SOFT HAND COPOLYAMIDE COMPOSITION

Abstract

Composition comprising, on a weight basis, the total being equal to 100%: from 98% to 100% of at least one copolyamide bearing amide units and polyether units, having a melting point (T.sub.m) from about 90 to about 150 C., in particular from about 100 C. to about 125 C., and having a flexural modulus of less than 100 MPa, as determined according to standard ISO 178 (2010); from 0 to 2% of at least one additive chosen from stabilizers and dyes, or a mixture thereof,
for the manufacture of a heat-sensitive adhesive, in particular a veil, a film, granules, a filament, a grate, a powder or a suspension.

Claims

1. Composition comprising, on a weight basis, the total being equal to 100%: from 98% to 100% of at least one copolyamide bearing amide units and polyether units, having a melting point (T.sub.m) from about 90 to about 150 C., and having a flexural modulus of less than 100 MPa, as determined according to standard ISO 178 (2010); the said amide unit having the following structure:
(A).sub.x/(B).sub.y/(C) resulting from the condensation of unit (A), unit (B) and unit (C), in which: x=0 or 1, y=0 or 1 and x+y=1 or 2, A and B corresponding to an aliphatic repeating unit chosen from a unit obtained from at least one amino acid and a unit obtained from at least one lactam, or a unit X.Y obtained from the polycondensation: of at least one diamine, the said diamine being chosen from a linear or branched aliphatic diamine, a cycloaliphatic diamine and an aromatic diamine or a mixture thereof, and of at least one dicarboxylic acid, the said diacid being chosen from: an aliphatic diacid, a cycloaliphatic diacid and an aromatic diacid, the said diamine and the said diacid comprising from 4 to 36 carbon atoms; (C) represents a long-chain aliphatic repeating unit, obtained from an amino acid, a lactam, or a unit X.Y, of C10 or more, or a mixture thereof, and (A) and (B) being different from each other when they are both present, and (A) and (B) being different from (C) when they are present alone or together, the weight proportion of polyether units in the copolyamide being greater than 40%, from 0 to 2% of at least one additive chosen from stabilizers and dyes, or a mixture thereof.

2. Composition according to claim 1, in which the said at least one diamine is chosen from a linear or branched aliphatic diamine and a cycloaliphatic diamine or a mixture thereof, and the said diacid is chosen from an aliphatic diacid and a cycloaliphatic diacid or a mixture thereof.

3. Composition according to claim 1, in which the weight proportion of long-chain aliphatic repeating unit in the said amide unit is from 50% to 95%.

4. Composition according to claim 1, in which the polyalkylene ether polyol is chosen from PPG, PTMG or a PEG-PPG mixture and/or the polyalkylene ether polyamine is chosen from an Elastamine or a Jeffamine predominantly bearing PPG or PTMG blocks.

5. Composition according to claim 1, in which the said amide unit is chosen from one of the following structures: 6/X.Y/(C) and Pip.Y/X.Y/C, X, Y and C being as defined above and Pip denoting piperazine.

6. Composition according to claim 5, in which the said amide unit is chosen from: 6/6.6/12, 6/6.10/12, 6/11/12, Pip.10/6.10/12.

7. Composition according to claim 6, in which the weight proportion of each constituent of the 6/11/12 amide unit is 20/10/70.

8. Composition according to claim 1, in which the said amide unit is chosen from one of the following structures: A/C and X.Y/C, A corresponding to an aliphatic repeating unit chosen from a unit obtained from at least one amino acid and a unit obtained from at least one lactam and X.Y being as defined above.

9. Composition according to claim 8, in which the said amide unit is chosen from: 6/12, 11/12, 6.10/12 and Pip.10/12.

10. Composition according to claim 9, in which the weight proportion of each constituent of the 6/12 amide unit is 25/75 or 30/70.

11. Heat-sensitive adhesive of the HMA (hot-melt adhesive) type consisting of the composition according to claim 1.

12. Heat-sensitive adhesive according to claim 11, chosen from a veil, a film, granules, a filament, a grate, a powder and a suspension.

13. Heat-sensitive adhesive according to claim 11, the said adhesive having a thickness of from 20 to 55 m and an adherence to a textile of greater than 3 N/cm, as determined by the T peel test at 100 mm/min.

14. Heat-sensitive adhesive according to claim 11, the said adhesive having a thickness of from 55 to 90 m and an adherence to a textile of greater than 5 N/cm, as determined by the T peel test at 100 mm/min.

15. Heat-sensitive adhesive according to claim 13, in which the adherence is determined at a lamination temperature of from 120 to 180 C.

16. Heat-sensitive adhesive according to claim 11, having a loss of adherence after at least two washes at 40 C. from about 2% to about 18%.

17. Heat-sensitive adhesive according to claim 11, having a loss of adherence after at least two washes at 60 C. from about 2% to about 30%.

18. A composition as defined in claim 1, configured for use in the manufacture of a heat-sensitive adhesive.

19. A method of using the heat-sensitive adhesive as defined in claim 11 in the textile industry.

Description

DESCRIPTION OF THE FIGURES

[0212] FIG. 1 shows the initial adhesion (or adherence) force in N/cm as a function of the lamination temperature, of films of 30 m or 60 m of TPU (1: Tm=100 C., 2: Tm=120 C., 3: Tm=150 C.) or of the invention (6/12/PTMG (1000/1000, MW amide units and polyether units, respectively): composition 1, Tm=110 C.) laminated on cotton (cotton: 90%, polyester: 10%) or Lycra at various temperatures.

[0213] From left to right:

[0214] Lamination temperature=120 C.: 14 N/cm: 6/12/PTMG and 4 N/cm: TPU1 (films of 30 m on cotton);

[0215] Lamination temperature=120 C.: 12 N/cm: 6/12/PTMG and 6 N/cm: TPU1 (films of 30 m on Lycra);

[0216] Lamination temperature=140 C.: 11 N/cm: 6/12/PTMG and 2 N/cm: TPU2 (films of 60 m on cotton);

[0217] Lamination temperature=160 C.: 16 N/cm: 6/12/PTMG, 4 N/cm: TPU2 and 2 N/cm: TPU3 (films of 60 m on cotton);

[0218] Lamination temperature=180 C.: 22 N/cm: 6/12/PTMG and 3 N/cm: TPU3 (films of 60 m on cotton).

[0219] Irrespective of the film thickness, the fabric used and the lamination temperature, the adhesion (or adherence) of the films of the invention is very markedly superior to that of the three TPUs used.

[0220] FIG. 2 shows the resistance to washing at 40 C. of films of 60 m of TPU (2: Tm=120 C., 3: Tm=150 C.) or of the invention (6/12/PTMG (1000/1000 MW amide units and polyether units, respectively): composition 1, Tm=110 C.) on cotton (cotton: 90%, polyester: 10%) as a function of the lamination temperature.

[0221] From left to right:

[0222] Lamination temperature=140 C.: 82%: 6/12/PTMG and 50%: TPU2;

[0223] Lamination temperature=160 C.: 98%: 6/12/PTMG, 79%: TPU2 and 50% TPU3;

[0224] Lamination temperature=180 C.: 98%: 6/12/PTMG and 67%: TPU3.

[0225] The resistance to washing at 40 C. of the films of the invention is very markedly superior to that of the TPUs irrespective of the lamination temperature.

[0226] FIG. 3 shows the resistance to washing at 60 C. of films of 60 m of TPU (1: Tm=100 C., 2: Tm=120 C., 3: Tm=150 C.) or of the invention (6/12/PTMG (1000/1000, MW amide units and polyether units, respectively): composition 1, Tm=110 C.) on cotton (cotton: 90%, polyester: 10%) or Lycra as a function of the lamination temperature.

[0227] Lamination temperature=120 C.: 91%: 6/12/PTMG and 17%: TPU1 (films of 30 m on cotton);

[0228] Lamination temperature=120 C.: 89%: 6/12/PTMG and 71: TPU1 (films of 30 m on Lycra);

[0229] Lamination temperature=140 C.: 73%: 6/12/PTMG and 25%: TPU2 (films of 60 m on cotton);

[0230] Lamination temperature=160 C.: 75%: 6/12/PTMG, 66%: TPU2 and 25% TPU3 (films of 60 m on cotton);

[0231] Lamination temperature=180 C.: 96%: 6/12/PTMG and 60%: TPU3 (films of 60 m on cotton).

[0232] The resistance to washing at 60 C. of the films of the vention is very markedly superior to that of the TPUs irrespective of the lamination temperature, the textile used or the thickness of the film.

EXAMPLES

Example 1

Compositions of the Invention

[0233] Compositions are prepared according to the techniques known to those skilled in the art.

[0234] The melting point is measured by DSC (differential scanning calorimetry) according to standard 11357-3 (2013) or according to DIN 53736, Volume B (visual determination of the melting point of semi-crystalline polymers) optically using a heating bench and a microscope.

[0235] Composition 1: 6/12/PTMG (1000/1000, PA6/PA12 (30/70). DSC 1.sup.st heating: 114.8 C. [0236] The composition is detailed in Table I below:

TABLE-US-00007 TABLE I Starting material Weight Unit Sebacic acid 4.63 kg PTMG1000 22.46 kg Lactam 6 5.40 kg Lactam 12 12.60 kg Water 4.00 kg Anti-UV 225.00 g Antioxidant 135.00 g Zirconium 67.50 g butoxide

[0237] Composition 2: 6/12/PTMG (1000/1000, PA6/PA12 (25/75)).

[0238] DSC 1.sup.st heating: 124.6 C. [0239] The composition is detailed in Table II below:

TABLE-US-00008 TABLE II Starting material Weight Unit Sebacic acid 4.63 kg PTMG1000 22.46 kg Lactam 6 4.50 kg Lactam 12 13.50 kg Water 4.00 kg Anti-UV 225.00 g Antioxidant 135.00 g Zirconium 67.50 g butoxide

[0240] Composition 3: 6/11/12/PTMG (1000/1000, PA6/PA11/PA12 (20/10/70)). [0241] DSC 1.sup.st heating: 116.5 C. [0242] The composition is detailed in Table III below:

TABLE-US-00009 TABLE III Starting material Weight Unit Sebacic acid 4.63 kg PTMG1000 22.46 kg Lactam 6 3.60 kg Amino 11 1.80 Lactam 12 12.60 kg Water 4.00 kg Anti-UV 225.00 g Antioxidant 135.00 g Zirconium 67.50 g butoxide

Example 2

Test of Adhesion (or Adherence) of the Compositions of the Invention

[0243] Lamination machine: model HP-450M,MS [0244] Pressure: 1.0 kg/cm.sup.2 [0245] Bonding time: 25 sec [0246] Peeling machine: Hongda Tensometer [0247] Peel test at 100 mm/min [0248] Type of HMA [0249] 6/12/PTMG (composition 1) [0250] 3 different types of aliphatic or aromatic TPU: TPU1: Tm=100 C., TPU2: Tm=120 C., TPU3: Tm=150 C., sold by Bayer under the brand name Desmapan or BASF under the brand name Elastollan. [0251] Types of textiles: [0252] Cotton (cotton 90%, polyester 10%) [0253] Lycra [0254] The adhesion (or adherence) tests are presented in FIG. 1.

Example 3

Resistance to Washing

[0255] The various heat-sensitive adhesives are subjected to two machine washes for 1 hour 30 minutes for each wash and then to drying.

[0256] The washing tests are presented in FIGS. 2 and 3.

[0257] Comparison of the Heat-Sensitive Adhesive Properties

[0258] Table IV presents the comparison of the properties of a heat-sensitive adhesive consisting of a composition of the invention (6/12/PTMG: 1000/1000): composition 1 with those of TPU or of a standard copolyamide.

TABLE-US-00010 TABLE IV PROPERTIES TPU Standard CoPA Composition 1 Soft hand ++ + Resistance to Up to 40 C. From 40 C. to 90 C. Up to 60 C. washing Yellowing + + Implementation + +

[0259] means that the product does not have the property under consideration.

[0260] + means that the product has the property under consideration in satisfactory manner.

[0261] ++ means that the product has the property under consideration in an excellent manner.

[0262] The soft hand determines the flexibility of the compound.

[0263] The comparison of the observed properties shows that only the adhesive of the invention has the four properties described in this figure.

[0264] Table V shows the comparison of the major properties of various heat-sensitive adhesives.

TABLE-US-00011 TABLE V 6/6.12/11/PEG.12 6/12/PTMG at 25/20/25130 (1000/1000) PROPER- Standard Comparative Composition TIES TPU CoPA composition 1 Modulus 5 300 200 90 at 23 C. Resistance to Up to From Up to 40 C. Up to 60 C. washing 40 C. 40 C. to 90 C. Tm 80 to 80 to 100 C. 110 C. 150 C. 135 C.

[0265] The TPUs have a suitable modulus but are not resistant to washing. Moreover, they are difficult to implement for the preparation of films.

[0266] The standard CoPAs show very good resistance to washing but have an excessively high modulus for the heat-sensitive adhesive application.

[0267] 6/6.12/11/PEG.12 shows poor resistance to washing and moreover has an excessively high modulus for the heat-sensitive adhesive application.

[0268] Only the compounds of the invention of CoPA/PTMG type have both satisfactory modulus and wash-resistance values.