US3664917A

US3664917A - Two-component polyamide yarns

Info

Publication number: US3664917A
Application number: US879594A
Authority: US
Inventors: Rene Grellier; Claude Guyot
Original assignee: RHODIACEDA SOC
Current assignee: RHODIACEDA SOC; SOC RHODIACEDA
Priority date: 1968-11-25
Filing date: 1969-11-24
Publication date: 1972-05-23
Anticipated expiration: 1989-05-23
Also published as: BE742144A; DE1959150A1; LU59868A1; CH508751A; NL6917260A; JPS4910613B1; GB1287305A; NL169204C

Abstract

A composite yarn comprising (a) hexamethylene polyadipamide and (b) a ternary copolyamide prepared from hexamethylenediammonium adipate, hexamethylenediammonium terephthalate and an additional salt derived from an aliphatic dicarboxylic acid containing six to 12 carbon atoms and a hexamethylenediamine or a cycloalkane diamine has a latent crimp which can be developed by heat and is particularly suitable for use in the manufacture of hosiery.

Description

United States Patent Grellier et a1.

TWO-COMPONENT POLYAMIDE YARNS Inventors: Rene Grellier, Chavanoz; Claude Guyot,

Besancon, both of France Assignee: Societe Rhodiaceda, Paris, France Filed: Nov. 24, 1969 Appl. No.: 879,594

Foreign Application Priority Data Oct. 20, 1969 France ..6935853 Nov. 25, 1968 France ..175207 U.S.Cl ..161/173,161/175,161/177, 264/171 Int. Cl ..D02g 3/02 I Field of Search ..161/173, 175, 177; 260/78 R;

264/171, DIG. 26

[451 May 23, 1972 References Cited UNITED STATES PATENTS 2,512,606 6/1950 Bolton et a1 ..260/78 R 3,393,210 7/1968 Speck 3,526,571 9/1970 Ogata "161/175 Primary Examiner-Robert F. Burnett Assistant Examiner-Linda C. Koeckert Attorney-Stevens, Davis, Miller & Mosher ABSTRACT 7 Claims, No Drawings TWO-COMPONENT POLYAM IDE YARNS The invention relates to composite yams comprising two olyamides. By composite yarns are meant yarns of which the constituent filaments have different compositions over different parts of their cross section.

Composite yarns based on at least two polymers having different shrinkage potentials, their production by simultaneous extrusion of the different polymers through the same holes of a spinneret, and their use in hosiery and in woven fabrics are well known.

The use of composite yarns based on two polymers of the same type of chemical nature have already been proposed to help overcome certain disadvantages observed in practice, which result from imperfect cohesion of polymers of difierent chemical nature. Thus the use of yarns comprising two polyamides fulfilling certain crystallization criteria and prepared from a homopolyamide, preferably polyhexamethylene adipamide, and a non-isomorphous copolyamide containing at least 20 percent by weight of each of its components one of these preferably being hexamethylene adipamide has been proposed. The at least 20 percent by weight of the monomer which gives the final copolyamide its nonisomorphous properties may optionally consist of a mixture of monomers each of which whenused alone would make the polyamide non-isomorphous. However, due to this introduction of a considerable amount of additional monomer in order to form a non-isomorphous copolymer, there is a significant difference between the melting points of the two polyarnides constituting the composite yarn, and as a result difficulties in spinning arise and some of the filaments stick together during winding-up.

Composite yarns based on a homopolyamide and a binary copolyamide containing at most 20 percent by weight of nonisomorphous polymer units derived from specific diacids and diamines, the remainder consisting of the same unit as that of the homopolyamide have also been proposed. In this case the melting points of the two polymers are closer together and the spinning difficulties are considerably reduced. However, there is still some difference between the melting points and furthermore, when the yarns on the spinning bobbin take up moisture, due to the amount of the amorphous phase, some filaments of the yarn become stuck together.

The present invention provides a composite yarn which comprises as its polymer components (a) polyhexamethyleneadipamide and (b) a ternary copolyamide prepared from hexamethylenediammonium adipate, 5-25 percent (based on the total weight of the salts) of hexamethylenediammonium terephthalate, and 5-20 percent (on the same basis) of an additional salt derived from an aliphatic dicarboxylic acid containing six to 12 carbon atoms in the molecule and (i) an unsubstituted or C alkyl-substituted hexamethylenediarnine or (ii) a cycloalkane diamine of the formula:

NH RNH wherein R represents (CH2) m (CH2) n R1 R, Ill! or Q I'ti L wherein m is an integer from 1 to 4, n and n are or integers from 1 to 4, p is an integer from 1 to 6, R is H, CH or C H and R is H, CH C H or cyclohexyl.

Where these cycloalkane diamines exsist as structural isomers, they can be used in the pure form or as an isomer mixture as desired.

Suitable diamine components of the additional salt include hexamethylenediamine, trimethylhexamethylenediamine, 3- aminomethyl-3,5 ,S-trimethyl-cyclohexylaminel di( 4-aminocyclohexyl)methane and 2,2-bis(4-aminocyclohexyl propane. Trimethylhexamethylenediamine is particularly valuable as a substituted hexamethylenediamine.

Among the aliphatic dicarboxylic acid components of the additional salt adipic, sebacic and dodecanedioic acids may be particularly mentioned, though if the diamine used is hexamethylenediamine the diacid must obviously be other than adipic acid. 1

The ternary copolyamides can be made by general methods which are well known in the art, as can the monomers from which they are made,

The polyhexamethylene adipamide and the ternary copolyamide are preferably present in the yarn in substantially equal proportions by weight.

This new type of yarn has several substantial advantages due to the presence of terephthalate units as one of the constituents in the ternary copolyamide.

It is found that these yarns are easily spun and also that the individual filaments do not stick together during cooling, because of the very small difference between the melting points of the two constituents. Further it is found that these yams do not stick together during winding-up when they take up moisture. In fact, a ternary copolyamide containing hexamethylene adipamide units, units derived from hexamethylenediammonium terephthalate, and units derived from an additional monomer salt which confers nonisomorphous properties on the final copolyamide, as described above, can have a higher melting point than a binary copolyamide produced from hexamethylenediammonium adipate and an identical proportion of the same additional monomer salt.

The increase in the melt viscosity resulting from the presence of these additional monomer units also helps to improve the spinning of the yarn, especially permitting to put the bundle under greater tension. This increased melt viscosity also makes it possible to use a higher viscosity polyhexamethylene adipamide as the other constituent. Thus the composite yarns of improved strength may be obtained.

The units derived from hexamethylene diammonium terephthalate in the ternary copolyamide enable copolyamides with a high crystallization peak to be obtained and thus the stretching of the yarn to be carried out under more severe conditions. I

The crystallization peak and the melting peak are measured by differential enthalpy analysis, under nitrogen using a temperature rise of 8 C per minute, of a previously melted and quenched sample. The temperatures corresponding to the start, the maximum and the end of the crystallization and melting peaks can thus be observed. The area of the peak, which is proportional to the degree of crystallization, is given in the Examples for a weight of polymer of 10 mg.

Finally, the latent crimp of the yarns of this invention is greater than that of comparable yarns obtained from binary copolyamides containing no terephthalamide units. The latent crimp can be developed by heating to rather high temperatures, but the crimp obtained is more stable to possible temperature variations to which the yarn may be subsequently subjected.

The percentage of hexamethylenediammonium terephthalate in the copolyamide required to confer these properties on the copolymer varies within the range of 5 to 25 percent by weight. The advantages obtained using copolyamides prepared from less than 5 percent by weight are negligible while using amounts greater than 25 percent by weight it is difficult to obtain a copolyamide having a melt viscosity similar to that of the polyhexamethylene adipamide. [Considerable differences between the melt viscosities of the two constituents of the yarn gives rise to difficulties in spinning]. Preferably, 10 to 15 percent by weight of hexamethylenediammonium terephthalate are used in the preparation of the eopolyamide. The proportion of units derived from the additional monomer salt in the eopolyamide varies within the range of 5 to 20 percent by weight depending on the desired crimp and on the nature of the additional monomer salt which leads to the non-isomorphous copolymer used.

The yarns can be obtained by a conventional melt spinning process by simultaneous extrusion of two polymers, alongside one another or in the form of a non-concentric core and sheath, through the same holes of a spinneret, the ratio of the throughputs rates is preferably substantially 1:1 but can be as low as 1/3, to give a ratio of polyhexamethylene adipamide to eopolyamide of 1:3 by weight or as great as 3:1. The yarns so formed are stretched, as by passing them under tension round a snubbing pin, which may be heated, without bringing the yarn to a temperature which would cause appreciable crystallization of the copolymer, and the crimp is subsequently developed by heat treatment, for example treatment of the yarn in the tension free state or of an article produced from the yarn with boiling water. Where the heat-treatment is carried out on a textile article, it may advantageously be combined with the dyeing operation.

The crimp obtained is characterized by the extensibility of the yarn and by the half-decrimping and half-recrimping forces. The springiness of the crimp and hence its resistance to decrimping is, for a given extensibility, directly dependent on the magnitude of these forces. This resistance to decrimping is important during handling or use of the yarn.

The extensibility is given by the formula:

Wherein L is the length of the decrimped yarn under a load of 225 mg/dtex and l is the length of the crimped yarn in a tension-free state.

The measurements may be carried out using an INSTRON tensometer, the crimp being pulled out and then allowed to return. Graphs are drawn for the range I to L and the extensibility is read off as the abcissa and the half-decrimping and half-recrimping forces as the ordinate.

The composite yarns obtained from these ternary eopolyamides and polyhexamethyleneadipamide may with particular advantage be used in hosiery because of their elasticity and strength and because they impart to the article an attractive appearance and an agreeable feel. They may also be used in the manufacture of other knitted fabrics and woven fabrics and carpets.

The following Examples illustrate the invention.

EXAMPLE 1 Polyhexamethylene adipamide and a eopolyamide produced from hexamethylenediammonium adipate, hexamethylene-diammonium terephthalate and hexamethylenediammonium sebacate in proportions of 67/17/16 by weight are extruded alongside one another at 290 C, simultaneously in a 1:1 weight ratio and at the same throughput, through the same holes of a hole spinneret using a conventional melt spinning device.

On issuing from the spinneret the monofilament yarns travel through an atmosphere of a cooling gas and are then wound up at 420 m/minute.

They are then stretched at ambient temperature in a ratio of 4.12 by being passed at a speed of 540 m/minute over a stretching rod 8 mm in diameter. The crimp is developed in boiling water, the yarns being kept in a tension-free state. The yarns then possess the following properties:

Gauge (dtex) l7 Tensile strength (g/dtex) 4.45 Elongation at break 36 Extensibility 160 Half-decrimping force (mg/dtex) 4.5 Half-recrimping (mg/dtex) 1.8

They are used in the manufacture of stockings having good elasticity and which take the shape of the leg well.

EXAMPLE 2 A composite yarn is prepared by the method of Example 1 except that the hexamethylenediammonium sebacate is replaced by di(4-aminocyc1ohexyl)methane adipate and also the proportions of the constituents of the eopolyamide being 65/ 1 5/20 by weight.

The two polymers are simultaneously extruded at 292 C through the holes of a 30 hole spinneret, the ratio of the throughputs of the homopolyamide and of the eopolyamide being 60/40. The resulting yarns are wound up at 300 m/rninute.

They are then stretched in a ratio of 4.5 by being passed at a speed of 3 10 m/minute over a rod heated to 70 C.

After treatment in the tension-free state with boiling water, the yarns possess the following properties:

Overall gauge (dtex) 550 Tensile strength (g/dtex) 4.45 Elongation at break 37.2 Extensibility Half-decrimping force (mg/dtex) l 1.07 l-lalf-recrimping force (mg/dtex) 5.85

These yarns are used in the manufacture of carpets by known methods. They show good uniformity and good dyeing affinity.

EXAMPLE 3 Composite yarns are prepared by the procedure of Example 1 except that the hexamethylenediammonium sebacate is replaced by di(4-aminocyclohexyl)methane sebacate, the proportions of the constituents in the eopolyamide then being 70/15/15 by weight.

The two polymers are extruded at 290 C simultaneously in a 1:1 weight ratio and at the same throughput through the holes of a spinneret possessing three series of 10 holes and the composite yarns obtained are wound up at a speed of 600 m/minute.

They are then stretched at ambient temperature in a ratio of 4.02 by being passed at a speed of 470 m/minute over a stretching rod 6 mm in diameter.

The yarns in the tension-free state, are dipped in boiling water to develop the crimp. They then possess the following properties:

Overall gauge (dtex) 22 Tensile strength (g/dtex) 4.83 Elongation at break 32.3 Extensibility Half-decrimping force (mg/dtex) 9.54 Halfrecrimping force (mg/dtex) 5.13

The yarns are used for the manufacture of very elastic stockings and have an attractive appearance on the leg.

EXAMPLE 4 Composite yarns are prepared as in Example 1 except that the hexamethylenediammonium sebacate is replaced by 3- amin0methyl-3,5,5-trimethyl-cyclohexylamine-l adipate, the proportions of the constituents of the eopolyamide being 75/ 10/15 by weight. The two polyamides are extruded simultaneously in a 1:1 weight ratio and at the same throughput at 292 C through the same holes of a spinneret having two series of 24 holes, and the yams obtained are wound up at a speed of 600 m/minute.

After being stretched at ambient temperature to a ratio of 3.95 by being passed at a speed of 520 m/minute over a rod 6 mm in diameter, the yarns obtained are dipped in the tensionfree state into boiling water to develop the crimp. They then have the following properties:

Overall gauge (dtex) 78 Tensile strength (g/dtex) 4.41 Elongation at break 34 Extensibility 160 Half-decrimping force (mg/dtex) 1 1.61 Half-recrimping force (mg/dtex) 6.75

r EXAMPLE 5 Composite yarns are prepared under the same conditions as described in Example 4, using polyhexamethylene adipamide and a copolyamide produced from hexamethylenediammonium adipate, hexamethylenediammonium terephthalate and di(4-aminocyclohexyl)methane adipate, in the proportions of 65/15/20 by weight.

After being stretched and treated with boiling water, the yarns have the following properties:

Overall gauge (dtex) 78 Tensile strength (g/dtex) 3.96 Elongation at break 32 Extensibility 130 Half-decrimping force (mg/dtex) 13.05 Half-recrimping force (mg/dtex) 5.85

EXAMPLE 6 Polyhexamethylene adipamide and a copolyamide produced from hexamethylenediammonium adipate, hexamethylenediammonium terephthalate and 2,2-bis(4-aminocyclohexyl)-propane dodecanoate (containing 68 percent of the trans-trans isomer, 30 percent of the cis-trans isomer and 2 percent of the cis-cis isomer), in the proportions of 70/15/15 by weight, are extruded at 292 C alongside one another, simultaneously in a 1:] weight ratio and with the same throughput, through the same holes of a spinneret possessing two series of 24 holes, using a conventional melt spinning device.

On issuing from the spinneret the yarns travel through an atmosphere of a cooling gas and are then wound up at the rate of 600 m/minute.

They are then stretched at ambient temperature in a ratio of 3.95 by passing them at a speed of 520 m/minute over a stretching rod 6 mm in diameter. The crimp is developed by treating the yarns with boiling water, the yams being kept in a tension-free state. The resulting yarns have the following properties:

Overall gauge (dtex) 78 Tensile strength (g/dtex) 3.75 Elongation at break 3O Extensibility 170 Half-decrimping force (mg/dtex) 8.5 Half-recrimping force (mg/dtex) 2.2

EXAMPLE 7 A composite yarn is produced under the same conditions as described in Example 6 except that the 2,2-bis(4-aminocyclohexyl)propane dodecanoate is replaced by 3- aminomethyl-3,5,5-trimethyl-cyclohexylamine-1 adipate, the ratio of the constituents being 75/15/10 by weight.

The properties of the copolyamide used are summarized in Table I below:

TABLE I (Start 235 Melting peak (C) (Maximum 254 (End 258 (Start 90 Crystallization peak (C) (Maximum 93 (End 96 Area of the crystallization peak (mm) 465 The crimped yarn obtained after stretching and heat treatment has the following properties:

Overall gauge (dtex) 78 Extensibility 120 Half-decrimping force in (mg/dtex) 10.5 Half-recrimping force in (mg/dtex) 4.1 i

This crimped yarn is of good quality, free of filaments which are stuck together and the crimp is very regular.

are prepared as described in Example 6 from polyhexamethylene adipamide and a copolyamide produced from hexamethylenediammonium adipate, hexamethylenediammonium terephthalate and a salt of a diacid having six or 10 carbon atoms and an aliphatic or cycloaliphatic diamine.

The properties of the copolyamides used are summarized in Table 11 below:

TABLE 11 Examples 8 9 10 11 Diamine in the additional Hexamethylene S-aminomethylsalt diamine 3,5,5-trimethylcyclohexylamine-l Diacid in the additional sebacic acid adipic acid salt Percentage by weight of hexamethylenediammonium terephthalate based on 25 15 5 10 the total weight of salts Percentage by weight of additional salt based on l5 l5 l0 10 the total weight of salts (Start 222 239 241 240 Melting peak (C) (Maximum 242 250 255 254 (End 247 254 258 257 (Start 68 76 81 Crystallization (Maximum 73 72 79 84 peak (C) (End 77 82 87 Area of the crystallization 435 470 475 500 peak (mm After having been stretched and heat treated, the yarns have an attractive crimp and good strength and can be used for the manufacture of valuable textile articles.

We claim:

1. A composite yarn whose constituent filament or filaments have a side-by-side or non-concentric sheath core structure which consists essentially of as its polymer components (a) polyhexamethylene adipamide and (b) a ternary copolyamide prepared from hexamethylenediammonium adipate, 5 to 25 percent (based on the total weight of the salts) of hexamethylenediammonium terephthalate, and 5 to 20 percent (on the same basis) of an additional salt derived from an aliphatic dicarboxylic acid containing six to 12 carbon atoms in the molecule and a diamine selected from the group consisting of unsubstituted hexamethylenediamines, C alkyl-sub stituted hexamethylene diamines and cycloalkane diamines of the fonnula:

Nl-b-R-Nl-l wherein R is selected from the group consisting of (R )n and 1 1 R, l 'l l l R1 J.

wherein m is an integer from 1 to 4, n and n are integers from 0 to 4, p is an integer from 1 to 6, R is selected from the group consisting of H, CH and C H and R is selected from the group consisting of H, CH ,C H and cyclohexyl.

2. A yarn according to claim 1, wherein the proportion of units derived from hexarnethylenediammonium terephthalate in the ternary copolyamide is 10 to 15 percent.

3. A yarn according to claim 1, wherein the diamine constituent of the third component of the ternary copolyamide is sebacic and dodecanedoic acid subject to the proviso that if hexamethylenediamine is used, the dicarboxylic acid is not adipic acid.

6. A yarn according to claim 1, wherein the additional salt is selected from the group consisting of hexamethylenediammonium sebacate, di(4-aminocyclohexyl)methane adipate, di(4-aminocyclohexyl)methane sebacate, S-aminomethyl- 3,5,S-trimethylcyclohexylarnine-l adipate, and 2,2-bis(4- aminocyclohexyl )propane dodecanoate.

7. A yarn according to claim 1, containing substantially equal proportions by weight of the polyhexamethylene adipamide and the ternary copolyamide.

Claims

2. A yarn according to claim 1, wherein the proportion of units derived from hexamethylenediammonium terephthalate in the ternary copolyamide is 10 to 15 percent.
3. A yarn according to claim 1, wherein the diamine constituent of the third component of the ternary copolyamide is selected from the group consisting of hexamethylenediamine, trimethylhexamethylenediamine, 3-amino-methyl-3,5,5-trimethylcyclohexylamine-1, di(4-aminocyclo-hexyl)methane and 2, 2-bis(4-aminocyclohexyl)propane.
4. A yarn according to claim 1, wherein the dicarboxylic acid constituent of the third component of the ternary copolyamide is selected from the group consisting of adipic, sebacic and dodecanedioic acid subject to the proviso that if hexamethylenediamine is used, the dicarboxylic acid is not adipic acid.
5. A yarn according to claim 3, wherein the dicarboxylic acid constituent of the third component of the ternary copolyamide is selected from the group consisting of adipic, sebacic and dodecanedoic acid subject to the proviso that if hexamethylenediamine is used, the dicarboxylic acid is not adipic acid.
6. A yarn according to claim 1, wherein the additional salt is selected from the group consisting of hexamethylenediammonium sebacate, di(4-aminocyclohexyl)methane adipate, di(4-aminocyclohexyl)methane sebacate, 3-aminomethyl-3,5,5-trimethylcyclohexylamine-1 adipate, and 2,2-bis(4-aminocyclohexyl)propane dodecanoate.
7. A yarn according to claim 1, containing substantially equal proportions by weight of the polyhexamethylene adipamide and the ternary copolyamide.