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

Abstract

The invention relates to a method for producing a polymer which contains organooxysilyl end groups. The method first has the step of reacting a polyoxyalkylene polyol which contains carbon-carbon multiple bonds with a organooxysilyl compound of the formula Si(X)n(R)4-n in the presence of a catslyst, wherein X independently of one another represents C1-C8-alkoxy, C7-C20-aralkoxy, C6-C14-aroxy, C7-C20-alkylaroxy, C1-C20-acyloxy; R independently of one another represents a saturated or unsaturated C1-C22-alkyl, C6-C14-aryl, C7-C14-aralkyl, C7-C14-alkylaryl; and n is 2, 3, or 4. The invention additionally relates to a method for producing an elastomer precursor from the polymer which contains organooxysilyl end groups and to products which can be obtained using said method.

Claims

1. A process for preparing a polymer containing organooxysilyl end groups, comprising: A) reacting a polyoxyalkylene polyol containing carbon-carbon multiple bonds with an organooxysilyl compound of the formula Si(X).sub.n(R.sub.0).sub.4-n in the presence of a catalyst, where: X is independently C1-C8-alkoxy, C7-C20-aralkoxy, C6-C14-aroxy, C7-C20-alkylaroxy, or C1-C20-acyloxy; R.sub.0 is independently saturated or unsaturated C1-C22-alkyl, C6-C14-aryl, C7-C14-aralkyl, or C7-C14-alkylaryl, and n is 3 or 4.

2. The process as claimed in claim 1, wherein the carbon-carbon multiple bond-containing polyoxyalkylene polyol is obtained by an adding alkylene oxide, a carbon-carbon multiple bond containing monomer and CO.sub.2 onto an H-functional starter substance in the presence of a double metal cyanide catalyst.

3. The process as claimed in claim 2, wherein the carbon-carbon multiple bond-containing monomer is present in an amount of 0.1% by weight to 60% by weight, based on the total molar amount of alkylene oxide, carbon dioxide and the carbon-carbon multiple bond-containing monomer used.

4. The process as claimed in claim 2, wherein the at least one carbon-carbon multiple bond-containing monomer comprises: (a) allyl glycidyl ether, vinylcyclohexene oxide, cyclooctadiene monoepoxide, cyclododecatriene monoepoxide, butadiene monoepoxide, isoprene monoepoxide, limonene oxide, 1,4-divinylbenzene monoepoxide, 1,3-divinylbenzene monoepoxide, a glycidyl ester of an unsaturated fatty acid, a partly epoxidized fat, a partly oxidized oil, or a mixture of any two or more thereof; (b) an alkylene oxide of the general formula (IX): ##STR00009## where R.sub.1 to R.sub.3 are independently H, a halogen, a substituted or unsubstituted C1-C22 alkyl, or a substituted or unsubstituted C6-C12 aryl; (c) a cyclic anhydride of the general formula (X), (XI) or (XII): ##STR00010## where R.sub.1 to R.sub.10 are independently H, a halogen, a substituted or unsubstituted C1-C22 alkyl, or substituted or unsubstituted C6-C12 aryl, (d) 4-cyclohexene-1,2-dioic anhydride, 4-methyl-4-cyclohexene-1,2-dioic anhydride, 5,6-norbornene-2,3-dioic anhydride, allyl-5,6-norbornene-2,3-dioic anhydride, dodecenylsuccinic anhydride, tetradecenylsuccinic anhydride, hexadecenylsuccinic anhydride, octadecenylsuccinic anhydride, or a mixture of any two or more thereof; or (e) an alkylene oxide of the general formula (XIII): ##STR00011## where R.sub.14 is a saturated or unsaturated C1-C22-alkyl, C6-C14-aryl, C7-C14-aralkyl, or C7-C14-alkylaryl.

5. The process as claimed in claim 4, wherein the at least one carbon-carbon multiple bond-containing monomer comprises: (a) allyl glycidyl ether, vinylcyclohexene oxide and limonene oxide, (b) glycidyl acrylate and glycidyl methacrylate, (c) maleic anhydride, itaconic anhydride, and cis-1,2,3,6-tetrahydrophthalic anhydride, (d) 4-cyclohexene-1,2-dioic anhydride and 5,6-norbornene-2,3-dioic anhydride, or (e) glycidyl propargyl ether.

6. The process as claimed in claim 1, wherein the polyoxyalkylene polyol containing carbon-carbon multiple bonds comprises a polyethercarbonate polyol containing carbon-carbon multiple bonds in which the polyethercarbonate polyol has a CO.sub.2 content of 3% by weight to 44% by weight.

7. The process as claimed in claim 1, wherein the organooxysilyl compound comprises trimethoxysilane, methyltrimethoxysilane, phenyltrimethoxysilane, triethoxysilane, methyltriethoxysilane, methyltripropoxysilane, hexadecyltrimethoxysilane, octodecyltrimethoxysilane, noctyltrimethoxysilane, n-octyltriethoxysilane, propyltrimethoxysilane, propyltriethoxysilane, N-butyltrimethoxysilane, n-butyltriethoxysilane, iso-butyltriethoxysilane, 3-chloropropyltrimethoxysilane, 3-chloropropyltriethoxysilane, 3-chloropropylmethyldiethoxysilane, chloromethyltrimethoxysilane, chloromethyltriethoxysilane, dichloromethyltriethoxysilane, tetramethoxysilane, tetraethoxysilane, tetraisopropoxysilane or a combination of any two or more thereof.

8. The process as claimed in claim 7, wherein the organooxysilyl compound comprises trimethoxysilane, triethoxysilane, tetramethoxysilane, tetraethoxysilane, tetraisopropoxysilane, or a combination of any two or more thereof.

9. The process as claimed in claim 1, wherein the catalyst present in step A) comprises: (a) an amine of the general formula (XIV): ##STR00012## where: R.sub.15 and R.sub.16 are independently hydrogen, alkyl or aryl; or R.sub.15 and R.sub.16 together with the nitrogen atom supporting-them form an aliphatic, unsaturated or aromatic heterocycle; n is an integer from 1 to 10; R.sub.17 is hydrogen, alkyl, aryl, or (CH2)xN(R18)(R19) where: R18 and R19 are independently hydrogen, alkyl or aryl; or R18 and R19 together with the nitrogen atom supporting them form an aliphatic, unsaturated or aromatic heterocycle; and x is an integer 5 from 1 to 10; (b) an amine of the general formula (XV): ##STR00013## where: R.sub.20 is hydrogen, alkyl or aryl; R.sub.21 and R.sub.22 are independently hydrogen, alkyl or aryl; m and o are independently an integer from 1 to 10; and/or: (c) diazabicyclo[2.2.2]octane, diazabicyclo[5.4.0]undec-7-ene, dialkylbenzylamine, dimethylpiperazine, 2,2-dimorpholinyl diethyl ether, 4-dimethylaminopyridine and/or pyridine.

10. The process as claimed in claim 9, wherein the catalyst present in step A) comprises diazabicyclo[2.2.2]octane, diazabicyclo[5.4.0]undec-7-ene 4-dimethylaminopyridine, or a combination of any two or more thereof.

11. A polymer containing organooxysilyl end groups, obtained by the process as claimed in claim 1, wherein the organoalkoxysilyl end groups have a number-average molecular weight Mn of 500 g/mol to 100000 g/mol, determined by means of gel permeation chromatography according to DIN 55672-1.

12. A process for preparing an elastomer precursor, comprising : B) heating the polymer containing organooxysilyl end groups as claimed in claim 11 to a temperature of 65 C. in the presence of a catalyst.

13. The process as claimed in claim 12, wherein the catalyst present in step B) comprises: (a) an amine of the general formula (XIV): ##STR00014## where: R.sub.15 and R.sub.16 are independently hydrogen, alkyl or aryl; or R.sub.15 and R.sub.16 together with the nitrogen atom supporting them form an aliphatic, unsaturated or aromatic heterocycle; n is an integer from 1 to 10; R.sub.17 is hydrogen, alkyl, aryl, or (CH2)xN(R18)(R19) where: R18 and R19 are independently hydrogen, alkyl or aryl; or R18 and R19 together with the nitrogen atom supporting them form an aliphatic, unsaturated or aromatic heterocycle; x is an integer from 1 to 10; (b) an amine of the general formula (XV): ##STR00015## where: R.sub.20 is hydrogen, alkyl or aryl; R.sub.21 and R.sub.22 are independently hydrogen, alkyl or aryl; m and o are independently an integer from 1 to 10; and/or (c) diazabicyclo[2.2.2]octane, diazabicyclo[5.4.0]undec-7-ene, dialkylbenzylamine, dimethylpiperazine, 2,2-dimorpholinyl diethyl ether, 4-dimethylaminopyridine, pyridine, or a combination of any two or more thereof.

14. The process as claimed in claim 13, wherein the catalyst present in step B) comprises diazabicyclo[2.2.2]octane, diazabicyclo[5.4.0]undec-7-ene 4-dimethylaminopyridine, or a combination of any two or more thereof.

15. An elastomer precursor obtained by the process as claimed in claim 12.

Description

EXAMPLES

[0249] The present invention is described further by the examples which follow, but without being limited thereto.

[0250] Polyols Used:

TABLE-US-00001 PET-1 poly(oxypropylene) polyol, difunctional, with an OH number of 112 mg.sub.KOH/g

[0251] Polyol A polyoxyalkylene polyol containing carbon-carbon double bonds, prepared by the method specified below

[0252] Alkylene Oxide:

TABLE-US-00002 PO propylene oxide (Chemogas NV, 99.9%)

[0253] Monomer Containing Carbon-Carbon Double Bonds:

TABLE-US-00003 MA maleic anhydride (Sigma-Aldrich, 99%)

[0254] Organooxysilyl Compounds Used:

TABLE-US-00004 MeSi(OEt).sub.3 methyltriethoxysilane, monofunctional organooxysilyl compound (Sigma-Aldrich, 99%) Me.sub.2Si(OEt).sub.2 dimethyldiethoxysilane, difunctional organooxysilyl compound (Sigma-Aldrich, 97%) Me.sub.3Si(OEt) trimethylethoxysilane, trifunctional organooxysilyl compound (Sigma-Aldrich, 98%) Si(OEt).sub.4 tetraethoxysilane, tetrafunctional organooxysilyl compound (Sigma-Aldrich, >99%) MeSi(OMe).sub.3 methyltrimethoxysilane, trifunctional organooxysilyl compound (Sigma-Aldrich, 98%) MeSi(OAc).sub.3 methyltriacetoxysilane, trifunctional organooxysilyl compound (Sigma-Aldrich, 90%)

[0255] Catalysts Used:

TABLE-US-00005 DMC catalyst prepared according to example 6 of WO-A01/80994 DBTL dibutyltin dilaurate (Sigma-Aldrich Chemie GmbH, 95%) BinDec bismuth neodecanoate (Sigma-Aldrich Chemie GmbH, not stated) DBU diazabicycloundecene (Acros Organics, 98%) FA formic acid (Honeywell Fluka, 98-100%)

[0256] Methods Used:

[0257] The increase in molecular weight of functionalized polyols through polycondensation was examined on a Physica MCR 501 rheometer from Anton Paar, equipped with a D-PP15 measuring system (plate/plate configuration with a plate spacing of 1 mm).

[0258] Each sample (0.5 g) of the functionalized polyol was mixed with catalyst on the rheometer plate of the rheometer and subjected to 10% shear at 80 C. and a dynamic oscillation of 1 Hz. Storage modulus (G) and loss modulus (G) were measured every 20 seconds over 120 minutes. The gel point chosen was the juncture at which storage modulus (G) and loss modulus (G) are of equal magnitude (G/G=1).

[0259] For .sup.1H NMR spectra, the sample was dissolved in deuterated chloroform and analyzed on a Bruker spectrometer (AV400, 400 MHz).

[0260] IR spectra were recorded on a Bruker spectrometer (Alpha P FT-IR).

[0261] Preparation of Polyol A (Polyoxyalkylene Polyol Containing Carbon-Carbon Double Bonds):

[0262] A polyoxyalkylene polyol containing carbon-carbon double bonds which is suitable in the method of the invention for the functionalization with organooxysilyl compound can be prepared by the following method:

[0263] Step :

[0264] A 970 ml pressure reactor equipped with a sparging stirrer was initially charged with a mixture of DMC catalyst (according to example 6 of WO 01/80994 A1; 161 mg) and PET-1 (125 g) and this initial charge was stirred (800 rpm) at 130 C. for 30 minutes under a partial vacuum (50 mbar), with passage of argon through the reaction mixture.

[0265] Step :

[0266] After injection of CO.sub.2 to 15 bar, in the course of which a slight drop in temperature was observed, and re-attainment of a temperature of 130 C., 3.0 g of propylene oxide was metered in with the aid of an HPLC pump (3 ml/min). The reaction mixture was stirred (800 rpm) at 130 C. for 20 min. The addition of 3.0 g of propylene oxide was repeated a second and third time.

[0267] Step :

[0268] The temperature was kept at 100 C. by closed-loop control and, during the subsequent steps, the pressure in the pressure reactor was kept at 15 bar with the aid of a mass flow regulator by metering in further CO.sub.2. While stirring, a further 355 g of a monomer mixture (14% by weight of maleic anhydride dissolved in propylene oxide) was metered in by means of an HPLC pump (3 ml/min), while continuing to stir the reaction mixture (800 rpm). After the addition of monomer mixture (14% by weight of maleic anhydride dissolved in propylene oxide) had ended, the reaction mixture was stirred at 100 C. for a further 60 min. The reaction was ended by cooling the pressure reactor in an ice bath, releasing the elevated pressure and analyzing the resulting product, adopting the methods described in WO 2015/032737 A1. The .sup.1H NMR spectrum of the polyol is shown in FIG. 1.

[0269] Molar ratio of carbonate groups to ether groups (e/f): 0.17

[0270] The proportion of carbonate units in the repeat units of the polyetherestercarbonate polyol (A.sub.carbonate in %): 12.9

[0271] The 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 in % by weight): 10.0

[0272] Molecular weight (M.sub.n in g/mol): 4421

[0273] Polydispersity: 1.2

Comparative Example 1: Preparation of a Polymer Containing Organooxysilyl End Groups by Reacting an Unsaturated Polyoxyalkylene Polyol with a Bifunctional Organooxysilyl Compound (F=1) and Increasing the Molecular Weight of the Product Obtained

[0274] Step A:

[0275] In a 100 ml two-neck flask, polyol A (10.0 g) and trimethylmonoethoxysilane (20.0 g) were combined. The flask was then fitted with a reflux condenser heated to 110 C. The mixture was brought to reaction temperature, 110 C., while stirring (300 rpm), and DBU (1% by weight, 100 mg) was added. The reaction mixture was then stirred at 110 C. for a further 2 h. On conclusion of the reaction, the unreacted dimethyldiethoxysilane was removed under reduced pressure. The product was analyzed by NMR spectroscopy and IR spectroscopy, and the functionalization of the polyol was confirmed.

[0276] Step B:

[0277] For the condensation experiment, 0.5 g of the functionalized unsaturated polyoxyalkylene polyol was mixed with DBU (2% by weight, 10 mg) and used in the rheometer. No gel point was observed.

Comparative Example 2: Preparation of a Polymer Containing Organooxysilyl End Groups by Reacting an Unsaturated Polyoxyalkylene Polyol with a Bifunctional Organooxysilyl Compound (F=2) and Increasing the Molecular Weight of the Product Obtained

[0278] Step A:

[0279] In a 100 ml two-neck flask, polyol A (10.0 g) and dimethyldiethoxysilane (20.0 g) were combined. The flask was then fitted with a reflux condenser heated to 110 C. The mixture was brought to reaction temperature, 110 C., while stirring (300 rpm), and DBU (1% by weight, 100 mg) was added. The reaction mixture was then stirred at 110 C. for a further 2 h. On conclusion of the reaction, the unreacted dimethyldiethoxysilane was removed under reduced pressure. The product was analyzed by NMR spectroscopy and IR spectroscopy, and the functionalization of the polyol was confirmed.

[0280] Step B:

[0281] For the condensation experiment, 0.5 g of the functionalized unsaturated polyoxyalkylene polyol was mixed with DBU (2% by weight, 10 mg) and used in the rheometer. No gel point was observed.

Example 3: Preparation of a Polymer Containing Organooxysilyl End Groups by Reacting an Unsaturated Polyoxyalkylene Polyol with a Trifunctional Organooxysilyl Compound (F=3) and Increasing the Molecular Weight of the Product Obtained

[0282] Step A:

[0283] In a 100 ml two-neck flask, polyol A (10.0 g) and methyltriethoxysilane (20.0 g) were combined. The flask was then fitted with a reflux condenser heated to 110 C. The mixture was brought to reaction temperature, 110 C., while stirring (300 rpm), and DBU (1% by weight, 100 mg) was added. The reaction mixture was then stirred at 110 C. for a further 2 h. On conclusion of the reaction, the unreacted methyltriethoxysilane was removed under reduced pressure. The product was analyzed by NMR spectroscopy and IR spectroscopy, and the functionalization of the polyol was confirmed.

[0284] Step B:

[0285] For the condensation experiment, 0.5 g of the functionalized unsaturated polyoxyalkylene polyol was mixed with 1% by weight of DBU and used in the rheometer. The gel point occurred after 89.3 min. The storage modulus G measured after 1 hour was 12.7 Pa.

Example 4: Preparation of a Polymer Containing Organooxysilyl End Groups by Reacting an Unsaturated Polyoxyalkylene Polyol with a Trifunctional Organooxysilyl Compound (F=3)

[0286] Step A:

[0287] In a 100 ml two-neck flask, polyol A (10.0 g) and methyltrimethoxysilane (20.0 g) were combined. The flask was then fitted with a reflux condenser heated to 110 C. The mixture was brought to reaction temperature, 110 C., while stirring (300 rpm), and DBU (1% by weight, 100 mg) was added. The reaction mixture was then stirred at 110 C. for a further 2 h. On conclusion of the reaction, the unreacted methyltrimethoxysilane was removed under reduced pressure. The product was analyzed by NMR spectroscopy and IR spectroscopy, and the functionalization of the polyol was confirmed.

Example 5: Preparation of a Polymer Containing Organooxysilyl End Groups by Reacting an Unsaturated Polyoxyalkylene Polyol with a Tetrafunctional Organooxysilyl Compound (F=4) and Increasing the Molecular Weight of the Product Obtained

[0288] Step A:

[0289] In a 100 ml two-neck flask, polyol A (10.0 g) and tetraethoxysilane (20.0 g) were combined. The flask was then fitted with a reflux condenser heated to 110 C. The mixture was brought to reaction temperature, 110 C., while stirring (300 rpm), and DBU (1% by weight, 100 mg) was added. The reaction mixture was then stirred at 110 C. for a further 2 h. On conclusion of the reaction, the unreacted tetraethoxysilane was removed under reduced pressure. The product was analyzed by NMR spectroscopy and IR spectroscopy, and the functionalization of the polyol was confirmed.

[0290] Step B:

[0291] For the condensation experiment, 0.5 g of the functionalized unsaturated polyoxyalkylene polyol was mixed with DBU (1% by weight, 5 mg) and used in the rheometer. The gel point was observed after 31.5 min. The storage modulus G was noted after one hour. The curing characteristics are shown in FIG. 2. The label G in FIG. 2 refers to the storage modulus, the label G to the loss modulus; t denotes the time in seconds.

Comparative Example 6: Condensation Experiment Using an Unsaturated Polyoxyalkylene Polyol

[0292] Step A:

[0293] In a flask, 9.0 g of polyol A and DBU (1% by weight, 90 mg) were mixed. The mixture was brought to reaction temperature (110 C.) while stirring (300 rpm). Then water (400 mg) was added to the reaction mixture. The reaction mixture was stirred for 2 h. On conclusion of the reaction, the volatile constituents were removed under reduced pressure.

[0294] Step B:

[0295] For the condensation experiment, 0.5 g of the unfunctionalized unsaturated polyoxyalkylene polyol was mixed with DBU (2% by weight, 10 mg) and used in the rheometer. No gel point was observed. This is in accordance with the assumption that the functionalized polyol does not have any reactive sites for formation of SiOSi groups.

Comparative example 7: Preparation of a Polymer Containing Organooxysilyl End Groups by Reacting an Unsaturated Polyoxyalkylene Polyol with a Trifunctional Organooxysilyl Compound (F=3) Using Formic Acid as Catalyst

[0296] The procedure was analogous to example 2, except that the catalyst used was 1% by weight of FA and the reaction temperature was 95 C. IR spectroscopy analysis of the product showed that the OH stretch vibration band around 3500 cm.sup.1 had not yet disappeared completely, and so incomplete reaction conversion under these conditions was concluded.

Comparative Example 8: Preparation of a Polymer Containing Organooxysilyl End Groups by Reacting an Unsaturated Polyoxyalkylene Polyol with a Trifunctional Organooxysilyl Compound (F=3)

[0297] In a 100 ml two-neck flask, polyol A (10.0 g) and methyltrimethoxysilane (20.0 g) were combined. The flask was then fitted with a reflux condenser heated to 110 C. The mixture was brought to reaction temperature, 110 C., while stirring (300 rpm), and DBTL (1% by weight, 100 mg) was added. The reaction mixture was then stirred at 110 C. for a further 2 h. On conclusion of the reaction, the unreacted methyltrimethoxysilane was removed under reduced pressure. The product was analyzed by .sup.1H NMR spectroscopy and IR spectroscopy, but it was not possible to confirm the functionalization of the polyol.

Comparative Example 9: Preparation of a Polymer Containing Organooxysilyl End Groups by Reacting an Unsaturated Polyoxyalkylene Polyol with a Trifunctional Organooxysilyl Compound (F=3)

[0298] In a 100 ml two-neck flask, polyol A (10.0 g) and methyltriethoxysilane (20.0 g) were combined. The flask was then fitted with a reflux condenser heated to 110 C. The mixture was brought to reaction temperature, 110 C., while stirring (300 rpm), and bismuth neodecanoate (1% by weight, 100 mg) was added. The reaction mixture was then stirred at 110 C. for a further 2 h. On conclusion of the reaction, the unreacted methyltriethoxysilane was removed under reduced pressure. The product was by .sup.1H NMR spectroscopy and IR spectroscopy, but it was not possible to confirm the functionalization of the polyol.

Comparative Example 10: Preparation of a Polymer Containing Organooxysilyl End Groups by Reacting an Unsaturated Polyoxyalkylene Polyol with a Trifunctional Organooxysilyl Compound (F=3) and Increasing the Molecular Weight of the Product Obtained

[0299] In a 100 ml two-neck flask, polyol A (10.0 g) and methyltriacetoxysilane (20.0 g) were combined. The flask was then fitted with a reflux condenser heated to 110 C. The mixture was brought to reaction temperature, 110 C., while stirring (300 rpm), and DBU (1% by weight, 100 mg) was added. The reaction mixture was then stirred at 110 C. for a further 2 h. On conclusion of the reaction, the unreacted methyltriacetoxysilane was removed under reduced pressure. The product was by .sup.1H NMR spectroscopy and IR spectroscopy, but it was not possible to confirm the functionalization of the polyol.

TABLE-US-00006 TABLE 1 Overview of the results from the preparation of the elastomer precursor Catalyst m(Cat(A)) m(Cat(B)) Gel point G (60 min) Example Si(X).sub.n(R).sub.4n n (A) = (B) [% by wt.] [% by wt.] [min] [Pa] 1 (comp.) Me.sub.3Si(OEt) 1 DBU 1 1 n.o. n.o. 2 (comp.) Me.sub.2Si(OEt).sub.2 2 DBU 1 1 n.o. n.o. 3 MeSi(OEt).sub.3 3 DBU 1 1 89.3 12.7 4 MeSi(OMe).sub.3 3 DBU 1 1 84.5 13.0 5 Si(OEt).sub.4 4 DBU 1 1 31.7 281 6 (comp.) DBU 0 1 n.o. n.o. 7 (comp.) MeSi(OEt).sub.3 3 FA 1 n.o. n.o. 8 (comp.) MeSi(OMe).sub.3 3 DBTL 1 n.o. n.o. 9 (comp.) MeSi(OMe).sub.3 3 BinDec 1 n.o. n.o. 10 (comp.) MeSi(OAc).sub.3 3 DBU 1 n.o. n.o. comp. = comparison; n.o. = not observed

[0300] Comparative examples 1 and 2 show that, in the case of functionalization with mono- or bifunctional organosilyl groups, no crosslinking of the corresponding products can be achieved. Examples 6-9 and 11 show that the presence of an amine-based catalyst is a prerequisite for the success of both step A and step B. By contrast, the compounds listed in comparative examples 7-10 showed no catalytic activity.

Example 12: Preparation of a Polymer Containing Organooxysilyl End Groups by Reacting an Unsaturated Polyoxyalkylene Polyol with a Tetrafunctional Organooxysilyl Compound (F=4) and Increasing the Molecular Weight of the Product Obtained

[0301] The functionalized and unsaturated polyoxyalkylene polyol prepared in example 5 was used for this condensation experiment.

[0302] For the condensation experiment, 0.5 g of the functionalized unsaturated polyoxyalkylene polyol was mixed with DBU (2% by weight, 10 mg) and used in the rheometer. The gel point was observed after 13.7 min. The storage modulus G was noted after one hour.

Example 13: Preparation of a Polymer Containing Organooxysilyl End Groups by Reacting an Unsaturated Polyoxyalkylene Polyol with a Tetrafunctional Organooxysilyl Compound (F=4) and Increasing the Molecular Weight of the Product Obtained

[0303] The functionalized and unsaturated polyoxyalkylene polyol prepared in example 5 was used for this condensation experiment.

[0304] For the condensation experiment, 0.5 g of the functionalized unsaturated polyoxyalkylene polyol was mixed with DBU (4% by weight, 20 mg) and used in the rheometer. The gel point was observed after 7.0 min. The storage modulus G was noted after one hour.

Example 14: Preparation of a Polymer Containing Organooxysilyl End Groups by Reacting an Unsaturated Polyoxyalkylene Polyol with a Tetrafunctional Organooxysilyl Compound (F=4) and Increasing the Molecular Weight of the Product Obtained

[0305] The functionalized and unsaturated polyoxyalkylene polyol prepared in example 5 was used for this condensation experiment.

[0306] For the condensation experiment, 0.5 g of the functionalized unsaturated polyoxyalkylene polyol was mixed with DBU (8% by weight, 40 mg) and used in the rheometer. The gel point was observed after 4.5 min. The storage modulus G was noted after one hour.

TABLE-US-00007 TABLE 2 Overview of the results from the preparation of the elastomer precursor at different catalyst concentration of DBU in step B Catalyst m(Cat(A)) m(Cat(B)) Gel point G (60 min) Example Si(X).sub.n(R).sub.4n n (A) = (B) [% by wt.] [% by wt.] [min] [Pa] 11 (comp.) Si(OEt).sub.4 4 DBU 1 0 n.o. n.o. 5 Si(OEt).sub.4 4 DBU 1 1 31.7 281 12 Si(OEt).sub.4 4 DBU 1 2 13.7 1695 13 Si(OEt).sub.4 4 DBU 1 4 7.0 2825 14 Si(OEt).sub.4 4 DBU 1 8 4.5 7405

[0307] Examples 5, 12-14 and comparative example 11 show not only that the presence of amine-based catalysts is essential, but also that the concentration of those same catalysts has an influence on the progression of the reaction and the properties of the resulting product.