ISOCYANATE-GROUP-CONTAINING POLYMER HAVING A LOW CONTENT OF MONOMERIC DIISOCYANATES

Abstract

A polyetherurethane polymer containing isocyanate groups and having an NCO content in the range from 1.3% to 1.9% by weight and a monomeric diisocyanate content of not more than 0.5% by weight, obtained from the reaction of at least one monomeric aromatic diisocyanate and a polyether triol having an average OH functionality in the range from 2.2 to 2.6 and an OH number in the range from 25 to 32 mg KOH/g in an NCO/OH ratio of at least 3/1 and subsequent removal of a majority of the monomeric diisocyanates by means of a suitable separation method, and to moisture-curing polyurethane compositions having a monomeric diisocyanate content of less than 0.1% by weight, comprising said polymer.

Claims

1. A polyetherurethane polymer containing isocyanate groups, wherein it has an NCO content in the range from 1.3% to 1.9% by weight, and a monomeric diisocyanate content of not more than 0.5% by weight, and in that it is obtained from the reaction of at least one monomeric aromatic diisocyanate and a polyether triol having an average OH functionality in the range from 2.2 to 2.6 and an OH number in the range from 25 to 32 mg KOH/g in an NCO/OH ratio of at least 3/1 and subsequent removal of a majority of the monomeric aromatic diisocyanate by means of a suitable separation method.

2. The polymer as claimed in claim 1 wherein it has an average molecular weight M.sub.n in the range from 5,000 to 15,000 g/mol, determined by means of gel permeation chromatography versus polystyrene standard with tetrahydrofuran as mobile phase, refractive index detector and evaluation from 200 g/mol.

3. The polymer as claimed in claim 1, wherein the monomeric aromatic diisocyanate is diphenylmethane 4,4′-diisocyanate.

4. The polymer as claimed in claim 1, wherein the polyether triol has an OH number in the range from 25 to 32 mg KOH/g and, based on all repeat units, has 80% to 90% by weight of 1,2-propyleneoxy groups and 10% to 20% by weight of 1,2-ethyleneoxy groups.

5. The polymer as claimed in claim 1, wherein the excess monomeric diisocyanate is removed by means of a distillative method.

6. The polymer as claimed in claim 1, wherein its NCO content is at least 80% of the theoretical NCO content which is calculated from the addition of one mole of monomeric diisocyanate per mole of OH groups of the polyether triol.

7. A moisture-curing polyurethane composition having a monomeric diisocyanate content of less than 0.1% by weight based on the overall composition, containing the polymer as claimed in claim 1.

8. The composition as claimed in claim 7, wherein it has a content of polymer in the range from 10% to 80% by weight.

9. The composition as claimed in claim 7, wherein it additionally comprises at least one blocked amine.

10. The composition as claimed in claim 7, wherein it additionally comprises at least one further constituent selected from oligomeric isocyanates, catalysts, fillers and plasticizers.

11. A method of adhesive bonding or sealing, comprising the steps of (i) applying the composition as claimed in claim 7 to a first substrate and contacting the composition with a second substrate within the open time of the composition, or to a first and to a second substrate and joining the two substrates within the open time of the composition, or between two substrates, (ii) curing the composition by contact with moisture.

12. A method of coating or sealing, comprising the steps of (i) applying the composition as claimed in claim 7 to a substrate, (ii) curing the composition by contact with moisture.

13. An article obtained from the method as claimed in claim 11.

Description

EXAMPLES

[0167] Working examples are adduced hereinafter, which are intended to elucidate the invention described. The invention is of course not limited to these described working examples.

[0168] “Standard climatic conditions” refer to a temperature of 23±1° C. and a relative air humidity of 50±5%.

[0169] Unless stated otherwise, the chemicals used were from Sigma-Aldrich.

Polyols Used:

[0170] Desmophen® 5031 BT: glycerol-started ethylene oxide-terminated polyoxypropylene triol, OH number 28 mg KOH/g, OH functionality about 2.3 (from Covestro); [0171] molecular weight M.sub.n determined by means of GPC about 6000 g/mol [0172] Acclaim® 6300: glycerol-started polyoxypropylene triol, OH number 28 mg KOH/g, OH functionality >2.9 (from Covestro); [0173] molecular weight M.sub.n determined by means of GPC about 6700 g/mol [0174] Voranol® CP 4755: glycerol-started ethylene oxide-terminated polyoxypropylene triol, OH number 35 mg KOH/g, OH functionality about 2.4 (from Dow); [0175] molecular weight M.sub.n determined by means of GPC about 4900 g/mol [0176] Acclaim® 4200: polyoxypropylene diol, OH number 28 mg KOH/g (from Covestro) [0177] Dynacoll® 7360 polyester diol which is solid and semicrystalline at room temperature, OH number 34 mg KOH/g (from Evonik)

Preparation of Polymers Containing Isocyanate Groups:

[0178] Viscosity was measured with a thermostated Rheotec RC30 cone-plate viscometer (cone diameter 25 mm, cone angle 1°, cone tip-plate distance 0.05 mm, shear rate 10 s.sup.−1).

[0179] Average molecular weight (number-average M.sub.n) was determined by means of gel permeation chromatography (GPC) against polystyrene (474 to 2 520 000 g/mol) as standard with tetrahydrofuran as mobile phase, refractive index detector and evaluation from 200 g/mol.

[0180] Monomeric diisocyanate content was determined by means of HPLC (detection via photodiode array; 0.04 M sodium acetate/acetonitrile as mobile phase) after prior derivatization by means of N-propyl-4-nitrobenzylamine.

Polymer P1: (Inventive)

[0181] 725.0 g of Desmophen® 5031 BT polyether triol and 275.0 g of diphenylmethane 4,4′-diisocyanate (Desmodur® 44 MC L, from Covestro) were reacted by a known method at 80° C. to give a polyetherurethane polymer having an NCO content of 7.6% by weight, a viscosity of 6.5 Pa.Math.s at 20° C. and a monomeric diphenylmethane 4,4′-diisocyanate content of about 20% by weight. Subsequently, the volatile constituents, especially a majority of the monomeric diphenylmethane 4,4′-diisocyanate, were removed by distillation in a short-path evaporator (jacket temperature 180° C., pressure 0.1 to 0.005 mbar, condensation temperature 47° C.). The polyetherurethane polymer thus obtained had an NCO content of 1.7% by weight, a viscosity of 19 Pa.Math.s at 20° C., a monomeric diphenylmethane 4,4′-diisocyanate content of 0.04% by weight and an average molecular weight M.sub.n of about 6900 g/mol.

Polymer P2: (Noninventive)

[0182] 724.0 g of Acclaim® 6300 polyether triol and 276.0 g of diphenylmethane 4,4′-diisocyanate (Desmodur® 44 MC L, from Covestro) were reacted by a known method at 80° C. to give a polyetherurethane polymer having an NCO content of 7.5% by weight, a viscosity of 9.9 Pa.Math.s at 20° C. and a monomeric diphenylmethane 4,4′-diisocyanate content of about 20% by weight. Subsequently, the volatile constituents, especially a majority of the monomeric diphenylmethane 4,4′-diisocyanate, were removed by distillation in a short-path evaporator (jacket temperature 180° C., pressure 0.1 to 0.005 mbar, condensation temperature 47° C.). The polyetherurethane polymer thus obtained had an NCO content of 1.7% by weight, a viscosity of 34.7 Pa.Math.s at 20° C., a monomeric diphenylmethane 4,4′-diisocyanate content of 0.06% by weight and an average molecular weight M.sub.n of about 9300 g/mol.

Polymer P3: (Noninventive)

[0183] 682.9 g of Voranol® CP 4755 polyether triol and 317.0 g of diphenylmethane 4,4′-diisocyanate (Desmodur® 44 MC L, from Covestro) were reacted by a known method at 80° C. to give a polyetherurethane polymer having an NCO content of 8.8% by weight, a viscosity of 5.1 Pa.Math.s at 20° C. and a monomeric diphenylmethane 4,4′-diisocyanate content of about 25% by weight. Subsequently, the volatile constituents, especially a majority of the monomeric diphenylmethane 4,4′-diisocyanate, were removed by distillation in a short-path evaporator (jacket temperature 180° C., pressure 0.1 to 0.005 mbar, condensation temperature 47° C.). The polyetherurethane polymer thus obtained had an NCO content of 2.0% by weight, a viscosity of 16.8 Pa.Math.s at 20° C., a monomeric diphenylmethane 4,4′-diisocyanate content of 0.05% by weight and an average molecular weight M.sub.n of about 5700 g/mol.

Polymer P4: (Noninventive)

[0184] 727.0 g of Acclaim® 4200 polyether diol and 273.0 g of diphenylmethane 4,4′-diisocyanate (Desmodur® 44 MC L, from Covestro) were reacted by a known method at 80° C. to give a polyetherurethane polymer having an NCO content of 7.6% by weight, a viscosity of 5.2 Pa.Math.s at 20° C. and a monomeric diphenylmethane 4,4′-diisocyanate content of about 18% by weight. Subsequently, the volatile constituents, especially a majority of the monomeric diphenylmethane 4,4′-diisocyanate, were removed by distillation in a short-path evaporator (jacket temperature 180° C., pressure 0.1 to 0.005 mbar, condensation temperature 47° C.). The polyetherurethane polymer thus obtained had an NCO content of 1.8% by weight, a viscosity of 15.2 Pa.Math.s at 20° C. and a monomeric diphenylmethane 4,4′-diisocyanate content of 0.08% by weight.

Polymer P5: (Noninventive)

[0185] 1000 g of Dynacoll® 7360 polyether diol and 142 g of diphenylmethane 4,4′-diisocyanate (Desmodur® 44 MC L, from Covestro) were reacted by a known method at 80° C. to give a room temperature solid polymer having an NCO content of 2.0% by weight and a monomeric diphenylmethane 4,4′-diisocyanate content of 2.3% by weight.

[0186] Polymer P5 is a conventionally prepared room temperature solid polymer that can be used to improve the initial bond strength of an adhesive.

Preparation of Blocked Amines:

[0187] Aldimine A1: N,N′-Bis(2,2-dimethyl-3-lauroyloxypropylidene)-3-aminomethyl-3,5,5-trimethylcyclohexylamine

[0188] 100.0 g (0.35 mol) of 2,2-dimethyl-3-lauroyloxypropanal were initially charged in a round-bottom flask under a nitrogen atmosphere. Then 27.9 g (0.16 mol) of 3-aminomethyl-3,5,5-trimethylcyclohexylamine (Vestamin® IPD, from Evonik) were added with good stirring and then the volatile constituents were removed at 80° C. and a reduced pressure of 10 mbar. What was obtained was a colorless liquid having an amine value of 153 mg KOH/g, corresponding to a calculated aldimine equivalent weight of 367 g/mol.

Moisture-Curing Polyurethane Compositions:

Compositions Z1 to Z4:

[0189] For each composition, the ingredients specified in table 1 were mixed in the amounts specified (in parts by weight) by means of a planetary mixer under reduced pressure and with exclusion of moisture, and stored with exclusion of moisture.

[0190] The thickener paste was produced by gently heating an initial charge of 300 g of diisodecyl phthalate and 48 g of diphenylmethane 4,4′-diisocyanate (Desmodur® 44 MC L, from Covestro) in a vacuum mixer and then slowly adding 27 g of monobutylamine dropwise while stirring vigorously. The resultant paste was stirred for a further hour under reduced pressure while cooling.

[0191] Each composition was tested as follows:

[0192] As a measure of storage stability, the expression force of the composition after storage was determined by storing one closed cartridge in each case at room temperature for 7 days or at 60° C. in an air circulation oven for 7 days, and then measuring the expression force by means of an expression device (Zwick/Roell Z005). For this purpose, the cartridge, after being conditioned under standard climatic conditions for 12 hours, was opened, a nozzle of internal diameter 3 mm was screwed on to the cartridge and then the force required to express the composition through the nozzle at an expression rate of 60 mm/min was measured. The value reported is the average of the forces that were measured after an expression distance of 22 mm, 24 mm, 26 mm and 28 mm. The results are given the addition “7d RT” or “7d 60° C.” according to the manner of storage of the closed cartridge.

[0193] A measure determined for the processing time (open time) was the skin time. For this purpose, a few grams of the composition were applied to cardboard in a layer thickness of about 2 mm and, under standard climatic conditions, the time until there were for the first time no longer any residues remaining on an LDPE pipette used to gently tap the surface of the composition was determined. Curing rate was determined by applying the composition as a free-standing cone of diameter 3 cm, leaving it to stand under standard climatic conditions or at 10° C./50% relative humidity, cutting it open with a crosscut after 24 h and measuring the layer thickness of the cured polymer ring formed. These results are reported in table 2 as “after 24 h” with the addition “(SCC)” or “(10° C./50%)” according to the climatic conditions on curing. Additional cones were cut open after a few days, and the thickening cured layer was determined until it was at least 10 mm. What is reported as “for 10 mm” in table 2 is the time until attainment of a cured layer of layer thickness at least 10 mm.

[0194] For determination of mechanical properties and heat stability, each composition was pressed between two wax-coated transfer printing papers to give a film of thickness 2 mm and stored under standard climatic conditions for 14 days. After removing the wax papers, some test specimens were punched out and tested as described as follows:

[0195] For determination of tensile strength (“TS”), elongation at break and modulus of elasticity at 0.5-50% elongation (“MoE 50%”), dumbbells having a length of 75 mm with a bar length of 30 mm and a bar width of 4 mm were punched out of the film, and these were tested to DIN EN 53504 at a strain rate of 200 mm/min. These results are given the addition “14 d SCC”. As a measure of heat stability, further punched-out dumbbells were stored at 90° C. in an air circulation oven for 7 days, cooled down under standard climatic conditions and tested in the same way. These results are given the addition “7 d 90° C.”.

[0196] Moreover, some test specimens, for determination of tear propagation resistance (“Tear prop.”), were punched out and tested to DIN ISO 34 at a strain rate of 500 mm/min.

[0197] To determine the strength of an adhesive bond, lap shear strength (LSS) was determined on glass. For this purpose, test specimens were produced by bonding two glass plates that had been degreased with isopropanol and pretreated with Sika® Aktivator 100 (from Sika Schweiz) in such a way that the overlapping adhesive bond had dimensions of 12×25 mm and a thickness of 4 mm and the glass plates protruded at the top ends. After the composite bodies had been stored under standard climatic conditions for 14 d, lap shear strength was tested to DIN EN 1465 at a strain rate of 20 mm/min. As a measure of the heat and hydrolysis stability of the bond, further test specimens were additionally stored in an air circulation oven at 90° C. or at 70° C./100% relative humidity for 7 days, cooled down under standard climatic conditions and tested in the same way. The results are given the addition “14d SCC” or “7d 90° C.” or “7d 70/100”. Shore A hardness was determined according to DIN 53505 on test specimens cured under standard conditions for 1 d, 2 d and 7 d. The evolution of Shore A hardness also served as a measure of curing rate. These results are given the addition “1d SCC” or “2d SCC or “7d SCC”. As a measure of heat and hydrolysis stability, Shore A test specimens that had been stored in this way were additionally stored in an air circulation oven at 90° C. or at 70° C./100% relative humidity for 7 and 30 days, and Shore A hardness was determined after cooling under standard climatic conditions. These results are given the addition “+7d 90° C.” or “+30d 90° C.” or “+7d 70/100” or “+30d 70/100”. 60% tensile stress and 100% tensile stress were determined with concrete test specimens (pretreated with Sika® Primer 3N, from Sika Schweiz), in each case at 23° C. and at −20° C. to DIN EN 28339, Method A. A low value at −20° C. and a small rise in the value between 23 and −20° C. show high cold flexibility. Additionally used as a measure of yellowing was the change in color of a film cured under standard climatic conditions after the time specified in table 2 and storage under standard climatic conditions “SCC” on a windowsill, or after stress in a QUV system “QUV”, or after stress in a weathering tester of the Q-Sun Xenon Xe-1 type with a Q-SUN Daylight-Q optical filter and a xenon lamp having a light intensity of 0.51 W/m.sup.2 at 340 nm at a temperature of 65° C. (“Q-Sun”). The color difference ΔE of the stressed film versus the corresponding unstressed film was then determined using an NH310 colorimeter from Shenzen 3NH Technology Co. LTD equipped with silicon photoelectric diode detector, light source A, color space measurement interface CIE L*a*b*C*H*. A high ΔE value means a great difference in color.

[0198] As a comparative example (Ref.), Sikaflex®-11 FC.sup.+ (from Sika) was tested in the same way. Sikaflex®-11FC.sup.+ is a commercially available elastic moisture-curing polyurethane sealant/adhesive having a monomeric diisocyanate content of less than 0.1% by weight, based on polyetherurethane polymers containing isocyanate groups, which have been produced conventionally without removal of the excess monomeric diisocyanates.

[0199] The results are reported in table 2.

[0200] The compositions labeled “(Ref.)” are comparative examples.

TABLE-US-00001 TABLE 1 Composition (in parts by weight) of Z1 to Z4. Z3 Z4 Composition Z1 Z2 (Ref.) (Ref.) Polymer P1 25.00 17.00 — — Polymer P2 — — 25.00 17.00 Polymer P4 — 8.00 — 8.00 Diisodecyl phthalate 4.00 4.00 4.00 4.00 Thickener paste 23.00 23.00 23.00 23.00 Aldimine A1 0.90 0.90 0.90 0.90 p-Toluenesulfonyl 0.10 0.10 0.10 0.10 isocyanate Epoxysilane.sup.1 0.50 0.50 0.50 0.50 Salicylic acid solution.sup.2 1.50 1.50 1.50 1.50 Dibutyltin dilaurate 0.01 0.01 0.01 0.01 Chalk.sup.3 40.00 40.00 40.00 40.00 Titanium dioxide 5.00 5.00 5.00 5.00 .sup.13-Glycidoxypropyltrimethoxysilane .sup.25% by weight of salicylic acid in dioctyl adipate .sup.3Omya BSH ® - OM (from Omya)

TABLE-US-00002 TABLE 2 Properties of Sikaflex ®-11FC.sup.+ (comparison) and Z1 to Z4. Sikaflex ®- 11FC.sup.+ Z3 Z4 Composition (Ref.) Z1 Z2 (Ref.) (Ref.) Expression force [N] 7 d 415 640 560 690 590 RT (3 mm nozzle) 7 d 60° C. 620 815 740 935 740 Skin time [min] 50 80 110 50 90 Curing rate: (SCC) after 24 h 3.5 mm 3.8 mm 3.4 mm 3.8 mm 3.6 mm for 10 mm 10 d 7 d 8 d 8 d 8 d (10° C./50%) after 24 h 2.1 mm 2.6 mm 2.1 mm 2.5 mm 2.2 mm for 10 mm 21 d 15 d 15 d 16 d 16 d 14 d SCC: TS [MPa] 1.73 1.62 1.83 1.14 1.15 Elongation at break [%] 830 620 815 260 360 MoE 50% [MPa] 1.03 1.13 1.06 1.71 1.59 7 d 90° C.: TS [MPa] 1.18 1.73 1.26 1.24 1.30 Elongation at break [%] 875 725 875 295 465 MoE 50% [MPa] 0.76 1.10 0.91 1.90 1.59 Tear prop. [N/mm] 7.1 7.1 8.0 4.4 5.3 LSS [MPa] 14 d SCC 0.93 0.84 0.94 0.75 0.77 7 d 90° C. 0.83 0.98 0.83 0.82 0.86 7 d 70/100 0.59 0.84 0.85 0.74 0.75 Shore A 1 d SCC 10 30 20 41 38 2 d SCC 19 37 31 49 46 7 d SCC 32 38 33 50 46 +7 d 90° C. 29 37 29 51 43 +30 d 90° C. 24 37 28 51 41 +7 d 70/100 24 37 31 50 44 +30 d 70/100 18 32 26 45 40 60% tensile stress at 23° C. 0.45 0.65 0.58 tears 0.88 [MPa] at −20° C. 0.98 0.90 0.87 1.37 1.22 100% tensile stress at 23° C. 0.52 0.72 0.64 tears tears [MPa] at −20° C. 1.13 1.12 1.00 1.39 1.26 Yellowing ΔE 1000 h SCC 3.6 0.9 not not not after 1000 h Q-Sun 6.1 3.2 determined determined determined 1000 h QUV 12.2 8.7

[0201] Table 2 shows the properties of one-component polyurethane compositions having no labeling. The comparison of the inventive composition Z1 with the commercial product Sikaflex®-11FC.sup.+ shows a massive improvement in stability with respect to heat and yellowing coupled with faster curing. The comparison of compositions Z1 and Z2 based on the inventive polymer P1 with reference compositions Z3 and Z4 based on the noninventive polymer P2 proceeding from a triol having higher functionality in each case shows a longer open time (skin time) coupled with somewhat faster curing, massively higher elongation at break coupled with distinctly higher strength and higher tear propagation resistance, each of which are at the level of the commercial product Sikaflex®-11FC.sup.+.

Compositions Z5 and Z6:

[0202] For each composition, the ingredients specified in table 3 were mixed in the amounts specified (in parts by weight) by means of a planetary mixer under reduced pressure and with exclusion of moisture, and stored with exclusion of moisture. Each composition was tested as follows:

[0203] Expression force was tested as for composition Z1, except using a nozzle of internal diameter 5 mm, and with determination of an additional value after storage at 60° C. for 14 days.

[0204] Skin time and tear propagation resistance were tested as for composition Z1. Tensile strength and elongation at break were tested as for composition Z1, except that modulus of elasticity (0.5-5%) was read off in the range from 0.5% to 5% elongation. As a measure of heat and hydrolysis stability, further dumbbells were stored in an air circulation oven at 100° C. or at 70° C./100% relative humidity for 7 days, cooled down under standard climatic conditions and tested in the same way. These results are given the addition “7d 100° C.” or “7d 70/100”.

[0205] Lap shear strength (LSS) was tested as for composition Z1.

[0206] As a measure of opening time at 35° C./80% relative humidity, bonding after wait time was tested by degreasing multiple glass plates of size 40×100 mm with isopropanol, pretreating with Sika® Aktivator 100 (from Sika Schweiz) and then applying the composition at 35° C./80% relative humidity in longitudinal direction in the form of a triangular bead (10×10×10 mm). Subsequently, these test specimens were stored at 35° C./80% relative humidity for the wait time specified in table 3 (3 min up to 12 min), then covered with a piece of Teflon paper, and the triangular bead was compressed to a thickness of 4.5 mm and stored in this way for 7 d, in the course of which the composition applied cured. Subsequently, the Teflon paper was removed and the bonding of the compressed bead on the glass plate was tested by making an incision into the cured composition at the narrow end just above the bonding surface, holding the cut end of the composition with rounded tweezers and trying to pull the composition away from the substrate. Then the composition was incised again down to the substrate, the part that had been cut away was rolled up with the rounded tweezers and an attempt was again made to pull the composition away from the substrate. In this way, the composition was cut away from the substrate by puffing over a length of 80 mm. Subsequently, bonding was assessed with reference to the failure profile using the following scale:

“very good” represents more than 95% cohesive failure,
“good” represents 75% to 95% cohesive failure,
“moderate” represents 25% to 75% cohesive failure,
“poor” represents less than 25% cohesive failure, and
“no adhesion” represents 0% cohesive failure or 100% adhesive failure

[0207] The end of the open time has been reached as soon as adhesion is no longer “very good”.

[0208] The results are reported in table 3.

[0209] The compositions labeled “(Ref.)” are comparative examples.

TABLE-US-00003 TABLE 3 Composition (in parts by weight) and properties of Z5 and Z6. Z6 Composition Z5 (Ref.) Polymer P1 34.3 — Polymer P3 — 34.3 Polymer P5 4.0 4.0 Dioctyl adipate 22.5 22.5 Chalk 21.0 21.0 Carbon black 18.0 18.0 2,2′-Dimorpholinodiethyl ether 0.2 0.2 Expression force [N] 7 d RT 1377 1238 (5 mm nozzle) 7 d 60° C. 1407 1424 14 d 60° C. 1446 1534 Skin time [min] 18 18 7 d SCC: Tensile strength [MPa] 7.1 6.2 Elongation at break [%] 480 300 Elastic modulus (0.5-5%) [MPa] 4.8 6.1 7 d 100° C.: Tensile strength [MPa] 8.7 7.1 Elongation at break [%] 480 280 Elastic modulus (0.5-5%) [MPa] 4.0 5.0 7 d 70/100: Tensile strength [MPa] 8.5 7.5 Elongation at break [%] 470 300 Elastic modulus (0.5-5%) [MPa] 3.6 4.7 Tear propagation resistance [N/mm] 10.9 8.9 Lap shear strength 14 d SCC 3.3 4.0 [MPa] 7 d 70/100 3.7 4.5 Adhesion after wait time  3 min very good very good (35° C./80% RH)  4 min very good very good  5 min very good very good  6 min very good very good  7 min very good good  8 min very good good  9 min very good moderate 10 min very good poor 11 min good poor 12 min moderate no adhesion

[0210] It is apparent from table 3 that composition Z5 based on the inventive polymer P1, compared to composition Z6 based on the noninventive polymer P3 with a somewhat shorter chain length (higher NCO value and high OH number of the parent triol), has higher elongation coupled with higher tensile strength, higher tear propagation resistance and longer open time in the bonding of glass under moist and warm conditions.