FR2685001A1 - Water-soluble and/or water-dispersible polyamides, preparation and use of these polyamides - Google Patents

Abstract

New water-soluble and/or water-dispersible polyamides, their preparation and their use for the sizing of textile yarns. The invention relates first of all to new water-soluble and/or water-dispersible copolyamides characterised in that they contain at least: - aromatic dicarbonyl and/or aliphatic dicarbonyl units, - sulphoaryldicarbonyl units, - oxyalkylenediamine units, by themselves or with aliphatic diamine units, and in that they have a number-average molecular mass of between 2000 and 30,000. These water-soluble and/or water-dispersible copolyamides can be prepared by reaction of one or a number of aromatic and/or aliphatic dicarboxylic acids, sulphoaryldicarboxylic acids, one or a number of aliphatic diamines and one or a number of oxyalkylenediamines.

Description

HYDROSOLUBLE AND / OR HYDRODISPERSABLE POLYAMIDES,
PREPARATION AND USE OF THESE POLYAMIDES
The present invention relates to new water-soluble and / or water-dispersible polyamides, their preparation and their use for sizing textile threads.

 In the present text, the term son covers both monofilaments, assemblies of long unitary filaments or yarns of staple fibers.

 Some water-soluble polyamides have been described in the prior art.

 Thus, US Pat. No. 3,108,991 describes water-soluble linear polyamides in the formula of which alkylphosphorus groups are inserted. The presence of repeating phosphorus units, constituting about half of the molecule, leads to a high cost and access to the phosphorus monomer is not very easy. In addition, these compounds are not readily soluble in water.

 GB-A-1,463,106 discloses water-soluble polyamides having aliphatic dicarboxylic acid units and aliphatic diamine units of which at least 95 mol% are derived from a polyoxyalkylene diamine having 3 to 14 ether bridges. In fact, the compounds obtained swell, but are not dissolved in water.

 JP-A-75-092996 discloses water-soluble copolyamides of which a portion of the dicarboxylic acid units is derived from a sulfonated aromatic carboxylic acid. The hydrophilicity of the molecule is not optimized, which results in slow dissolution and insufficient affinity for certain substrates such as son or films.

The present invention relates first of all to new water-soluble and / or water-dispersible copolyamides, characterized in that they comprise at least
aromatic dicarbonyl and / or dicarbonyl units
aliphatic,
sulfo-aryldicarbonyl units,
oxyalkylenediamine units, alone or with
aliphatic diamine units, and in that they have a number average molar mass of between 2000 and 30 000.

In the present text, it is considered in the polymeric sequence of water-soluble and / or water-dispersible copolyamides that the different units are represented as follows
aromatic dicarbonyl units (= residue from a phenyldicarboxylic acid)
-OC - Ar -CO ---
Ar representing a phenylene radical, optionally comprising
one or more substituents such as alkyl radical having 1 to 4
carbon atoms, halogen atom or OH radical, or a
combination of several ortho- or peri-condensed phenyl radicals
or more phenyl radicals linked together by groups
inerts such as simple valency bond, alkylene radical, group
ether, ketone group or sulphone group
- aliphatic dicarbonyl units (= residue from an acid
aliphatic dicarboxylic) - OC - R 1 - CO--
R 1 preferably represents an alkylene radical, linear or
branched, having 4 to 10 carbon atoms
sulfo-aryldicarbonyl units (= residue from a sul-fo-aryldicarboxylic acid)

M representing a hydrogen, sodium, lithium or potassium atom and Q representing a phenylene radical or a combination of several ortho- or peri-condensed phenyl radicals
or more phenyl radicals linked together by groups
inerts such as simple valency bond, alkylene radical, group
ether, ketone group or sulphone group
- diamine aliphatic units (= residue from a diamine
aliphatic)
-HN - R2 - NH
R2 preferably representing an alkylene radical, linear or
branched, having 4 to 10 carbon atoms, a radical
aryl-dialkylene in which the alkylene radicals, linear or
branched have from 1 to 10 carbon atoms and the part
aromatic is constituted by a phenylene radical
substituted
- oxyalkylene-diamine units (= residue from an oxyalkylene

<tb> diamine)
<tb><SEP> -HN <SEP> - <SEP> - <SEP> CH2 <SEP> - <SEP> CH <SEP> - <SEP> 0 <SEP> - <SEP> CH2 <SEP> - <SEP > CH <SEP> - <SEP> NH <SEP>
<tb><SEP> R3 <SEP> n <SEP> R3
<Tb>
R3 representing a hydrogen atom or a methyl radical and n
representing a number from 1 to 150.

 Among the aromatic dicarbonyl units, mention may be made of the isophthaloyl, terephthaloyl, orthophthaloyl, naphthalene1,2-dicarbonyl, naphthalene-1,4-dicarbonyl, naphthalene-1,5-dicarbonyl, naphthalene-1,6-dicarbonyl and naphthalene-1 units. , 7-dicarbonyl, naphthalene-1,8-dicarbonyl, naphthalene-2,3-dicarbonyl, naphthalene-2,6-dicarbonyl, naphthalene-2,7-dicarbonyl, 1,1,3-trimethyl-3-phenylindan 4 ', 5 -dicarbonyle.

 Among the aliphatic dicarbonyl units, mention may be made, for example, of the succinoyl, glutaroyl, 2-methylsuccinoyl, 2-methylglutaroyl, adipoyl, suberyl, azeloyl and sebacoyl moieties.

 The water-soluble and / or water-dispersible copolyamides of the invention preferably comprise adipoyl and / or isophthaloyl units.

 Among the sulfo-aryldicarbonyl units, mention may be made, for example, of the sulpho-terephthaloyl, sulphoisophthaloyl, sulpho-orthophthaloyl, trisulphonaphthalene-2,7-dicarbonyl, sulphodiphenylsulphone-4,4'-dicarbonyl, sulphodiphenyl-dicarbonyl and sulphodiphenylmethane units. 4,4'-dicarbonyl, sulfo-5-phenoxyisophthaloyl, whose sulphonic acid function is free or is preferably salified by a sodium, potassium or lithium atom.

 The water-soluble and / or water-dispersible copolyamides of the invention preferably comprise sodio-5-oxysulphonylisophthaloyl units.

 Among the aliphatic diamine units, mention may be made, for example, of the tetramethylenediamine, 2-methyl-tetramethylenediamine, pentamethylenediamine, 2-methylpentamethylenediamine, 3-methylpentamethylenediamine and 2-ethyl-tetramethylenediamine units. hexamethylenediamine, decamethylenediamine.

 The water-soluble and / or water-dispersible copolyamides of the invention preferably comprise hexamethylenediamine units.

 Among the oxyalkylenediamine units, mention may be made, for example, of 3-oxa-pentamethylenediamine, 3,6-dioxa-octamethylenediamine, 3,6,9-trioxa-undecamethylenediamine, 3,6,9, 12-tétraoxatétradécaméthylène diamine.

 it is naturally possible to have several different units of the same type in the formula of the water-soluble and / or water-dispersible copolyamides, for example aromatic and aliphatic dicarbonyl units from different aromatic and / or aliphatic diacids, aliphatic diamine units from different diamines .

 In the formula of water-soluble and / or water-dispersible copolyamides, the molar percentage of sulfo-aryldicarbonyl units with respect to all the units derived from dicarboxylic acids is generally between 8% and 25% and preferably between 12% and 18%, the complement consisting of aromatic and / or aliphatic dicarbonyl units.

 The molar percentage of the oxyalkylenediamine units relative to all the units derived from diamines is generally between 10% and 100% and preferably between 50% and 90%, the balance being constituted by aliphatic diamine units.

 Generally, the water-soluble and / or water-dispersible copolyamides of the invention have a glass transition temperature (Tg C) at 85% relative humidity (RH) between -50c and + 1000C.

 Often, a double glass transition temperature is observed: a first located in a zone of -50 ° C to + 10 ° C and a second located in a zone of + 10C to + 1000C.

 The copolyamides of the invention may also have only one Tg C, in particular when the molar proportion of the oxyalkylenediamine units predominates among all the diamine units.

 The water-soluble and / or water-dispersible copolyamides may be prepared by reaction of one or more aromatic and / or aliphatic dicarboxylic acids, sulfo-aryldicarboxylic acids, of one or more aliphatic diamines and of one or more oxyalkylenediamines, defined above.

 It is also possible to use lactams such as caprolactam or, for a portion of the reagents, polyamides such as nylon-6,6, nylon-6 or nylon-11, in combination with all or some of the monomers indicated above. .

 The preparation of the water-soluble and / or water-dispersible copolyamides comprises a first step which corresponds schematically to the salification of the carboxylic functions of the various acidic monomers by the amine functional groups of the various amine monomers.

 The amounts of dicarboxylic monomers and of diamine monomers (as well as the amounts of lactams or polyamides which can also be used) are not necessarily stoichiometric during the salification. It is possible to use an excess of carboxylic functions or an excess of amine functions and subsequently readjust the ratios of the monomers to obtain an overall ratio of carboxylic functions / amine functional groups that are substantially stoichiometric.

 This first step is generally performed without heating. However, since the salification reaction is exothermic, the temperature is generally between 20 and 100 ° C., without these values being critical.

 For convenience, this salification is usually carried out in solution in water. The concentration of the different monomers is not critical. In practice, it is generally between 20% and 80% by weight per total weight of the reaction mixture.

 This step is relatively fast. The reaction mixture is then heated to remove at least a portion of the water that may be present.

 Then, the temperature is raised under autogenous pressure, generally between 100 ° C. and 300 ° C., in order to carry out the second step, which corresponds to the polyamidification.

 During this polyamidification step, the water that still remains possibly in the reaction medium and the water formed by the polyamidification reaction itself are distilled.

 Optionally, a catalyst can be used to promote the polyamidification reaction, such as, for example, hypophosphorous acid, phenylphosphinic acid, phenylphosphonic acid or tris (nonylphenyl) phosphite.

 The catalyst may represent from 0% to 1% by weight relative to the total weight of the various monomers.

 This distillation of the water can be completed at the end of the polyamidification reaction by reducing the super-atmospheric pressure at atmospheric pressure and then at a pressure below atmospheric pressure.

 Thus, the pressure in the reactor can reach 2 MPa (20 bar) and preferably be between 0.3 MPa (3 bar) and 1 MPa (10 bar) during the polyamidification reaction, then it can be reduced to possibly a few Pa if it is desired to remove the last traces of water copolyamide.

 The duration of the polyamidification step is very variable.

Generally it is between a few minutes and several hours.

 This variant of the process for the preparation of water-soluble and / or water-dispersible copolyamides, in which only the water can be used as a solvent for the initial salification reaction, is called the bulk preparation process.

 It is also possible to operate in an organic solvent: such a variant will be called a solution preparation process.

 As solvents which may be used in this variant, mention may be made of 1,3-dimethyl-imidazolidinone-2 (or dimethylethylene-urea), 1,3-dimethyl-3,4,5,6-tetrahydro-2 ( 1H) -pyrimidinone (or dimethylpropylene-urea), N-methylpyrrolidone and dimethylacetamide.

 The water-soluble and / or water-dispersible copolyamides of the invention are particularly suitable for gluing yarns.

 They have excellent activity, far superior to that of conventional products currently used, such as polyacrylic acids.

 They make it possible to obtain better returns, especially on high-speed trades and more particularly on air-jet looms and water-jet looms. Currently conventional gluing products can not be used on water jet looms.

 They lead to an excellent compromise between two unacceptable defects which are, on the one hand, the "blocking" (or bonding on beams) during the assembly of the primary beams or the course of the coil of the beam on the trade and, d on the other hand, the fouling of the looms by dusting (phenomenon representative of an abrasion).

 The invention therefore also relates to the use, for the sizing of textile yarn chains, of aqueous compositions containing from 1% to 50% by weight of water-soluble and / or water-dispersible copolyamides described above with respect to the total weight of the composition and preferably from 5% to 30%.

 This use consists in applying the water-soluble and / or water-dispersible copolyamides to the yarns, by immersing said yarns in an aqueous bath containing the copolyamides at the desired concentration and temperature, then spinning by passing said yarns between rolls and finally drying the yarns. thus glued in hot rooms: the chain of threads is then ready to be woven.

 Among the conventional methods of sizing for continuous yarn (filament yarn or continuous filament yarn), there may be mentioned for example the sizing in sectional (European system), the conventional sizing (classic system or English system) and the sizing in primary tablecloth (single end sizing or Japanese system).

 The copolyamides of the invention are of particular interest for priming synthetic yarns (filaments yarns) of polyamides, but can also be used for fibers (spun yarns) of polyamides, optionally mixed with natural fibers, for natural fibers such as cotton by for example, for artificial or synthetic fibers, for glass fibers or for other yarns such as synthetic yarns such as acrylics, polyesters, polyimides, chlorofibres, polyethylene, polypropylene, aramids and their copolymers or artificial yarns such as acetates , tri acetate, viscose.

 In addition, they allow to glue any type of son, whether textured or not, twisted or not and according to any sizing technique, whether of sectional sizing, conventional , in primary sheet or other.

 A very important advantage of these products is that they withstand the performance constraints of new looms.

They allow to glue and weave at high speed.

In addition, they are easily removable with water.

 The following examples illustrate the invention.

Example 1 - Polymer A
The synthesis is carried out in aqueous medium from diacids and diamines. The process involves a first salification step followed by a polycondensation step.

salification
In a 10-liter glass flask purged with nitrogen, 721 g of adipic acid (4.93 mol), 819 g of isophthalic acid (4.93 mol) and 293.9 g 5-sodiooxysulfonylisophthalic acid (1.096 mol).

 1810 g of water are then introduced: the suspension is stirred; 267.6 g of methylpentamethylenediamine (2.3 mol), 1298.7 g of 3,6-dioxa-octamethylene-1,8-diamine (8.77 mol) and 3 g of hypophosphorous acid are then added to the previous suspension. The medium is still stirring.

 The salification reaction is exothermic.

 453 g of water are used to rinse the material used for the introduction of the reagents; this rinsing water is added to the salification medium. The final concentration of the salt formed in the water is 60% by weight by weight (w / w).

Pol vamidification
The salt solution is introduced into a 7.5 liter stainless steel reactor equipped with a stirrer, a jacket for the circulation of the coolant and a distillation column controlled by a solenoid valve.

 The medium is then purged four times in succession with nitrogen.

A first step, called evaporation, is performed at atmospheric pressure to reduce the concentration of salt to 70% w / w.

Evaporation is conducted for 30 minutes from 106 to 112 ° C in the reaction mixture (mass).

 The control valves are then closed and the temperature increases from 112ex to 1770C in the mass in 45 minutes. The pressure in the reactor then reaches 0.7 MPa (7 bar).

 At this pressure, the water distillation starts in parallel, the temperature in the mass is increased from 177 C to 228C. This phase lasts about 120 minutes and allows to extract 83% of the water.

 A decompression phase is then initiated and allows to go from 0.7 MPa to atmospheric pressure in 1 hour and from 230 C mass to 261 C mass. A vacuum phase then brings the reactor pressure to 200 Pa in 50 minutes. The temperature in the mass is maintained at 267 C.

 Finally, the pressure of 200 Pa and the temperature of 267 C are maintained during a polycondensation phase lasting 30 minutes. After reducing the internal pressure to 0.1 MPa through a nitrogen overpressure, an orange-yellow polymer is poured through the bottom valve of the reactor vessel.

Polymer A is then analyzed
solubility in water at 30% and 10% w / w
viscosity index measured in metacresol at 25C for
a weight / weight concentration of 0.5%
- thermal analysis (Tg0C)
- analysis of terminal groups.

 The results are summarized in Table 1.

Example No. 2 - Polymer B
In this example, the methylpentamethylenediamine is substituted with hexamethylenediamine. The process according to Example 1 is repeated to obtain the polymer B.

The quantities of reagents used are as follows
Adipic acid: 721 g (4.93 mol)
Isophthalic acid: 820 g (4.93 mol)
5-Sodio-oxysulfonyl-isophthalic acid: 249 g (0.929 mol)
Hexamethylenediamine: 271 g (2.33 mol)
3,6-dioxa-octamethylene-1,8-diamine: 1301 g (8.775 mol)
The analytical results are summarized in Table No. 1.

Example No. 3 - Polymer C
In this example, the amount of 3,6-dioxa-octamethylene-1,8-diamine is greatly reduced and the amount of 5-sodio-oxysulfonyl-isophthalic acid is increased.

The quantities of reagents used are as follows
Adipic acid: 681 g (4,662 mol)
Isophthalic acid: 774 g (4,662 mol)
5-Sodio-oxysulfonyl-isophthalic acid: 441 g (1.645 mol)
Hexamethylenediamine: 956 g (8.229 mol)
3,6-dioxa-octamethylene-1,8-diamine: 406 g (2,742 mol)
The analytical results are summarized in Table No. 1.

Comparative Test No. 1 - Polymer D
In this comparative test, 5-sodiooxysulfonyl-isophthalic acid is removed.

The quantities of reagents used are as follows
Adipic acid: 801.5 g (5.48 mol)
Isophthalic acid: 910 g (5.48 mol)
Methylpentamethylenediamine: 270 g (2.31 mol)
3,6-dioxa-octamethylene-1,8-diamine: 1301 g (8.775 mol)
The analytical results are summarized in Table No. 1.

 It is noted that the copolyamide obtained is not soluble in water and therefore can not be used for sizing textile threads.

Anal anal techniaues
1 / Determination of the glass transition temperature
A collodion with 30% of polymer in water is first made and then cast on a glass plate so as to obtain a film of a few millimeters thick after evaporation of the water.

The determination of the glass transition temperature is carried out using a SETARAM CS 92 DSC apparatus. In order to be able to compare the products, the films are first conditioned for 8 days at 20 ° C. at 85% RH. The thermal analysis is then performed according to the temperature profile following 100C / min

 An aluminum capsule filled with 15 mg of polymer (film-shaped) is used for the measurement.

2 / Determination of the viscosity number
A solution of low C concentration and about exactly 0.5% is made in metacresol. The passage time through a capillary (diameter 1.3 mm) is measured for the solvent (To) and for the solution (T). The viscosity index is given by the formula

3 / Determination of terminal gangs (GT3
The method corresponds to a potentiometric determination by hydrochloric acid in trifluoroethanol medium of amine and carboxylate functions (formed after addition of tetrabutylammonium hydroxide).

 Terminal groupings are given in milliequivalents / kilogram (meq / kg).

They make it possible to calculate the average molar mass in number from the following formula
2 x 10-6
Mn =
number of GTs

% <SEP> molar <SEP> of <SEP> units <SEP> in <SEP><SEP> copolyamide <SEP> Index <SEP> Mn <SEP> Soluble <SEP> Tg C
<tb> Copolyamide <SEP> of <SEP> calculated <SEP> to <SEP> 10 <SEP>%
<tb> AA <SEP> AI <SEP> AISNa <SEP> HMD <SEP> MPMD <SEP> DOMD <SEP> Viscosity <SEP> to <SEP> 30 <SEP>% <SEP> to <SEP> 85 <SEP >% <SEP> HR
<tb> yes
<tb> Polymer <SEP> A <SEP> 22.4 <SEP> 22.4 <SEP> 5.0 <SEP> 0 <SEP> 10.4 <SEP> 39.8 <SEP> 43 <SEP> 6300 <SEP> yes <SEP> - <SEP> 32
<tb> yes
<tb> Polymer <SEP> B <SEP> 22.5 <SEP> 22.5 <SEP> 4.25 <SEP> 10.65 <SEP> 0 <SEP> 40.1 <SEP> 29 <SEP> 5800 <SEP> yes <SEP> - <SEP> 35
<tb> yes <SEP> - <SEP> 15
<tb> Polymer <SEP> C <SEP> 21.25 <SEP> 21.25 <SEP> 7.5 <SEP> 37.5 <SEP> 0 <SEP> 12.5 <SEP> 55 <SEP> 7800 <SEP> yes <SEP> + <SEP> 45
<tb> - <SEP> 32
<tb> Polymer <SEP> D <SEP> 24.85 <SEP> 24.85 <SEP> 0 <SEP> 0 <SEP> 10.5 <SEP> 39.8 <SEP> 86 <SEP> 15000 <SEP > insoluble <SEP> + <SEP> 73
<tb> AA = adipoyl
AI = isophthaloyl
AISNa = 5-sodio-oxysulfonyl-isophthaloyl
HMD = hexamethylene diamine
MPMD = methylpentamethylene diamine
DOMD = 3,6-dioxa-octamethylene-1,8-diamine
TABLE N 1
EXAMPLE No. 4 and Comparative Test No. 2
Gluing tests
Sizing tests were carried out using aqueous solutions, on the one hand of the polymer B prepared in Example 2 and, on the other hand, a commercial polyacrylic acid having the following characteristics:
number molecular weight (Mn): about 20,000
molecular weight (Mw): about 100,000
polydispersity index: about 5
- Glass transition temperature at 65% RH: 1300C.

 These solutions, constituting the baths of glue, were prepared in the following way: each of the 2 polymers is dissolved at 20% in demineralized water.

 The sizing operation is carried out using a SUCKER laboratory machine (marketed by SUCKER) adapted to operate in a "primary web" system, on a polyamide chain 6.6, 78 decitex, 68 strands, no twisted, the speed of passage on the gluing machine being 100 m / min; the settings are optimized to deposit on the wire about 5% by weight of dry polymer relative to the mass of the wire.

 The principle of the operation is as follows: the polyamide chain is immersed in the bath of glue or sprayed by the bath of glue, then dried by passage in heated chambers at 1300C, then on cylinders heated to decreasing temperatures of 125 to 900C; a lubricant (wax melted at 90 ° C) can be applied to the wire at a rate of 0.3% with respect to the weight of the wire, at the outlet of the drying cylinders.After cooling in a ventilated cooling chamber, the wires are wound on the primary beams they are then combined to make a beam for the loom.

The effectiveness of the products tested is evaluated before joining the primary beams, using the device "SHIRLEY FILAMENT
COUNTER "of the SHIRLEY INSTITUTE of Manchester according to the method published at the 7th Symposium of Textile Gluing of Mulhouse of October 15, 16 and 17, 1986.

 This test consists in measuring the ability of a polymer to bond together the single strands forming the wire.

 During the measurement the device records and counts the vibrations emitted during the cutting of the individualized elements consisting of a unitary strand or several glued strands.

The cohesion index C is expressed by the relation
C = 100 (n - x) / (n - 1) where n represents the number of unit strands constituting the wire
x the number of individualized elements counted.

 In the absence of glue, all single strands are independent; x is then equal to n and C = 0.

 The cohesion is maximum when all the unitary strands are linked; x is then equal to 1 and C = 100.

 The cohesion index is measured before and after work on a WEBTESTER usometer of the Textile Institute of Reutligen (measured after 50, 150 and 300 cycles).

 This device simulates the work done by the yarn during the weaving operation.

Table 2 below indicates the cohesion index of the yarn after 50, 150 and 300 cycles.

<tb><SEP> Index <SEP> of <SEP> cohesion <SEP> C <SEP> in <SEP> function
<tb><SEP> Testing <SEP> Polymer <SEP> of <SEP> Number <SEP> of <SEP> Cycles
<tb><SEP> used
<tb><SEP> 0 <SEP> cycle <SEP> 50 <SEP> cycles <SEP> 150 <SEP> cycles <SEP> 300 <SEP> cycles
<tb> Example <SEP> 4 <SEP> B <SEP> 75 <SEP> 65 <SEP> 55 <SEP> 30
<tb><SEP><SEP> acid test
<tb> comparative <SEP> poly- <SEP> 65 <SEP> 40 <SEP> 20 <SEP> 15
<tb><SEP> n <SEP> e <SEP> 2 <SEP> acrylic
<Tb>

TABLE N- 2
It is observed that a better sizing is obtained from the beginning with the copolyamides of the invention and that the cohesion index, obtained with these copolyamides, decreases significantly less, depending on the work underwent, than that obtained with the polyacryl acids. usually used.

Claims (23)

 1 - water-soluble and / or water-dispersible copolyamides, characterized in that they comprise at least  aromatic dicarbonyl and / or dicarbonyl units  aliphatic,  sulfo-aryldicarbonyl units,  oxyalkylenediamine units, alone or with  aliphatic diamine units, and in that they have a number average molar mass of between 2000 and 30 000.  2 - Copolyamides according to claim 1, characterized in that the patterns they comprise are represented as follows:  aromatic dicarbonyl units (= residue from a phenyidicarboxylic acid)  - OC - Ar - CO-  Ar representing a phenylene radical, optionally comprising  one or more substituents such as alkyl radical having 1 to 4  carbon atoms, halogen atom or OH radical, or a  combination of several ortho- or peri-condensed phenyl radicals  or more phenyl radicals linked together by groups  inerts such as simple valency bond, alkylene radical, group  ether, ketone group or sulphone group  - aliphatic dicarbonyl units (= residue from an acid  aliphatic dicarboxylic acid) -OC - RI - CO -  R 1 preferably represents an alkylene radical, linear or  branched, having 4 to 10 carbon atoms - sulfo-aryldicarbonyl units (= residue from sulfo-aryldicarboxylic acid)

 substituted - oxyalkylene-diamine units (= residue from an oxyalkylene  aromatic is constituted by a phenylene radical  branched have from 1 to 10 carbon atoms and the part  aryl-dialkylene in which the alkylene radicals, linear or  branched, having 4 to 10 carbon atoms, a radical  R2 preferably representing an alkylene radical, linear or  - HN - R2 -NH  aliphatic)  ether, ketone group or sulfone group - diamine aliphatic units (= residue from a diamine  inerts such as simple valency bond, alkylene radical, group  or more phenyl radicals linked together by groups  combination of several ortho- or peri-condensed phenyl radicals  potassium and Q representing a phenylene radical or a  M representing a hydrogen, sodium, lithium or R3 represents a hydrogen atom or a methyl radical and n represents a number from 1 to 150. <Tb> <tb> <SEP> R3 <SEP> n <SEP> R3 <tb> <SEP> -HN <SEP> - <SEP> - <SEP> CH2 <SEP> - <SEP> CH <SEP> - <SEP> 0 <SEP> - <SEP> CH2 <SEP> - <SEP > CH <SEP> - <SEP> NH <SEP> <tb> diamine)  3 - Copolyamides according to one of claims 1 or 2, characterized in that the aromatic dicarbonyl units they comprise are selected from the units isophthaloyl, terephthaloyl, orthophthaloyl, naphthalene-1,2-dicarbonyl, naphthalene-1,4- dicarbonyl, naphthalene-1,5-dicarbonyl, naphthalene-1,6-dicarbonyl, naphthalene-1,7-dicarbonyl, naphthalene-1,8-dicarbonyl, naphthalene-2,3-dicarbonyl, naphthalene-2,6-dicarbonyl, naphthalene- 2,7-dicarbonyl, 1,1,3-trimethyl-3-phenylindan-4 ', 5-dicarbonyl and are preferably isophthaloyl units.  4 - Copolyamides according to one of claims 1 to 3, characterized in that the aliphatic dicarbonyl units they comprise are selected from succinoyl, glutaroyl, 2-methylsuccinoyl, 2-methylglutaroyl, adipoyl, suberoyl, azeloyl, sebacoyl and are preferably adipoyl units.  5 - Copolyamides according to one of claims 1 to 4, characterized in that the sulfo-aryldicarbonyl units they comprise are selected from the units sulfo-terephthaloyl, sulphoisophthaloyl, sulpho-orthophthaloyl, trisulphonaphthalene2,7-dicarbonyl Sulfo-diphenylsulfone-4,4'-dicarbonyl, sulphodiphenyl-dicarbonyl, sulpho-diphenylmethane-4,4'-dicarbonyl, Sulfo-5-phenoxyisophthaloyl, whose sulphonic acid function is free or is preferably salified by a sodium atom , potassium or lithium and are preferably sodio-5-oxysulfonyl-isophthaloyl units.  6 - Copolyamides according to one of claims 1 to 5, characterized in that the aliphatic diamine units they comprise are selected from the units tetramethylene diamine, 2-methyltetramethylene diamine, pentamethylenediamine, 2-methyl-pentamethylene- diamine, 3-methyl-pentamethylenediamine, 2-ethyl-tetramethylenediamine, hexamethylenediamine, decamethylene diamine and are preferably hexamethylenediamine units.  7 - Copolyamides according to one of claims 1 to 6, characterized in that the oxyalkylene-diamine units they comprise are chosen from 3-oxa-pentamethylenediamine, 3,6-dioxaoctamethylenediamine, 3, 6,9-trioxa-undecamethylenediamine, 3,6,9,12-tetraoxa-tetradecamethylenediamine.  8 - Copolyamides according to one of claims 1 to 7, characterized in that in their formula the molar percentage of sulfo-aryldicarbonyl units relative to all units derived from dicarboxylic acids is between 8% and 25% and preferably between 12% and 18%, the balance consisting of aromatic and / or aliphatic dicarbonyl units.  9 - Copolyamides according to one of claims 1 to 8, characterized in that in their formula the molar percentage of the oxyalkylenediamine units relative to all units derived from diamines is between 10% and 100% and preferably between 50% and 90%, the balance consisting of diamine aliphatic units.  10 - Copolyamides according to one of claims I to 9, characterized in that they have a glass transition temperature (Tg "C) at 85% relative humidity between -50" C and + 100il.  11 - Copolyamides according to one of claims 1 to 10, characterized in that they have a double glass transition temperature at 85% relative humidity, a first located in an area of -500C to + 10C and a second located in an area of + 100C to 1000C.  12 - Process for the preparation of the water-soluble and / or water-dispersible copolyamides according to one of claims 1 to 11, characterized in that they are prepared by reacting one or more aromatic and / or aliphatic dicarboxylic acids, sulfo-aryldicarboxylic acids, one or more aliphatic diamines and one or more oxyalkylenediamines.  13 - Process according to claim 12, characterized in that one uses lactams such as caprolactam or, for a part of the reagents, polyamides such as nylon-6,6, nylon-6 or nylon- 11, in combination with all or part of the monomers indicated above.  14 - Method according to one of claims 12 or 13, characterized in that it comprises a first step which schematically corresponds to the salification of the carboxylic functions of the various acidic monomers by the amine functions of the various amine monomers.  15 - Process according to one of claims 12 to 14, characterized in that salification is carried out in solution in water, the concentration of the various monomers being generally between 20% and 80% by weight per total weight of the mixture reaction.  16 - Method according to one of claims 12 to 15, characterized in that after the salification step the reaction mixture is heated to remove at least a portion of the water present, then the temperature is raised under autogenous pressure, at a value generally between 100ex and 300in, in order to carry out the second stage which corresponds to the polyamidification.  17 - Method according to one of claims 12 to 16, characterized in that during the polyamidification step is used from 0% to 1% by weight relative to the total weight of the various monomers, a catalyst such as hypophosphorous acid, phenylphosphinic acid, phenylphosphonic acid or tris (nonylphenyl) phosphite.  18 - Process according to one of claims 12 to 17, characterized in that, during the polyamidification step, the water is distilled from the reaction medium and the water formed by the reaction.  19 - Process according to one of claims 12 to 14, characterized in that one operates in an organic solvent such as 1,3-dimethyl-imidazolidinone-2 (or dimethylethylene-urea), 1,3-dimethyl -3,4,5,6-tetrahydro-2 (1H) -pyrimidinone (or dimethylpropylene-urea), N-methyl-pyrrolidone, dimethylacetamide.  20 - Use of the water-soluble and / or water-dispersible copolyamides according to one of claims 1 to 11 for sizing textile yarns.  21 - Use for sizing textile yarn chains, aqueous compositions containing from 1% to 50% by weight of water-soluble and / or water-dispersible copolyamides according to one of claims 1 to 12, relative to the total weight of the composition and preferably from 5% to 30%.  22 - Use according to claim 21, characterized in that it consists in applying the water-soluble and / or water-dispersible copolyamides to the threads, by immersion of said threads in an aqueous bath or spraying by said aqueous bath containing the copolyamides at the concentration and the desired temperature, then spinning by passing said son between rolls and finally drying son and glued in hot rooms.  23 - Use according to one of claims 20 to 22, for preparing the synthetic son of polyamides, polyamide fibers, optionally mixed with natural fibers, natural fibers such as cotton, artificial or synthetic fibers, glass fibers and other yarns such as synthetic yarns such as acrylics, polyesters, polyimides, chlorofibre, polyethylene, polypropylene, aramids and their copolymers or artificial yarns such as acetates, triacetates, viscose.