FLAME-RETARDANT PHOSPHORUS-FUNCTIONAL POLYETHER CARBONATE POLYOL AND METHOD FOR PRODUCTION THEREOF

Abstract

A process for preparing a phosphorus-functional polyethercarbonate polyol, comprising reacting a polyethercarbonate polyol having unsaturated groups with a phosphorus-functional compound of formula (Ia):

##STR00001##

wherein X=O or S; and wherein R.sup.1 and R.sup.2 are selected from the group consisting of C1-C22 alkyl, C1-C22 alkoxy, C1-C22 alkylsulfanyl, C6-C70 aryl, C6-C70 aryloxy, C6-C70 arylsulfanyl, C7-C70 aralkyl, C7-C70 aralkyloxy, C7-C70 aralkylsulfanyl, C7-C70 alkylaryl, C7-C70 alkylaryloxy, C7-C70 alkylarylsulfanyl, or wherein R.sup.1 and R.sup.2 are bridged to one another directly and/or via heteroatoms and are selected from the group consisting of C1-C22 alkylene, oxygen, sulfur, and NR.sup.5, wherein R.sup.5 is hydrogen, C1-C22 alkyl, C1-C22 acyl, C7-C22 aralkyl, or C6-C70 aryl radical. A process for preparing a phosphorus-functional polyurethane polymer is disclosed. Phosphorus-functional polyethercarbonate polyol, phosphorus-functional polyurethane polymer, flame-retardant adhesion promoter, filler-activator, flame retardant, flame-retardant coating, foam, sealing compound, thermoplastic, thermoset, rubber, and a moulded body are disclosed.

Claims

1. A process for preparing a phosphorus-functional polyethercarbonate polyol, comprising reacting a polyethercarbonate polyol having unsaturated groups with a phosphorus-functional compound of formula (Ia): ##STR00009## wherein X=O or S; and wherein R.sup.1 and R.sup.2 are selected from the group consisting of C1-C22 alkyl, C1-C22 alkoxy, C1-C22 alkylsulfanyl, C6-C70 aryl, C6-C70 aryloxy, C6-C70 arylsulfanyl, C7-C70 aralkyl, C7-C70 aralkyloxy, C7-C70 aralkylsulfanyl, C7-C70 alkylaryl, C7-C70 alkylaryloxy, C7-C70 alkylarylsulfanyl, or wherein R.sup.1 and R.sup.2 are bridged to one another directly and/or via heteroatoms and are selected from the group consisting of C1-C22 alkylene, oxygen, sulfur, and NR.sup.5, wherein R.sup.5 is hydrogen, C1-C22 alkyl, C1-C22 acyl, C7-C22 aralkyl or C6-C70 aryl radical.

2. The process as claimed in claim 1, wherein the phosphorus-functional compound of the formula (Ia) is a compound of the formula (Ib) ##STR00010## wherein A, B, and C are independently selected from the group consisting of a chemical bond, O, NH, N(C1-C10 alkyl), and N(C6-C14 aryl), wherein R.sup.3 and R.sup.4 are independently selected from the group consisting of C1-C10 alkyl, C1-C10 alkoxy, C6-C14 aryl, C6-C14 aryloxy, and C9-C17 aralkyl, and wherein n and m are independently 0, 1, 2, 3 or 4.

3. The process as claimed in claim 2, wherein R.sup.3 and R.sup.4 are selected from the group consisting of C1-C8 alkyl and C1-C8 alkoxy, and wherein n and m are independently 0 or 1.

4. The process as claimed in claim 1, wherein the phosphorus-functional compound is 9,10-dihydro-9-oxa-10-phosphaphenanthrene 10-oxide and/or butyl P-methylphosphinate.

5. The process as claimed in claim 1, wherein the polyethercarbonate polyol having unsaturated groups is selected from polyethercarbonate polyols having unsaturated groups or polyetherestercarbonate polyols having unsaturated groups.

6. The process as claimed in claim 1, wherein the polyethercarbonate polyol having unsaturated groups has been obtained by reacting a starter compound with one or more alkylene oxides, carbon dioxide, and one or more further monomers selected from the group of the alkylene oxides, the cyclic anhydrides of dicarboxylic acids, the lactones, lactides, and cyclic 6-membered carbonates, with the proviso that at least one of the further monomers used contains one or more CC double or triple bonds.

7. The process as claimed in claim 1, wherein a phosphorus content of the phosphorus-functional polyethercarbonate polyols is between 0.5% and 15% by weight.

8. The process as claimed in claim 1, wherein the polyethercarbonate polyol having unsaturated groups has been prepared by a process comprising the following steps: () initially charging an H-functional starter compound and a DMC catalyst, () optionally metering in an epoxide, () metering in (1) at least one epoxide, and (2) at least one epoxide, a cyclic anhydride of a dicarboxylic acid, a lactone, a lactide and/or a cyclic 6-membered carbonate having a double bond, and (3) carbon dioxide.

9. The process as claimed in claim 1, wherein the polyethercarbonate polyol having unsaturated groups is reacted with the phosphorus-functional compound of formula (Ia) at a temperature of not less than 100 C. and not more than 220 C.

10. The process as claimed in claim 1, wherein the polyethercarbonate polyol having unsaturated groups is reacted with the phosphorus-functional compound of formula (Ia) at a temperature of not less than 0 C. and not more than 100 C. and, in the reaction, a compound selected from the group of the basic catalysts or a compound selected from the group of the photoinitiators, peroxides, azo compounds, metal-activated peroxides and/or redox initiators is added.

11. A phosphorus-functional polyethercarbonate polyol obtainable by the process as claimed in claim 1.

12. A process for preparing a phosphorus-functional polyurethane polymer, wherein at least one phosphorus-functional polyethercarbonate polyol as claimed in claim 11 is reacted with one or more di- or polyisocyanates.

13. A phosphorus-functional polyurethane polymer obtainable by a process as claimed in claim 12.

14. A product comprising the phosphorus-functional polyethercarbonate polyol as claimed in claim 11, the product selected from the group consisting of a flame-retardant adhesion promoter, a filler-activator, a flame retardant, a flame-retardant coating, a foam, a sealing compound, a thermoplastic, a thermoset, or a rubber.

15. A moulded body having a flame-retardant layer comprising a phosphorus-functional polyurethane polymer as claimed in claim 13.

16. A product comprising the phosphorus-functional polyurethane polymer as claimed in claim 13, the product selected from the group consisting of a flame-retardant adhesion promoter, a filler-activator, a flame retardant, a flame-retardant coating, a foam, a sealing compound, a thermoplastic, a thermoset, or a rubber.

Description

EXAMPLES

[0180] H-Functional Starter Substance (Starter) Used:

[0181] PET-1 difunctional poly(oxypropylene)polyol having an OH number of 112 mg.sub.KOH/g

[0182] Alkylene oxide bearing no double bonds used:

[0183] PO propylene oxide

[0184] Comonomer Used:

[0185] MA maleic anhydride, containing electron-deficient double bonds

[0186] AGE allyl glycidyl ether, containing electron-rich double bonds

[0187] Phosphorus Compound Used:

[0188] DOPO 9,10-dihydro-9-oxa-phosphaphenanthrene 10-oxide

[0189] Free-radical initiator used:

[0190] Irgacure 819 bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide

[0191] The DMC catalyst was prepared according to example 6 of WO-A 01/80994.

[0192] The polymerization reactions were conducted in a 300 ml Parr pressure reactor. The pressure reactor used in the examples had a height (internal) of 10.16 cm and an internal diameter of 6.35 cm. The reactor was equipped with an electrical heating jacket (maximum heating power 510 watts). The counter-cooling consisted of an immersed tube of external diameter 6 mm which had been bent into a U shape and which projected into the reactor up to 5 mm above the base, and through which cooling water flowed at about 10 C. The water flow was switched on and off by means of a magnetic valve. In addition, the reactor was equipped with an inlet tube and a thermal sensor of diameter 1.6 mm, which projected into the reactor up to 3 mm above the base.

[0193] The heating power of the electrical heating jacket during the activation [first activation stage] averaged about 20% of the maximum heating power. As a result of the adjustment, the heating power varied by 5% of the maximum heating power. The occurrence of increased evolution of heat in the reactor, brought about by the rapid reaction of propylene oxide during the activation of the catalyst [second activation stage], was observed via reduced heating power of the heating jacket, engagement of the counter-cooling, and, optionally, a temperature increase in the reactor.

[0194] The occurrence of evolution of heat in the reactor, brought about by the continuous reaction of propylene oxide during the reaction [polymerization stage], led to a fall in the power of the heating jacket to about 8% of the maximum heating power. As a result of the adjustment, the heating power varied by 5% of the maximum heating power.

[0195] The hollow shaft stirrer used in the examples was a hollow shaft stirrer in which the gas was introduced into the reaction mixture via a hollow shaft in the stirrer. The stirrer body attached to the hollow shaft comprised four arms, had a diameter of 35 mm and a height of 14 mm. Each end of the arm had two gas outlets of 3 mm in diameter attached to it. The rotation of the stirrer gave rise to a reduced pressure such that the gas present above the reaction mixture (CO.sub.2 and possibly alkylene oxide) was drawn off and introduced through the hollow shaft of the stirrer into the reaction mixture.

[0196] The impeller stirrer used in some examples was a pitched blade turbine in which a total of two stirrer levels each having four stirrer paddles (45) which had a diameter of 35 mm and a height of 10 mm were mounted at a distance of 7 mm on the stirrer shaft.

[0197] a) The terpolymerization of propylene oxide, allyl glycidyl ether and CO.sub.2 results not only in the cyclic propylene carbonate but also in the polyethercarbonate polyol containing firstly polycarbonate units shown in formula (Xa)

##STR00007##

[0198] and secondly polyether units shown in formula (Xb)

##STR00008##

[0199] In the case of incorporation of cyclic anhydrides into the polymer chain, this additionally contains ester groups.

[0200] The reaction mixture was characterized by NMR spectroscopy and gel permeation chromatography.

[0201] The ratio of the amount of cyclic propylene carbonate to polyethercarbonate polyol (selectivity; c/a ratio) and the proportion of unconverted monomers (propylene oxide R.sub.PO, allyl glycidyl ether RAGE in mol %) were determined by means of .sup.1H NMR spectroscopy. For this purpose, a sample of each reaction mixture obtained after the reaction was dissolved in deuterated chloroform and measured on a Bruker spectrometer (AV400, 400 MHz).

[0202] Subsequently, the reaction mixture was diluted with dichloromethane (20 ml) and the solution was passed through a falling-film evaporator. The solution (0.1 kg in 3 h) ran downwards along the inner wall of a tube of diameter 70 mm and length 200 mm which had been heated externally to 120 C., in the course of which the reaction mixture was distributed homogeneously as a thin film on the inner wall of the falling-film evaporator in each case by three rollers of diameter 10 mm rotating at a speed of 250 rpm. Within the tube, a pump was used to set a pressure of 3 mbar. The reaction mixture which had been purified to free it of volatile constituents (unconverted epoxides, cyclic carbonate, solvent) was collected in a receiver at the lower end of the heated tube.

[0203] The molar ratio of carbonate groups to ether groups in the polyethercarbonate polyol (/b ratio) and the molar proportion of comonomers incorporated into the polymer were determined by means of NMR spectroscopy. For this purpose, a sample of each purified reaction mixture was dissolved in deuterated chloroform and measured on a Bruker spectrometer (AV400, 400 MHz).

[0204] The relevant resonances in the .sup.1H NMR spectrum (based on TMS=0 ppm) which were used for integration are as follows:

TABLE-US-00001 Area corresponding to number of H Signal Shift in ppm Assignment atoms I1 1.10-1.17 CH.sub.3 group of the polyether units 3 I2 1.25-1.34 CH.sub.3 group of the polycarbonate units 3 I3 1.45-1.48 CH.sub.3 group of the cyclic carbonate 3 I4 2.95-3.00 CH groups of the free propylene oxide 1 not consumed by reaction I5 5.83-5.94 CH group of the double bond obtained 1 in the polymer via the incorporation of allyl glycidyl ether I6 6.22-6.29 CH group of the double bond obtained 2 in the polymer via the incorporation of maleic anhydride I7 7.03-7.04 CH group for free maleic anhydride not 2 consumed by reaction I8 2.59-2.66 & CH group of the DOPO incorporated 2 2.75-2.78 into the polymer I9 1.74-1.84 CH group of the DOPO incorporated 2 into the polymer

[0205] The figures reported are the molar ratio of the amount of cyclic propylene carbonate to carbonate units in the polyethercarbonate polyol or polyetherestercarbonate polyol (selectivity c/a) and the molar ratio of carbonate groups to ether groups in the polyethercarbonate polyol or polyetherestercarbonate polyol (/b), and the proportions of the unconverted propylene oxide (in mol %) and maleic anhydride (in mol %).

[0206] Taking account of the relative intensities, the values were calculated as follows:

[0207] Molar ratio of the amount of cyclic propylene carbonate to carbonate units in the polyethercarbonate polyol or polyetherestercarbonate polyol (selectivity c/a):

c/a=I3/I2(XI)

[0208] Molar ratio of carbonate groups to ether groups in the polyethercarbonate polyol or polyetherestercarbonate polyol (a/b):

a/b=I2/I1(XII)

[0209] The molar proportion of the unconverted propylene oxide (R.sub.PO in mol %) based on the sum total of the amount of propylene oxide used in the activation and the copolymerization, calculated by the formula:

R.sub.PO=[(I4/1)/((I1/3)+(I2/3)+(I3/3)+(I4/1))]100%(XIII)

[0210] The figures for the proportions A are based hereinafter on polyetherestercarbonate polyols that have been obtained using maleic anhydride as comonomer.

[0211] The molar proportion of the unconverted maleic anhydride (R.sub.MA in mol %) based on the sum total of the amount of maleic anhydride used in the activation and the copolymerization is calculated by the formula:

R.sub.MA=[(I6/2)/((I6/2)+(I7/2))]100%(XIV)

[0212] Proportion of carbonate units in the repeat units of the polyetherestercarbonate polyol:

A.sub.carborate[(I2/3)/((I1/3)+(I2/3)+(I6/2))]100%(XV)

[0213] Proportion of the double bonds which result via the incorporation of the maleic anhydride in the repeat units of the polyetherestercarbonate polyol:

A.sub.double bond=[(I6/2)/((I1/3)+(I2/3)+(I6/2))]100%(XVI)

[0214] Proportion of DOPO units in the repeat units of the polyetherestercarbonate polyol:

A.sub.DOPO=[(I8/2)/((I1/3)+(I2/3)+(I8/2)+(I6))]100%(XVII)

[0215] The figures for the proportions B are based hereinafter on polyethercarbonate polyols that have been obtained using allyl glycidyl ether as comonomer.

[0216] The proportion of carbonate units in the repeat units of the polyethercarbonate polyol:

B.sub.carbonate=[(I2/3)/((I1/3)+(I2/3)+(I5/1))]100%(XVIII)

[0217] The proportion of double bonds resulting from the incorporation of the allyl glycidyl ether in the repeat units of the polyethercarbonate polyol:

B.sub.double bond=[(I5)/((I1/3)+(I2/3)+(I5/1))]100%(XIX)

[0218] The proportion of DOPO units in the repeat units of the polyethercarbonate polyol:

B.sub.DOPO=[(I9/2)/((I1/3)+(I2/3)+(I9/2)+(I5))]100%(XX)

Preparation of the Polyethercarbonate Polyols

[0219] Polyethercarbonate Polyol A:

[0220] Terpolymerization of propylene oxide, maleic anhydride (9.5 mol %) and CO.sub.2

[0221] [First Activation Stage]

[0222] A 970 ml pressure reactor equipped with a gas introduction stirrer was charged with a mixture of DMC catalyst (104 mg) and PET-1 (130 g) and this initial charge was stirred at 130 C. for 30 minutes under a partial vacuum (50 mbar), with argon being passed through the reaction mixture.

[0223] [Second Activation Stage]

[0224] Following injection of 15 bar of CO.sub.2, at which a slight drop in temperature was observed, and following re-establishment of a temperature of 130 C., 13.0 g of a monomer mixture (15 wt % of maleic anhydride, corresponding to 9.5 mol %, in solution in propylene oxide) were metered in by means of an HPLC pump (1 ml/min). The reaction mixture was stirred (800 rpm) at 130 C. for 20 min. The addition of 13.0 g of a monomer mixture was repeated a second and third time.

[0225] [Polymerization Stage]

[0226] After cooling to 100 C. had taken place, a further 186.0 g of the monomer mixture (15% by weight of maleic anhydride, corresponding to 9.5 mol %) were metered in via an HPLC pump (6 ml/min), keeping the CO.sub.2 pressure constant at 15 bar. The reaction mixture was then stirred at 100 C. for a further 2 h. The reaction was halted by cooling of the reactor with ice-water.

[0227] Product Properties:

[0228] The resulting mixture was free of the propylene oxide (R.sub.PO=0%) and maleic anhydride (R.sub.MA=0%) monomers used.

TABLE-US-00002 Selectivity c/a 0.04 a/b 0.27 A.sub.carbonate in % 21.2 A.sub.double bond in % 5.7 Molecular weight in M.sub.n 4175 g/mol Polydispersity 1.2 OH number in mg.sub.KOH/g 38.0

Example 1: Preparation of DOPO-Containing Polyethercarbonate Polyol

[0229] In a 250 ml two-neck flask, DOPO (12.01 g, 0.06 mol) and DBU (1.69 g, 0.01 mol) were dissolved in THF (40 ml). Subsequently, a further solution of polyethercarbonate polyol A (50.0 g) in THF (130 ml) was prepared. This polyethercarbonate polyol solution was transferred into the two-neck flask with the aid of a dropping funnel. The reaction mixture was stirred for one hour. The solvent was then removed under reduced pressure.

[0230] Product Properties:

TABLE-US-00003 A.sub.DOPO in % 4.84 (1.95 wt % of P) Molecular weight in M.sub.n 3921 g/mol Polydispersity 1.3 OH number in mg.sub.KOH/g 34.3

Preparation of the Polyurethanes

Example 2: Preparation of a Polyurethane from Phosphorus-Containing Polyethercarbonate Polyol

[0231] For the preparation of phosphorus-containing polyurethane (sample PU-1), the DOPO-containing polyethercarbonate polyol from example 1 (8.2 g) was admixed with an equimolar amount of aliphatic polyisocyanate (HDI trimer, Desmodur N3300, 1.0 g) and 1000 ppm of dibutyltin laurate. The sample was cured on a planar metal plate. Subsequently, the phosphorus-containing polyurethane sample (1.5 g, 20152 mm) was exposed to a flame for 10 s in order to test fire resistance.

Example 3 (Comp.): Preparation of a Polyurethane from Polyethercarbonate Polyol

[0232] For the preparation of polyurethane without phosphorus (sample PU-2), the polyethercarbonate polyol A (7.4 g) was admixed with an equimolar amount of aliphatic polyisocyanate (HDI trimer, Desmodur N3300, 1.0 g) and 1000 ppm of dibutyltin laurate. The sample was cured on a planar metal plate. Subsequently, the polyurethane sample (1.5 g, 20152 mm) was exposed to a flame for 10 s in order to test fire resistance.

[0233] Results of the Flame Test

[0234] The results from the flame test are given in the table below for the polyurethane sample from example 2 and the polyurethane sample from comparative example 3. The phosphorus content reported is based on the polyurethane sample.

TABLE-US-00004 Appearance of the sample during Appearance of Phosphorus the duration of Appearance of the the sample 30 s content flame contact of sample 1 s after after flame Fire Example (wt %) 10 s flame contact contact resistance 2 1.7 The flame height No flame visible No flame Flame- is 26 mm visible retardant The surface of The surface of the The surface of the sample has sample has melted the sample has melted melted 3 The flame height The sample No flame Flammable (comp.) is 30 mm continues to burn visible independently with a flame height of 35 mm Burning droplets Burning droplets The sample has form form visibly melted Comp. comparative example

[0235] Comparison

[0236] The comparison of the results from example 2 with comparative example 3 shows that the phosphorus-containing polyurethane sample has much higher fire resistance.

Preparation of the Polyethercarbonate Polyols

[0237] Polyethercarbonate polyol B: Terpolymerization of propylene oxide, allyl glycidyl ether (9.5 mol %) and CO.sub.2

[0238] [First Activation Stage]

[0239] A 970 ml pressure reactor equipped with a gas introduction stirrer was charged with a mixture of DMC catalyst (48 mg) and PET-1 (80 g) and this initial charge was stirred at 130 C. for 30 minutes under a partial vacuum (50 mbar), with argon being passed through the reaction mixture.

[0240] [Second Activation Stage]

[0241] Following injection of 15 bar of CO.sub.2, at which a slight drop in temperature was observed, and following re-establishment of a temperature of 130 C., 8.0 g of a monomer mixture (16.7% by weight of allyl glycidyl ether [corresponding to 9.5 mol %] in solution in propylene oxide) were metered in by means of an HPLC pump (1 ml/min). The reaction mixture was stirred (800 rpm) at 130 C. for 20 min. The addition of 8.0 g of a monomer mixture was repeated a second and third time.

[0242] [Polymerization Stage]

[0243] After cooling to 100 C. had taken place, a further 136.0 g of the monomer mixture (16.7% by weight of allyl glycidyl ether, corresponding to 9.5 mol %) were metered in via an HPLC pump (1 ml/min), keeping the CO.sub.2 pressure constant at 15 bar. The reaction mixture was then stirred at 100 C. for a further 2 h. The reaction stopped by cooling the reactor with ice-water.

[0244] Product Properties:

[0245] The resulting mixture was free from the propylene oxide and allyl glycidyl ether monomers used.

TABLE-US-00005 Selectivity c/a 0.07 a/b 0.19 B.sub.carbonate in % 14.9 B.sub.double bond in % 5.5 Molecular weight in M.sub.n 4678 g/mol Polydispersity 1.4 OH number in mg.sub.KOH/g 36.3

Example 4: Preparation of DOPO-Containing Polyethercarbonate Polyol

[0246] The polyethercarbonate polyol B (10.0 g) and DOPO (2.2 g) were mixed and heated to 120 C. On completion of dissolution of the DOPO, the temperature was adjusted to 80 C. Subsequently, the Irgacure 819 photoinitiator (100 mg) was introduced into the reaction mixture. The solution was irradiated with UV light (22 W/cm.sup.2) for 2 min. The product prepared was analyzed by means of NMR spectroscopy and GPC.

[0247] Product Properties:

TABLE-US-00006 B.sub.DOPO in % 3.72 (1.53 wt % of P) Molecular weight in M.sub.n 5288 g/mol Polydispersity 2.3 OH number in mg.sub.KOH/g 30.3

Preparation of the Polyurethanes

Example 5: Preparation of a Polyurethane from Phosphorus-Containing Polyethercarbonate Polyol

[0248] For the preparation of phosphorus-containing polyurethane (PU-3), the DOPO-containing polyethercarbonate polyol from example 4 (9.3 g) was admixed with an equimolar amount of aliphatic polyisocyanate (HDI trimer, Desmodur N3300, 1.0 g) and 1000 ppm of dibutyltin laurate. The sample was cured on a planar metal plate. Subsequently, the phosphorus-containing polyurethane sample (1.5 g, 20152 mm) was exposed to a flame for 10 s in order to test fire resistance.

Example 6 (Comp.): Preparation of a Polyurethane from Polyethercarbonate Polyol

[0249] For the preparation of polyurethane without phosphorus (PU-4), the polyethercarbonate polyol B (7.7 g) was admixed with an equimolar amount of aliphatic polyisocyanate (HDI trimer, Desmodur N3300, 1.0 g) and 1000 ppm of dibutyltin laurate. The sample was cured on a planar metal plate. Subsequently, the polyurethane sample (1.5 g, 20152 mm) was exposed to a flame for 10 s in order to test fire resistance.

[0250] Results of the Flame Test

[0251] The results from the flame test are given in the table below for the polyurethane sample from example 5 and the polyurethane sample from comparative example 6. The phosphorus content reported is based on the polyurethane sample.

TABLE-US-00007 Appearance of the Appearance of Phosphorus sample during the Appearance of the the sample 30 s content duration of flame sample 1 s after after flame Fire Example (wt %) contact of 10 s flame contact contact resistance 7 1.4 The flame height is No flame visible No flame visible Flame- 26 mm retardant The surface of the The surface of the The surface of sample has melted sample has melted the sample has melted 6 (comp.) The flame height is The sample No flame visible Flammable 30 mm continues to burn independently with a flame height of 35 mm Burning droplets form Burning droplets The sample has form visibly melted Comp. comparative example

[0252] Comparison

[0253] The comparison of the results from example 5 with comparative example 6 shows that the phosphorus-containing polyurethane sample has much higher fire resistance.