POLYCARBONATE POLYOLS, POLYISOCYANATE PREPOLYMERS AND POLYURETHANE AND POLYURETHANE UREA ELASTOMERS BASED THEREON

Abstract

The present invention relates to novel high-value polycarbonate polyols, to processes for the production thereof, to polyisocyanate prepolymers obtainable therefrom and also polyurethane (PUR) and polyurethane urea elastomers which under particularly demanding applications show unique combinations of processing characteristics, hydrolysis and oxidation stability, mechanical and dynamic mechanical properties.

Claims

1.-15. (canceled)

16. A polycarbonate polyol having an OH number of 40 to 80 mg KOH/g according to DIN 53240-1 of June 2013 (without catalyst) and a mean functionality of 1.9 to 2.2, comprising the reaction product of A) at least one α,ω-alkanediol having 4 to 8 carbon atoms and B) at least one polytetrahydrofuran, and optionally C) diethylene glycol with at least one D) carbonyl component selected from the group consisting of diaryl carbonates, dialkyl carbonates, cyclic alkylene carbonates and COC1.sub.2, and mixtures thereof.

17. The polycarbonate polyol as claimed in claim 16, wherein the at least one α, ω-alkanediol having 4 to 8 carbon atoms (A) is selected from the group consisting of 1,4-butanediol, 2-methylpropane- 1,3-diol, 1,5-pentanediol, 3-methylpentane- 1,5-diol, 1,6-hexanediol and 1,8-octanediol, preferably 1,6-hexanediol, and mixtures thereof.

18. The polycarbonate polyol as claimed in claim 16, wherein the at least one polytetrahydrofuran (B) has number-average molecular weights in the range from 250 to 2900 Da.

19. The polycarbonate polyol as claimed in claim 16, wherein the molar ratio of carbonate groups to ether groups is in the range from 0.2:1 to 3.5:1.

20. The polycarbonate polyol as claimed in claim 16, wherein for a sample stored for more than four weeks at room temperature, a maximum in a melting endotherm determined by DSC according to DIN EN ISO 11357-1 from March 2010 at a heating rate of 10° C./min is in the range from 9 to 59° C.

21. A process for preparing a polycarbonate polyol as claimed in claim 16, wherein a two-stage process is employed, wherein in a first stage, in the presence of a catalyst, an intermediate is prepared from A) at least one α, ω-alkanediol having 4 to 8 carbon atoms, C) optionally diethylene glycol, and D) at least one carbonyl component from the group consisting of diaryl carbonates, dialkyl carbonates, alkylene carbonates and COCl.sub.2, and mixtures thereof, and in a second stage this intermediate is reacted with B) at least one polytetrahydrofuran.

22. The process as claimed in claim 21, wherein in the second stage, in addition to the B) at least one polytetrahydrofuran, for compensating the diols A) and/or C) partially removed in the first stage, A) at least one α, ω-alkanediol having 4 to 8 carbon atoms and/or C) diethylene glycol are/is added.

23. The process as claimed in claim 21, wherein in the first stage, the components A) and/or C) are used in excess in an amount which produces a deviation of 2 to 20 hydroxyl number units relative to the actual target hydroxyl number.

24. An NCO prepolymer based on the polycarbonate polyol as claimed in claim 16.

25. The NCO prepolymer as claimed in claim 24, having an NCO content of 3 to 15 wt %, obtained by reacting a polycarbonate polyol as claimed in claim 16 with at least one polyisocyanate from the group consisting of 1,5-naphthalene diisocyanate, 2,4′-diphenylmethane diisocyanate (2,4′-MDI), 4,4′-diphenylmethane diisocyanate (4,4′-MDI), mixtures of 2,4′- and 4,4′-MDI, carbodiimide/uretonimine-modified MDI derivatives and higher polycyclic homologs of the diphenylmethane series, diisocyanatotoluenes, hexamethylene diisocyanate, isophorone diisocyanate, and mixtures thereof in a molar excess.

26. A polyurethane elastomer or polyurethaneurea elastomer based on an NCO prepolymer as claimed in claim 24.

27. A polyurethane elastomer or polyurethaneurea elastomer obtained by reacting an NCO prepolymer as claimed in claim 24 with (i) at least one aliphatic diol having primary hydroxyl groups and a number-average molecular weight of 62 to 202 and in amounts of 0-10 wt %, based on the at least one aliphatic diol, compounds from the group consisting of short-chain polyols having functionalities >2 to 4 and polyols of higher molecular weight, having a functionality of 2, and polycarbonate polyols as claimed in claim 16, optionally in the presence of water, and optionally further auxiliaries and adjuvants, and/or (ii) at least one aromatic diaminic chain extender selected from the group consisting of 4,4′-methylenebis(2-chloroaniline) (MBOCA), 3,3′,5,5′-tetraisopropyl-4,4′-diaminodiphenylmethane, 3,5-dimethyl-3′,5′-diisopropyl-4,4′-diaminophenylmethane, 3,5-diethyl-2,4-tolylenediamine, 3,5-diethyl-2,6-tolylenediamine (DETDA), 4,4′-methylenebis(3-chloro-2,6-diethylaniline), 3,5-dimethylthio-2,4-tolylenediamine, 3,5-dimethylthio-2,6-tolylenediamine, isobutyl 3,5-diamino-4-chlorobenzoate, and mixtures thereof, optionally in the presence of water, and optionally further auxiliaries and adjuvants.

28. A method comprising providing the polyurethane elastomer or polyurethaneurea elastomer as claimed in claim 26 for producing technical components.

29. A method of utilizing the polyurethane elastomer or polyurethaneurea elastomer as claimed in claim 26 as roll coating material or shoe press blankets, as pigs, pig disks, seals, pipe coatings, stiffening elements for pipes or cables, conveyor belts or screens, doctor blades, wheels, rollers, or potting compound.

30. A technical component, roll coating, shoe press blanket, electrical casting, pig, pig disk, seal, pipe coating, stiffening element for pipes or cables, doctor blade, wheel, roller, conveyor belt or screen comprising a polyurethane elastomer or polyurethaneurea elastomer as claimed in claim 26.

Description

[0096] In the case of NDI-based formulations, the test specimens immediately after demolding are thermally aftertreated for 24 h at 110° C. in a forced air drying cabinet. Prior to the determination of the mechanical properties, the test specimens are stored for four weeks at room temperature and around 50% relative humidity.

WORKING EXAMPLES

1.) Synthesis of the Polycarbonate Polyols, Two-Stage Process (Inventive)

[0097] The inventive examples A-1 to A-5 were prepared according to the following process:

Example A-1: Polycarbonate Polyol From Polytetrahydrofuran, Diethylene Glycol and Hexanediol

[0098] A distillation apparatus consisting of a 10 liter four-neck flask, heating jacket, thermal sensor, ground-glass-joint adapter for introduction of nitrogen, stirrer, column, heated (45° C.) distillation bridge, heated (45° C.) descending Claisen condenser with heated (45° C.) tap, two-neck flask as receiver, thermometer for overhead temperature, membrane pump and oil pump was charged with 4386.9 g (20.38 mol) of diphenyl carbonate, 2054 g (17.35 mol) of hexanediol, 474 g (4.47 mol) of diethylene glycol and 122 mg of magnesium hydroxide carbonate pentahydrate, and this initial charge was heated slowly to 180° C. with stirring and with N2 blanketing. Stirring was carried out at 180° C. for 2 hours under standard pressure, after which the batch was cooled to 110° C. and reduced pressure was applied. When the pressure reached 15 mbar, phenol was distilled off, the overhead temperature being not more than 80° C.

[0099] When the distillation of phenol slowed down, the liquid-phase temperature was raised to eventually 200° C. in small steps. Under these reaction conditions, the reaction was completed over the course of one hour.

[0100] The pressure was subsequently reduced to around 0.5 to 1 mbar in order to remove remnants of phenol. The final mass of phenol was 3848 g (theoretical 3850 g). After cooling had taken place to around 80° C., a sample was taken for the purpose of determining the OH number and the end groups:

[0101] OH number: 46.3 mg KOH/g

[0102] End groups: phenyl carbonate end groups 0.07 wt %, phenol and phenoxy end groups: not detectable

[0103] The mass of the resultant intermediate was found to be 3007 g, and 506 g of polytetrahydrofuran 1000 (OH number 113.7 mg KOH/g) were added. Heating took place under N.sub.2 blanketing and with stirring at 200° C. for six hours. After cooling had taken place to around 80° C., a sample was taken for the purpose of determining the OH number and the viscosity. This was followed by neutralization, at 80° C., by the stirred incorporation of 720 mg of dibutyl phosphate.

[0104] OH number: 57.8 mg KOH/g

[0105] Viscosity: 2200 mPas (75° C.)

2.) Synthesis of the Polycarbonate Polyols, One-Stage Process (Not Inventive)

[0106] The noninventive examples A-6 and A-7 were prepared by the following method:

Example A-6: Polycarbonate Polyol From Polytetrahydrofuran 1000, Diethylene Glycol and Hexanediol

[0107] A distillation apparatus consisting of a 10 liter four-neck flask, heating jacket, thermal sensor, ground-glass-joint adapter for introduction of nitrogen, stirrer, column, heated (45° C.) distillation bridge, heated (45° C.) descending Claisen condenser with heated (45° C.) tap, two-neck flask as receiver, thermometer for overhead temperature, membrane pump and oil pump was charged with 4214 g (19.67 mol) of diphenyl carbonate, 2436.6 g (20.76 mol) of hexanediol, 1044.3 g (1.05 mol) of polytetrahydrofuran 1000 and 160 mg of magnesium hydroxide carbonate pentahydrate, and this initial charge was heated slowly to 180° C. with stirring and with N.sub.2 blanketing. The batch was stirred at 180° C. for two hours under standard pressure, after which it was cooled to 110° C. and reduced pressure was applied. Since, on reaching 15 mbar, no phenol was distilled off (in contrast to the inventive examples), the temperature was raised in steps, with a slight onset of phenol distillation at a liquid-phase temperature of 145° C., but with a rapid climb in the overhead temperature to 110° C. and the distillative removal not of phenol but of hexanediol (in contrast to the inventive examples).

[0108] Repeated lowering of the liquid-phase temperature to 140° C. did bring an end to the unwanted distillation of the hexanediol, but did not result in the reformation of further phenol—that is, when the liquid-phase temperature was raised, the overhead temperature climbed repeatedly to 110° C. The batch was discarded.

[0109] 3.) Synthesis of the Polycarbonate Polyols, One-Stage Process (Not Inventive)

[0110] The noninventive examples. A-8 and A-9 were prepared by the following process:

Example A-8: Polycarbonate Polyol From Diethylene Glycol and Hexanediol

[0111] A distillation apparatus consisting of a 6 liter four-neck flask, heating jacket, thermal sensor, ground-glass-joint adapter for introduction of nitrogen, stirrer, column, heated (45° C.) distillation bridge, heated (45° C.) descending Claisen condenser with heated (45° C.) tap, two-neck flask as receiver, thermometer for overhead temperature, membrane pump and oil pump was charged with 2865.1 g (13.38 mol) of diphenyl carbonate, 1181 g (10.06 mol) of hexanediol, 468.6 g (4.42 mol) of diethylene glycol and 80 mg of magnesium hydroxide carbonate pentahydrate, and this initial charge was heated slowly to 180° C. with stirring and with N.sub.2 blanketing. The batch was stirred at 180° C. for two hours under standard pressure, and then cooled to 110° C., and reduced pressure was applied.

[0112] When 15 mbar had been reached, phenol was distilled off, with the overhead temperature being not more than 80° C.

[0113] When the distillation of phenol slowed down, the liquid-phase temperature was raised to an eventual 200° C. in small steps. Under these reaction conditions, the reaction was completed over one hour.

[0114] The pressure was subsequently reduced to around 0.1 to 0.5 mbar in order to remove remnants of phenol. The final mass of phenol was 2517 g (theoretical 2515 g). After cooling had taken place to around 80° C., a sample was taken for the purpose of determining the OH number and the end groups. This was followed by neutralization, by stirred incorporation of 470 mg of dibutyl phosphate at 80° C.

[0115] OH number: 48.4 mg KOH/g

[0116] End groups: phenyl carbonate end groups 0.02 wt %, phenol 0.01 wt % and phenoxy end groups 0.04 wt %.

[0117] Viscosity: 4480 mPas (75° C.)

TABLE-US-00002 TABLE 1 Formulations and analytical data of inventive and noninventive polycarbonate polyols Example A-1, inv. A-2, inv. A-3, inv. A-4, inv. A-5, inv. A-6, comp. A-7, comp. A-8, comp. A-9, comp. Formulation: Diphenyl carbonate [g] 4386.9 4362.7 4150.2 3031.0 4307.0 4214.2 4319.0 2865.1 2533.7 Hexane-1,6-diol [g] 2054.0 2562.7 2479.6 1814.0 1910.3 2436.6 2427.6 1181.0 1255.7 Polytetrahydrofuran 650 [g] — — — — — — 1040.4 — — Polytetrahydrofuran 1000 [g] 506 540 — — 930.0 1044.3 — — — Polytetrahydrofuran 2000 [g] — — 900 1814.0 — — — — — Diethylene glycol [g] 474 — — — 536.5 — — 468.6 — Tetraethylene glycol [g] — — — — — — — — 434.4 Distilled phenol, exp [g] 3848 3826 3637 2660 3777 — — 2517 2226 Distilled phenol, theoret [g] 3850 3829 3642 2660 3780 3699 3791 2515 2224 Magnesium hydroxide [mg] 148 138 160 160 160 160 320 80 80 carbonate Dibutyl phosphate [mg] 866 807 937 933 933 — — 468 468 Calculated properties: Carbonate groups per kg of [mol/kg] 5.57 5.53 4.87 3.56 5.03 — — 6.69 5.92 product Ether groups per kg of [mol/kg] 3.39 2.15 3.58 6.27 4.56 — — 2.21 3.36 product Molar ratio of [mol/kg/mol/kg]] 1.64 2.57 1.36 0.57 1.10 — — 3.03 1.76 carbonate/ether groups Properties: OH number of precursor [mgKOH/g] 46.3 34.8 44.7 55.2 37.6 — — — — (exp.) OH number of end product [mgKOH/g] 57.8 54.8 55.8 50.0 52.0 — — 48.4 52.9 (exp.) Viscosity at 75° C. [mPa*s] 2200 2130 1680 2600 2540 — — 4480 2210 DSC max. [° C.] 33 47 47 43 15 — — amorphous 33 Phenoxy end groups [% by wt.] 0 0 0 0 0 — — 0.044 0.033 Phenol [% by wt.] 0 0 0 0.02 0 — — 0.011 0.085 Phenyl carbonate end groups [% by wt.] 0.07 0.21 0.22 0 0.09 — — 0.017 0 Mode 2-stage 2-stage 2-stage 2-stage 2-stage 1-stage 1-stage 1-stage 1-stage termination termination

4.) Synthesis of NCO Prepolymers

[0118] The NCO prepolymers were synthesized by reacting the polycarbonate polyols of examples A-1 to A-5 and A-8 to A-10 from table 1 with Desmodur 0118T:

Example B-1 (Inventive)

[0119] A 6 1 three-neck flask equipped with a heating jacket, stirring mechanism and an internal thermometer was charged with 1850 g (7.4 mol) of Desmodur 0118T under nitrogen blanketing of 50° C. with stirring. Then 3001 g of a polycarbonate polyol from example A-1, preheated to 80° C., were added with stirring over the course of around 10 minutes. Stirring then continued under nitrogen at 80° C. The reaction was at an end after 2 hours. The NCO content was 10.04 wt % and the viscosity was 1760 mPas (at 75° C.).

TABLE-US-00003 TABLE 2 Formulations and analytical data of the MDI-based NCO prepolymers; the initial masses are evident from the hydroxyl numbers of the polyols and from the NCO content of the Desmodur 0118T. Example: Polyol from Prepolymer B-1 B-2 B-3 B-4 B-5 B-8 B-9 example Initial mass inv. inv. inv. inv. inv. (C) (C) A-1, inv. [g] X — — — — — — A-2, inv. [g] — X — — — — — A-3, inv. [g] — — X — — — — A-4, inv. [g] — — — X — — — A-5, inv. [g] — — — — X — — A-8, comp. [g] — — — — — X — A-9, comp. [g] — — — — — — X Baytec C2208 [g] — — — — — — — Desmodur 118T [g] X X X X X X X NCO content [% by wt. 10.04 9.9 10 10.1 9.9 10.0 9.98 of NCO] Viscosity, 75° C. [mPas] 1760 2010 1890 2230 2020 4480 2210

[0120] 5.) Production of Casting Elastomers Based on 4,4 ′-Diphenylmethane Diisocyanate (MDI)

Example C-1, Inventive

[0121] 100 parts of a prepolymer (from example B-1), preheated to 70° C. and degassed, were stirred together with 10.15 parts of 1,4-butanediol for 30 seconds. The reacting melt was cast into metal molds, which were at a temperature of 115° C., and a temperature of 110° C. was maintained for 24 hours. After 21 days of storage at room temperature, the mechanical data were determined (table 3). All quantity figures are weight figures.

[0122] The inventive examples C-2 to C-5 and the comparative examples C-8 to C-9(C) were produced as described in example C-1 above.

TABLE-US-00004 TABLE 3 Production and properties of polyurethane and polyurethaneurea elastomers C-1 to C-9 (C) by reaction of the MDI prepolymers (B-1 to B-10 (Q) with butanediol; the parts by weight of MDI prepolymer and butanediol are evident from the NCO content of the prepolymer and from the specified index. C-1 C-2 C-3 C-4 C-5 C-8 C-9 inv. inv. inv. inv. inv. (C) (C) B-1 B-2 B-3 B-4 B-5 B-8 B-9 Prepolymer inv. inv. inv. inv. inv. (C) (C) Formulation: MDI prepolymer [parts] X X X X X X X NCO content of prep. [%] 10.04 9.9 10 10.1 9.9 10.0 9.98 Viscosity (70° C.) [mPas] 2750 3085 2965 2970 2965 4330 2810 Butanediol [parts] X X X X X X X Index 103 103 103 103 103 103 103 Processing: Prepolymer temperature [° C.] 70 70 70 70 70 70 70 Casting time [s] 250 260 250 220 250 180 180 Demolding time [min] — — — — — 60 60 Mechanical Shore A 97A 95.5A 96A 97A 95.5 98A 98A properties: Shore D 53D 47D 48D 53D 47D 55D 58D 100% modulus [MPa] 15.7 15.7 14.5 13.3 13.2 18.3 16.2 300% modulus [MPa] 32.4 41.6 33.9 26 32 30.3 34 Stress at yield [MPa] 52 57 47 54 52 49 44 Elongation at break [%] 410 382 391 474 417 414 400 Tear strength, without [kN/m] 159 151 149 152 152 176 163 notching Tear strength, with [kN/m] 112 82 82 101 69 124 104 notching Rebound resilience [%] 42 42 42 48 43 41 45 Abrasion [mm.sup.3] 65 65 55 50 45 66 89 Density [g/mm.sup.3] 1.19 1.18 1.17 1.16 1.19 1.16 1.16 CS 22 h 70° C. [%] 52 43 46 47 46 36 34 Glass transition [° C.] −9.0 −13.9 −13.4 not −12.1 5.8 −2.7 temperature, DMA determined

[0123] Table 3 shows that the inventive casting elastomers C-1 to C-5 readily achieve the given level of values in relation to the stress-strain characteristics, illustrated by the noninventive examples C-8(C) to C-10(C). The same is also true of the tear strengths, the abrasion behavior, and also, with some small deductions, of the compression set as well (CS). The inventive casting elastomers here, however, exhibit lower glass transition temperatures and accordingly display advantageous low-temperature characteristics.