FLEXIBLE POLYAMIDE

Abstract

A flexible polyamide including a unit formed from an aliphatic dicarboxylic acid (A1) having 18 or more carbon atoms and/or a unit formed from an aliphatic diamine (B1) having 18 or more carbon atoms, wherein the polyamide has a total content of 10 to 90% by mass of the unit formed from (A1) and the unit formed from (B1) and has a melting point of 240° C. or higher.

Claims

1. A flexible polyamide comprising a unit formed from an aliphatic dicarboxylic acid (A1) having 18 or more carbon atoms and/or a unit formed from an aliphatic diamine (B1) having 18 or more carbon atoms, wherein the polyamide has a total content of 10 to 90% by mass of the unit formed from the aliphatic dicarboxylic acid (A1) having 18 or more carbon atoms and the unit formed from the aliphatic diamine (B1) having 18 or more carbon atoms, and has a melting point of 240° C. or higher.

2. The flexible polyamide according to claim 1, wherein the polyamide has a tensile elongation at break of 30% or more.

3. The flexible polyamide according to claim 1, wherein the aliphatic dicarboxylic acid (A1) having 18 or more carbon atoms is dimer acid.

4. The flexible polyamide according to of claim 1, wherein the aliphatic diamine (B1) having 18 or more carbon atoms is dimer diamine.

5. The flexible polyamide according to claim 1, comprising a unit formed from a dicarboxylic acid (A2) having 12 or less carbon atoms.

6. The flexible polyamide according to 1, comprising a unit formed from a diamine (B2) having 12 or less carbon atoms.

7. The flexible polyamide according to claim 5, wherein the dicarboxylic acid (A2) having 12 or less carbon atoms is terephthalic acid.

8. The flexible polyamide according to claim 6, wherein the diamine (B2) having 12 or less carbon atoms is 1,10-decanediamine.

9. The flexible polyamide according to claim 1, comprising no segments formed of polyether or polyester.

10. A molded body constructed by molding the flexible polyamide according to claim 1.

11. A method for manufacturing the flexible polyamide according to claim 1, wherein polymerization is conducted at a temperature equal to or lower than the melting point of the polyamide.

Description

EXAMPLES

[0059] The present invention will be described in more detail with reference to the following examples, however, the scope of the present invention is not limited thereto.

A. Evaluation Method

[0060] The characteristics of polyamides were obtained by the following methods.

(1) Composition

[0061] The pellets and powder obtained were analyzed by .sup.1H-NMR using a high-resolution nuclear magnetic resonance apparatus (ECA-500NMR manufactured by JEOL Ltd.), and the resin composition was determined from the peak intensity of each copolymer component (resolution: 500 MHz, solvent: mixed solvent with a volume ratio of deuterated trifluoroacetic acid and deuterated chloroform of 4/5, temperature: 23° C.)

(2) Melting Point

[0062] A few mg of the obtained pellets and powder was sampled, and a temperature of the sample was raised to 350° C. at a heating rate of 20° C./min by using a differential scanning calorimeter DSC-7 (manufactured by PerkinElmer, Inc.), then held at 350° C. for 5 minutes, lowered to 25° C. at a cooling rate of 20° C./min, and further held at 25° C. for 5 minutes. The top of the endothermic peak observed when the temperature of the sample was raised again at a heating rate of 20° C./min, was defined as a melting point.

[0063] The thermal resistance was evaluated from the measurement value of the melting point according to the following criteria. [0064] S: Not lower than 300° C. [0065] A: Not lower than 270° C. and lower than 300° C. [0066] B: Not lower than 240° C. and lower than 270° C. [0067] C: Lower than 240° C.

(3) Melt Flow Rate (MFR)

[0068] By using the obtained pellets and powder, measurement was carried out at 340° C. and a load of 1.2 kgf according to JIS K7210.

[0069] (4) Tensile Strength, Tensile Elastic Modulus, Tensile Elongation At Break

[0070] After the obtained pellets and powder were sufficiently dried, they were molded by using an injection molding machine under the conditions of a cylinder temperature of 340° C. and a mold temperature of 80° C., and test pieces (dumbbell pieces) for measuring general physical properties conforming ISO standard were fabricated. By using the obtained test piece, the tensile strength, tensile elastic modulus, and tensile elongation at break were measured according to ISO178.

[0071] A flexibility was evaluated from the measurement value of tensile elongation at break according to the following criteria. [0072] S: Not less than 150% [0073] A: Not less than 100% and less than 150% [0074] B: Not less than 30% and less than 100% [0075] C: Less than 30%

[0076] Moreover, the flexibility was evaluated from the measurement value of tensile elastic modulus according to the following criteria. [0077] S: Not more than 400 MPa [0078] A: Exceeding 400 MPa and not more than 1200 MPa [0079] B: Exceeding 1200 MPa and not more than 1800 MPa [0080] C: Exceeding 1800 MPa

(5) Shore-D Hardness

[0081] By using the test pieces obtained in (4) above, measurement was carried out in accordance with ASTM D 2240.

[0082] A flexibility was evaluated from the measurement value of Shore-D according to the following criteria. [0083] S: Not more than 60 [0084] A: Exceeding 60 and not more than 70 [0085] B: Exceeding 70 and not more than 80 [0086] C: Exceeding 80

B. Raw Material

[0087] The following materials were used as dimer acid and dimer diamine. [0088] Dimer acid: Pripole 1009 manufactured by Croda International plc. [0089] Dimer diamine: Priamine 1075 manufactured by Croda International plc.

Example 1

[0090] In a reaction vessel equipped with a heating mechanism and a stirring mechanism, 26.7 parts by mass of dimer acid, 25.3 parts by mass of dimer diamine, 23.5 parts by mass of terephthalic acid, 24.4 parts by mass of 1,10-decanediamine, and 0.1 parts by mass of sodium hypophosphite monohydrate, were charged.

[0091] Thereafter, the mixture was heated to 260° C. with stirring, and polymerization was carried out under a nitrogen stream at normal pressure and 260° C. for 5 hours while removing condensed water from the system. During the polymerization, the system was in suspension.

[0092] After completion of the polymerization, the product was removed, cut and dried to obtain polyamide pellets.

Examples 2 to 12, 14, and Comparative Example 2

[0093] Polyamide pellets were obtained by carrying out the same operation as in Example 1 except that the monomers to be charged into the reaction vessel were changed as shown in Tables 1 and 2.

Example 13

[0094] In a reaction vessel equipped with a heating mechanism and a stirring mechanism, 25.5 parts by mass of dimer acid, 24.1 parts by mass of dimer diamine, 28.0 parts by mass of adipic acid, 22.3 parts by mass of 1,6-hexanediamine, and 0.1 parts by mass of sodium hypophosphite monohydrate were charged. Thereafter, the mixture was heated to 270° C. under sealing with stirring, and polymerized at 270° C. for 3 hours. Then, the pressure was gradually lowered to normal pressure, and the polymerization was further carried out for 1 hour. During the polymerization, the system was in suspension.

[0095] After the polymerization was completed, the product was removed, cut and dried to obtain polyamide pellets.

Comparative Example 1

[0096] Into a powder stirring device equipped with a heating mechanism, 49.0 parts by mass of terephthalic acid and 0.1 parts by mass of sodium hypophosphite monohydrate were charged. While stirring heating at 170° C., 50.9 parts by mass of 1,10-decanediamine was added little by little over 3 hours to obtain a nylon salt. Then, the nylon salt was heated to 250° C. with stirring, and polymerization was carried out under a nitrogen stream at normal pressure and 250° C. for 7 hours while removing condensed water from the system. During the polymerization, the system was in powder form.

[0097] After completion of the polymerization, the product was removed to obtain polyamide powder.

Comparative Example 3

[0098] Into a reaction vessel equipped with a heating mechanism and a stirring mechanism, 51.3 parts by mass of dimer acid, 48.6 parts by mass of dimer diamine, and 0.1 parts by mass of sodium hypophosphite monohydrate were charged.

[0099] Subsequently, the mixture was heated to 260° C. while stirring, and polymerization was carried out under a nitrogen stream at normal pressure and 260° C. for 5 hours while removing condensed water from the system. During the polymerization, the system was in a uniform molten state.

[0100] After completion of the polymerization, the product was removed, cut and dried to obtain polyamide pellets.

Comparative Example 4

[0101] 51.0 parts by mass of polyoxytetramethylene glycol (PTMG1000) having amino groups instead of the hydroxyl groups at both ends, and having number average molecular weight of 1000, 28.3 parts by mass of terephthalic acid, 20.6 parts by mass of 1,10-decanediamine, and 0.1 parts by mass of sodium hypophosphite monohydrate were charged in a reaction vessel equipped with a heating mechanism and a stirring mechanism, heated to 250° C. with stirring, and polymerization was carried out for 5 hours under a nitrogen stream at normal pressure and 250° C. while releasing generated water vapor. During the polymerization, the system was in suspension.

[0102] After completion of the polymerization, the product was removed, cut and dried, however, the polymerized product was brittle and unsuitable for practical use.

[0103] Tables 1 and 2 show the charging compositions of the polyamides, and Tables 3 and 4 show the characteristics of the obtained polyamides.

TABLE-US-00001 TABLE 1 Example 1 2 3 4 5 6 7 8 9 Production Charging Dicar- Aliphatic group Dimeric acid 26.7  5.4 16.3 31.6 44.0 49.8 — — 34.5 conditions composition boxylic (A1) having 18 or 1,18- — — — — — — — 20.5 — for (part by acid more carbon atoms Octadecanedi- polyamide mass) carboxylic acid (A2) having 12 or Terephthalic acid 23.5 43.8 33.4 18.8  6.9 17.1 32.3 23.2 23.6 less carbon atoms Adipic acid — — — — — — — — — Diamine Aliphatic group Dimer diamine 25.3  5.1 15.4 29.9 41.7 — 50.1 32.1 — (B1) having 18 or 1,18- — — — — — — — — 17.3 more carbon atoms Octadecanediamine (B2) having 12 or 1,10-Decanediamine 24.4 45.6 34.8 19.6 7.3 33.0 17.5 24.1 24.5 less carbon atoms 1,12-Dodecanediamine — — — — — — — — — 1,6-Hexanediamine — — — — — — — — — PTMG1000 having amino groups at both ends — — — — — — — — — Catalyst Sodium hypophosphite monohyddrate  0.1  0.1  0.1  0.1  0.1  0.1  0.1  0.1  0.1

TABLE-US-00002 TABLE 2 Example Comparative Example 10 11 12 13 14 1 2 3 4 Production Charging Dicar- Aliphatic group Dimeric acid 25.6 29.0 48.6 25.5 32.7 —  4.4 51.3 — conditions composition boxylic (A1) having 18 or 1,18- — — — — — — — — — for (part by acid more carbon atoms Octadecanedi- polyamide mass) carboxylic acid (A2) having 12 or Terephthalic acid 21.4 25.5 24.3 — — 49.0 44.7 — 28.3 less carbon atoms Adipic acid — — — 28.0 33.7 — — — — Diamine Aliphatic group Dimer diamine 25.9 27.5 — 24.1 — —  4.2 48.6 — (B1) having 18 or 1,18- — — — — — — — — — more carbon atoms Octadecanediamine (B2) having 12 or 1,10-Decanediamine — — — — — 50.9 46.6 — 20.6 less carbon atoms 1,12-Dodecanediamine 27.0 — — — — — — — — 1,6-Hexanediamine — 17.9 27.0 22.3 33.5 — — — — PTMG1000 having amino groups at both ends — — — — — — — — 51.0 Catalyst Sodium hypophosphite monohyddrate  0.1  0.1  0.1  0.1  0.1  0.1  0.1  0.1  0.1

TABLE-US-00003 TABLE 3 Example 1 2 3 4 5 Polyamide Final composition Dicarboxylic Aliphatic group Dimeric acid 27.0 5.7 16.8 31.7 43.3 characteristics (% by mass of acid (A1) having 18 or 1,18- — — — — — each unit) more carbon Octadecanedi- atoms carboxylic acid (A2) having 12 or Terephthalic acid 20.1 38.7 29.0 15.9 5.8 less carbon atoms Isophthalic acid — — — — — Adipic acid — — — — — Diamine Aliphatic group Dimer diamine 27.1  5.7 16.8 31.8 43.4 (B1) having 18 or 1,18- — — — — — more carbon Octadecanediamine atoms (B2) having 12 or 1,10-Decanediamine 25.8 48.9 37.4 20.6  7.5 less carbon atoms 1,12-Dodecanediamine — — — — — 1,6-Hexanediamine — — — — — PTMG1000 having amino groups — — — — — at both ends Unit formed from (A1) and Total content (% by mass) 54.1 11.4 33.6 63.5 86.7 unit formed from (B1) Mass ratio of contents ((A1)/(B1)) 50/50 50/50 50/50 50/50 50/50 Evaluation Melting point (° C.) 302 (S)  310 (S) 308 (S) 300 (S) 300 (S) MFR (g/min) 10.3 15.5 11.1  9.7  9.0 Tensile strength (MPa) 36   78   59   32   23   Tensile elastic modulus (MPa) 326 (S) 1740 (B) 804 (A) 211 (S) 140 (S) Tensile elongation at break (%) 173 (S)  50 (B) 123 (A) 255 (S) 305 (S) Shore D hardness  60 (S)  78 (B)  65 (A)  51 (S)  39 (S) Example 6 7 8 9 Polyamide Final composition Dicarboxylic Aliphatic group Dimeric acid 50.3 — — 35.0 characteristics (% by mass of acid (A1) having 18 or 1,18- — — 19.9 — each unit) more carbon Octadecanedi- atoms carboxylic acid (A2) having 12 or Terephthalic acid 14.7 27.7 19.9 20.3 less carbon atoms Isophthalic acid — — — — Adipic acid — — — — Diamine Aliphatic group Dimer diamine — 53.8 34.5 — (B1) having 18 or 1,18- — — — 18.6 more carbon Octadecanediamine atoms (B2) having 12 or 1,10-Decanediamine 35.0 18.5 25.7 26.1 less carbon atoms 1,12-Dodecanediamine — — — — 1,6-Hexanediamine — — — — PTMG1000 having amino groups — — — — at both ends Unit formed from (A1) and Total content (% by mass) 50.3 53.8 54.4 53.6 unit formed from (B1) Mass ratio of contents ((A1)/(B1)) 100/0 0/100 37/63 65/35 Evaluation Melting point (° C.) 289 (A) 273 (A)  306 (S)  307 (S) MFR (g/min) 30.2 25.7  8.3 14.4 Tensile strength (MPa) 40   48   58   62   Tensile elastic modulus (MPa) 618 (A) 575 (A) 1590 (B) 1320 (B) Tensile elongation at break (%) 101 (A) 118 (A)  34 (B)  53 (B) Shore D hardness  65 (A)  63 (A)  75 (B)  71 (B)

TABLE-US-00004 TABLE 4 Example 10 11 12 13 14 Polyamide Final composition Dicarboxylic Aliphatic group Dimeric acid 27.2 30.2 50.7 26.2 35.1 characteristics (% by mass of acid (A1) having 18 or 1,18- — — — — — each unit) more carbon Octadecanedi- atoms carboxylic acid (A2) having 12 or Terephthalic acid 18.2 21.7 20.8 — — less carbon atoms Isophthalic acid — — — — — Adipic acid — — — 23.5 28.6 Diamine Aliphatic group Dimer diamine 27.3 29.3 — 26.3 — (B1) having 18 or 1,18-Octadecanediamine — — — — — more carbon atoms (B2) having 12 or 1,10-Decanediamine — — — — — less carbon atoms 1,12-Dodecanediamine 27.3 — — — — 1,6-Hexanediamine — 18.8 28.5 24.0 36.3 PTMG1000 having amino groups — — — — — at both ends Unit formed from (A1) and Total content (% by mass) 54.5 59.5 50.7 52.5 35.1 unit formed from (B1) Mass ratio of contents ((A1)/(B1)) 50/50 51/49 100/0 50/50 100/0 Evaluation Melting point (° C.) 282 (A) 319 (S) 295 (A) 241 (B) 250 (B) MFR (g/min) 13.1 17.5 28.3 36.7 10.6 Tensile strength (MPa) 31   98   50   45   66   Tensile elastic modulus (MPa) 295 (S) 587 (A) 650 (A) 303 (S) 760 (A) Tensile elongation at break (%) 295 (S) 136 (A) 80 (A) 228 (S) 262 (S) Shore D hardness  56 (S)  63 (A)  68 (A)  58 (S)  69 (A) Comparative Example 1 2 3 4 Polyamide Final composition Dicarboxylic Aliphatic group Dimeric acid — 4.6 49.9 — characteristics (% by mass of acid (A1) having 18 or 1,18- — — — — each unit) more carbon Octadecanedi- atoms carboxylic acid (A2) having 12 or Terephthalic acid 43.7 39.7 — 24.0 less carbon atoms Isophthalic acid — — — — Adipic acid — — — — Diamine Aliphatic group Dimer diamine —  4.6 50.1 — (B1) having 18 or 1,18-Octadecanediamine — — — — more carbon atoms (B2) having 12 or 1,10-Decanediamine 56.3 51.1 — 21.7 less carbon atoms 1,12-Dodecanediamine — — — — 1,6-Hexanediamine — — — — PTMG1000 having amino groups — — — 54.3 at both ends Unit formed from (A1) and Total content (% by mass) 0.0 9.2 100.0 54.3 unit formed from (B1) Mass ratio of contents ((A1)/(B1)) 0/0 50/50 50/50 0/0 Evaluation Melting point (° C.)  315 (S)  313 (S) — — MFR (g/min) 10.0 10.2 59.4 — Tensile strength (MPa) 84   80   16   — Tensile elastic modulus (MPa) 2500 (C) 2010 (C) 103 (S) — Tensile elongation at break (%)   7 (C)  23 (C) 454 (S) — Shore D hardness  83 (C)  81 (C)  33 (S) —

[0104] Since the polyamides of the Examples have a total content of 10 to 90% by mass of the unit formed from the aliphatic dicarboxylic acid (A1) having 18 or more carbon atoms and the unit formed from the aliphatic diamine (B1) having 18 or more carbon atoms, all of these each has the excellent flexibility, melting point of 240° C. or higher, and excellent thermal resistance.

[0105] Because the polyamide of Comparative Example 1 did not include any unit formed from (A1) or any unit formed from (B1), and thus did not have any soft segment, and because the polyamide of Comparative Example 2 had a total content of less than 10% by mass of the unit formed from (A1) and the unit formed from (B1), both were inferior in flexibility.

[0106] The polyamide of Comparative Example 3 had no melting point and a low thermal resistance because it had a total content more than 90% by mass of the unit formed from (A1) and the unit formed from (B1).