METHOD FOR PRODUCING A POLYMER WHICH CONTAINS DOUBLE BONDS AS AN ELASTOMER PRECURSOR

Abstract

The present invention relates to a method for producing an organooxysilyl-crosslinked polymer by reacting a polyether carbonate polyol which contains carbon-carbon double bonds with a polysiloxane compound in the presence of a suitable catalyst. Suitable polysiloxane compounds have at least two Si—H bonds. This invention also relates to organooxysilyl-crosslinked polymers which are formed by this process.

Claims

1. A process for preparing an organooxysilyl-crosslinked polymer, comprising reacting a polyethercarbonate polyol containing carbon-carbon double bonds with a polysiloxane compound in the presence of a catalyst (A), wherein the polysiloxane compound has at least two Si—H bonds.

2. The process as claimed in claim 1, wherein the polysiloxane compound comprises an α,ω-polysiloxane compound.

3. The process as claimed in claim 2, wherein the α,ω-polysiloxane compound corresponds to a structure of formula (I): ##STR00005## wherein 1≥a≤3; 1≥h≤3; a+b+c=3, f+g+h=3; R.sup.1, R.sup.2, R.sup.5, and R.sup.6 each independently represent=an alkyl radical, an aryl radical, or a cycloalkyl radical; R.sup.3 represents O—SiR.sup.7R.sup.8; wherein, R.sup.7, and R.sup.8 each independently =represent an alkyl radical, an aryl radical, or a cycloalkyl radical; d=represents a number from 1 to 100; R.sup.4=represents O—SiR.sup.9R.sup.10; wherein: R.sup.9, and R.sup.10 each independently =represent a hydrogen atom, an alkyl, radical, an aryl radical, or a cycloalkyl radical; and e=represents a number from 1 to 100.

4. The process as claimed in claim 3, wherein R.sup.1, R.sup.2, R.sup.3, R.sup.4 R.sup.5 each represent a methyl radical; R.sup.7, and R.sup.8 each represent a methyl radical; R.sup.9 represents hydrogen; R.sup.10 represents a methyl radical; d represents a number from 10 to 60; and e represents a number from 10 to 60.

5. The process as claimed in claim 1, wherein the polyethercarbonate polyol containing carbon-carbon double bonds is obtainable by addition of an alkylene oxide, at least one monomer containing carbon-carbon double bonds and CO2 onto an H-functional starter compound in the presence of a double metal cyanide catalyst.

6. The process as claimed in claim 5, wherein the molar ratio of the saturated alkylene oxides used to the at least one further monomer containing carbon-carbon double bonds is from 55.0 mol % to 99.5 mol %.

7. The process as claimed in claim 5, wherein the carbon-carbon double bond-containing monomer is selected from at least one of the monomers from one or more of the groups consisting of (a) allyl glycidyl ether, vinylcyclohexene oxide, cyclooctadiene monoepoxide, cyclododecatriene monoepoxide, butadiene monoepoxide, isoprene monoepoxide, limonene oxide, 1,4-divinylbenzene monoepoxide, 1,3-divinylbenzene monoepoxide, glycidyl esters of unsaturated fatty acids, such as oleic acid, linoleic acid, conjuene fatty acid, or linolenic acid, partly epoxidized fats and oils, such as partly epoxidized soya oil, linseed oil, rapeseed oil, palm oil or sunflower oil, and/or mixtures thereof; (b) an alkylene oxide with a double bond which corresponds to the general formula (IX): ##STR00006## wherein: R.sub.1 to R.sub.3 each independently represent H, halogen, a substituted or an unsubstituted C.sub.1-C.sub.22 alkyl radical or a substituted or an unsubstituted C.sub.6-C 12 aryl radical; (c) a cyclic anhydride corresponding to the formula (X), (XI) or (XII): ##STR00007## wherein R.sub.1 to R.sub.10 each independently represent H, halogen, a substituted or n unsubstituted C.sub.1-C.sub.22 alkyl radical, or a substituted or an unsubstituted C.sub.6-C.sub.12 aryl; and (d) 4-cyclohexene-1,2-dioic anhydride, 4-methyl-4-cyclohexene-1,2-dioic anhydride, 5,6-norbomene-2,3-dioic anhydride, allyl-5,6-norbomene-2,3-dioic anhydride, dodecenylsuccinic anhydride, tetradecenylsuccinic anhydride, hexadecenylsuccinic anhydride and octadecenylsuccinic anhydride.

8. The process as claimed in claim 7, wherein the carbon-carbon double bond-containing monomer is selected from at least one of the monomers from one or more of the groups consisting of (a) allyl glycidyl ether, vinylcyclohexene oxide and limonene oxide, (b) glycidyl acrylate and glycidyl methacrylate, (c) maleic anhydride and itaconic anhydride and (d) 4-cyclohexene-1,2-dioic anhydride and 5,6-norbomene-2,3-dioic anhydride.

9. The process as claimed in claim 1, wherein the polyethercarbonate polyol containing carbon-carbon double bonds has a CO.sub.2 content of 0.5% by weight to 50% by weight.

10. The process as claimed in claim 1, wherein the molar ratio of the carbon-carbon double bonds in the polyethercarbonate polyol to the Si—H bonds of the polysiloxane compound is from 1:10 to 10:1.

11. The process as claimed in claim 1, the catalyst (A) is a hydrosilylation catalyst.

12. The process as claimed in claim 11, wherein the hydrosilylation catalyst is one or more compound(s) and is selected from the group consisting of Karstedt catalysts, Speier catalysts, elemental platinum and elemental platinum on a support of activated carbon or alumina.

13. The process as claimed in claim 11, wherein the hydrosilylation catalyst is one or more compound(s) and is selected from the group consisting of platinum(0)-1,3-divinyl-1,1,3,3-tetramethyldisiloxane, hexachloroplatinic acid, pentamethylcyclopentadienyl-tris(acetonitrile)-ruthenium(II) hexafluorophosphate, bis(1,5-cyclooctadiene)rhodium(I) tetrafluoroborate, (bicyclo[2.2.1]hepta-2,5-diene)rhodium(I) chloride dimer, tris(triphenylphosphine)rhodium(I) chloride, benzenedichlororuthenium(II) dimer, dichloro(p-cymene)ruthenium(II) dimer and benzylidenebis(tricyclohexylphosphine)dichlororuthenium(II).

14. An organooxysilyl-crosslinked polymer obtainable by a process as claimed in claim 1, wherein the organooxysilyl end group has a number-average molecular weight M.sub.n of ≥500 g/mol to ≤100 000 g/mol, which has been determined by means of GPC.

Description

EXAMPLES

[0177] PET-1 difunctional poly(oxypropylene)polyol having an OH number of 112 mg.sub.KOH/g

[0178] PO propylene oxide from Chemgas, purity>99%

[0179] AGE allyl glycidyl ether from Sigma Aldrich, purity>99%

[0180] MA maleic anhydride from Sigma Aldrich, purity>99%

[0181] The DMC catalyst was prepared according to example 6 of WO-A 01/80994.

[0182] Polysiloxane Used [0183] Polysiloxane-1: polysiloxane from Momentive, silane (Si—H) content 0.55 mmol/g; Mn of 900 g/mol [0184] Polysiloxane-2:polysiloxane from Momentive, silane (Si—H) content 3.80 mmol/g; Mn of 1280 g/mol

[0185] Catalysts Used

[0186] Karstedt catalyst (2.0% by weight of Pt in xylene) from Sigma-Aldrich

[0187] Polyoxyalkylene Polyols Used

[0188] Preparation of a Difunctional Polyoxyalkylene Polyol (Polyol-1) Containing Electron-Rich Double Bonds

[0189] 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. 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 9.3 mol %] in solution in propylene oxide) was 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 the monomer mixture was repeated a second and third time. After cooling to 100° C., a further 136.0 g of the monomer mixture (16.7% by weight of allyl glycidyl ether) was 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 1 h. The reaction was halted by cooling of the reactor with ice-water.

[0190] Characterization of the polyoxyalkylene polyol obtained by the methods specified in WO 2015032737 A1 gave an OH number of 27.2 mg.sub.KOH/g, a CO.sub.2 content of 12.79% by weight, a molecular weight M.sub.n of 4566 g/mol, a polydispersity index (PDI) of 1.33 and a double bond content of 2.2% by weight.

[0191] Preparation of a Difunctional Polyoxyalkylene Polyol (Polyol-2) Containing Electron-Deficient Double Bonds

[0192] A 970 ml pressure reactor equipped with a gas introduction stirrer was charged with a mixture of DMC catalyst (70 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. 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., 80 g of a monomer mixture (11.0% by weight of maleic anhydride [corresponding to 6.8 mol %] in solution in propylene oxide) was 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 the monomer mixture was repeated a second and third time. After cooling to 100° C., a further 246.0 g of the monomer mixture (11.0% by weight of maleic anhydride in solution in propylene oxide) was 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 1 h. The reaction was halted by cooling of the reactor with ice-water.

[0193] Characterization of the polyoxyalkylene polyol obtained by the methods specified in WO 2015032737 A1 gave an OH number of 22.4 mg.sub.KOH/g, a CO.sub.2 content of 15.92% by weight, a molecular weight M.sub.n of 5009 g/mol, a PDI of 1.9 and a double bond content of 2.2% by weight.

[0194] Methods:

[0195] For rheological determination of the gel point, a sample of the polyethercarbonate polyol was admixed with a substoichiometric amount of a polysiloxane and platinum(0)-1,3-divinyl-1,1,3,3-tetramethyldisiloxane. Shear characteristics were analyzed on a Physica MCR501 from Anton Paar equipped with PP15 measurement system. The complex moduli G′ (storage modulus) and G″ (loss modulus) were determined in an oscillation measurement at 90° C. and a frequency of 1 Hz, using a plate/plate configuration with a plate diameter of 15 mm, a plate-to-plate distance of 1 mm, and a 10 percent deformation. The gel point was defined as the juncture when the storage modulus and loss modulus were equal.

[0196] For the rheological determination of the gel time, a sample of the polyethercarbonate polyol was admixed with an equimolar amount of a polyisocyanate (diisocyanate and/or triisocyanate) and dibutyltin laurate (1% by weight). The complex moduli G′(storage modulus) and G″ (loss modulus) were determined in an oscillation measurement at 60° C. and a frequency of 1 Hz, using a plate/plate configuration with a plate diameter of 15 mm, a plate-to-plate distance of 1 mm, and a 10 percent deformation. The gel point was defined as the juncture at which storage modulus (G′) and loss modulus (G″) are equal (G′/G″=1). For determination of the storage modulus (G′) after 2 hours, the value of the storage modulus attained at this time, measured in Pa, was read off.

[0197] For the rheological determination of the adhesion fracture energy (bonding force), a sample of the prepolymer was applied to the measurement plate of the rheometer. The breaking force (FN) and elongation at break (d) were determined in a bonding force measurement at 30° C., using a plate-plate configuration having a plate diameter of 15 mm and a plate-to-plate distance of 0.8 mm. The sample was first pressed at a compression force of 10 N. Subsequently, the upper plate was raised at a speed of −2.5 mm/s and the breaking force (FN) was determined over the incremental distances di until the sample broke. The adhesion fracture energy was calculated by the following formula, where “r” is the radius of the upper plate (r=7.5 mm), and is reported in N/mm.

E.sub.ad=Σ.sub.i(F.sub.N,i×d.sub.i/π)/(r.sup.2×π)

[0198] The infrared (IR) spectroscopy measurements were effected on a Bruker Alpha-P FT-IR spectrometer; the measurements were effected in pure substance; the wavenumber of the maximum of the signal for the C=C stretch vibration is reported.

[0199] The double bond content of the prepolymers is found as the quotient of the reported double bond content of the polyethercarbonate polyols used (reported in C2H4 equivalents per unit mass of polyethercarbonate polyol), based on the total mass of the reactants used (polyethercarbonate polyol, isocyanate mixture, catalyst), and is reported in C2H4 equivalents per unit mass of prepolymer.

Example 1: Preparation of an Elastomer Precursor Using an Unsaturated Polyethercarbonate Polyol (Polyol-1) with 2.2% by Weight of Double Bonds and Polysiloxane-1 in a Molar Ratio of 4 Double Bonds (C═C):1 Silane (Si—H)

[0200] In a crimp-cap bottle, polysilane 1 (38 g) and platinum(0)-1,3-divinyl-1,1,3,3-tetramethyldisiloxane (19 mg) were blended with one another (mixture 1).

[0201] In a weighing boat, polyol-1 (500 mg) and mixture 1 (380 mg) were mixed. Subsequently, the mixture was applied to the measurement system of the rheometer and the curing characteristics were monitored at 90° C. over 120 min.

Example 2: Preparation of an Elastomer Precursor Using an Unsaturated Polyethercarbonate Polyol (Polyol-1) with 2.2% by Weight of Double Bonds (C═C) and Polysiloxane-2 in a Molar Ratio of 4 Double Bonds:1 Silane (Si—H)

[0202] In a crimp-cap bottle, polysiloxane 2 (5.6 g) and platinum(0)-1,3-divinyl-1,1,3,3-tetramethyldisioxane (19 mg) were blended with one another (mixture 2).

[0203] In a weighing boat, polyol-1(500 mg) and mixture 2 (56 mg) were mixed. Subsequently, the mixture was applied to the measurement system of the rheometer and the curing characteristics were monitored at 90° C. over 120 min.

Example 3 (Comp.): Preparation of an Elastomer Precursor Using an Unsaturated Polyethercarbonate Polyol (Polyol-1) with 2.2% by Weight of Double Bonds and Sulfur in a Molar Ratio of 4 Double Bonds (C═C):1 S.SUB.8 .Unit

[0204] In a weighing boat, polyol-1 (500 mg) and elemental sulfur (50 mg) were mixed. Subsequently, the mixture was applied to the measurement system of the rheometer and the curing characteristics were monitored at 90° C. over 120 min.

[0205] Analysis by means of IR spectroscopy showed the characteristic signal for double bonds at 1645 cm.sup.−1.

Example 4 (Comp.): Preparation of an Elastomer Precursor Using an Unsaturated Polyethercarbonate Polyol (Polyol-1) with 2.2% by Weight of Double Bonds (C═C)

[0206] Polyol-1 (500 mg) supplemented with 60 ppm of catalyst was applied to the measurement system of the rheometer and the curing characteristics were monitored at 90° C. over 120 min.

[0207] Analysis by means of IR spectroscopy showed the characteristic signal for double bonds at 1645 cm.sup.−1.

TABLE-US-00001 TABLE 1 Molar G′ Polyether- ratio of Gel after Ex- carbonate (C═C) to point 2 h ample polyol Crosslinker (Si—H).sup.a) [s] [Pa] 1 Polyol-1 Polysiloxane- 4:1 1230 3380 1 2 Polyol-1 Polysiloxane- 4:1 <60 4900 2 3 Polyol-1 Sulfur No curing No curing 0 (comp.) 4 Polyol-1 — No curing No curing 0 (comp.) Comp.: comparative example; .sup.a)molar ratio of the carbon-carbon double bonds (C═C) in the polyethercarbonate polyol to the Si—H bonds of the polysiloxane compound

[0208] Examples 1-4 show that the crosslinking of electron-rich polyethercarbonate polyols with substoichiometrically of a polysiloxane leads to the construction of a 3D network. In this context, the reaction with siloxane-richer compounds (examples 1-2) leads to a more stable network within a shorter time. It was not possible to observe reaction with sulfur as crosslinker or without any crosslinker. Without siloxane compounds, the polyol 1 does not cure (comparative examples 3-4).

Example 5: Preparation of an Elastomer Precursor Using an Unsaturated Polyethercarbonate Polyol (Polyol-1) with 2.2% by Weight of Double Bonds and Polysiloxane-1 in a Molar Ratio of 2 Double Bonds (C═C):1 Silane (Si—H)

[0209] In a crimp-cap bottle, polysiloxane 1 (38 g) and platinum(0)-1,3-divinyl-1,1,3,3-tetramethyldisioxane (9.5 mg) were blended with one another (mixture 3).

[0210] In a weighing boat, polyol-1 (500 mg) and mixture 3 (760 mg) were mixed. Subsequently, the mixture was applied to the measurement system of the rheometer and the curing characteristics were monitored at 90° C. over 120 min.

Example 6: Preparation of an Elastomer Precursor Using an Unsaturated Polyethercarbonate Polyol (Polyol-1) with 2.2% by Weight of Double Bonds and Polysiloxane-2 in a Molar Ratio of 2 Double Bonds (C═C):1 Silane (Si—H)

[0211] In a crimp-cap bottle, polysiloxane 2 (5.6 g) and platinum(0)-1,3-divinyl-1,1,3,3-tetramethyldisioxane (9.5 mg) were blended with one another (mixture 4).

[0212] In a weighing boat, polyol-1 (500 mg) and mixture 4 (120 mg) were mixed. Subsequently, the mixture was applied to the measurement system of the rheometer and the curing characteristics were monitored at 90° C. over 120 min.

TABLE-US-00002 TABLE 2 Molar G′ Polyether- ratio of Gel after Ex- carbonate (C═C) to point 2 h ample polyol Crosslinker (Si—H).sup.a) [s] [Pa] 5 Polyol-1 Poly siloxane- 2:1 <60 8800 1 6 Polyol-1 Poly siloxane- 2:1 <60 930 2 4 Polyol-1 — No curing No curing 0 (comp.) Comp.: comparative example; .sup.a)molar ratio of the carbon-carbon double bonds (C═C) in the polyethercarbonate polyol to the Si—H bonds of the polysiloxane compound

[0213] Examples 5-6 show that the change in the ratio between double bond and siloxane leads to a different network density and reaction time. Given double the silane content, there is a disproportionate rise in the stability of the network formed, while there is a distinct fall in the reaction time.

Example 7: Preparation of an Elastomer Precursor Using an Unsaturated Polyethercarbonate Polyol (Polyol-1) with 2.2% by Weight of Double Bonds and Polysiloxane-1 in a Molar Ratio of 1 Double Bonds (C═C):1 Silane (Si—H)

[0214] In a crimp-cap bottle, polysiloxane 1 (38 g) and platinum(0)-1,3-divinyl-1,1,3,3-tetramethyldisioxane (4.5 mg) were blended with one another (mixture 5).

[0215] In a weighing boat, polyol-1(500 mg) and mixture 5 (1.52 g) were mixed. Subsequently, the mixture was applied to the measurement system of the rheometer and the curing characteristics were monitored at 90° C. over 120 min.

Example 8: Preparation of an Elastomer Precursor Using an Unsaturated Polyethercarbonate Polyol (Polyol-1) with 2.2% by Weight of Double Bonds and Polysiloxane-2 in a Molar Ratio of 1 Double Bonds (C═C):1 Silane (Si—H)

[0216] In a crimp-cap bottle, polysiloxane 2 (5.6 g) and platinum(0)-1,3-divinyl-1,1,3,3-tetramethyldisioxane (4.5 mg) were blended with one another (mixture 6).

[0217] In a weighing boat, polyol-1 (500 mg) and mixture 6 (240 mg) were mixed. Subsequently, the mixture was applied to the measurement system of the rheometer and the curing characteristics were monitored at 90° C. over 120 min.

TABLE-US-00003 TABLE 3 Molar G′ Polyether- ratio of Gel after Ex- carbonate (C═C) to point 2 h ample polyol Crosslinker (Si—H).sup.a) [s] [Pa] 7 Polyol-1 Polysiloxane- 1:1 <60 19900 1 8 Polyol-1 Polysiloxane- 1:1 <60 2950 2 4 Polyol-1 — No curing No curing 0 (comp.) Comp.: comparative example; .sup.a)molar ratio of the carbon-carbon double bonds (C═C) in the polyethercarbonate polyol to the Si—H bonds of the polysiloxane compound

[0218] Examples 7-8 show that the change in the ratio between double bond and silane (Si—H) leads to a different network density and reaction time. In the case of a stoichiometric silane content, the stability of the network formed increases assumes a maximum.

Example 9: Preparation of an Elastomer Precursor Using an Unsaturated Polyethercarbonate Polyol (Polyol-2) with 2.2% by Weight of Double Bonds and Polysiloxane-1 in a Molar Ratio of 1 Double Bonds (C═C):1 Silane

[0219] In a crimp-cap bottle, polysiloxane 1 (38 g) and platinum(0)-1,3-divinyl-1,1,3,3-tetramethyldisioxane (4.5 mg) were blended with one another (mixture 7).

[0220] In a weighing boat, polyol-2 (500 mg) and mixture 7 (1.52 g) were mixed. Subsequently, the mixture was applied to the measurement system of the rheometer and the curing characteristics were monitored at 140° C. over 120 min.

Example 10: Preparation of an Elastomer Precursor Using an Unsaturated Polyethercarbonate Polyol (Polyol-2) with 2.2% by Weight of Double Bonds and Polysiloxane-2 in a Molar Ratio of 1 Double Bonds (C═C):1 Silane

[0221] In a crimp-cap bottle, polysiloxane 2 (10.34 g) and platinum(0)-1,3-divinyl-1,1,3,3-tetramethyldisioxane (29.21 mg) were blended with one another (mixture 8).

[0222] In a weighing boat, polyol-2 (500 mg) and mixture 8 (103.4 mg) were mixed. Subsequently, the mixture was applied to the measurement system of the rheometer and the curing characteristics were monitored at 140° C. over 120 min.

Example 11 (Comp.): Preparation of an Elastomer Precursor Using an Unsaturated Polyethercarbonate Polyol (Polyol-2) with 2.2% by Weight of Double Bonds

[0223] Polyol-2 (500 mg) was supplemented with 300 ppm of catalyst and applied to the measurement system of the rheometer and the curing characteristics were monitored at 140° C. over 120 min.

[0224] Analysis by means of IR spectroscopy showed the characteristic signal for double bonds at 1645 cm.sup.−1.

TABLE-US-00004 TABLE 4 Ratio of G′ Polyether- (C═C) after Ex- carbonate to Gel point 2 h ample polyol Crosslinker Si—H [s] [Pa] 9 Polyol-2 Polysiloxane- 1:1 150 217 1 10 Polyol-2 Polysiloxane- 1:1 6167 25.6 2 11 Polyol-2 — No curing No curing 0 (comp.) Comp.: comparative example

[0225] Examples 8-9 show the influence of the silane (Si—H) content chosen on gel time and network density.