method according to claim 6, wherein alkylation
of the primary amino group is carried by reaction with formaldehyde.
12

Description

1081395
This application is a division of application
No. 241,036 filed December 4, 1975.
Efforts to prepare new kinds of polymers with built-in
functional groups, which enable chemical modifications of the
polymeric system, lead to syntheses of numerous compounds having
the character of monomers. The invention relates to synthetic
polymers which contain in the side chain a p-phenylenediamine
skeleton enabling manifold chemical modifications of the system,
and to a method for their preparation. l`he aim is to prepare
materials suitable for subsequent application, e.g. as a catalyst
of chemical reaction, biologically active preparation, ion
exchanger, and the like, by a simple subsequent reaction of the
polymers.
Interest in polymers with reactive functional groups,
which are raw materials for numerous products of both technological
and application importance, caused the rapid development of
modified polymeric systems. These polymers are prepared by
modification of the fundamental polymeric skeleton by a subsequent
chemical reaction, on the one hand, and by copolymerization of
suitable monomers with reactive groups capable of further reactions,
on the other.
Polymers preformed in this way may be transformed by
further chemical conversions into materials useful for biological
applications, technical applications, and the like.
Théy were developed materials containing an aliphatic or
aromatic primary amino group in the side chain which may be
used, for example, for further reactions of the bonding character
via diazotizing of the aromatic amino group and the subsequent
coupling with a suitable kind of substrate. However, most of
these systems prefer the one-sided utilization. In addition to it,
several reactions provide imperfectly defined products because
the modification reactions are not quantitative or the
corresponding comonomers have unsuitable reactivity ratios.
-- 1 --
: - . . .

-` ~0~31395
The parent application proposed to provide monomers
containing a p-phenylenediamine skeleton and having the general
formula:
CH2 f Co-(o-cH2-cH2)x-N-Ar-NH-R3 (I)
Rl R2
wherein Rl ishydrogen or a methyl group,
R2 is an alkyl or hydroxyalkyl containing 1 to 6 carbon
atoms,
R3 is an acyl, sulfate or hydrochloric group,
Ar is p-phenylene, and
x is 1 to 4.
The above acrylate esters are prepared in accordance
with the invention of the parent application by blocking the
free primary amino group of an aromatic diamine having the
general formula:
H ( CH2 CH2)x ~N Ar NH2 (II)
R2
in which R2, Ar and x have the aforesaid meanings, to form an
-NH-R3 group in which R is an acyl, sulfate or hydrochloride
group, and reacting the resulting blocked diamine with an
acryloyl or methacryloyl halide.
The starting aromatic diamine may be obtained by reacting
ethylene oxide with an N-alkyl aniline, nitrosating the resulting
N-hydroxyethylated N-alkyl aniline, and reducing the resulting
p-nitroso-N-hydroxy-ethylated N-alkyl aniline. The reaction
of the blocked diamine with the acryloyl or methacryloyl halide
is preferable carried out in anhydrous pyridine to 5C for 1 hour
and at 25-30C for 10 hours, and the acrylate ester thus produced
is recovered by crystallization.
The acrylate esters described in the parent application
are noted for their suitable copolymerization reactivity ratios
-- 2
.: . . . . . . . . :................ .
: ,:: . ~ : -
: . . . - .

~Ol~3g5
with common monomers. They can be prepared as mono- or
bifunctional monomers at the same time and, consequently,
used for preparation of linear polymers soluble in proper
solvents and insoluble crosslinked polymers.
The present divisional application is directed to
polymers containing structural units of the general formula:
I / R
-cH2-f-co-(o-cH2-cH2)x-l-Ar-N (III)
Rl R2 R5
wherein Rl is hydrogen or a methyl group,
R is an alkyl or hydroxyalkyl containing 1 to 6 carbon
atoms,
R4 and R5 are the same or different and represent
hydrogen, an acyl, sulfate or hydrochloric group, an alkyl
containing 1 to 4 carbon atoms or a -CH2COOH group,with the
proviso that R can represent an acyl, sulfate or hydrochloric
group only when R4 is hydrogen, or R4 and R5 together with the
nitrogen atom to which they are attached form a diazo group,
Ar is p-phenylene, and
x is 1 to 4.
Polymers of the above formula (III) in which R is
hydrogen and ~5 is an acyl, sulfate or hydrochloric group, are
prepared by a free-radical polymerization of the corresponding
monomer of the formula~ (I) in the presence of an initiator of
free-radical polymerization at or above the decomposition
temperature of the initiator.
According to a preferred embodiment, the polymerization
is carried out in the presence of comonomers consisting of
monomers of the acrylic or methacrylic series, such as acrylamide,
methacrylamide, acrylic acid, methacrylic acid and their esters,
or of vinyl compounds, such as butadiene, isoprene and styrene.
- .
.

108139S
The polymerization is advantageously carried out in the
presence of polymer solvents and precipitants or in a dispersion
medium under formation of porous polymer particles having large
inner surface area.
The invention enables to prepare a polymeric system,
the chemical reactivity of which given by the conjugated
nitrogen system allows to perform several reactions leading to
products with specific properties. With respect to advantageous
copolymerization reactivity ratios, especially with acrylates and
methacrylates, materials of the defined structure with high
content of reactive groups may be prepared. The copolymers may
be indeed prepared also with other types of monomers, as with
styrene, divinylbenzene and their derivatives, isoprene,
butadiene, and the like.
The character of the reactive system prefers namely
copolymerizations with monomers of hydrophilic nature, e.g. with
esters containing hydroxyl group in the side chain, i.e. esters
j of glycols, polyglycols or glycerol, with amides, i.e. acrylamide,
methacrylamide, or N-substituted acrylamides and methacrylamides,
and naturally, with methacrylic and acrylic acids.
The preparation of copolymers in the form of a three-
dimensional network by copolymerization with multifunctional
monomers, as for instance with divinylbenzene, ethylene glycol
dimethacrylate or methylenebisacrylamide, leads to insoluble
homogeneous or heterogeneous copolymers. In the presence of a
suitable solvent system, polymers with large inner surface area
and porosity are formed, which properties predetermine these
ma-terials for broad application, namely those prepared in the
form of small spherical particles for chromatographic and
catalytic purposes and for ion exchange.
Polymers performed in this way may be transformed by
further chemical conversions into materials useful for
biological and technical applications.
-- 4

1081395
Thus, polymers of the formula (III) in which R4 and R5
are hydrogen, alkyl containing 1 to 4 carbon atoms or -CH2COOI~
group, or R4 and R5 together with the nitrogen atom to they are
attached form a diazo group, can be prepared by subjecting a
preformed polymer of the formula (III) in which R4 is hydrogen
and R5 is an acyl, sulfate or hydrochloric group to an acid
hydrolysis and subjecting the resulting product to diazotization,
alkylation or reaction with chloroacetic acid.
The reactive site is, for example, a primary aromatic
amino group which may be diazotized and used in coupling reactions
with various components.
Alkylation of the primary amino group may be carried out,
for example, by reaction with formaldehyde (see Example 9) and
leads to an aromatic tertiary alkylamine built into the polymeric
skeleton.
The formation of a polymeric derivative of aminodiacetic
acid is effected by reaction of the polymer with chloroacetic
acid.
Polymers according to the invention may be advantageously
used as ion exchangers, catalysts of chemical reactions and for
biological applications.
The synthesis of monomers and polymers containing a
p-phenylènediamine skeleton according to the inventions in the
parent and divisional applications will now be further illustrated
with reference to the following non-restrictive examples.
Example 1
N-Ethyl-N-(2-hydroxyethyl)-p-phenylenediamine (560 g) is
dissolved in 2 1. of water at 45C, 230 g of acetanhydride is
added under stirring and the mixture is neutralized with sodium
hydroxide to the alkaline reaction (pH - 9). After dilution with
three volumes of water, a crystalline product (m.p. 133C) is
. . .... - . . . .

~ ,` 1081395
; obtained, which is further reacted with methacryloyl chloride
(10% excess) in the medium of anhydrous pyridine. Methacryloyl
chloride is added into the reaction mixture at 5C within one hour
and the temperature is then maintained at 25-30C under stirring
for 10 hr. After dilution with 5 volumes of water, the oil
separates which gives by crystallization from toluene and
ethanol-water mixture the crystalline product (m.p. 93-94C).
Example 2
The monomer is prepared according to Example 1, with the
distinction that acetate, sulfate or hydrochloride of N-ethyl-
N-(2-hydroxyethyl)-p-phenylenediamine is used as the starting
material and allowed to react with methacryloyl chloride according
to Example 1.
Example 3
.
N-Ethylaniline (0.5 mole) is mixed with 0.6 mole of
ethylene oxide in an autoclave, which is then sealed, pressurized
with nitrogen to 30 atm and heated up to 130C within 2 hr.
Ethoxyethylated product is obtained in the yield of 95% related
to the starting N-ethylaniline. This product is subjected to
nitrosation at the temperature 5C with sodium nitrite solution,
then reduced with tin in hydrochloric acid and, eventually,
subjected to the methacrylation process according to Example 1.
Example 4
N-Ethyl-N-(2-methacryloyloxyethyl)-N'-acetyl-p-
phenylenediamine (5 g) is dissolved in 10 g of Methylcellosolve
and 0.01 g of azobisisobutyronitrile is added. The mixture is
flushed with nitrogen and polymerized at 60C. The resulting
polymer solution is diluted and precipitated into ether. The
polymer is soluble inMethylcellosolve*,acetone and diluted
hydrochloric acid.
* Trademark
-- 6 --
~.' '
.

-` 1081395
Example 5
_
N-Ethyl-N-(2-methacryloyloxyethyl)-N'-acetyl-p-
phenylenediamine (2.6 g) is mixed with 2.7 g of ethylene glycol
monomethacrylate and 0.1 g of azobisisobutyronitrile.
Polymerization at 50 C gives a hard glossy material.
_xample 6
N-Ethyl-N-(2-methacryloyloxyethyl)-N'-acetyl-p-
phenylenediamine (1 g) is dissolved in 4 g of methyl methacrylate
and 1.3 wt. % of azobisisobutyronitrile is added. The mixture is
sealed in an ampoule under nitrogen and gives after polymerization
at 50C for 10 hours a glassy polymeric plug.
Example 7
N-Hydroxyethyl-N-(2-methacryloyloxyethyl)-N'-acetyl-p-
phenylenediamine (1.5 g) is dissolved in 4.5 g of ethylene
glycol monomethacrylate and 0.006 g (i.e., 0.1 wt. ~) of azo-
bisisobutyronitrile is added. The mixture is transferred into a
polymerization mold formed by two planparallel plates. The
polymer resulting after polymerization at 60C for 8hrhas a
form of a homogeneous plate.
_xample 8
A polymerization mixture consisting of 31.9 g of
ethylene glycol dimethacrylate, 29.4 g of ethylene glycol mono-
me-thacrylate, 20.4 g of N-ethyl-N-(2-methacryloyloxyethyl)-N'-
acetyl-p-phenylenediamine and 0.82 g (1 wt. %) on monomers of
azobisisobutyronitrile is polymérized with addition of 98.5 g
of cyclohexanol and 9.7 g of dodecanol in a medium consisting
of 600 g of watèr and 6 g of polyvinylpyrrolidone in a reactor
at the temperature 50C for 2 hr and at 65C for further 8 hr.
Porous gel particles are obtained which exhibit the specific
surface area 150 m2/g.

~081395
Example 9
The polymer prepared by the procedure described in
Example 8 (5 g) was subjected to acid hydrolysis in diluted
hydrochloric acid (l : l) by boiling for 30 min. This gel is
mixed with 50 ml of 98% formic acid and 2 ml of 37% aqueous
solution of formaldehyde is added under cooling. After 1 hr of
stirring at the ambient temperature, the mixture is boiled (at
100 C) for 24 hr. The resulting gel - alkylated product - is
washed with water and ethanol and dried.
Example 10
Diazotizing and coupling with 2-naphtol-3,6-sulfonic
acid.
Diazotizing. The gel prepared by the procedure described in
Example 8 and subjected to the acid hydrolysis described in
Example 9 was washed and afterwards dispersed in hydrochloric
acid 1 : 2. The suspension is cooled to -10C and a 10% solution
of sodium nitrite is added under vigorous stirring within l hr
in a 1.5 fold amount on NH2 groups of the polymer. After
addition of the whole amount, the mixture is stirred at the same
temperature for another 15 min. The gel is then filtered and
thoroughly washed with water and five times with 0.5N HCl.
Coupling. An aqueous solution of 2-naphtol-3,6-sulfonic acid
is poured into the filtered gel at 5C; -the resulting mixture has
pH 1.5 - 2. The mixture is alkalized with borax under stirring;
coupling takes place at pH 7 , 8 which exhibits itself by turning
the gel black the mixture is stirred for another 5 hr. On
completion of the reaction, the gel is thoroughly washed
with water, lN KOH, water lN H2SO4, water, and ethanol
alternatively as long as the washing liquid is no longer colored.
The product is dried from ethanol and characterized by the
amount of SO3H groups in the polymer.
-- 8

` 1081395
_xample 11
Reaction with chloroacetic acid
The gel after acid hydrolysis which was washed until
the washing water was neutral is dispersed in a solution of
sodium chloroacetate and sodium carbonate (1 mole of chloro-
acetate and 0.5 mole of carbonate, the solution saturated at
70C). Twenty fold excess of chloroacetate on amount of NH2
groups is used. The mixture is stirred in an inert atmosphere
at 95C for 8 hr. After cooling, the gel is filtered and
thoroughly washed with lN HCl and water and dried from ethanol.
The product is characterized by the presence of functional groups
/ CH2-COOH in the polymer.
-N
CH2-COOH
g
~:
:
_ ........... . - ~ .
- : , . : ' . ,