Note: Descriptions are shown in the official language in which they were submitted.
This invention relates to a hydrolysis-stable polytriazines
of polyfunctional aromatic cyanic acid esters having alkyl or phenyl
radicals or halogen atoms at least in the ortho and ortho'-positions to
at least one -OCN-group, and to a process of their production.
It is known from German Patent No. 1,190,18~ dated April 1, 1965
in the name of Bayer Aktiengesellschaft that high molecular wei~ht poly-
triazines can be obtained by polymerising di-functional or polyfunctional
aromatic cyanic acid esters at an elevated temperature, optionally in the
presence of polymerisation promoters. The polymers are distinguished,
for example, by their remarkable stability at elevated temperatures and
are duroplastic in character after tempering for a sufficiently long period.
The resistance of the polytriazines to acids and various solvents may also
be emphasised. It was not possible to detect any changes in test specimens
that had been stored for thrbe months in benzene, dimethyl formamide,
super high octane petrol, concentrated acetic acid, trichloroacetic acid,
chromic acid, aqueous formaldehyde solution, fuel oil, saturated sodium
phosphate solution and concentrated~hydrogen peroxide (cf. Kunststoffe
58, number 19, pages 827 to g32 (1968)).
In addition,~ it was found by V.V. Korchak et al (cf.
20 Vysokomolekulyarnye soedineniya 1974, number 1, pages 15 to 21) that the
thermal and thermo-oxidative destruction of polytriazines based on aromatic
cyanic acid esters is grea*ly influenced by moisture.
An object of the invention is to improve the polytriazines in
regard to their resistance to hydrolysis.
This object is achieved by using polyfunctional aromatic cyanic
; acid esters having alkyl or phenyl radicals or halogen atoms~at least in the
ortho, ortho'-position to at least one -OCN-group ~or the polytrimerisation
reaction.
:
. . ~ , . . .
~8$~
Accordingly, the present invention relates to a process for the
production of a hydrolysis-stable polytria~ine, wh:ich comprises polytrimer-
ising a polyfunctional aromatic cyanic acid ester having the general formula:
(NCO ~ ~ ~ L ~ CN)d ll
(R)b (R')c
in which
R represents chlorine or bromine, or Cl-Ca alkyl, the two radicals
R not having to be the same, with the proviso that at least the
ortho, ortho'-position to at least one cyanic acid ester group is
substituted by R;
Rl has the same meaning as R;
A represents a si.ngle bond, oxygen, the sulphonyl group, the carbonyl
group, the carboxyl dioxy group, the methylene, ethylene, or 2,2-
propylene group
C~13
( - C - ) or the cyclohexylene radical;
CH3
a represents the number l where e = l, and the number 2 where e = 0;
b represents the number 2;
c represents the number 2;
d represents the number 0 or l; and
e represents the number 0 or l,
with the proviso that a + d = 2 or 3.
The invention also relates to the polytriazines obtained by this . .
process.
The~aromatlc cyanic acid.esters preferably correspond to the
general formula (I):
A (OCN)n (I) :
: : - 2 -
-
in which
A represen-ts an aromatic radical or an aromatic radical interrupted
by bridge members having alkyl or phenyl radicals or halogen atoms
at least in the ortho and ortho'-positions to at least one -OCN-
group, and
n is a number from 2 to ~.
The aromatic cyanic acid esters of formula (I) used in accordance
with the invention may be obtained by the process according to Canadian
Patent number 812,232.
From 1 to 1.1 moles of cyanogen halide ancl 1 mole of a base or
base mixture may be used per phenolic hydroxyl group. The reaction tempera-
tures are in the range of from--~0C to +65C. Suitable basesare inorganic
bases, such as sodium hydroxide, potassium hydroxide, soda, potash or
- 2a -
.
~ ' .
calcium hydroxide, or tertiary amines such as trimethylamine or triethylamine,
whilst suitable solvents or suspending agents include water, alcohols, ketones,
hydrocarbons, chlorinated hydrocarbons or mixtures thereof.
The aromatic cyanic acid esters preferably correspond to the
general formula (II):
~ A ~OCN)d (Il)
Cl~)_ (R ' ~ C
in which
R represents halogen, linear or branched Cl-Cg alkyl or phenyl,
several radicals R not having to be the same, with the proviso
that at least the ortho, ortho'-position to at least one cyanic
acid ester group is substituted by R;
R' has the same meaning as R or represents the group (III):
(OCN)d (111)
Rb
at least the ortho, ortho'-position to at least one cyanic
: acid ester group again being substituted by R'; :
A represents a single bond, an alkylene group with from
1 to 9 carbon atoms optionally substituted by Cl-C4
.
~ ..
,~, .
:
.,, : : .
: ~ ~ . ' . '
all~yl or phenyl, a cycloaliphatic or aroma-tic
5-1ne~bered or 6-me~bered ring optionally interrwpted
~y oxygen, oxygen, th0 sulphonyl group (~S02~ the
carb~nyl dioxy group (-OC0-) or the carbonyl group;
0
a = the number 1 or 2,
b = a number ~rom 2 to 4 9
c = a number ~rom 2 to 4,
d = the number 1 or 2,
e = 0 or 1,
with the proviso that the sum of a and d is
always a number ~rom 2 to 4.
More especially, -the symbols in the formula (II) have
the following meanings:
R represents a chlorine or bromine, or Cl-C4 alkyl;
A represents a single bond, oxygen, the sulphonyl group9
the carbonyl group, the carbonyl dioxy group, the
methylene, ethylene) or 2~2-propylene group
CH3
(- C -), or the cyclohexylene radical;
a = the number 1 where e = 19 and the number 2 where e = 0;
b = the num~er 2;
c = the number 2;
d = the number 0 or 1; and
e = the number 0 or 1 3
with the proviso that a ~ d = 2 or 3.
The following are mentioned as examples of compounds
correspondi:ng to the formula (I):
2,4-dimethyl_1,3-dicyanatobenzene t 2,6-di-tert.-butyl-1,4-
dicyanatobenzene, tetramethyl-1,4~dicyanatobenzene, 2,4,6-
: 1~3-dicyanatobenzene, 2,4,6-trimethyl
trimethyl~ ,3~5-tricyanatobenzene; 3,3',5,5i-tetramethyl-
: Le A 16 471 ~ - 4
.
- . -
4,~ dicyanatodiphenyl, 3,3', 5,5'-tetrachloro-4,4'-
dicyanatodiphenyl, 3,3', 5,5'-tetramethyl-4,4'-
dicyanatodiphenyl ether, 3,3', 5,5'-tetrachloro-4,4'-
dicyanatodiphenyl ~ther, 3,3', 5,5'-tetrabromo-4,4'-
dicyanatodiphenyl ether, 3,3', 5,5'-tetramethyl-4,4'-
dicyanatodiphenyl sulphone, 3,3', 5,5'-tetrachloro-4,4'-
dicyanatodiphenyl sulphone, 3,3', 5,5'-tetrabromo-4,4'-
dicyanatodiphenyl sulphone, 2,2'-bis-(3,5-dimethyl-4-
cyanatophenyl)-propane, 2,2-bis-(3,5-dichloro-4-cyanato-
10 phenyl)-propane and 2,2-bis-~3,5~dibromo-4-cyanatophenyl)-propane.
In cases where it is desired to use particularly pure aromatic
cyanic acid esters with a high stability in storage, it is advisable to
adopt a procedure similar to that described in our Canadian Patents numbers
1,063,129 and 1,055,513 which relate to the production of highly pure
polyfunctional cyanic acid esters. According to Canadian Patent number
1,063,129 di- or polytrialkyl ammonium phenolates (for example polytriethyl
ammonium phenolates) are reacted with an excess of a cyanogen halide in an
organic solvent, optionally in the presence of catalytic quantities of
- trialkylamines such as triethylamine, to form the corresponding aromatic
cyanic acid esters.
According to our Canadian Paten* number 1,055,513 alkali or
alkaline earth metal salts, preferably sodium, potassium, calcium and barium
salts, of aromatic dihydroxy or polyhydroxy compounds are reacted with a
cyanogen halide in a~solvent, optionally in the presence of catalytic
quantities of a tertiary amine.
From 1 to 2 moles and preferably from 1 to 1.4 moles of cyanogen
halide, and from 1 to 1.~ moles, preferably from
,,:
"
~: '
I to L 3 Illole~, oL~ a ~a~e or base mixture, may be used ~or
~v~ry ~)henolic hydroxyl group, -the base or the base m-Lxture
y~ l~eing usecl in a deficit relative -to the cyanoge~
llalide,
Suital)le solven-ts are, tor example, water; lower
alipha-tic alcohols such as methanol, ethanol, propanol,
isopropanol or bu-tanol; aliphatic ke-tones such as ace-tone,
methyl ethyl ketone~ diethyl ketone, methylisopropyl ketone
or me-thylisohutyl ke-tone; alipha-tic or aroma-tic hydrocarbons,
preferred alipha-tic hydrocarbons being the fractions
accumula-ting during distillation o~ naturally occurring
mixtures~ such as pe-troleum ether, light petrol or petrol,
whilst examples o~ aromatic hydrocarbons are benzene~
-toluene and xylenes; aliphatic and aromatic chlorinated
hydrocarbons such as dichloroethane, perchloroethylene,
chlorobenzene or dichlorobenzene; ethers such as diethyl
ether9 diisopropyl ether, dioxane, tetrahydro~uran or
di-sec.-butyl ether; nitrohydrocarbons such as nitromethane~
nitrobenzene or nitrotoluene; amides such as dimethyl
~orm~mide or dimethyl acetamides; and mixtures therao~,
~ Suitable inorganic or organic bases are thosementioned
; in GB-PS 1,007 790.
These processes are generally carried out at temperatures
`~ - in the range o~ ~rom -40C to +65~C and pre~erably at
temperatures in the range,o~ from QC to 30C. In oases
where cyanogen chloride is used, the reaction is preferably
carried out below the boiling point ~13C), although where
cyanogen bromide is u~ed the reaction may even be carried
out at temperatures above 50C.
Tertiary amines, which are used in ca~alytic quantities
(0.001 to 10 % by weigh-t9 more especially 0.001 to l.0 ~0
by weight, based on the alkali or alkaline earth phenolate)
- 6 -
.-, ~ . '
.
in accordance with our Canadian Patent number 1,055J513 correspond to the
general formula:
Rl
N - R2
R3
in which
Rl, R2, R3 represent alkyl, aryl and cycloalkyl radicals which do not hava to
be the same, with from 1 to 36 carbon atoms, more especially with up to 18
carbon atoms, such as for example trimethylamine, triethylamine, methyl
diethylamine, tripropylamine, tributylamine, methyl dibutylamine, dinonyl
methylamine, dimethyl stearylamine, dimethyl cyclohexylamine and diethyl
aniline.
The aromatic cyanic acid esters may be reacted by heating to about
30C - 250CJ preferably to 50C - 200C, optionally in solu~ion and
optionally in the presence of a catalyst or catalyst mixture, to form
partially crosslinked prepolymers which are soluble in organic solvents.
The prepolymers represent polymeric cyanate-group-containing triazines of
liquid, wax-like or solid consistency and are soluble in organic solvents.
They are highly stable in storage. As shown by the IR-spectrum, they have
the band characteristic of the -0-C-N-group at 4.51u in addition to the
triazine struc~ure.
The prepolymers may be converted into high molecular weight
polymers of triazine structure by heating to a temperature of from 120C to
350C, preferably from 150C to 250C, optionally in solution and optionally
in the presence o a catalyst or catalyst mixture. The end products are
substantially insoluble in solvents and are
:
,~
,
'
si~le As shown l)y the IR-spec-tru~, there ~re no
~ther linkage principles in -the ~olymer apart lrom -the
triazine structures
The polytria~ines may of course also be produced in
a sin~le stage.
Suitable catalysts for ~the production of -the prepolymer
and the high molecular weigh-t end polymer with -triazine
structures include acids J bases, salts, nitrogen and
phosphorus compounds 9 ~or example Lewis acids such as
1~) AlC13, BF3, FeC13, TiC14, ZnC12 or SnC14; proton acids
such as HCl or H3P04; aromatic hydroxy compounds such as
phenol, p-nitrophenol, pyrocatechol or dihydro~y napthalene;
sodium hydroxide, sodium methylate, sodium phenolate,
-trimethylamine, triethylamine, tributylamine, diazabicyclo-
(2,2,2)-octane, quinoline, isoquinoline; tetrahydroiso~ui~oline,
tetraethyl ammonium chloride, pyridine-N-oxide, tributyl
phosphine, phospholine- ~3-l-oxa-l-phenyl9 zinc octoate,
tin octoate, zinc napthenate, and mixtures thereof~
The catalysts may be used in ~uantities o~ ~rom 0.001 %
by weight to 10 ~ by weight; based on the prepolymer or on
the cyanic acid ester containing cyanamide groups 9 or i~
desired in even larger quantities.
The aromatic cyanic acid esters or the prepolymers
may be used, in solution in inert solvents such as acetone,
benzene, xylene, chlorobenzene, ethylacetate~ tetrahydro~uran,
dibutyl ether or dimethyl ~ormamide~ or in powder ~orm3 ~or
the produotion o~ coatings on substrates such as metals,
oeramios, glass, earthenware, etc., or, in solution in
organic solvents, as impregnating lacquers or laminating
resins. I~ desired, the prepolymers may be combined with
~illers, pigments, glass ~ibres, metal ~ibres and glass
cloths, and may be used for the production o~ mouldings or
~ Le ~ 16 4?1 ~ _ 8 -
: ~ ~
lamillates Yellow to brown coloured, -transparent end
roducts with ex-treme hardness and a high temperature
rosis-tancc are obtained after hardening, The par-t-lcular
advantage of the poly-triazines obtained in accordance with
the invention9 apart from their high heat resistance,
is the fact -that they are unaffected by hydrolysing chemicals
such as alkalis.
The percentage contents and par-ts quoted in the
following Examples relate to weight unless otherwise
indicated.
EXAMPLE 1
. . _
0.03 % by weight of zinc octoate is added to 15 g of
bis-2,2-(4-cyanato-3,5-dimethyl phenyl)-propane, followed
by hea-ting -to 140C. A clear mel-t is obtained and is kept
at 1~0C ~or 8 hours. A~ter cooling, a prepolymer is
obtained which is wax like at room temperature and which
becomes highly viscous above about 50~C and fluid at above
about 80C, ~D90 1.5520-90~ The IR-spectrum of this
prepolymer shows the band characteristic o~ the -O-C_N-
group at 4.5 ~ and the band characteristic of the s triazine
ring at 6.4 ~ and 7.25 p. Hardening in-to an eætremely
hard, honey-coloured polytriazine takes place over a period
of 6 hours at 200~C.
~ test
The polytriazine thus prepared is not dissolved by
boiling ~or 120 hours in 40 % NaOH, 25 % ammonia solution
or 20 % hydrochloric acid. By contrast, a polytriazine
produced from bis-2~2-(4-cyanatophenyl)-propane is split
. hydrolytically into cyanuric acid and bisphenol A after
~0 only 5 hoursO
Le A 16 471 _ 9 _
,
EXAMPLE 2
., _
0.1 ~0 by weigh-t of zinc octoate is added to 20 g of bis-
2,2-(4-cyanato-3,~-dim0thyl phenyl)-propane~ followed by
heating for 3 hours a-t 150C. A clear yellow-colowred
mel-t is obtained The -temperature is then increased to
180C and left at that level for 3 hours. An extremely
hard, honey-coloured poly-triazine is obtained after cooling
EXAMPLE 3
005 ~ by weight of pyrocatechol and 0.5 % by weight of
diazabicyclo-(2,2,2)-octane are added to 1 kg of bis-2,2-
(4-cyanato-3,5-dime-thyl phenyl)-propane, followed by
heating with stirring for 8 hours at 150C. ~he highly
viscous melt is then poured out. A pale yellow coloured
prepolymer is obtained, I-t is fluid above 80C, nD9
1.5520 90, The I~-spectrum shows the characteristic
bands at 4.5 ~ (-0-C-N) and at 6.4 ~ and 7,25 p (s-triazine).
0.1 ~ by weight of tin octoate is added to 15 g of this
prepolymer, followed by hardening over a period of 3 hours
at 190C to form an extremely hard, light brown poly-triazine.
EX~MPLE 4
0.1 ~ by weight of zinc chloride is added to 10 g of
2,6-di-tertO-butyl hydroquinone dicyanate, followed by
heating for 3 hours to 120C. ~he product obtained is
then kept at 200C for 3 hours~ A hard, yellow brown
coloured polymer is obtained after cooling, showing the
bands characteristic of the s-tria~ine ring at 6,4 ~ and
` 7.25
EXAMPLE 5
20 g of 2,4,6-trimethyl resorcinol dicyanate are
mi~ed with 0.02 ~ by weight of zinc octoate, followed by
heating for 5 hours to 150~C. A prepolymer: solidifying
slowly at room temperature is obtained (IR~spectrum: -C-C-N
Le A 16 471 - 10 -
a-t 4.5 ~, s-triazine ring at ~,4 ~ a:nd 7,Z5 ~). Hardening
of this prepolymer into an extremely ha:rd, brown poly-triazine
takes place over a pe.riod of 2 hours a-t 220C~
EXAMPLE 6
10 g of 2, 3 9 5,6-tetramethyl hydroquinone dicyana-te
are heated for 4 hours to 160C with OoOl % by weight o~
tin octoate, The prepolymer obtained is hard and brittle
at room temperature and highly viscous above 75C.
Hardening of this prepolymer takes place over a period
of 5 hours at 230~Co A very hard, brown polytriazine is
obtainedO
EXAMPLE 7
10 g of bis-2 ~ 2-(4-cyanato-3,5-dichlorophenyl)-propane
are slowly heated to 150~C. After 3 hours the temperature
is increased to 180C and af-ter another hour to 220C.
A~ter a total of 5 hours a brown prepolymer is obtained
with the characteris$ic s-triazine ring bands in the
IR-spectrum~
.
. ~ . .
