BIO-BASED AMINE CURING AGENT FOR CURABLE COMPOSITIONS

Abstract

The use of a hardener containing at least one amine of formula (I) for crosslinking of amine-reactive compounds, wherein the amines of formula (I) are biobased and obtainable from vanillin or guaiacol. The amines of formula (I) have particularly good compatibility with epoxy resins as the amine-reactive compound. They make it possible to obtain biobased epoxy resin products that are superior to petrobased products not only in terms of sustainability but also in terms of technical performance.

Claims

1. A method comprising: forming a hardener composition by adding to a hardener at least one amine of formula (I) ##STR00025## where ##STR00026## is a benzene ring or cyclohexane ring, R.sup.1 is H or an alkyl radical having 1 to 6 carbon atoms, R.sup.2 is H or a monovalent organic radical having 1 to 6 carbon atoms or an aminoalkyl radical having 2 to 10 carbon atoms or an N-substituted aminoalkyl radical having 2 to 10 carbon atoms and R.sup.3 is H or methyl; and mixing the hardener composition with an amine-reactive compound such that a crosslinking reaction occurs.

2. The method as claimed in claim 1, wherein the amine-reactive compound is an epoxy resin, polyisocyanate, poly(meth)acrylate, a polycarboxylic acid or a carboxylic anhydride.

3. The method as claimed in claim 1, wherein the amine-reactive compound is an epoxy resin.

4. The method as claimed in claim 1, wherein R.sup.1 is methyl.

5. The method as claimed in claim 4, wherein R.sup.2 and R.sup.3 are both H.

6. The method as claimed in claim 4, wherein R.sup.3 is H and R.sup.2 is a monovalent organic radical having 1 to 6 carbon atoms.

7. The method as claimed in claim 6, wherein R.sup.2 is furfuryl or tetrahydrofuryl.

8. The method as claimed in claim 1, wherein R.sup.1 is H and ##STR00027## is a benzene ring.

9. The method as claimed in claim 8, wherein R.sup.2 and R.sup.3 are both methyl.

10. The method as claimed in claim 8, wherein R.sup.2 is furfuryl and R.sup.3 is H.

11. The method as claimed in claim 1, wherein R.sup.3 is H and R.sup.2 is a linear aminoalkyl radical having 2 to 6 carbon atoms.

12. The method as claimed in claim 1, wherein R.sup.3 is H and R.sup.2 is an N-substituted aminoalkyl radical having 2 to 10 carbon atoms.

13. The method as claimed in claim 1, wherein in the amine of formula (I) the radicals R.sup.2 on the two nitrogen atoms are in each case different radicals.

14. The method as claimed in claim 3, wherein the hardener contains at least one further constituent selected from further amines not conforming to formula (I), accelerators and diluents.

15. An epoxy resin composition comprising a resin component comprising at least one epoxy resin and a hardener component comprising the hardener as described in claim 4.

16. A cured epoxy resin composition obtained from the epoxy resin composition as claimed in claim 15 after the mixing of the resin component and the hardener component.

17. A hardener for crosslinking amine-reactive compounds, the hardener containing at least one amine of formula (I) ##STR00028## where ##STR00029## is a benzene ring or cyclohexane ring, R.sup.1 is H or an alkyl radical having 1 to 6 carbon atoms, R.sup.2 is H or a monovalent organic radical having 1 to 6 carbon atoms or an aminoalkyl radical having 2 to 10 carbon atoms or an N-substituted aminoalkyl radical having 2 to 10 carbon atoms and R.sup.3 is H or methyl.

18. The hardener as claimed in claim 17, wherein the amine-reactive compound is an epoxy resin, polyisocyanate, poly(meth)acrylate, a polycarboxylic acid or a carboxylic anhydride.

19. The hardener as claimed in claim 17, wherein the amine-reactive compound is an epoxy resin

20. The hardener as claimed in claim 17, wherein R.sup.1 is methyl.

Description

EXAMPLES

[0213] The following are exemplary embodiments which are intended to more particularly elucidate the described invention. It goes without saying that the invention is not limited to these described exemplary embodiments.

[0214] AHEW stands for amine hydrogen equivalent weight.

[0215] EEW stands for epoxy equivalent weight.

[0216] Standard climatic conditions (SCC) refer to a temperature of 231 C. and a relative atmospheric humidity of 505%.

[0217] The chemicals used were from Sigma-Aldrich Chemie GmbH, unless otherwise stated.

[0218] Description of the measurement methods: Gas chromatograms (GC) were measured in the temperature range from 60 C. to 320 C. with a heating rate of 15 C./min and a 10 min hold time at 320 C. The injector temperature was 250 C. A Zebron ZB-5 column was used (L=30 m, ID=0.25 mm, dj=0.5 m) at a gas flow of 1.5 ml/min. Detection was by flame ionization (FID).

[0219] Infrared spectra (FT-IR) were measured as undiluted films on a Nicolet iS5 FT-IR instrument from Thermo Scientific equipped with a horizontal ATR measurement unit with a diamond crystal. Absorption bands are reported in wavenumbers (cm-1).

[0220] .sup.1H and .sup.13C NMR spectra were measured at room temperature on a spectrometer of the Bruker Ascend type at 400.14 MHz (1H) or 100.63 MHZ (13C); the chemical shifts are reported in ppm relative to tetramethylsilane (TMS). Coupling constants J are reported in Hz. No distinction was made between true coupling and pseudo-coupling patterns.

[0221] Viscosity was measured on a thermostated Rheotec RC30 cone-plate viscometer (cone diameter 50 mm, cone angle 1, cone tip-plate distance 0.05 mm, shear rate 10 s-1).

[0222] Amine value was determined by titration (with 0.1 N HCIO4 in acetic acid against crystal violet).

Substances and Abbreviations Used:

[0223]

TABLE-US-00001 Vanillin EuroVanillin Supreme, RCI = 1 (Borregaard) Araldite Bisphenol A diglycidyl ether, EEW approx. 187 g/eq GY 250 (Huntsman) Araldite Monoglycidyl ethers of C.sub.12 to C.sub.14 alcohols, EEW DY-E about 290 g/eq (Huntsman) MXDA 1,3-bis(aminomethyl)benzene, AHEW 34 g/eq (Mitsubishi Gas Chemical) Dibenzyl N, N-dibenzyl-1,3-bis(aminomethyl)benzene, AHEW MXDA about 158.2 g/eq, produced by reductive alkylation of MXDA and benzaldehyde in a molar ratio of 1:2 Diethylhexyl N, N-bis(2-ethylhexyl)-1,3-bis(aminomethyl)benzene, MXDA AHEW about 180.3 g/eq, produced by reductive alkylation of MXDA and 2-ethylhexanal in a molar ratio of 1:2 B-EDA N-benzyl-1,2-ethanediamine, AHEW 50.1, produced by reductive alkylation of 1,2-ethanediamine and benzaldehyde in a molar ratio of 3:1 and subsequent purification by distillation Ancamine 2,4,6-tris(dimethylaminomethyl)phenol (Evonik) K54

Production of Dialdehydes:

[0224] 4-hydroxy-5-methoxyisophthalaldehyde (=5-formylvanillin) In a round-bottom flask 100.61 g (0.661 mol) of vanillin (4-hydroxy-3-methoxybenzaldehyde) and 110.96 g (0.791 mol) of hexamethylenetetramine (1,3,5,7-tetraazaadamantane) were initially charged under a nitrogen atmosphere and admixed with 500 ml of trifluoroacetic acid. The reaction mixture was boiled under reflux at about 125 C. for 5 h with stirring. 800 ml of aqueous HCl (4 M) were then added and the mixture was boiled under reflux at about 125 C. for a further hour and the reaction mixture was then cooled to room temperature and extracted with altogether 600 ml of dichloromethane. The combined organic phase was dried over magnesium sulfate and concentrated by rotary evaporator and the obtained solid residue was recrystallized from toluene and dried under vacuum. 98.15 g (0.54 mol) of a yellowish powder having a purity of >99% determined by GC (in ethyl acetate) (retention time 11.12 min) were obtained. .sup.1H-NMR (DMSO-d6): 11.30 (br s, 1H, ArOH), 10.36 (s, 1H, OCH 3-position), 9.89 (s, 1H, OCH 1-position), 7.88 (d, 1H, ArH, J=1.8), 7.61 (d, 1H, ArH, J=1.8), 3.96 (s, 3H, OCH.sub.3).

[0225] .sup.13C NMR (CDCl.sub.3): 55.46 (OCH.sub.3), 113.26 (ArCH), 119.00 (ArCH), 128.08 (ArCCHO 3-position), 128.46 ArCCHO 1-position), 148.42 (ArCOCH.sub.3), 156.09 (ArCOH), 188.56 (CHO 3-position), 194.83 (CHO 1-position)

[0226] FT-IR: 3073, 3032, 2991, 2939, 2873, 2733, 2508, 2559, 1683, 1640, 1615, 1588, 1557, 1538, 1502, 1467, 1453, 1435, 1407, 1385, 1323, 1293, 1276, 1200, 1183, 1145, 1090, 1029, 1015, 982, 956, 908, 883, 830, 809, 797, 763, 732, 666.

4,5-Dimethoxyisophthalaldehyde

[0227] In a round-bottom flask 5.01 g (27.8 mmol) of 4-hydroxy-5-methoxyisophthalaldehyde (produced as described above) were initially charged under a nitrogen atmosphere, dissolved in 130 ml of dimethylformamide, admixed with 11.53 g of potassium carbonate and 0.46 g of tetrabutylammonium iodide and stirred at room temperature for 2 h. Subsequently, 8.09 g (55.6 mmol) of dimethyl sulfate were added slowly and the reaction mixture stirred at room temperature for 24 h. Then, 40 ml of aqueous sodium hydroxide solution (1 M) were added, the reaction mixture was concentrated by rotary evaporator and the obtained solid was dissolved in water and extracted with 300 ml of ethyl acetate. The combined organic phase was dried over magnesium sulfate, concentrated by rotary evaporator and dried under vacuum. 5.61 g (26.7 mmol) of a yellowish powder having a purity of >99% determined by GC in ethyl acetate (retention time 11.49 min) were obtained.

[0228] .sup.1H NMR (CDCl.sub.3): 10.38 (s, 1H, OCH 3-position), 9.87 (s, 1H, OCH 1-position), 7.86 (d, 1H, ArH, J=1.92), 7.59 (d, 1H, ArH, J=1.92), 4.05 (s, 3H, OCH.sub.3), 3.91 (s, 3H, OCH.sub.3).

[0229] .sup.13C NMR (CDCl.sub.3): 55.24 (OCH.sub.3), 61.35 (OCH.sub.3), 113.26 (ArCH), 123.42 (ArCH), 128.42 (ArCCHO 3-position), 131.13 (ArCCHO 1-position), 152.64 (ArCO), 156.49 (ArCO), 188.02 (CHO 3-position), 189.46 (CHO 1-position).

[0230] FT-IR: 3020, 2954, 2873, 2849, 1682, 1597, 1581, 1516, 1485, 1463, 1428, 1386, 1335, 1284, 1248, 1227, 1190, 1133, 1071, 1009, 982, 934, 891, 873, 786, 764, 751.

Preparation of Amines of the Formula (I):

Amine A1:1,3-Bis(Aminomethyl)-4,5-Dimethoxybenzene

[0231] In a round-bottom flask 49.22 g (0.6 mol) of sodium acetate and 29.09 g (0.44 mol) of aqueous hydroxylamine (50% by weight in water) were dissolved in 500 ml of water under a nitrogen atmosphere. Subsequently, 38.38 g (0.2 mol) of 4,5-dimethoxyisophthalaldehyde (produced as described above) were added and the reaction mixture was boiled under reflux at about 110 C. for 1.5 h, cooled in an ice bath and the white precipitate filtered off, washed with 300 ml ice-cold water and dried under vacuum. This afforded 35.54 g (0.16 mol) of 4.5-dimethoxyisophthalaldehyde dioxime as a white crystalline powder. 20 g (0.089 mol) thereof were dissolved in a mixture of 100 ml of ethanol and 1200 ml of 1,4-dioxane in a round-bottom flask and hydrogenated in a continuous hydrogenation apparatus with a Raney nickel fixed bed catalyst at a hydrogen pressure of 80 bar, a temperature of 80 C. and a flow rate of 5 ml/min. The reaction was monitored by using IR spectroscopy to check whether the CN band at about 1665 cm-1 had disappeared. The hydrogenated solution was then concentrated by rotary evaporator at 65 C. This afforded 16.12 g (0.086 mol) of a yellowish liquid having an amine number of 519 mg KOH/g, a theoretical AHEW of about 49.1 g/eq, an RCI of 0.8, a viscosity at 20 C. of 277 mPa's and a content of 1,3-bis(aminomethyl)-4,5-dimethoxybenzene determined by GC in ethyl acetate of about 92% (retention time 14.59 min).

[0232] .sup.1H-NMR (DMSO-d6): 6.92 (s, 1H, ArH), 6.90 (s, 1H, ArH), 3.79 (s, 3H, OCH.sub.3), 3.70 (s, 3H, OCH.sub.3), 3.67 (s, 2H, CH.sub.2N), 3.66 (s, 2H, CH.sub.2N), 1.81 (br s, 4H, 2x NH.sub.2).

[0233] .sup.13C-NMR (DMSO-d6): 41.04 (CH.sub.2N), 46.22 (CH.sub.2N), 56.00 (OCH.sub.3), 60.48 (OCH.sub.3), 110.32 (ArCH), 119.02 (ArCH), 137.31 (ArCCH.sub.2), 140.33 (ArCCH.sub.2), 144.89 (ArCO), 152.30 (ArCO).

[0234] FT-IR: 3367, 3284, 3189, 2994, 2932, 2831, 1588, 1488, 1462, 1428, 1383, 1338, 1309, 1225, 1185, 1139, 1080, 1051, 1005, 838, 775, 741, 706.

Amine A2:1,3-Bis(Furfurylaminomethyl)-4,5-Dimethoxybenzene

[0235] In a round-bottom flask 10.0 g (51.5 mmol) of 4,5-dimethoxyisophthalaldehyde (produced as described above) were dissolved in 400 ml of isopropyl alcohol, 10.5 g (10.8 mmol) of furfurylamine were slowly added with stirring and the mixture was stirred at room temperature for a further 30 min. The reaction mixture was was then hydrogenated in a continuous hydrogenation apparatus with a Raney nickel fixed bed catalyst at a hydrogen pressure of 70 bar, a temperature of 70 C. and a flow rate of 5 ml/min. The reaction was monitored by using IR spectroscopy to check whether the CN band at about 1665 cm-1 had disappeared. The hydrogenated solution was then concentrated by rotary evaporator at 65 C. This afforded 16.4 g of a clear, yellow liquid having an amine number of 297 mg KOH/g, a theoretical AHEW of about 178.2 g/eq, an RCI of 0.9, a viscosity at 20 C. of 910 mPa's and a content of 1,3-bis(furfurylaminomethyl)-4,5-dimethoxybenzene determined by GC of about 88.4% (retention time 18.96 min) and about 11.6% byproduct (retention time 19.26 min).

[0236] FT-IR: 3324, 2935, 2867, 2834, 1589, 1488, 1455, 1428, 1359, 1310, 1227, 1180, 1145, 1067, 1008, 919, 847, 776.

Amine A3:2,4-Bis(Dimethylaminomethyl)-6-Methoxyphenol

[0237] In a round-bottom flask 10 g (55 mmol) of 4-hydroxy-5-methoxyisophthalaldehyde (=5-formylvanillin produced as described above), 60 g (120 mmol) of dimethylamine solution (2M in tetrahydrofuran) and 150 ml of tetrahydrofuran were initially charged and cooled with ice water. An orange-red coloring was formed. 35 g of sodium triacetoxyborohydride were then added and the reaction mixture was stirred for 1 h with ice water cooling, then for 1 h at room temperature and then for 1 h at 40 C., whereupon the reaction mixture showed a yellowish coloring. The reaction mixture was then admixed with 75 ml of a potassium carbonate solution (15% by weight in water) and stirred at room temperature for 30 min, whereupon the reaction mixture became almost colorless. Then the reaction mixture was concentrated by rotary evaporator at 80 C., the residue was taken up in tetrahydrofuran, the undissolved potassium carbonate was filtered off and the filtrate was concentrated by rotary evaporator at 65 C. This afforded 12.4 g of an orange oil which was subjected to vacuum distillation at 107 C. to 120 C. and 250 mbar to afford 7.5 g of a yellowish oil having an amine number of 467 mg KOH/g. .sup.1H NMR (CDCl.sub.3): 6.77 (d, 1H, ArH), 6.52 (d, 1H, ArH), 3.87 (t, 3H, OCH.sub.3), 3.62 (t, 2H, CH.sub.2N), 3.32 (t, 2H, CH.sub.2N), 2.32 (t, 6H, (CH.sub.3) 2N), 2.23 (t, 6H, (CH.sub.3) 2N).

Amine A4: Amine Mixture Containing 2,4-Bis(Dimethylaminomethyl)-6-Methoxyphenol

[0238] In a round-bottom flask 24.83 g (0.2 mol) of guaiacol, 81.96 g (0.6 mol) of dimethylamine solution (33% by weight in ethanol) were initially charged in 250 ml of ethanol and admixed with 18.20 g (0.6 mol) of paraformaldehyde. The reaction mixture was heated under reflux for 10 h, then freed of volatile constituents at 65 C. under vacuum by rotary evaporator and then subjected to vacuum distillation at 120 C. to collect 25.6 g of distillate at a vapor temperature of about 100 C. and 0.005 bar. This afforded 45.3 g of distillate as a yellowish clear liquid having an amine number of 452 mg KOH/g. According to 1H-NMR the content of 2,4-bis(dimethylaminomethyl)-6-methoxyphenol was about 89% and the main byproduct present was 2 (4)-dimethylaminomethyl-6-methoxyphenol.

[0239] .sup.1H NMR (CDCl.sub.3): 6.75 (d, 1H, ArH), 6.57 (d, 1H, ArH), 3.74 (s, 3H, OCH.sub.3), 3.53 (s, 2H, CH.sub.2N), 3.24 (s, 2H, CH.sub.2N), 2.21 (s, 6H, (CH.sub.3) 2N), 2.11 (2, 6H, (CH.sub.3) 2N).

Production of Epoxy Resin Adhesives:

Examples 1 and 2

[0240] The resin component employed was Sikadur-42 HE component A (reactive diluent-diluted bisphenol A diglycidyl ether, EEW 175.5 g/eq, Sika) in the amount specified in table 1 (in parts by weight).

[0241] The hardener component employed was the amine specified in table 1 in the specified amount (in parts by weight).

[0242] Subsequently the two components for each example were mixed using a centrifugal mixer (SpeedMixer DAC 150, FlackTek Inc.) and immediately tested as follows:

[0243] Viscosity was measured as described at a temperature of 20 C. 5 min after mixing the resin component and the hardener component.

[0244] Gel time was determined by touching the surface of a freshly mixed amount of about 3 g with an LDPE pipette at regular intervals under standard climatic conditions until no residue remained on the pipette.

[0245] Mechanical properties were determined by applying and curing the mixed adhesive in a silicone mold under standard climatic conditions to afford dumbbell-shaped bars having a thickness of 2 mm and a length of 75 mm at a gage length of 30 mm and a gage width of 4 mm. The tensile bars were removed from the mold after 1 d under standard climatic conditions and after altogether 7 d of curing time under standard climatic conditions used to measure tensile strength, elongation at break and modulus of elasticity (0.05-0.25% elongation) according to EN ISO 527 at a strain rate of 10 mm/min. These results are marked SCC. Further of these tensile bars were removed from the mold after 1 d under standard climatic conditions, and then subjected to further curing at 120 C. in a recirculating oven for 1 d and stored under standard climatic conditions for 1 d before the mechanical properties were determined. These results are marked 120 C.. Further of these tensile bars were removed from the mold after 1 d under standard climatic conditions, and then subjected to further curing at 120 C. in a recirculating oven for 1 d, then stored in water at room temperature for 5 days and then patted dry with a hygiene towel and stored under standard climatic conditions for 1 d before the mechanical properties were determined. These results are marked H.sub.2O. The Tg value (glass transition temperature) was determined by DMTA measurements on cylindrical specimens (height 2 mm, diameter 10 mm) stored as described for tensile strength with a Mettler DMA/SDTA 861e instrument measuring in shear mode with a 10 Hz excitation frequency and a 5 K/min heating rate. The samples were cooled to 70 C. and heated to 200 C. while determining the complex modulus of elasticity M*[MPa], wherein a maximum in the curve for the loss angle tan 0 was read off as the Tg value.

[0246] The results are reported in table 1.

[0247] Comparative examples are marked (Ref.).

TABLE-US-00002 TABLE 1 Composition and properties of examples 1 and 2. 2 Example 1 (Ref.) Resin component: Sikadur-42 HE component A 175.5 175.5 Hardener component: Amine A1 .sup.1 49.1 MXDA 34.0 Viscosity (5) [Pa .Math. s] 1.47 0.74 Gel time 1.5 h >4 h Tensile SCC 46.7 58.1 strength [MPa] 120 C. 72.9 68.0 H.sub.2O 66.0 66.3 Elongation SCC 1.6 2.3 at break 120 C. 7.7 6.8 H.sub.2O 6.2 6.1 Modulus of SCC 3320 3160 elasticity [MPa] 120 C. 3120 2995 H.sub.2O 2980 3070 Tg [C] SCC 62 58 120 C. 88 84 H.sub.2O 82 82 .sup.1 produced as described above

Production of Epoxy Resin Coatings:

Examples 3 to 10

[0248] For each example, the ingredients of the resin component specified in tables 2 and 3 were mixed in the specified amounts (in parts by weight) using the centrifugal mixer and stored with exclusion of moisture.

[0249] The ingredients of the hardener component specified in tables 2 and 3 were likewise processed and stored.

[0250] Subsequently the two components for each example were mixed using the centrifugal mixer and immediately tested as follows: Viscosity and gel time were determined as described for example 1.

[0251] Shore D hardness was determined according to DIN 53505 on two cylindrical test specimens (diameter 20 mm, thickness 5 mm), wherein one was stored under standard climatic conditions and the other at 8 C. and 80% relative humidity and hardness was in each case measured after 1 d and after 2 d.

[0252] In addition, a film was applied to a glass plate in a layer thickness of 500 m, and this was stored/cured under standard climatic conditions. Knig hardness (Knig pendulum hardness according to DIN EN ISO 1522) was determined on this film after 1 d, 2 d, 7 d and after 14 d (1 d SCC), (2 d SCC), (7 d SCC), (14 d SCC). After 14 d the appearance (SCC) of the film was assessed. A clear film was described as attractive if it had a glossy and nontacky surface with no structure.

[0253] Structure refers to any kind of marking or pattern on the surface. A further film was applied to a glass plate in a layer thickness of 500 m and, immediately after application, stored/cured at 8 C. and 80% relative humidity for 7 d and then under standard climatic conditions for 2 weeks. 24 hours after application, a polypropylene bottle top beneath which a moist sponge had been positioned was placed on the film. After a further 24 hours, the sponge and the bottle top were removed and positioned at a new point on the film, from which they were in turn removed and repositioned after 24 hours, which was done 4 times in total. The appearance of this film was then assessed (referred to as appearance (8/80%) in the tables) in the same way as described for appearance (SCC). The number and nature of visible marks that had formed in the film as a result of the moist sponge were also reported in each case. The number of white discolored spots was reported as marks. A faint white discolored spot was designated as (1). A clear white discolored spot was designated as 1. The films cured in this way in turn had their Konig hardness determined, in each case after 7 days at 8 C. and 80% relative humidity (Knig (7d 8/80%)), then after a further 2 days under SCC(Knig (+2d SCC)) or 7 days under SCC(Knig (+7d SCC)) or 14 days under SCC(Knig (+14d SCC)).

[0254] The results are reported in Tables 2 and 3.

[0255] Comparative examples are labelled (Ref.).

TABLE-US-00003 TABLE 2 Composition and properties of examples 3 to 7. 3 6 7 Example (Ref.) 4 5 5a (Ref.) (Ref.) Resin component: Araldite GY-250 167.2 167.2 167.2 167.2 167.2 167.2 Araldite DY-E 31.8 31.8 31.8 31.8 31.8 31.8 Hardener MXDA 34.0 component: Amine A1 1 49.1 Amine A3 1 2.0 Amine A4 1 2.0 B-EDA 50.1 50.1 50.1 50.1 Ancamine K54 2.0 Viscosity (5) [Pa .Math. s] n.d. n.d. 0.24 0.22 0.22 0.23 Gel time n.d. n.d. 5 h 5 h 5 h 5 h Shore D (1 d SCC) n.d. n.d. 72 78 68 60 (2 d SCC) 77 79 71 62 Shore D (1 d 8/80%) n.d. n.d. n.m..sup.2 n.m..sup.2 n.m..sup.2 n.m..sup.2 (2 d 8/80%) 55 58 76 79 Knig (1 d SCC) 11 74 164 91 116 52 [s] (2 d SCC) 13 148 183 141 157 131 (7 d SCC) 16 167 190 188 206 142 (14 d SCC) 22 167 205 190 208 145 Appearance (SCC) cloudy, slight attracttive attractive attractive attractive slightly structure tacky Knig (7 d 8/80%) n.m..sup.3 39 45 36 55 31 [s] (+2 d SCC) n.d. n.d. 134 99 101 63 (+7 d SCC) n.d. n.d. 188 145 143 123 (+14 d SCC) n.m..sup.3 76 188 147 174 169 Appearance (8/80%) cloudy, slightly attractive attractive attractive attractive tacky cloudy Marks 4 4 (1) (1) (1) (1) .sup.1 produced as described above .sup.2not measurable (too soft) .sup.3not measurable (tacky) n.d. stands for not determined

TABLE-US-00004 TABLE 3 Composition and properties of examples 8 to 10. 9 10 Example 8 (Ref.) (Ref.) Resin component: Araldite GY-250 187.0 187.0 187.0 Hardener component: Amine A2 .sup.1 178.2 Dibenzyl MXDA 158.2 Diethylhexyl MXDA 180.3 Viscosity (5) [Pa .Math. s] 4.3 1.2 0.2 Shore D (1 d SCC) n.m..sup.2 n.m..sup.2 n.m..sup.2 (2 d SCC) 50 n.m..sup.3 n.m..sup.2 .sup.1 produced as described above .sup.2too soft .sup.3too brittle/fragile
Production of Polyurethane Adhesives with High Sag Resistance During Application:

Examples 11 to 13

[0256] For each example the ingredients of the polyol component specified in table 4 were mixed in the specified amounts (in parts by weight) using the centrifugal mixer and stored with exclusion of moisture.

[0257] The ingredients of the isocyanate component specified in table 4 were also processed and stored.

[0258] Subsequently the two components for each example were mixed using the centrifugal mixer and the sag resistance of each composition was immediately determined. To this end, 8 ml of the freshly mixed composition were applied from a commercial 10 ml plastic syringe that had been cut open at the front onto a piece of horizontal cardboard from above, and the cardboard with the applied composition was immediately tipped into the vertical position so that the applied composition projected horizontally. The extent of sagging from the horizontal position downwards during curing under standard climatic conditions was then assessed. A very small amount of sagging was described as very good and severe sagging was described as poor.

[0259] The results are reported in table 4.

[0260] Comparative examples are marked (Ref.).

TABLE-US-00005 TABLE 4 Composition and properties of examples 11 to 13. 12 13 Example 11 (Ref.) (Ref.) Polyol component: Voranol CP 4755 .sup.1 52.2 52.2 52.2 1,4-butanediol 7.4 7.4 8.4 Amine A1 2.0 MXDA 2.0 Calcined kaolin .sup.2 33.3 33.3 33.3 Molecular sieve 3 4.9 4.9 4.9 DABCO 33 LV .sup.3 0.2 0.2 0.2 Isocyanate component: Desmodur CD-L .sup.4 32.3 32.3 32.3 Polymer-1 .sup.5 46.2 46.2 46.2 Pyrogenic silica .sup.6 3.3 3.3 3.3 Sag resistance very good very good poor .sup.1 EO-capped polyoxypropylenetriol, OH number 34.7 mg KOH/g (Dow) .sup.2 Satintone W (BASF) .sup.3 33% by weight 1,4-diazabicyclo[2.2.2]octane in dipropylene glycol (Evonik) .sup.4 Carbodiimide-modified diphenylmethane diisocyanate, NCO content 29.5% by weight (Covestro) .sup.5 NCO content 2.07% by weight produced as described below .sup.6 Aerosil 200 (Evonik)

[0261] Polymer-1 was produced by reacting 1300 g of polyoxypropylenediol (Acclaim 4200 N, OH number 28.5 mg KOH/g, Covestro), 2600 g of EO-capped polyoxypropylenetriol (Voranol CP 4755, OH number 34.7 mg KOH/g, Dow), 600 g of 4,4-diphenylmethane diisocyanate (Desmodur 44 MC L, Covestro) and 500 g of diisodecyl phthalate by known methods at 80 C. to afford an isocyanate-containing polymer having an NCO content of 2.07% by weight.