PROCESS FOR PRODUCING POLYURETHANE BOOTS

Abstract

Disclosed is a process for producing polyurethane boots. The method includes mixing organic polyisocyanates with a combination of polyols, a chain extender, a blowing agent, a catalyst, and optionally other auxiliaries and/or additives. The resulting reaction mixture is introduced, in only one injection, into a mold including a sole and an upper of the mold and allowed to react to form a polyurethane boot. At least one catalyst including a tertiary amine and sebacic acid is employed in a molar ratio of 1:0.19 to 0.27.

Claims

1. A process for producing a polyurethane boots boot wherein a) organic polyisocyanates are mixed with b) polyols, c) chain extender, d) blowing agent, e) catalyst and f) optionally other auxiliaries and/or additives to afford a reaction mixture and in only one injection introducing the reaction mixture into a mold comprising a sole and an upper of the mold and allowed to react to form the polyurethane boot, wherein at least one catalyst comprising a tertiary amine and sebacic acid is employed in a molar ratio of tertiary amine to sebacic acid of 1:0.19 to 0.27.

2. The process according to claim 1, wherein an MDI is used as polyisocyanate a).

3. The process according to claim 1, wherein a polyesterol (b1) is used as polyol b).

4. The process according to claim 3, wherein the polyester polyol (b1) is obtainable by condensation of aliphatic dicarboxylic acids having 4 to 10 carbon atoms with a difunctional and/or trifunctional aliphatic alcohol.

5. The process according to claim 3, wherein as tertiary amine e) triethylenediamine is employed in an amount of 0.3% to 0.5% by weight based on the components b) to f).

6. The process according to claim 1, wherein a polyetherol (b2) is used as polyol b).

7. The process according to claim 6, characterized in that a propylene glycol-started and/or glycerol-started polyetherol is employed as polyetherol (b2).

8. The process according to claim 6, wherein as tertiary amine e) triethylenediamine and pentamethyldipropylenetriamine is employed in an amount of 0.8% to 1.2% by weight based on the components b) to f).

9. The process according to claim 1, wherein water is employed as the blowing agent.

10. A polyurethane boot obtainable by a process according to claim 1.

11. The polyurethane boot according to claim 10, wherein the boot is a polyurethane integral foam having a density of 150 to 950 g/L.

Description

EXAMPLE 1 (polyesterol (b1)-based)

[0070] The following compounds were employed: [0071] Iso a-1: isocyanate prepolymer from BASF based on 4.4-MDI, modified isocyanates and a mixture of polyesterols having a functionality of 2 and an OH number of 56 mg KOH/g with diethyl oxalate as an additive [0072] Polyesterol (b1-1): polyesterol based on adipic acid, monoethylene glycol and diethylene glycol having an OH number of 56 mg KOH/g [0073] KV c-1: monoethylene glycol [0074] Cat e1-1: triethylenediamine in monoethylene glycol (33% by weight) [0075] Cat e2-1: triethylenediamine (25.5% by weight) in ethylene glycol (59% by weight), sebacic acid (13.5% by weight) and water (2% by weight) [0076] Cat e2-2: triethylenediamine (33.7% by weight) in ethylene glycol (50.8% by weight), sebacic acid (13.5% by weight) and water (2% by weight) [0077] Cat e2-3: triethylenediamine (19.5% by weight) in ethylene glycol (65.0% by weight), sebacic acid (13.5% by weight) and water (2% by weight) [0078] Additive f-1: polysiloxane silicone

TABLE-US-00001 TABLE 1 VB1-1 B1-2 B1-3 B1-4 B1-5 B1-6 B1-7 Polyol b1-1 91.97 91.97 91.97 91.97 91.97 91.97 91.97 KVc-1 5.50 5.50 5.50 5.50 5.50 5.50 5.50 Cat e1-1 0.50 0.50 0.50 0.50 0.20 0.20 0.20 Cat e2-1 0.00 0.56 1.06 1.36 0.90 Cat e2-2 0.90 Cat e2-3 0.90 Amine/sebacic 1:0 1:0.13 1:0.18 1:0.20 1:0.23 1:0.18 1:0.28 acid molar ratio % by wt Amine* 0.16 0.31 0.43 0.51 0.30 0.37 0.25 Additive f-1 0.28 0.28 0.28 0.28 0.28 0.28 0.28 Water 0.26 0.26 0.26 0.26 0.26 0.26 0.26 MR to Iso a-1 100/69.9 100/72.1 100/74.1 100/75.3 100/72.3 100/71.8 100/72.6 *based on the components (b) to (f)

TABLE-US-00002 TABLE 2 Property VB1-1 B1-2 B1-3 B1-4 B1-5 B1-6 B1-7 Cream time [s] 24 40 20 12 19 15 24 Fiber time [s] 71 103 60 35 54 44 65 Rise time [s] >280 >240 230 120 160 143 224 Apparent density 390 320 296 338 370 373 375 [g/L] Flex time [min] >8 7:30 >7 4:15 6:30 6:00 >8 Demolding time 6 6 6 6 6 6 6 [min] Density [g/l] 689 622 667 678 674 686 664

[0079] The best results in a polyesterol (b1)-based boot were achieved using polyurethane systems having a molar ratio of tertiary amine (e1) to sebacic acid (e2) of 1:0.19 to 0.27. This resulted in sufficient time to fill the boot (cream time more than 15 s) while the systems simultaneously achieved sensible fiber, rise and flex times (less than 7 min). It has also proved advantageous to employ the tertiary amine catalyst in a concentration of 0.3% to 0.5% by weight based on the components (b) to (f).

EXAMPLE 2 (polyetherol (b2)-based)

[0080] The following compounds were employed: [0081] Iso a-2: isocyanate prepolymer from BASF based on 4.4-MDI, modified isocyanates and a mixture of polyetherols having a functionality of 2 and an OH number of 29.5 mg KOH/g with dipropylene glycol as an additive [0082] Polyetherol (b2-1): Propylene glycol-started polyether polyol having an OH number of 29.5 and predominantly primary OH groups (composition 81.1% by weight propylene oxide, 18.5% by weight ethylene oxide with an OH number of 29.5 mg KOH/g) [0083] Polyetherol (b2-2): Glycerol-started polyether polyol having an OH number of 35 and predominantly primary OH groups (composition 84.4% by weight propylene oxide, 13.3% by weight ethylene oxide with an OH number of 35 mg KOH/g) [0084] KV c-2: 1,4-butanediol [0085] Cat e1-2: pentamethyldipropylenetriamine [0086] Cat e2-1: triethylenediamine (25.5% by weight) in ethylene glycol (59% by weight), sebacic acid (13.5% by weight) and water (2% by weight) [0087] Cat e2-2: triethylenediamine (33.7% by weight) in ethylene glycol (50.8% by weight), sebacic acid (13.5% by weight) and water (2% by weight) [0088] Cat e2-3: triethylenediamine (19.5% by weight) in ethylene glycol (65.0% by weight), sebacic acid (13.5% by weight) and water (2% by weight) [0089] Cat e3-1: dimethyltin carboxylate [0090] Additive f-1: polysiloxane silicone

TABLE-US-00003 TABLE 3 % by weight B2-1 B2-2 B2-3 B2-4 B2-5 B2-6 B2-7 Polyol b2-1 42.00 42.00 42.00 42.00 42.00 42.00 42.00 Polyol b2-2 46.02 46.02 46.02 46.02 46.02 46.02 46.02 KV c-2 9.00 9.00 9.00 9.00 9.00 9.00 9.00 Cat e1-2 0.30 0.30 0.30 0.30 0.30 0.50 0.70 Cat e2-1 2.00 2.20 2.40 2.40 2.40 Cat e2-2 2.40 Cat e2-3 2.40 Cat e3-1 0.03 0.03 0.03 0.03 0.03 0.03 0.03 Amine/sebacic 1:0.20 1:0.22 1:0.23 1:0.18 1:0.28 1:0.20 1:0.18 acid molar ratio % by wt Amine* 0.8 0.86 0.91 1.20 0.77 1.1 1.3 Additive f-1 0.30 0.30 0.30 0.30 0.30 0.30 0.30 Water 0.35 0.35 0.35 0.35 0.35 0.35 0.35 MR to Iso a-2 100/92 100/88 100/90 100/94 100/99 100/96 100/96 *based on the components (b) to (f)

TABLE-US-00004 TABLE 4 Property B2-1 B2-2 B2-3 B2-4 B2-5 B2-6 B2-7 Cream time [s] 20 18 17 15 23 16 16 Fiber time [s] 47 49 48 45 61 46 45 Rise time [s] 101 104 101 90 120 95 98 Apparent density 472 454 432 421 443 408 398 [g/L] Flex time [min] 5:30 5:30 4:30 4:15 6:00 4:15 4:15 Demolding time 6 6 6 6 6 6 6 [min] Density [g/l] 704 693 699 703 687 680 689

[0091] The best results in a polyetherol (b2)-based boot were achieved using polyurethane systems having a molar ratio of tertiary amine (e1) to sebacic acid (e2) of 1:0.19 to 0.27. This resulted in sufficient time to fill the boot (cream time more than 15 s) while the systems simultaneously achieved sensible fiber, rise and flex times (less than 6 min). It has also proved advantageous to employ the tertiary amine catalyst (e1) in a concentration of 0.8% to 1.2% by weight based on the components (b) to (f).