Note: Descriptions are shown in the official language in which they were submitted.
`: 2~30~ ~
. ,
HOECHST AKTIENGESELLSCHAFT HOE 92/F 020 R Dr~AC/PP
`;;~ Description
'.
Aromatic copolyamides, processes for their preparation
and structures formed therefrom
The invention relates to novel aromatic copolyamides of
the dicarboxylic acid-diamine type, which can be spun
from their solutions in organic ~olvents, and also to
sh~ped structures produced therefrom, such as fibPrs,
films and coatings which have a very high initial modulus
(modulus of elasticity), and to processes for their
` 10 preparation.
~;
- -
; As is known, aromatic polyamides (aramids) are raw
- materials which have high ~tability to heat and high
chemical stability as well as low combustibility. Thus,
for example, fibers and films composed of such raw
materials have very good mechanical properties, such as
high strength and a high initial modulus (modulus of
elasticity) and are very suitable for industrial fields
of application - for example for reinforcing plastics or
~ as filter materials.
:.~
It is known that filaments or fibers composed of polyara-
mides which have high strengths and a high initial
~-~ modulus can be produced if the amide bonds to ~he aromat-
ic nuclei are oriented coaxially or virtually parallel to
one another, as a result of which rigid, rod-shaped
polymer molecules are formed.
A typical polyamide of this type is, for examplel poly(p-
phenyleneterephthalamide). Filaments composed of this
material are descxibed, for example, in German
Patent 22 19 703.
,'
This polyamide has a number of advantages, but its
.; preparation and its processing are very difficult.
Because of the insolubility in polar organic solvents -
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- 2 -
and specifically also in the presence of inorganic salts,
such as calcium chloride or lithium chloride, as
solubilizing agents, this polymer will precipitate out of
the reaction medium shortly after it has formed. It must
be isolated, washed, ~ried and then redissolved in a
spinning solvent. The preferred solvent for the prepar-
ation of the spinning solutions is concentrated sulfuric
acid, which gives rise to particular problems in relation
to handling (safety at work, corrosion) and waste
disposal.
Attempts have therefore been made to circumvent these
difficulties by developing copolyamides which have good
solubility in the known amide solvents and which can also
readily be spun and the filaments of which, after
stretching, are distinguished by high strength values and
initial moduli.
Thus, for example, copolyamides obtained from tereph-
thalic acid, p-phenylenediamine and 3,4~-diaminophenyl
ether, which in amide solvents yield isotropic solutions
which can readily be spun, have been described in German
Patent 25 56 883 and in German Offenlegungsschrift
(German Published Specification) 30 07 063. As a result
of very high stretching, the filaments acquire high
strengths and moduLi. Here it is the meta orientation and
the oxygen atom which give rise to the increased solubil-
ity. However, there is still a need for aramids which can
be processed from known amide solvents to give fibers
which h~ve high strengths and moduli.
It has now been found that selected aromatic copolyamides
of high molecular w ight can be processed to give shaped
structures which arP distinguished by surprisingly good
mechanical properties, such as high tear strengths, high
initial moduli and low elongation at break.
~_ 3 _ 2~
The object on which the present invention i5 based is,
therefore, to provide further aromatic copolyamides which
are distinguished by good solubility in polyamide
~ solvents and by good gpinnability and which can be
: 5 processed to give shaped structures which have good
; mechanical properties.
.
The copolyamides according to the invention are charac- terized by the presence of selected aromatic diamine
components in selected proportions.
~:`
The present invention relates to aromatic copolyamides
which are soluble in organic polyamide solvents and have
an inherent viscosity of at least 3.5 dl/g, in particular
at least 4.5 dl/g, measured at 25C in solutions of
O.25 % by weight of copolymer in N-methylpyrrolidone,
~ 15 containing the recurring structural units of the formu-
~ lae Ia, Ib, Ic and optionally Id
,' :
OC-Rl-CO-NH-R2 NH- I (Ia),
.-'
- O C - R I - C O - N H~ X~LN H
~.
::;
':
~-OC-RI-CO-NH ~ Y ~ r ~ NH3
:.
:: 20 ~ - Oc - Rl~ C 0 ~ N H - R3- N H ] (Id)
" . ~
~ .
- 4 -
in which at least 80 mol ~ of all radicals R1, with
~ respect to the amount of these radicals in the copolymer,
- are an unsubstituted divalent aromatic radical, the
~alency bonds of which are in the para-posit$on or in a
comparable coaxial or parallel position with respect to
one another, and up to 20 mol ~ of all radicals R1, with
respect to the amount of these radicals in the copolymer,
are an unsubstituted divalent aromatic radical, the
valency bonds of which are in the meta-position or in a
comparable angled position with resp~ct to one another,
R2 is an unsubstituted divalent aromatic radical, the
valency bonds of which are in the para-position or
. in a comparable coaxial or parallel position with
- respect to one another,
: 15 X is a group of the formula -S-, -SO2-, -CO- or, in
particular, -O-,
Y assumes one of the definitions given for X, in
particular -O-, and
R3 is a radical which differs from R2 and is of the
formula II and/or of ~he formula III and/or of the
formula IV and/or of the formula V
.. ~ _ (II), ~CO - NH~ (III),
Hal
.
~ (IY), ~ (v)l
in which Hal is a halogen atom and R4 is Cl-C6-alkyl,
Cl-C6-alkoxy and/or halogen, and the proportion of recurr-
ing structural units Ia, Ib, Ic and Id, with respect to
the sum of these structural units in the copolymer, is
within the following limits:
- 5 ~
: recurring s~ructural unit of the formula Ia: 40 to
65 mol %, preferably 45 to 55 mol %;
-~ recurring structural unit of the formula Ib: 5 to
55 mol %, preferably 35 ~o 45 mol %;
recurring structural unit of the formula Ic: 5 to
35 mol ~, preferably 5 to 25 mol %; and
recurring structural unit of the formula Id: 0 to
30 mol %, prefera~ly 0 or 5 to 20 mol %.
If a copolymer comprises radicals in the meta-position,
: 10 such as radicals R1 or radicals of the formula IV in the
meta-position, the amount of the recurring ~tructural
units of the formula Ib preferably ranges within the
lower range of the indicated amount, for example 5 to
30 mol %.
If the copolymer according to the invention comprises
recurring structural units of the formula Id, in particu-
lar those which comprise radicals of the formula IV, the
:~ amount of said units is preferably 5 to 15 mol ~ and very
particularly preferably 5 to 10 mol %, with respect to
~- 20 the sum of ~he structural units Ia, Ib, Ic and Id.
Structural units of the formula Id can also comprise
different radicals of the formulae II to V, ~or example
radicals of the formula III and V, IV and V or III, IV
:: and V.
If any radicals are divalent aromatic radicals the
valency bonds of which are in the para-position ox in a
comparable coaxial or parallel position with respect to
one another, said radicals are mononuclear or polynuclear
- aromatic hydrocarbon radicals or heterocyclic-aromatic
radicals, which can be mononuclear or polynucl~ar. In the
~ case of heterocyclic-aromatic radicals, said radicals
; comprise, in particular, one or two oxygen, nitrogen or
; sulfur atoms in the aromatic nucleus.
:~
~ 6 - 2 ~
Polynuclear aromatic radicals can be fused with one
another or linearly bonded to one another via C-C bonds
~ or via a -CO-N~- group.
- The valency bonds which are in a coaxial or parallel
position with respect to one another are in opposing
directions. An example of coaxial bonds in opposing
directions are ~he biphenyl-4,4'-ene bonds. Examples of
parallel bonds in opposing directions are the naphthalene
1,5- or 2,6-bonds, whilst the naphthalene 1,8-bonds are
parallel and in the same direction.
Examples of preferred divalent aromatic radicals, the
valency bonds of which are in the para-position or in a
comparable coaxial or parallel position with respect to
one another, are mononuclear aromatic radicals which have
free valencies in the para-position with respect to one
another, in particular 1,4-phenylene, or binuclear, fused
aromatic radicals which have parallel bonds in opposing
directions, in particular 1,4-, 1,5- and 2,6-naphthylene,
or binuclear aromatic radicals which are linked Yia a
C-C bond and have coaxial bonds in opposing directions,
in particular 4,4'-biphenylene.
P~rticularly preferred radicals R1 and R2 are
1,4-phenylene.
If any radicals denote divalent aromatic radicals which
have ~alency bonds which are in the meta-position or in
~ a comparable angled position with respect to one another,
"! said radicals are mononuclear or polynuclear aromatic
hydrocarbon radicals or heterocyclic-aromatic radicals,
which can be mononuclear or polynuclear. In the case of
heterocyclic-aromatic radicals, said radicals comprise,
in particular, one or two oxygen, nitrogen or sulfur
atoms in the aromatic nucleus.
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: ~ - 7 - 2~31~
Polynuclear aromatic radicals can be fused with one
another or can be linked to one another via C-C bonds or
via bridge groups, such as, for example, -O-, -CH2-
~-CO-NH-, -S-, -CO- or -SO2-.
:
Examples of polynuclear aromatic radicals in which the
valency bonds are in an angled position comparable to the
: meta-position are 1,6-naphthylene, 2,7-naphthylene or
3,4'-biphenylene.
A preferred example of a mononuclear aromatic radical of
this type is 1,3-phenylene.
~ Examples of Hal substituents in radicals of the
formula II or Y ar~ bromine and in particular chlorine.
R4 is preferably methoxy, and in particular methyl.
: In order to prepare the copolyamides comprising the
~ 15 recurring structural units Ia, Ib, Ic and, optional-
ly, Id, a dicarboxylic acid dichloride of the formula X
is appropriately reac~ed with a mixture of the diamines
of the formulae VI, VII, VIII and, optionally, IX
CIOC-RI-COCI (X), H2N-R2-NH2 (VI),
~ ~ NH2 (VII) 2N ~ r ~ r ~ NH2
~ H 2 N - R 3- N H 2(IX)~
in which the radicals Rl to R3 as well as X and Y have the
meaning defined further above.
The dicarboxylic acid dichloride of the formula X and the
individual diamine types can also be used in the form of
- 8 - ~ a ~
mixtures.
For this reaction, the proportions of the diamines YI,
VII and VIII and, optionally, IX are in each case to be
chosen such that polyamides are formed which have the
above-defined proportions of structural units of the
formulae Ia, Ib, Ic and, optionally, Id.
It is self-evident to a person skilled in the art that
the sum o~ all structural units derived from aromatic
acids and the sum of all structural units derived from
aromatic amines are essentially identical, i.e. that they
differ by at most about 1 %, preferably by at most 0.2 ~,
and in particular are identical within the framework of
the practical measurement and metering possibilities.
The molecular weight of the polyamides formed can be
controlled, inter alia, via t~e selection of ~he propor-
~ions of aromatic acids to aromatic amines. These selec-
tion criteria are known to those skilled in the art in
the polycondensation field.
Examples of suitable aromatic dicarboxylic acids from
which the dicarboxylic acid dichlorides of the formula X
are derived are naphthalene-1,4-dicarboxylic acid,
naphthalene-1,5-dicarboxylic acid, naphthalene-2,6-
dicarboxylic acid, biphenyl-4,4'-dicarboxylic acid
acid and in particular terephthalic
acid.
~ Up to 10 mol ~ of the dicarboxylic acid dichlorides can
-~ also be derived from divalent aromatic meta-radicals.
Examples of acids from which such dicarboxylic acid
dichlorides are derived are naphthalene-1,6-dicarboxylic
acid, naph~halene-1,7-dicarboxylic acid, naphthalene-~,7-
dicarboxylic acid, biphenyl-3,4~-dicarboxylic acid and in
particular isophthalic acid.
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- 9
Examples of suitable diamines of the formula VI are
naphthalene-1,4-diamine, naph~halene-1,5-diami.ne, naph-
thalene-2,6-diamine, benzidine and in particular
p-phenylenediamine.
5 The diamines of the formula VII (3r4~-diaminodiphenyl
ether) and of the formula VIII (1,4-bis-(4-aminophenoxy)-
benzene) are known per se.
Examples of suitable diamines of the formula IX are 2-
r chloro-1,4-phenylenediamine, 4,4~-diaminobenzanilide and
10 m-phenylenediamine, 3,5'-dimethylbenzidine, 3,5'-di-
chlorobenzidine or 3,5~-dimethoxybenzidine.
The copolymeri2ation of the monomer compounds described
above is generally carried out as solution
polymerization.
: 15 To this end, the aromatic monomer compounds to be reacted
with one another are as a rule dissolved in an organic
solvent. The organic solvent preferably comprises at
; least one solvent of the amide type, such as, for ex-
ample, N-methyl-2-pyrrolidone, N,N-dimethylacetamide,
20 tetramethylurea, N-methyl-2-piperidone, N,N'-dimethyl-
ethyleneurea, N,N,~',N'-tetramethylmaleimide, N-methyl-
caprolactam, N-acetylpyrrolidine, N,N-diethylacetamide,
N-ethyl-2-pyrrolidone, N,N'-dimethylpropionamide, N,N-
dimethylisobutylamide, N-methylformamide or N/N~-dimeth-
25 ylpropyleneurea. The preferred organic solvents N-methyl-
2-pyrrolidone, N,N-dimethylacetamide and a mixture of
these compounds are of importance for the process acGord-
ing to the invention.
. .
- In a preferred embodiment of the solution polymerization,
the aromatic monomer diamines are dissolved in an amide
solvent. The solution thus obtained is then mixed with
the at least one aromatic monomer compound in the form of
an aromatic dicarboxylic acid dihalide, with vigorou6
,
..
2 ~
-- 10 --
stirring, in order to initiate the copolymerization.
In this process the amide solvent is used not only as
solvent for the aromatic monomer compounds and the
aromatic copolyamide obtained therefrom but also as acid
acceptor for a hydrogen halide, for example for hydrogen
chloride, which is formed as a by-product of the copoly-
merization of the aromatic monomer compounds. In some
cases it can be advantageous to use an additive which
promotes the solubility, for example a metal halide of
one of the metals of Group I or II of the Periodic Table,
which halide is added to the copolymerization mixture
before, during or after the copolymerization.
Examples of such additives are alkali metal halides, such
as lithium chloride, or alkaline earth metal hali~es,
such as calcium chloride.
The polycondensation temperatures for the solution
polymerization are usually between -20C and +120C,
preferably between ~10C and +100C. Particularly good
results are obtained with reaction temperatures of
between +10C and +80~C.
~,
~i The sum of the concentrations of the aroma~ic monomer
compounds in the polymerization mixture solution can be
adjusted taking into account the desired degree of
polymerization, the desired viscosity of the polymeriza-
tion mixture, the nature of the aromatic monomer com-
pounds used, ~he nature of the solvent used nd the
desired polymerization temperature. The most fa~orable
; sum of the concentrations can be determined on th~ basis
of a number of preliminary experiments for the course of
the polymerization.
Polycondensation reactions are preferably ~arried out in
such a way that 2 to 15, preferably 5 to 12, % by weight
of polycondensation product are present in the solution
.
~ ' :' . ,
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; ~ 2 ~ ~ 3 Il~J
after the reaction i5 complete. Particularly good results
; are obtained with concentrations of 5.0 to 8 % by weight.
r~ The molecular weight of the polymer, and thus also the
~- viscosity of the reaction batch, increase in the course
; 5 of the polycondensation reaction.
:;,
An adequate molecule chain length is reached if the
viscosity of the polymer solution obtained from the
polycondensation reaction corresponds to an inherent
viscosity of the polymer greater than 3.5, preferably
~` 10 greater than 4.5 and particularly preferably greater than
S.0 dl/g, in particular 5.5 to 8.0 dl/g.
` Inherent viscosity is understood to mean the expression ~`
In ~rel
" ~, ~7 inh
c
In this expression, ~rel iS the relative viscosity and
c the concentration used, in g/100 ml.
. :,
,;~.
For the purpo es of the present invention, it is deter-
mined for solutions of, in each case, 0.25 ~ of polymer
in N-methylpyrrolidone at 25C.
;~'
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Insofar as it is used to prepare the aromatic polyamides
according to the invention which have been described
,
above, ~he process for the preparation of aromatic
polyamides which has been outlined and is known per se is
~' 25 also a ubject of the invention.
Y'
If the polymer solution has reached the viscosity re-
quired for further processing, the polycondensation
reaction can be stopped in the conventional manner by
' adding monofunctional compounds, such as, for exampleJ
acetyl chloride. ~he hydrogen chloride formed, which is
:,
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- - 12 -
bound in salt form to ~he amide solvent, can then be
neutralized by adding basic substances.
Substances suita~le for this purpose are, for example,
lithium hydroxide and calcium oxide, but in particular
calcium hydroxide.
. ,
The aromatic copolyamide obtained on carrying out the
process according to the invention can be separated off
from the copolymerization mixture by means of a separa-
tion process, for example by precipitation. In order to
prepare a solution for shaping the copolyamide, the
aromatic copolyamide obtained in this way is then dis-
solved in a suitable organic solvent, this process being
designated the dissolving process for the preparation of
the shaping solution.
.,
r'15 However, in those cases in which the solution polymeriza-
tion process is used to prepare the aromatic copolyamide
according to the invention, the copolyamide is completely
-dissolved in the solvent for the polymerization, because
it is outstandingly soluble in said solvent. Therefore,
if the process according to the invention is used indus-
-~trially it is advantageous to use the mixture obtained
from the polymerization immediately as shaping solution
for the aromatic copolyamide.
.~ .
The aromatic copolyamide according to the invention is
outstandingly soluble in an organic solvent, for example
.~in organic solvents of the amide type, and has outstand-
ing resistance to heat and superior resistance to chemi-
cals. The aromatic copolyamide according to the invention
is particularly useful for the production of diverse
:~30 shaped articles, for example fibers, films and coatings,
which are likewise a subject of the invention.
!Within the framework sf this description the term
"fibers" is to be understood in its broadest meaning;
;, :
- 13 -
; thus, the term also covers, for example, filaments or staple fi~ers of any desired denier.
Within the framework of this description, the term
"films is likewise to be understood in its broadest
meaning; thus, it also covers, for example, embodiments
of di~erse thickness, such as sheets or membranes.
The shaped structures not only have outstanding resist-
ance to heat and resistance to chemicals but also have
superior mechanical properties, for example in respect of
the tensile streng~h, the abrasion resistance and the
modulus of elasticity. The solution of the aromatic
copolyamide can also be used in diverse ways, for example
for the production of fibers, ~heets, sheet-like ele-
ments, fibrous materials and other shaped articles.
The solvent used in the process for the preparation of
` the shaping solution of the aromatic copolyamide is
preferably a solvent of the amide type, in particular the
` solvents of the amide type which have been mentioned
further above, or a mixture of two or more of the said
; 20 compounds.
...
For the preparation of the shaping solution it is advant-
ageous if the conc~ntration of the aromatic copolyamide
is kept within a range between 4 and 15 % by weight, in
particular between 5 and 12 % by weiyht. If necessary,
the shaping solution can comprise an additi~e to promote
the solubility, it being possible to use at least one
metal halide of a metal of Groups I and II of the
Periodic ~able, for example lithium chloride, calcium
chloride or magnesium bromide, specifically in a concen-
tration of between 0.2 and 10 %, preferably of between0.5 and 5 ~, with respect to the total weight of the
shaping solution. The additive to promote the solubility
also promotes the stability of the shaping solution at
elevated temperature.
.
- 14 ~ ~
.
Shaping of the shaping solution to give a shaped article
can be carried out by any suitable dry process, wet
.` process or dry/wet process. In the cases in which a wet
process is used in order to shape the shaping solution,
for example to give filaments, the shaping solution or -
in this case - the spinning solution is extruded through
a die, for example a spinneret, into a coagulating
liquid. ~ith this procedure it is usually advantageous if
~ the coagulation liquid is composed of water or of an
; 10 aqueous solution containing a polar organic solvent. The
` polar organic solvent can be selected from thie same amide
solvents which are cus~omarily used for dissolving the
~ aromatic copolyamide.
,,.,~
The polar organic solvent used in the coagulation liquid
is preferably the same solvent as is contained in the
~` shaping solution. The coagulation liquid is preferably
used at a tempera~ure between 0C and the boiling point
: of the coagulation liquid under atmospheric pressure.
.,,
The polar organic solvent is preferably present in the
coagulation liquid in a concentration of less than 70 %
; by weight, in particular less than 50 ~ by weight.
.`~ The shaping process explained above is par~icularly;; suitable for the production of films or fibers from a
shaping solution.
..;
When producing fibers from the aromatic copolyamide, the
shaping or spinning solution is extruded through a
spinning head which has multiple spin orifices, the
;. filament-form streams of the ~pinning solution being
solidified in one of the coagulation liquids indicated
above (wet process) or in an atmosphere promoting evapor-
~; ation (dry process). A variant which is also suit~ble is
the "dry jiet/wet spinning process", as is described, for
example, in US-A-34 14 645. A conventional horiæontal or
vertical wet spinning machine, a dry jet wet spinning
,
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~ ~ '
,
machine or a spinning machine in which the ma erial flow
is downward under stress can be used for spinning.
In the case of wet spinning of an aromatic copolyamide
according to the invention, the coagulation is preferably
effected using a coagulation liquid containing an addi-
tive to promote coagulation, this coagulation being
followed by a further coagulation step, in the course of
which the coagulating filaments of the aromatic copoly-
amide are passed into a water bath which is kept a$ a
temperature of between 0 and 100C.
,.~
The additional coagulation step serves to complete the
coagulation by removal of the solvent. In addition,
additives to promote coagulation, if such substances are
used, are washed out of the coagulated filaments.
It is clear from the above description that the aromatic
copolyamide according to the invention can be processed
to give filaments without any problems, using conven-
tional spinning processes and equipment, without a
hazardous or harmful solvent, such as, for example,
~- 20 concentrated sulfuric acid, having to be used.
"~
Consequently, the risks for the operating personnel are
~ reduced. In addition, the filaments produced from the
; copolyamide according to the inYention have a dense
internal structure.
~..
The shaping solution can also be processed to give a film
using conventional fanning or extruding processes.
;~
Fibers or films which are produced by the shaping pro-
~ cesses indicated above are usually subjected to a
-~ stretching operation, by means of which not only the
mechanical properties, such as, for example, the tensile
strength and the modulus of elasticity, but also the
thermal properties, such as, for example, the stability
16 2~"~
:
to heat, of the filaments or films produced in this way
are improved.
Filaments composed of the aromatic copolyamides according
to the invention are as a rule stretched in order to
obtain a high mechanical strength and a high modulus of
elasticity. The stretching ratio is usually about 1:6 to
; 1:20. The stretching temperature is as a rule between 250
and 550C, preferably between 350 and 500C.
~Stretching can be carried out in a single step, in two
r~` 10 steps or in several steps and a hotplate or a cylindrical
heating device can be used for heating. In addition, the
;stretched filaments or films can be subjected to a
, further heat treatment at the same temperature or a
higher temperature in order to Lmprove the crystalline
structure. In this context it is pointed out that the
`~aromatic copolyamide according to the invention is not
only surprisingly advantageous with respect to its
`solubility in conventional organic solvents but can also
: be stretched under "mild" operating conditions without
any problems after the production of the fibers or films.
;The fibers obtainable from the copolymers according to
;the invention are distinguished by high tear strengths
and initial moduli and by low elongations at break.
:,
A further preferred subject of the pre~ent invention
comprises fibers composed of the copolymers according to
the invention, which have a tear strength of about 90 to
250 cN/tex, in particular 150 to 250 cN/tex, an initial
modulus, with respect to 100 ~ elongation, of about 25 ~o
60 N/tex, in particular 35 to 50 N/tex, and an elongation
at break of about 3 to 7 ~, in particular 4 to 6 %.
It has been found, surprisingly, that fibers which have
high transverse strength values not obtained hitherto for
aramides and which have a combination of exceptionally
~,,
.
. : ,
- 17 - 2~
high tear strength and transverse strength can be
produced from the copolyamides according to the invention
; by using particular stretching conditions~ The loop
; strength (in accordance with DIN 53843) or the knot
strength (in accordance with DIN 53842 Part 1~ can be
used as a criterion for the transverse strengths.
Preferred fibers composed of the copolyamides according
to the invention have knot strengths of 25 to 80 cN/tex,
in particular of 50 to 80 cN/tex, and/or loop ~tren~ths
of 40 to 130 cN/tex, in particular of 85 to 120 cN/tex.
.;, .
i Very particularly preferred fibers composed of the
copolyamides according to the invention have tear
strengths of more than 200 cN/tex, in particular of 200
to 250 cN/tex, and loop s~rengths of more than 80 cN/tex,
in particular of 85 to 120 cN/tex.
These particularly preferred fibers are obtainable by
~ stretching the spun fibers at elevated temperature and
;~ using a spin finish preparation which is stable under the
stretching conditions. Such preparations essentially
;~ 20 contain a particulate, inert inorganic material which
lowers the sliding friction between the fibers during the
stretching process. These preparations are usually
applied to the fibers from an aqueous suspension and a
;uniform layer of said incrganic mat0rial is ~hen produced
around the fibers by drying. Examples of suitable
inorganic and inert particles are graphite, talc,
colloidal silica, water-repellent silica, mica, hydrated
magnesium silicate or aqueous dispersions containing
magnesium ~ilicate and an aqueous gel-forming inorganic
compound, such as aluminum silicate.
Examples of such preparations are describPd in
JP-A-60-239,522, JP-A-60-239,523 and EP-A-121,132.
'
~3~
Stretching of the aramid fibers pretreated in this way
is generally carried out at fiber temperatures of higher
than 300C, pre~erably at 350 to 550C. The degrees of
stretching for the production of these particularly
preferred aramide fibers are usually 1:8 to 1:20, prefer-
ably 1:9 to 1:15.
The invention also relates to such fibers and a process
for their production.
The fibers composed of an aromatic copolyamide according
to the invention, which have outstanding m~chanical and
; thermal properties and are distinguished by a high
stretchability, can be used industrially in very diverse
ways, for example for reinforcing plastics, in particular
as reinforcing materials for the fabric inserts in car
tires and other rubber articles, as heat-resistant
insulating materials, for the production of filter
fabrics and as lightweight insulating materials. Films
composed of an aromatic copolyamide according to the
invention can be used as heat-resistant electrical
insulating materials, in particular for ~he production of
membranes, for example as support material for separation
membranes.
Further features and advantages of the inven~ion are
explained in more detail below with the aid of examples.
Howev~r, it is to be understood that the invention is not
restricted to the illustrative examples. On the contrary,
numerous possibilities for modifications and/or supple-
ments are available to a person skilled in the art,
taking the illustrative examples as a basis, without
having to go beyond the basic concept of the invention.
-19~ 2~3~
Example 1
"
Aromatic copolyamide obtained from 100 mol % of tereph-
thalic acid dichloride, 50 mol ~ of p-phenylenediamine,
25 mol % of 1,4-bis-(4-aminophenoxy)-benzene and 25 mol %
~;.5 of 3,4'-diaminodiphenyl ether.
;,
162.2 g (1.5 mol) of p-phenylenediamine, lS0.2 g
(O.75 mol) of 3,4~-diaminodiphenyl ether and 219.3 g
(O.75 mol) of 1,4-bis-(4-aminophenoxy)-benzene are
.dissolved, under nitrogen, in 14042 g of N-methylpyr-
rolidone and 607.3 g (3 mols) of terephthalic acid
dichloride are added in the course of 20 minutes at
between 35C and 55C. When ~he desired viscosity (~
= 5.5 dl/g) is obtained, the polycondensation reaction is
stopped by adding 4.7 g of acetyl chloride and the
;~15 reaction mixture is then neutralized with 328.2 g of
calcium oxide (55 % strength suspension in NMP). The
solution is stirred further at 120C. Th~ solution is
filtered, degassed and spun wet. To this end, it is spun
at a rate of 16 m/min from a die which has 100 orifices
each 0.1 mm in diameter into a coagulation bath compris-
ing a 35 % solution of N-methylpyrrolidone in water,
.;which is at 80C. The resulting filaments are stretched
to 11 times their length through two water baths, a
washing machine, via a drying godet and finally over a
hot plate at temperatures of 400 to 440C.
. . .
The filament linear density is 1.91 dtex for a tear strength of
190 cN/tex, an elongation of 4 ~ and an initial modulus
of 41 N/tex, with respect to 100 % elongation.
Examples 2 to 37
Further aromatic copolyamides are produced, spun and
tested in accordance with the procedure described in
Example 1. The diamines used, the proportions thereof,
the solution viscosities of the resulting polymers, the
.
- 20 ~
spinning conditions and properties of the resulting
fibers are given in Table 1 ~elow. The following abbrevi-
ations are used for the monomers in Table 1:
TPC = terephthalic acid dichloride
IPC = isophthalic acid dichloride
:`NDC = 2,6-naphthalenedicarboxylic acid dichloride
PPD = p-phenylenediamine
3,4'-DADPE = 3,4'-diaminodiphenyl ether
BAPOB = 1,4-bis-(4-aminophenoxy)-benzene
~,~10 4, 4 ' -DABA = 4,4'-diaminobenzanilide
. Cl-PPD = chloro-para-phenylenediamine
MPD = m-phenylenediamine
DM~ = 3,5'-dLmethylbenzidine
.; .
. .
:'
:
.~.
.:~
. ~ .....
: ,
~ - 21 ~
.' ~ . . ,..................... _...... .. I
Example No. 2 3 4 5 6 7 ¦ 8 9
. TPC (mol %) 100 100 100 100 100 100 100 100.~ S
IPC (mol %) 0 0 0 0 0 0 0 0
NDC (mol %) 0 0 0 . 0 0 0 0 0
~' _ _ _
: 10 PPD (mol ~) 55 50 50 50 50 50 50 50
3,4'-DADPE (mol ~) 22.5 20 40 30 20 30 20 25
_ _
BAPOB (mol %) 22.5 30 10 20 20 10 20 25
.
4,4'-DABA (mol %) O O O O O O 10 O
Cl-PPD (mol %) 0 0 0 0 10 10 0 0
Spinning solution 6 6 6 6 6 6 6 6
concentratlon ( % ~ _
Inherent viscosity 6.2 6.5 6.3 4.6 6.5 5.8 6.0 5.9
(dl/g) in NMP
0.25 % strength
at 25~C
.
~ Strength (cN/tex) 143 134 184 160 124 170 163 190
, _ . _ _
30 Elongation (%) 3.4 3.8 3.5 3.4 3~0 3.3 3.7 4.0
. __ ~ . , . _ _
. Modulus (N/tex) 41 34 50 44 41 52 41 41
_ _ ._
Stretching 1: 8 9 10 15 14 10 14 14
3~ _ _ ~ _ _ _ _ _ _ _
22 2 ~
. _ _ _ _ 10 11 12 13 ~4 15 16 l7
':. _ _
TPC (mol %) 100 100100 100 100 100 100 100
"~ 5 _
IPC (mol %) 0 0 0 0 0 0 0 0
: NDC (mol %) 0 0 0 0 0 0 0 0
PPD (mol %) 50 60 50 50 45 40 45 45
3,4'-DADPE (mol %) 17.5 10 45 35 40 50 45 50
B~POB (mol %~ 17.5 30 5 15 15 10 10 _
4,4'-DABA (mol %) 15 O 0 0 0 0 0 O
Cl-PPD (mol %) 0 0 0 0 0 0 0 0
: 20 Spinning solution 6 6 10 8 10 10 6 12
concentration (~) _
Inherent viscosity 6.4 6.1 4.5 4.6 3.6 3.8 6.1 6.3
. (dl/g) in NMP
at 25C
,''~ .
Strength (cN/tex) 16498 203 197 la3 lB4 165 17
;~ 30 Elongation (%) 3.3 4.33.8 3.7 3.5 3.5 3.4 3.
_ _ . . .. _ _
. Modulus (N/~ex)45 27 52 48 52 50 4B 55
.: Stretching 1: 7 4 14 12 11 18 9 13
:, 35 ~ ~ _ ~ _ _ _ ~ _
:
.
.
,' ' ~
; - 23 - 2~
. ~ le Ro. 19 19 20 21 22 23 2425
_
TPC (mol %) I00 B0 85 85 80 80 75100
IPC (mol %) 0 20 15 15 10 10 10 0
NDC (mol %) 0 0 0 0 10 10 15 0
PPD (mol %) 50 60 60 60 60 65 6040
3, 4 ' -DADPE (mol % ~22 . 5 10 10 15 15 10 1055
. . _ _ _
BAPOB (mol %~ 22.5 30 30 25 25 25 30 5
. _ _
4, 4 ' -DABA (mol % ) 5 0 0 0 0 0 0 O
Cl-PPD (mol % ) 0 0 0 __ 0 0 0
Spinning solution 6 6 6 6 8 6 6 12
concentration (%) _ _ _
Inherent viscosity 7 . 0 6 .1 6 .1 5.6 5.4 5.8 6 .1 6 . 3
(dl/g) in NMP
0.25 % strength
at 25C _ _ _ _
Strength (cN/tex) 169 99 94 94 96 94 95 182
Elong~tion (%) 3.8 4.8 4.3 4.2 3.9 3.B 4.3 3.~
. . _ . _
Modulus (N~tex) 40 24 27 29 30 29 27 55
~ c~lr~ 1~ 15 5 4.5 4.5 4 6 5.3 4 2 l8
3 1 ~ ~
~ - 24 -
_ __ , . ___ , . _ , , _
Example No. 26 27 28 29 30 31 32 3~
_ _ _
TPC (mol ~) 100 100100 100 100 100 100 100
_ _
IPC ~mol %) 0 0 0 0 0 0 0 0
._ . ........ ~ _ _ .
. NDC (mol %) 0 0 0 0 0 0 0 0
_ _ _
PPD (mol %) 50 50 45 45 45 50 45 45
3,4'-DADPE (mol %) 35 35 50 35 30 30 30 30
.' . . .
BAPOB (mol %) 15 15 5 15 15 10 10 5
_
4,4'-DABA (mol %) 0 0 0 0 0 0 0 O
. _
MPD (mol %) O O O 5 10 10 15 20
. . _ _
Spinning solution 6 8 10 6 6 6 6 6
concentration (%)
: . _ _
: Inherent viscosity 6.8 5.01 4 5 . 4 4.8 4.5 5 5.1
(dl/g) in NMP
. _ _
Strength (cN/tex) 248 223 203 210 188 202 160 170
_ _
~ Elongation (%) S 4.4 3.8 5 5.4 5.6 5 5.2
. _ __
~ 30 Modulus (N/tex) 50 48 52 42 36 38 35 36
.
; Stretching 1: 12 ~ 1 D 9 5 8 7 10 10
Loop strength 114 85 87 84 42
(cN/tex)
~not strength 69 59 53 63 27
(cN/tex) l _ ~ _ _ _
2 ~
- 25 -
__ ........ _ . . ..
~; Example No. 34 35 36 37
~ ... _
TPC (mol %) 100 100 100 100
IPC (mol %) 0 0 0 0
NDC ~mol %) 0 0 0 0
. _
PPD (mol %) 45 35 40 45
3,4'-DADPE (mol %)30 30 25 25
_ .
.~ BAPOB (mol %) 10 10 5 5
4,4'-DABA (mol %) 0 5 5 0
, _ ._ . .__
.~ MPD (mol %) O S O
DMB (mol %) 20 20 20 25
.' .
. Spinning solution 6 6 6 6
concentration (%)
.
Inherent viscosity 6.32 6.10 6.30 6.33
(dl/g) in NMP
, .
Strength IcN/tex)189 174 198 146
_ -................ _
Elongation (%) 3.5 3.2 3.6 2.5
.
: Modulus (N/tex) 59 60 b0 67
.
Stretching 1: 7 11 10 7
_ __ __ __ __ __ _____________________________
