Two-component polyurethane composition

Abstract

A two-component polyurethane composition including a polyol component and a polyisocyanate component, wherein the polyol component comprises at least one polyester polyol A1 based on dimer fatty acids and/or dimer fatty alcohols having an OH number of 65-350 mg KOH/g, at least one polybutadiene polyol A2 and at least one alkoxylated alkylenediamine A3. The polyurethane composition has high strength and only a minor dependence of the mechanical properties, especially strength, on temperature, especially in the range from −40° C. to +100° C.

Claims

1. A two-component polyurethane composition consisting of a polyol component K1 and a polyisocyanate component K2; wherein the polyol component K1 comprises at least one polyester polyol A1 based on dimer fatty acids and/or dimer fatty alcohols having an OH number of 65-350 mg KOH/g; and at least one polybutadiene polyol having an OH functionality in the range of 2.1-2.9 and an OH number of 40-100 mg KOH/g A2; and at least one alkoxylated alkylenediamine having an OH number of 350-950 mg KOH/g A3; and wherein the polyisocyanate component K2 comprises at least one aromatic polyisocyanate B1, where the ratio of the OH groups of A1:A2 is 1:1-20:1.

2. The two-component polyurethane composition as claimed in claim 1, wherein the at least one polyester polyol A1 is a polyester polyol A1 based on dimer fatty acids derived from C.sub.10-C.sub.26 fatty acids.

3. The two-component polyurethane composition as claimed in claim 1, wherein it is an alkoxylated alkylenediamine having an OH number of 350-950 mg KOH/g A3 selected from the list consisting of N,N,N′,N′-tetrakis(2-hydroxyethyl)ethylenediamine and N,N,N′,N′-tetrakis (2-hydroxypropyl)ethylenediamine.

4. The two-component polyurethane composition as claimed in claim 1, wherein the polyol component K1 additionally includes at least one aliphatic triol A4, where the aliphatic triol A4 is: propane-1,2,3-triol and/or 1,1,1-trimethylolpropane and/or polyether polyols based on 1,1,1-trimethylolpropane having a molecular weight of 170-500 g/mol and an OH number of 400-1100 mg KOH/g.

5. The two-component polyurethane composition as claimed in claim 1, wherein the ratio of the OH groups of A1:A2 is 1:1-8:1.

6. The two-component polyurethane composition as claimed in claim 1, wherein the polyol component K1 optionally includes at least one aliphatic triol A4, where the aliphatic triol A4 is: propane-1,2,3-triol and/or 1,1,1-trimethylolpropane and/or polyether polyols based on 1,1,1-trimethylolpropane having a molecular weight of 170-500 g/mol and an OH number of 400-1100 mg KOH/g, and the ratio of the OH groups of (A1+A2):(A3+A4) is less than or equal to 0.6:1.

7. The two-component polyurethane composition as claimed in claim 1, wherein the ratio of all NCO groups of the aromatic polyisocyanates B1:all OH groups of the polyol component K1=0.9:1-1.2:1.

8. The two-component polyurethane composition as claimed in claim 1, wherein the aromatic polyisocyanate B1 is monomeric MDI or oligomers, polymers and derivatives derived from MDI.

9. The two-component polyurethane composition as claimed in claim 1, wherein the polyol component K1 optionally includes at least one aliphatic triol A4, where the aliphatic triol A4 is: propane-1,2,3-triol and/or 1,1,1-trimethylolpropane and/or polyether polyols based on 1,1,1-trimethylolpropane having a molecular weight of 170-500 g/mol and an OH number of 400-1100 mg KOH/g, and the sum total of all OH groups of (A1+A2+A3A4) is ≥80% of the sum total of all OH groups of the two-component polyurethane composition.

10. A method of bonding a first substrate to a second substrate, comprising the steps of mixing the polyol component K1 and the polyisocyanate component K2 of the two-component polyurethane composition as claimed in claim 1, applying the mixed polyurethane composition to at least one of the substrate surfaces to be bonded, joining the substrates to be bonded within the open time, curing the polyurethane composition.

11. A bonded article obtained from a method as claimed in claim 10.

12. A structural adhesive that bonds two substrates formed by using the two-component polyurethane composition as claimed in 1.

13. A method of filling joins and gaps in a substrate, comprising the steps of a) mixing the polyol component K1 and the polyisocyanate component K2 of the two-component polyurethane composition as claimed in claim 1, b) applying the mixed polyurethane composition to the gap or join to be filled in the substrate, c) curing the polyurethane composition in the join or gap.

14. An article obtained from the method as claimed in claim 13.

15. An infusion resin formed by using the two-component polyurethane composition as claimed in 1.

Description

EXAMPLES

(1) TABLE-US-00002 Substances used: A1 Priplast ® 1837, room temperature liquid polyester diol based on dimer fatty acids of C.sub.14-C.sub.22 fatty acids, dimer acid content of more than 95%, average molecular weight about 1000 g/mol, OH number 110 mg KOH/g (Croda PLC, UK). A1 Priplast ® 1838, room temperature liquid polyester diol Ref. based on dimer fatty acids of C.sub.14-C.sub.22 fatty acids, dimer acid content of more than 95%, average molecular weight about 2000 g/mol, OH number 56 mg KOH/g (Croda PLC, UK). A2 Polybd 45 HTLO, polybutadiene polyol having primary OH groups, OH functionality 2.4-2.6, average molecular weight about 2800 g/mol, OH number 48 mg KOH/g (Total Cray Valley, USA) A3 Quadrol, N,N,N′,N′-tetrakis(2- hydroxypropyl)ethylenediamine, OH number 770 mg KOH/g, Sigma Aldrich A4 Desmophen ® 4011 T, OH number of 550 ± 25 mg KOH/g, molecular weight of about 300 ± 20 g/mol, Bayer MaterialScience, Germany Molecular Molecular sieve, zeolite (Sylosiv ® A3 from W. R. sieve Grace & Co., USA) B1-1 VL Desmodur VL, polymeric MDI, aveage NCO functionality of 2.5, Desmodur ® VL, Covestro AG, Germany B1-2 CD Desmodur CD, modified diphenylmethane diisocyanate containing MDI-carbodiimide adducts, average NCO functionality of 2.2., NCO content 29.4% by weight, Isonate ® M 143 from Dow

(2) Production of Polyurethane Compositions

(3) For each composition, the ingredients specified in tables 1-6 were processed in the specified amounts (in parts by weight) of the polyol component K1 by means of a vacuum dissolver with exclusion of moisture to give a homogeneous paste, and stored. The ingredients of the polyisocyanate component K2 specified in table 1 were likewise processed and stored. The two components were then processed by means of a SpeedMixer® (DAC 150 FV, Hauschild) for 30 seconds to give a homogeneous paste (ratio of all NCO groups B1:all OH groups of the polyol component K1=1.10 in each case), which was immediately tested as follows:

(4) To determine the mechanical properties, the adhesive was converted to dumbbell form according to ISO 527, Part 2, 1B, and stored/cured under standard climatic conditions (23° C., 50% relative humidity) for 7 days. Thereafter, at room temperature, modulus of elasticity in the range from 0.05% to 0.25% elongation (“Modulus of elasticity 1”, “Em 0.05-0.25%”), modulus of elasticity in the range from 0.5% to 5% elongation (“Modulus of elasticity 2”, “Em 0.5-5%”), tensile strength (TS) and elongation at break (EB) of the test specimens thus produced were measured to ISO 527 on a Zwick Z020 tensile tester at a testing speed of 10 mm/min.

(5) Glass transition temperature, abbreviated in the tables to T.sub.g, was determined from DMTA measurements on strip samples (height 2-3 mm, width 2-3 mm, length 8.5 mm) which were stored/cured at 23° C. for 7 days, with a Mettler DMA/SDTA 861e instrument. The measurement conditions were: measurement in tensile mode, excitation frequency 10 Hz and heating rate 5 K/min. The samples were cooled down to −70° C. and heated to 200° C. with determination of the complex modulus of elasticity E* [MPa], and a maximum in the curve for the loss angle “tan δ” was read off as T.sub.g.

(6) The results are reported in tables 1-6.

(7) The progression of the modulus of elasticity (complex modulus of elasticity E* [MPa] as a function of temperature [° C.]) was reproduced in FIGS. 1 and 2 for the compositions identified.

(8) Lap shear strength (LSS) was measured by producing test specimens with the compositions listed in table 7. The adhesive was applied 1 minute after the conclusion of the mixing time in each case between two heptane-degreased carbon fiber-reinforced composite test specimens (Sika Carbodur plates, Sika AG, Switzerland) in a layer thickness of 0.8 mm and over an overlapping bond area of 10×45 mm. The test specimens were stored/cured under standard climatic conditions for 7 days. Lap shear strength was determined to DIN EN 1465 at a strain rate of 10 mm/min at 23° C. (LSS RT), and at 80° C. (LSS 80° C.).

(9) TABLE-US-00003 TABLE 1 Ref.1 Ref.2 Ref.3 E1 Ref.4 E2 E3 E4 E5 E6 Ref.5 K1 A1 Ref. (OHN 56) 20 15 A1 (OHN 110) 20 15 19 14 12 10 8 6 5 A2 (OHN 48) 5 5 5 7 9 11 13 14 A3 (OHN 770) 4 4 4 4 5 5 5 5 5 5 5 A4 (OHN 550) Molecular sieve 1 1 1 1 1 1 1 1 1 1 1 K2 B1-1 VL 11.00 10.90 13.80 13.00 15.53 14.72 14.39 14.08 13.75 13.42 13.26 B1-2 CD GT [min] 6′ 7′ 5′ 4′ 2′ 2′ 2′ 2′ 2′ 1′ 2′ 1st TG [° C.] −20 −27 17 −50 1 −50 −58 −53 −60 −48 −46 2nd TG [° C.] 165 165 103 120 111 130 136 148 157 175 188 TS [MPa] 11.6 9.58 17.7 16.3 22 20.2 20.7 18.6 15.5 7.68 5.03 EB [%] 66.9 67.6 58 61 60.3 68.4 75.3 53.7 28.5 19.8 36.1 Mod. E. 1 [MPa] 38.8 24.1 377 419 615 573 634 613 645 176 31.1 Mod. E. 2 [MPa] 26.51 17.7 191 194 300.27 262.87 275.12 279.97 247.01 86.11 21.14 A1/(A2 + A3 + A4) 0.36 0.25 0.71 0.50 0.54 0.38 0.32 0.26 0.20 0.15 0.12 (A1 + A2)/(A3 + A4) 0.36 0.35 0.71 0.61 0.54 0.46 0.43 0.40 0.37 0.33 0.32 (A1 + A2)/(A3) 0.36 0.35 0.71 0.61 0.54 0.46 0.43 0.40 0.37 0.33 0.32 (A1 + A2)/(A4) — — — — — — — — — — — A1/A2 — 3.5 — 6.88 — 6.42 3.93 2.55 1.67 1.06 0.82 A1/A3 0.36 0.27 0.71 0.54 0.54 0.40 0.34 0.29 0.23 0.17 0.14 Diff.Tg1 + Tg2 185 192 103 170 111 180 194 201 217 223 234

(10) TABLE-US-00004 TABLE 2 Ref.6 E7 Ref.7 E8 E9 E10 E11 E12 Ref.8 K1 A1 Ref. (OHN 56) A1 (OHN 110) 20 15 19 14 12 10 8 6 5 A2 (OHN 48) 5 5 7 9 11 13 14 A3 (OHN 770) 4 4 5 5 5 5 5 5 5 A4 (OHN 550) Molecular sieve 1 1 1 1 1 1 1 1 1 K2 B1-1 VL B1-2 CD 14.80 13.92 16.66 15.77 15.42 15.08 14.73 14.38 14.21 GT [min] 6′ 2′ 3′ 3′ 2′ 3′ 3′ 2′ 1′ 1st TG [° C.] — −57 — −58 −56 −58 −55 −52 −49 2nd TG [° C.] 100 115 118 136 139 151 152 160 168 TS [MPa] 17.2 17.3 22.2 20.1 20 20.7 18.7 11.1 7.16 EB [%] 64.9 71.4 63.6 51.7 44.6 69.5 18.5 15.2 40 Mod. E. 1 [MPa] 451 498 749 690 704.33 726 740 422 61.6 Mod. E. 2 [MPa] 233.41 256.49 385.79 350.78 362.06 381.59 341.67 161.38 34.73 A1/(A2 + A3 + A4) 0.71 0.50 0.54 0.38 0.32 0.26 0.20 0.15 0.12 (A1 + A2)/(A3 + A4) 0.71 0.61 0.54 0.46 0.43 0.40 0.37 0.33 0.32 (A1 + A2)/(A3) 0.71 0.61 0.54 0.46 0.43 0.40 0.37 0.33 0.32 (A1 + A2)/(A4) — — — — — — — — — A1/A2 — 6.88 — 6.42 3.93 2.55 1.67 1.06 0.82 A1/A3 0.71 0.54 0.54 0.40 0.34 0.29 0.23 0.17 0.14 Diff.Tg1 + Tg2 — 172 — 194 195 209 207 212 217

(11) TABLE-US-00005 TABLE 3 Ref. 9 Ref. 10 Ref.11 Ref. 12 Ref. 13 Ref. 14 Ref. 15 Ref. 16 Ref. 17 K1 A1 Ref. (OHN 56) A1 (OHN 110) 20 15 19 14 12 10 8 6 5 A2 (OHN 48) 5 5 7 9 11 13 14 A3 (OHN 770) A4 (OHN 550) 4 4 5 5 5 5 5 5 5 Molecular sieve 1 1 1 1 1 1 1 1 1 K2 B1-1 VL 11.50 10.69 12.65 11.84 11.52 11.20 10.90 10.55 10.39 B1-2 CD GT [min] >120 >120 >120 >120 >120 >120 >120 >120 >120 1st TG [° C.] — −56 −52 −45 −50 −53 −41 −50 −52 2nd TG [° C.] 56 66 75 76 83 72 77 74 75 TS [MPa] 6.59 12.4 10.9 12.8 13.6 12.1 8.7 6.7 6.7 EB [%] 83 135 83 113 113 118 67 59 59 Mod. E. 1 [MPa] 25.2 129 172 190 396 192 267 328 184 Mod. E. 2 [MPa] 20.3 43.7 74.7 95.9 117.7 95.8 94.5 60.4 56.5 A1/(A2 + A3 + A4) 0.71 0.50 0.54 0.38 0.32 0.26 0.20 0.15 0.12 (A1 + A2)/(A3 + A4) 0.71 0.61 0.54 0.46 0.43 0.40 0.37 0.33 0.32 (A1 + A2)/(A3) — — — — — — — — — (A1 + A2)/(A4) 0.71 0.61 0.54 0.46 0.43 0.40 0.37 0.33 0.32 A1/A2 — 6.88 — 6.42 3.93 2.55 1.67 1.06 0.82 A1/A3 — — — — — — — — — Diff.Tg1 + Tg2 — 122 127 121 133 125 118 124 127

(12) TABLE-US-00006 TABLE 4 Ref. 18 Ref. 19 Ref.20 Ref.21 Ref.22 Ref.23 Ref.24 Ref.25 Ref.26 K1 A1 Ref. (OHN 56) A1 (OHN 110) 20 15 19 14 12 10 8 6 5 A2 (OHN 48) 5 5 7 9 11 13 14 A3 (OHN 770) A4 (OHN 550) 4 4 5 5 5 5 5 5 5 Molecular sieve 1 1 1 1 1 1 1 1 1 K2 B1-1 VL B1-2 CD 12.33 11.46 13.56 12.69 12.34 12.00 11.65 11.30 11.13 GT [min] >120 >120 >120 >120 >120 >120 >120 >120 >120 1st TG [° C.] 14 −42 5 −55 −55 −42 −58 −52 −52 2nd TG [° C.] 66 70 74 77 80 88 82 84 90 TS [MPa] 13.1 16.6 14.3 18.1 18.9 16.6 17.1 10.9 8.8 EB [%] 116.6 147.1 89 135.1 150.8 134.9 148 74.2 37 Mod. E. 1 [MPa] 218 286 382 471 427 503 463 440 214 Mod. E. 2 [MPa] 84.9 107.7 162.6 190.4 191.6 199.3 174.9 137.7 104 A1/(A2 + A3 + A4) 0.71 0.50 0.54 0.38 0.32 0.26 0.20 0.15 0.12 (A1 + A2)/(A3 + A4) 0.71 0.61 0.54 0.46 0.43 0.40 0.37 0.33 0.32 (A1 + A2)/(A3) — — — — — — — — — (A1 + A2)/(A4) 0.71 0.61 0.54 0.46 0.43 0.40 0.37 0.33 0.32 A1/A2 — 6.88 — 6.42 3.93 2.55 1.67 1.06 0.82 A1/A3 — — — — — — — — — Diff.Tg1 + Tg2

(13) TABLE-US-00007 TABLE 5 Ref.27 E13 Ref.28 E14 E15 E16 E17 E18 Ref.29 K1 A1 Ref. (OHN 56) A1 (OHN 110) 20 15 19 14 12 10 8 6 5 A2 (OHN 48) 5 5 7 9 11 13 14 A3 (OHN 770) 1.6 1.6 2 2 2 2 2 2 2 A4 (OHN 550) 2.4 2.4 3 3 3 3 3 3 3 Molecular sieve K2 B1-1 VL 12.42 11.61 13.81 12.99 12.67 12.35 12.02 11.70 11.54 B1-2 CD GT [min] 44′ 35′ 25′ 22′ 19′ 17′ 13′ 11′ 9′ 1st TG [° C.] — 0 10 −55 −55 −50 −40 −53 −40 2nd TG [° C.] 71 80 89 84 89 96 105 119 130 TS [MPa] 12.6 13.7 17.17 18 18.2 17.7 14.47 10.5 5.8 EB [%] 79.8 93 80.46 93.7 85.5 74.27 56.9 35.3 20.35 Mod. E. 1 [MPa] 183 197 306 295 368 508 410 301 229 Mod. E. 2 [MPa] 71.63 79.08 145.35 149.06 171.18 182.83 179.8 141.79 78.59 A1/(A2 + A3 + A4) 0.86 0.59 0.66 0.45 0.37 0.30 0.24 0.17 0.14 (A1 + A2)/(A3 + A4) 0.86 0.74 0.66 0.56 0.52 0.48 0.44 0.40 0.38 (A1 + A2)/(A3) 1.79 1.53 1.36 1.16 1.08 0.99 0.91 0.83 0.79 (A1 + A2)/(A4) 1.67 1.43 1.27 1.08 1.00 0.93 0.85 0.78 0.74 A1/A2 — 6.88 — 6.42 3.93 2.55 1.67 1.06 0.82 A1/A3 1.79 1.34 1.36 1.00 0.86 0.71 0.57 0.43 0.36 Diff.Tg1 + Tg2 — 80 79 139 144 146 145 172 170

(14) TABLE-US-00008 TABLE 6 Ref.30 E19 Ref.31 E20 E21 E22 E23 E24 Ref.32 K1 A1 Ref. (OHN 56) A1 (OHN 110) 20 15 19 14 12 10 8 6 5 A2 (OHN 48) 5 5 7 9 11 13 14 A3 (OHN 770) 1.6 1.6 2 2 2 2 2 2 2 A4 (OHN 550) 2.4 2.4 3 3 3 3 3 3 3 Molecular sieve 1 1 1 1 1 1 1 1 1 K2 B1-1 VL B1-2 CD 13.31 12.44 14.79 13.92 13.58 13.23 12.88 12.53 12.35 GT [min] 75′ 60′ 53′ 35′ 25′ 17′ 15′ 13′ 12′ 1st TG [° C.] — −44 — −44 −47 −47 −40 −58 −50 2nd TG [° C.] 78 84 87 97 97 104 112 124 132 TS [MPa] 15.8 16.7 18.7 19.6 18.35 18.6 17.8 13 9.53 EB [%] 94.9 100.4 81.3 101.9 100.15 94.4 96.35 32.3 30.1 Mod. E. 1 [MPa] 316 346 494 530 537 516 488 483 288 Mod. E. 2 [MPa] 144.27 172.37 257.36 259.09 252.3 263.27 261.33 229.35 135.88 A1/(A2 + A3 + A4) 0.86 0.59 0.66 0.45 0.37 0.30 0.24 0.17 0.14 (A1 + A2)/(A3 + A4) 0.86 0.74 0.66 0.56 0.52 0.48 0.44 0.40 0.38 (A1 + A2)/(A3) 1.79 1.53 1.36 1.16 1.08 0.99 0.91 0.83 0.79 (A1 + A2)/(A4) 1.67 1.43 1.27 1.08 1.00 0.93 0.85 0.78 0.74 A1/A2 — 6.88 — 6.42 3.93 2.55 1.67 1.06 0.82 A1/A3 1.79 1.34 1.36 1.00 0.86 0.71 0.57 0.43 0.36 Diff.Tg1 + Tg2 — 128 — 141 144 151 152 182 182

(15) TABLE-US-00009 TABLE 7 Ref. 7 E9 Ref.22 Ref.31 E21 Ref.2 E1 Ref.4 E3 Ref. 5 Ref. 13 Ref.28 E15 K1 A1 Ref. 15 (OHN 56) A1 (OHN 110) 19 12 12 19 12 15 19 12 5 12 19 12 A2 (OHN 48) 7 7 7 5 5 7 14 7 7 A3 (OHN 770) 5 5 2 2 4 4 5 5 5 2 2 A4 (OHN 550) 5 3 3 5 3 3 Molecular sieve 1 1 1 1 1 1 1 1 1 1 1 1 1 K2 B1-1 VL 10.90 13.00 15.53 14.39 13.26 11.52 13.81 12.67 B1-2 CD 16.66 15.42 12.34 14.79 13.58 LSS RT [MPa] 10.2 13.9 11.7 11.6 12.5 6.0 12.6 12.0 13.1 5.6 9.7 11.2 11.6 LSS 80° C. 5.2 5.5 1.6 3.5 5.2 3.5 6.8 5.2 6.2 3.3 1.4 3.4 5.3 [MPa]

(16) Tables 1-7 specify the components of the polyol comp. K1, or of the polyisocyanate comp. K2, in parts by weight. The figures A1/(A2+A3+A4), (A1+A2)/(A3+A4), (A1+A2)/(A3), (A1+A2)/(A4), A1/A2 and A1/A3 relate to the molar ratio of the OH groups.

(17) “Gelation Time (GT) [min]” as a measure of open time was determined the pot life in a beaker. For this purpose, 20 g of the polyol comp. K1 was mixed with the appropriate amount of polyisocyanate comp. K2 for 30 seconds, and the time of occurrence of gelation was determined, i.e. when a thread of the mixed composition on a metal spatula of length 15 cm (spatula scoop 30×10 mm length/width) broke in the course of stirring.

(18) E1 to E24 are inventive examples. Ref.1 to Ref.32 are comparative examples.