Polyurethane foams comprising phosphorus compounds

Abstract

The present invention relates to polyurethanes obtained by mixing to give a reaction mixture of (a) polyisocyanate, (b) polymeric compounds having groups reactive toward isocyanates, (c) catalysts comprising incorporable amine catalysts, (d) phosphoric esters, polyphosphates, phosphonic esters, and/or phosphorous esters, and optionally (e) blowing agents, (f) chain extenders and/or crosslinking agents, and (h) auxiliaries and/or additives, and completing the reaction of the reaction mixture to give the polyurethane. The invention further relates to a process for producing these polyurethanes and to their use in automobile interiors.

Claims

1. A polyurethane foam obtained by a process comprising: mixing a reaction mixture comprising (a) polyisocyanate, (b) a polymeric compound comprising a group reactive toward isocyanates, (c) a catalyst composition consisting of at least one reactive amine catalyst and optionally one or more organometallic compounds, (d) at least one of a phosphoric ester, a polyphosphate, a phosphonic ester, and a phosphorous ester, (e) a blowing agent comprising water, (f) optionally a chain extender, a crosslinking agent, or both, and (g) optionally an additive, and reacting the reaction mixture to give the polyurethane foam, wherein the phosphoric ester has formula
(R.sup.1O).sub.3PO, wherein moieties R.sup.1 are independently organic moieties comprising one or more phenyl groups, one or more phosphoric acid groups or esters comprising the phenyl groups, the phosphoric acid groups, and optionally one or more atoms selected from the group consisting of nitrogen, oxygen, fluorine, chlorine, and bromine, the polyphosphate has formula
[P(O)(OR.sup.+)O].sub.n, wherein n is an integer of from 2 to 10 000 and R.sup.+ is an alkali metal cation or an ammonium cation, the phosphonic ester has formula
(R.sup.3)(R.sup.2O).sub.2PO, wherein moieties R.sup.2 are independently organic moieties comprising one or more atoms selected from the group consisting of nitrogen, oxygen, fluorine, chlorine, and bromine, and moiety R.sup.3 is either hydrogen or aromatic, aliphatic, or cycloaliphatic moieties comprising from 1 to 10 carbon atoms, the phosphorous ester has formula
(R.sup.4O).sub.3P, wherein moieties R.sup.4 are independently organic moieties comprising one or more atoms selected from the group consisting of nitrogen, oxygen, fluorine, chlorine, and bromine, wherein at least one of the phosphoric ester, the phosphonic ester, or the phosphorus ester is present and comprises a group which is reactive towards an isocyanate group wherein a proportion of component (d), based on a total volume of components (a) to (f), is smaller than 3% by weight; and wherein said reactive amine catalyst comprises groups reactive toward isocyanates, and optionally at least one tertiary aliphatic amino group comprising two moieties independently selected from the group consisting of a methyl moiety and an ethyl moiety, and an organic moiety; and wherein said polyurethane foam comprises less than 2% of further flame retardants.

2. The polyurethane foam according to claim 1, wherein the group of the phosphoric ester, the phosphonic ester, or the phosphorous ester which is reactive toward an isocyanate group comprises a group which is an OH group.

3. The polyurethane foam according to claim 1, wherein component (d) comprises compounds comprising at least two phosphate groups.

4. The polyurethane foam according to claim 1, wherein the polyurethane foam has an average density of from 100 to 850 g/L.

5. The polyurethane foam according to claim 4, wherein the polyurethane foam is a molded polyurethane foam.

6. The polyurethane foam according to claim 5, wherein the molded polyurethane foam has an average density of from 150 to 500 g/L.

7. The polyurethane foam according to claim 1, wherein the polyurethane foam is an automobile interior part.

8. The polyurethane foam according to claim 7, wherein the automobile interior part is a steering wheel, a dashboard, an interior door cladding, a headrest, or a control button.

9. The polyurethane foam according to claim 1, comprising no further flame retardants.

10. A process for producing a polyurethane foam, the process comprising: mixing a) polyisocyanate, b) polymeric compounds comprising groups reactive toward isocyanates, c) a catalyst composition consisting of at least one reactive amine catalyst and optionally one or more organometallic compounds, d) at least one of a phosphoric ester, a polyphosphate, a phosphonic ester, and a phosphorous ester, e) blowing agents comprising water, f) optionally chain extenders, crosslinking agents, or both, and g) optionally additives, thereby obtaining a reaction mixture, and reacting the reaction mixture, thereby obtaining the polyurethane foam, wherein the phosphoric ester has formula
(R.sup.1O).sub.3PO, wherein moieties R.sup.1 are independently organic moieties comprising one or more phenyl groups, one or more phosphoric acid groups or esters comprising the phenyl groups, the phosphoric acid groups, and optionally one or more atoms selected from the group consisting of nitrogen, oxygen, fluorine, chlorine, and bromine, the polyphosphate has formula
[P(O)(OR.sup.+)O].sub.n, wherein n is an integer of from 2 to 10 000 and R.sup.+ is an alkali metal cation or an ammonium cation, the phosphonic ester has formula
(R.sup.3)(R.sup.2O).sub.2PO, wherein moieties R.sup.2 are independently organic moieties comprising one or more atoms selected from the group consisting of nitrogen, oxygen, fluorine, chlorine, and bromine, and moiety R.sup.3 is either hydrogen or aromatic, aliphatic, or cycloaliphatic moieties comprising from 1 to 10 carbon atoms, the phosphorous ester has formula
(R.sup.4O).sub.3P, wherein moieties R.sup.4 are independently organic moieties comprising one or more atoms selected from the group consisting of nitrogen, oxygen, fluorine, chlorine, and bromine, wherein at least one of the phosphoric ester, the phosphonic ester, or the phosphorus ester is present and comprises a group which is reactive towards an isocyanate group wherein a proportion of component (d), based on a total volume of components (a) to (f), is smaller than 3% by weight; and wherein said reactive amine catalyst comprises groups reactive toward isocyanates, and optionally at least one tertiary aliphatic amino group comprising two moieties independently selected from the group consisting of a methyl moiety and an ethyl moiety, and an organic moiety; and wherein said polyurethane foam comprises less than 2% of further flame retardants.

11. A method for making an automobile interior, comprising: employing the polyurethane foam according to claim 1 in an automobile interior in need thereof.

12. The polyurethane foam according to claim 1, wherein said polyurethane foam comprises less than 1% of further flame retardants.

Description

(1) Examples are used below to illustrate the invention.

(2) Starting Materials:

(3) Polyol A: Polyetherol with OH number 35 mg KOH/g and functionality 2.7, based on ethylene oxide and propylene oxide, having 84% propylene oxide content and 14% ethylene oxide content Polyol B: Graft polyol having 45% solids content (styrene-acrylonitrile) in polyol A as carrier polyol MEG: Monoethylene glycol Isopur SA-21050: Black paste from ISL-Chemie Polycat 15: Catalyst from Air Products Jeffcat ZF-10: Catalyst from Huntsman
Phosphorus Compounds P1: Tris(1,3-dichloro-2-isopropyl) phosphate P2: Oligomeric alkyl phosphate having ethylene oxide bridges P3: Di(diethylene glycol) methylphosphonate P4: Exolit AP422ammonium polyphosphate from Clariant P5: Isopropylated triaryl phosphate P6: Tris(dipropylene glycol) phosphite P7: Tris(2-butoxyethyl) phosphate P8: Tris(2-chloroisopropyl) phosphate, TCPP P9: Tributyl phosphate (comparison) P10: Tributyl phosphite (comparison) P11: Trisnonylphenyl phosphite, TNPP (comparison) P12: Disflamoll TOFtris(2-ethylhexyl) phosphate (comparison), aliphatic phosphate from Lanxess
Isocyanate

(4) Carbodiimide-modified 4,4-MDI with an NCO content of 27.8

(5) The mixture A was prepared by blending the following components:

(6) TABLE-US-00001 79.9 parts of polyol A 4.8 parts of polyol B 8.1 parts of MEG 5.0 parts of Isopur SA-21050 0.6 parts of water 0.8 parts of Polycat 15 0.8 parts of Jeffcat ZF-10 from 0.25 to 2 parts of phosphorus compounds (see table)

(7) The mixture A and the isocyanate component were mixed with one another at an isocyanate index of 102 and charged to a closed mold, thus giving moldings with average density 380 g/L. The procedures for determining the values measured for mechanical properties were in accordance with the following standards.

(8) TABLE-US-00002 Property Dimension DIN standard Hardness Shore A 53505 Tensile strength MPa 1798 Tensile strain % 1798 Density g/mm.sup.3 845

(9) Heat-aging and of humid heat-aging here was carried out in accordance with DIN EN ISO 2440.

(10) TABLE-US-00003 TABLE 1 Mechanical properties of the resultant integral foams prior to and after aging over 7 days at 140 C. with addition of the respective phosphorus compounds P1 to P7 in the concentrations stated, in each case given in parts by weight, based on the total weight of the mixture A, and also without addition of phosphorus compounds (Ref.). P1 P2 P3 Property Ref. 0.5 pt. 0.5 pt. 0.5 pt. Tensile strength 0 values 2306 2412 2185 2586 MPa Final values 1201 2195 1838 2264 Change 48% 9% 16% 13% Tensile strain % 0 values 94 116 91 93 Final values 13 135 109 67 Change 86% +16% +20% 28% P4 P5 P6 P7 Property 1.0 pt. 1.0 pt. 1.0 pt. 1.0 pt. Tensile strength 0 values 2240 2346 2332 2397 MPa Final values 1955 1739 1919 1894 Change 13% 26% 18% 21% Tensile strain % 0 values 97 105 105 110 Final values 120 101 111 112 Change +24% 4% +6% +2%

(11) TABLE-US-00004 TABLE 2 Mechanical properties of the resultant integral foams prior to and after aging over 7 days at 140 C. with addition of the respective phosphorus compounds P8 to P12 in the concentrations stated, in each case given in parts by weight, based on the total weight of the mixture A. P8 P8 P9 P10 P11 P12 Property 0.5 pt. 1.0 pt. 1.0 pt. 1.0 pt. 1.0 pt. 1.0 pt. Tensile strength 0 values 2266 2272 2260 2297 2218 2222 MPa Final values 1131 1681 1373 1256 1338 1217 Change 51% 26% 39% 45% 40% 45% Tensile strain % 0 values 105 101 98 100 93 92 Final values 29 96 59 47 68 41 Change 73% 5% 40% 53% 27% 55%

(12) TABLE-US-00005 TABLE 3 Mechanical properties of the resultant integral foams prior to and after humid heat-aging over 3 cycles of 5 hours at 120 C. and 100% humidity in an autoclave with addition of the respective phosphorus compounds P1 to P4 in the concentrations stated, in each case given in parts by weight, based on the total weight of the mixture A, and also without addition of phosphorus compounds (Ref.). P2 P3 P4 Property Ref. 1.0 pt. 1.0 pt. 1.0 pt. Tensile strength 0 values 2306 2260 2337 2240 MPa Final values 1298 1520 1504 1801 Change 44% 33% 36% 20% Tensile strain % 0 values 94 102 93 97 Final values 74 139 144 148 Change 20% +36% +55% +52% P1 P2 Property 2.0 pt. 2.0 pt. Tensile strength 0 values 2115 2011 MPa Final values 1461 1640 Change 31% 18% Tensile strain % 0 values 116 97 Final values 117 147 Change +0% +51%

(13) TABLE-US-00006 TABLE 4 Mechanical properties of the resultant integral foams prior to and after aging over 7 days at 140 C. with addition of the respective phosphorus compounds P9 to P12 in the concentrations stated, in each case given in parts by weight, based on the total weight of the mixture A. P9 P10 P11 P12 Property 1.0 pt. 1.0 pt. 1.0 pt. 1.0 pt. Tensile strength 0 values 2260 2297 2218 2222 MPa Final values 1374 1341 1301 1084 Change 39% 42% 41% 51% Tensile strain % 0 values 98 100 93 92 Final values 117 123 109 92 Change +19% +23% +17% 0%

(14) Finally, steering wheels were produced starting from the mixtures A and from the isocyanate with use of respectively 0.5 part by weight of the phosphorus compounds P1, P2 and P3, based on the total weight of the mixture A, and also, as reference, without the use of phosphorus compound, and the steering wheels were aged at 140 C. for 7 days. The polyurethane in the steering wheel here without phosphorus compound is fragile and in part crumbles away, whereas the polyurethane of the steering wheels produced according to the invention is visually unchanged.