METHOD FOR PRODUCING TEMPERATURE-STABLE POLYALKENYLENES

Abstract

The present invention relates to a process for producing cycloalkenamer-containing compositions. The polymerization of cycloalkenamer is stopped by addition of alkyl vinyl ethers. This is followed by a membrane filtration. This type of production affords polyalkenamers that are thermally stable at 180 C.

Claims

1-14. (canceled)

15. A process for producing a polyalkenamer-containing composition, comprising the steps of: a) reacting at least one cycloalkene by ring-opening metathesis polymerization in at least one organic solvent to obtain a polyalkenamer-containing product mixture, wherein the polymerization is performed in the presence of at least one metal-containing catalyst and wherein the metal is selected from rhenium, ruthenium, osmium or mixtures thereof, wherein the cycloalkene is selected from the group consisting of cyclobutene, cyclopentene, cycloheptene, cyclooctene, cyclononene, cyclodecene, cyclododecene, cycloocta-1,5-diene, 1,5-dimethylcycloocta-1,5-diene, cyclodecadiene, norbornadiene, cyclododeca-1,5,9-triene, trimethylcyclododeca-1,5,9-triene, norbornene (bicyclo[2.2.1]hept-2-ene), 5-(3-cyclohexenyl)-2-norbornene, 5-ethyl-2-norbornene, 5-vinyl-2-norbomene, 5-ethylidene-2-norbornene, dicyclopentadiene and mixtures thereof, b) adding at least one alkyl vinyl derivative selected from alkyl vinyl ether, alkyl vinyl sulfide or mixtures thereof after the polymerization and c) working up the product mixture to remove the catalyst to obtain the polyalkenamer-containing composition, wherein the workup is carried out by membrane filtration in at least one organic solvent.

16. The process of claim 15, wherein the alkyl vinyl derivative is selected from the group consisting of: methyl vinyl ether, ethyl vinyl ether, propyl vinyl ether, butyl vinyl ether and mixtures thereof.

17. The process of claim 16, wherein methyl vinyl sulfide, ethyl vinyl sulfide, propyl vinyl sulfide, butyl vinyl sulfide and mixtures thereof are added as the alkyl vinyl sulfide.

18. The process of claim 15, wherein the membrane of the membrane filtration has a separation-active layer selected from polymers, glass, metal, ceramic or mixtures thereof.

19. The process of claim 18, wherein the separation-active layer of the membrane is selected from the group consisting of: crosslinked silicone acrylates, polydimethylsiloxane (PDMS) and polyimide.

20. The process of claim 15, wherein the membrane filtration is an ultrafiltration.

21. The process of claim 15, wherein the cycloalkene is selected from the group consisting of cyclopentene, cycloheptene, cyclooctene, cyclododecene and mixtures thereof.

22. The process of claim 21, wherein the cycloalkene comprises cyclooctene.

23. The process of claim 15, wherein the polymerization is performed in a nonpolar aromatic or aliphatic solvent.

24. The process of claim 15, wherein the same solvent is used for the polymerization and the membrane filtration.

25. The process of claim 15, wherein the metal of the catalyst comprises ruthenium.

26. The process of claim 15, wherein the reaction of cycloalkenes is carried out in the presence of a chain transfer agent.

27. The process of claim 15, wherein the chain transfer agent is a acyclic alkene having one or more non-conjugated double bonds, or a cyclic compound having a double bond in their side chain.

28. The process of claim 21, wherein the polymerization is performed in a nonpolar aromatic or aliphatic solvent.

29. The process of claim 21, wherein the metal of the catalyst comprises ruthenium.

30. The process of claim 22, wherein the reaction of cycloalkenes is carried out in the presence of a chain transfer agent.

31. The process of claim 30, wherein the chain transfer agent is a acyclic alkene having one or more non-conjugated double bonds, or a cyclic compound having a double bond in its side chain.

32. The process of claim 30, wherein the membrane filtration is an ultrafiltration.

33. The process of claim 29, wherein the alkyl vinyl derivative is selected from the group consisting of: methyl vinyl ether, ethyl vinyl ether, propyl vinyl ether, butyl vinyl ether and mixtures thereof.

34. The process of claim 33, wherein methyl vinyl sulfide, ethyl vinyl sulfide, propyl vinyl sulfide, butyl vinyl sulfide and mixtures thereof are added as the alkyl vinyl sulfide.

Description

EXAMPLES

[0044] Methods of Determination

[0045] Weight-Average Molecular Weight

[0046] Determination of molecular weight was carried out by gel permeation chromatography (GPC) as per DIN 55672-1:2016-03. Measurements were performed with a GPC system from Knauer Wissenschaftliche Gerte GmbH. The polymer was measured as a solution in tetrahydrofuran (c=5 g/L, injection volume 100 L) on an SDV column (30 cm, 5 m, linear) with pre-column (SDV 5 cm, 5 m, 100 ) at 23 C. and a flow rate of 1 mL/min. Calculation of the average molar masses was carried out by means of the strip method against polystyrene standards. WinGPC UniChrom (Build 5350) software from PSS Polymer Standards Service GmbH was employed for evaluation.

[0047] Melting Point and Melting Enthalpy.

[0048] Determination of melting point and melting enthalpy was carried out by differential scanning calorimetry (DSC). Polymer samples between 5 and 10 mg were measured. Measurements were performed on a PerkinElmer DSC-7 instrument with 20 mL/min of nitrogen 5.0 as purging gas. The measurement program contained a first heating from 90 C. to 80 C. (heating rate 20 K/min), a cooling from 80 C. to 90 C. (cooling rate 20K/min) and a second heating from 90 C. to 80 C. (heating rate 20 K/min). The melting point and the melting enthalpy of the polyalkenamers was determined using the second heating.

[0049] Trace Elemental Analysis

[0050] Determination of trace elements from the catalyst in the polyalkenamer were performed quantitatively by ICP-MS. 0.1-0.2 g of sample were digested in 10 ml of 65% by weight HNO.sub.3 and 2 mL of water at not more than 130 bar of pressure and not more than 300 C. The digestate was evaporated in a closed system at not more than about 95 C., dissolved with 0.5 mL of HNO.sub.3 and made up to 20 mL with water. The content of various elements in the solution was determined quantitatively with a Thermo Fisher ICAP Q quadrupole ICPMS.

Example 1A: Synthesis of Polyoctenamer in Heptane with Tungsten/Aluminium Catalyst System

[0051] 585 mL of heptane, 100 g of cyclooctene (COE) and 0.34 g of vinyl cyclohexene (VCH) were charged into a dry 2 L glass reactor under argon. The reaction mixture was heated to 30 C. and 0.4 mL of a solution of ethylaluminium dichloride (20% by weight) in heptane was added. Subsequently, 1 mL of a solution of tungsten hexachloride/propylene oxide ( mol/mol) in toluene (2.8% by weight of tungsten) were added slowly. A temperature increase of 5 C. was observed and the reaction mixture became markedly more viscous. The contents of the reactor were then discharged and a solution of 20% by weight of polyoctenamer in heptane was obtained.

Example 1B (Comparative Example): Membrane Purification of Polyoctenamer in Heptane with Tungsten/Aluminium Catalyst System

[0052] 1.25 L of the solution of 20% by weight of polyoctenamer in heptane (produced as per example 1A) was further diluted to 5% by weight with 3.75 L of heptane. The obtained 5 L of polymer solution was purified by diafiltration through a PuraMem UF (cut-off about 35 000 Da) ultrafiltration polymer membrane from Evonik Resource Efficiency GmbH. This was carried out using a crossflow filtration system with an 1812 membrane module (membrane area about 0.14 m.sup.2). In a diafiltration the membrane is used as a semipermeable barrier, the large molecules (polymer) being retained and the small molecules (impurities) being washed out through the membrane by solvent addition. The addition of fresh solvent was synchronized with the permeate flow so that the fill level in the feed container remained constant. The experiment was performed at 50 C. and 3 bar and altogether 25 L of fresh heptane were added (5 washing volumes in relation to the starting volume of the polymer solution). 5 L of polymer solution were obtained as retentate after this purification. 25 L of permeate solution were also obtained.

[0053] Heat Treatment at 180 C.

[0054] For analytical purposes 10 mL of the retentate (purified polymer solution) were dried in an aluminium dish in a vacuum drying cabinet over 20 h at 180 C. and a vacuum of 1 mbar after inertization with nitrogen. 1.5 g of white solid were obtained. The NMR spectrum of the solid corresponded to the expected structure of a polyoctenamer which contained 0.25 mol % of vinyl end groups and 0.30 mol % of cyclohexene end groups.

[0055] .sup.1H NMR (CDCl.sub.3, 500 MHz, 30 C.) (ppm): polyoctenamer: 5.38, 5.34, 2.01, 1.96, 1.30; end groups: 5.81 (m, 1H, CH2CHCH2-), 5.66 (d, 2H, CH2-CHCHCH2), 5.38-5.34 (m, 2H, CHCHCHCH2), 4.95 (m, 2H, CH2CHCH2-).

Melting point: 54 C.
Melting enthalpy: 75 J/g
Molar mass M.sub.w: 135 000 g/mol
Oligomer proportion (M<3000 g/mol): 3.8%

[0056] A trace elemental analysis showed that the polymer contained 250 ppm of tungsten, 125 ppm of aluminium and 110 ppm of chlorine.

Example 2A: Synthesis of Polyolyoctenamer in Heptane with Ru Catalyst

[0057] 1 L of heptane, 300 g of cyclooctene (COE) and 1.03 g of vinyl cyclohexene (VCH) were charged into a dry 2 L glass reactor under argon. The reaction mixture was heated to 70 C. and a solution of 14.4 mg of tricyclohexylphosphine[1,3-bis(2,4,6-trimethylphenyl)-4,5-dimethylimidazol-2-ylidene](2-thienylmethyliden)ruthenium(II) dichloride (catalyst C3) in 3.27 mL of toluene was added. A temperature increase of 16 C. was observed and the reaction mixture became markedly more viscous. The contents of the reactor were then discharged and a solution of 30% by weight of polyoctenamer in heptane was obtained.

Example 2B (Comparative Example): Membrane Purification of Polyoctenamer in Heptane with Ru Catalyst

[0058] 1.25 L of the solution of 20% by weight of polyoctenamer in heptane (produced as per example 2A) was further diluted to 5% by weight with 3.75 L of heptane. The obtained 5 L of polymer solution was purified by diafiltration through a PuraMem UF (cut-off about 35 000 Da) ultrafiltration polymer membrane from Evonik Resource Efficiency GmbH. This was carried out using a crossflow filtration system with an 1812 membrane module (membrane area about 0.14 m.sup.2). The addition of fresh solvent was synchronized with the permeate flow so that the fill level in the feed container remained constant. The experiment was performed at 50 C. and 3 bar and altogether 25 L of fresh heptane were added (5 washing volumes in relation to the starting volume of the polymer solution). 5 L of polymer solution were obtained as retentate after this purification. 25 L of permeate solution were also obtained.

[0059] Heat Treatment at 80 C.

[0060] For analytical purposes 10 mL of this solution were dried in an aluminium dish in a vacuum drying cabinet over 3 h at 80 C. and a vacuum of 1 mbar after inertization with nitrogen. 2 g of white solid were obtained. The NMR spectrum of the solid partly corresponded to the expected structure of a polyoctenamer (see above) but the end groups (vinyl and cyclohexene end groups) were absent and unknown signals were observed in the olefin region.

[0061] Heat Treatment at 180 C.

[0062] For analytical purposes 10 mL of this solution were dried in an aluminium dish in a vacuum drying cabinet over 20 h at 180 C. and a vacuum of 1 mbar after inertization with nitrogen. 2 g of white solid were obtained. The NMR spectrum of the solid partly corresponded to the expected structure of a polyoctenamer (see above) but the end groups (vinyl and cyclohexene end groups) were absent and unknown signals were observed in the olefin region.

Melting point: 30 C.
Melting enthalpy: 58 J/g

[0063] The markedly lower melting point and melting enthalpy values compared to drying at 80 C. showed that the polymer was unstable at a temperature of 180 C. The polymer solution contained fine grey particles that blocked the membrane so that further use thereof was not possible. The grey particles were presumably inorganic ruthenium-containing compounds which were insoluble and remained in the polymer after drying.

Example 3A (Comparative Example): Synthesis of Polyoctenamer in Heptane with Ru Catalyst and Addition of Butyl Vinyl Ether

[0064] 1 L of heptane, 300 g of cyclooctene (COE) and 1.03 g of vinyl cyclohexene (VCH) were charged into a dry 2 L glass reactor under argon. The reaction mixture was heated to 70 C. and a solution of 14.4 mg of tricyclohexylphosphine[1,3-bis(2,4,6-trimethylphenyl)-4,5-dimethylimidazol-2-ylidene](2-thienylmethyliden)ruthenium(11) dichloride (catalyst C3) in 3.27 mL of toluene was added. A temperature increase of 17 C. was observed and the reaction mixture became markedly more viscous. After 30 min the temperature had returned to 70 C. and 2.73 g of butyl vinyl ether were added. After 2 h at 70 C. the contents of the reactor were discharged and a solution of 30% by weight of polyoctenamer in heptane was obtained.

[0065] Heat Treatment at 80 C.

[0066] For analytical purposes 10 mL of this solution were dried in an aluminium dish in a vacuum drying cabinet over 3 h at 80 C. and a vacuum of 1 mbar after inertization with nitrogen. 2 g of white solid were obtained. The NMR spectrum of the solid corresponded to the expected structure of a polyoctenamer which contained 0.31 mol % of vinyl end groups and 0.33 mol % of cyclohexene end groups.

[0067] .sup.1H NMR (CDCl.sub.3, 500 MHz, 30 C.) (ppm): polyoctenamer: 5.38, 5.34, 2.01, 1.96, 1.30; end groups: 5.81 (m, 1H, CH2CHCH2-), 5.66 (d, 2H, CH2-CHCHCH2), 5.38-5.34 (m, 2H, CHCHCHCH2), 4.95 (m, 2H, CH2CHCH2-).

Melting point: 57 C.
Melting enthalpy: 78 J/g
Molar mass M.sub.w: 104 000 g/mol
Oligomer proportion (M<3000 g/mol): 6%

[0068] Heat Treatment at 180 C.

[0069] For analytical purposes 10 mL of this solution were dried in an aluminium dish in a vacuum drying cabinet over 20 h at 180 C. and a vacuum of 1 mbar after inertization with nitrogen. 2 g of white solid were obtained. The NMR spectrum of the solid partly corresponded to the expected structure of a polyoctenamer (see above) but the end groups (vinyl and cyclohexene end groups) were absent and unknown signals were observed in the olefin region.

Melting point: 42 C.
Melting enthalpy: 64 J/g

[0070] The markedly lower melting point and melting enthalpy compared to drying at 80 C. showed that the polymer was unstable at a temperature of 180 C. A trace elemental analysis showed that the polymer contained 3 ppm of ruthenium.

Example 3B (Inventive): Membrane Purification of Polyoctenamer in Heptane with Ru Catalyst and Addition of Butyl Vinyl Ether

[0071] 1.25 L of the solution of 20% by weight of polyoctenamer in heptane (produced as per example 3A) was further diluted to 5% by weight with 3.75 L of heptane. The obtained 5 L of polymer solution was purified by diafiltration through a PuraMem UF (cut-off about 35 000 Da) ultrafiltration polymer membrane from Evonik Resource Efficiency GmbH. This was carried out using a crossflow filtration system with an 1812 membrane module (membrane area about 0.14 m.sup.2). The addition of fresh solvent was synchronized with the permeate flow so that the fill level in the feed container remained constant. The experiment was performed at 50 C. and 3 bar and altogether 25 L of fresh heptane were added (5 washing volumes in relation to the starting volume of the polymer solution). 5 L of polymer solution were obtained as retentate after this purification. 25 L of permeate solution were also obtained.

[0072] Heat Treatment at 180 C.

[0073] For analytical purposes 10 mL of the retentate (purified polymer solution) were dried in an aluminium dish in a vacuum drying cabinet over 20 h at 180 C. and a vacuum of 1 mbar after inertization with nitrogen. 2 g of white solid were obtained. The NMR spectrum of the solid corresponded to the expected structure of a polyoctenamer which contained 0.29 mol % of vinyl end groups and 0.30 mol % of cyclohexene end groups.

[0074] .sup.1H NMR (CDCl.sub.3, 500 MHz, 30 C.) (ppm): polyoctenamer: 5.38, 5.34, 2.01, 1.96, 1.30; end groups: 5.81 (m, 1H, CH2CHCH2-), 5.66 (d, 2H, CH2-CHCHCH2), 5.38-5.34 (m, 2H, CHCHCHCH2), 4.95 (m, 2H, CH2CHCH2-).

Melting point: 57 C.
Melting enthalpy: 78 J/g
Molar mass M.sub.w: 113 000 g/mol
Oligomer proportion (M<3000 g/mol): 3.2%

[0075] The high melting point (>56 C.) and the high melting enthalpy (>75 J/g) showed that the purified polyoctenomer was stable under the temperature conditions at 180 C.

[0076] The reduction in the oligomer proportion in the GPC compared to the starting solution (see example 3A) showed that this purification by ultrafiltration allowed separation of oligomers. A trace elemental analysis showed that the polymer contained only 1.5 ppm of ruthenium. In addition, no insoluble particles in the polymer solution were observed.

Example 4A (Comparative Example): Synthesis of Polyoctenamer in Heptane with Ru Catalyst and Addition of Ethyl Vinyl Sulfide

[0077] 1 L of heptane, 300 g of cyclooctene (COE) and 1.03 g of vinyl cyclohexene (VCH) were charged into a dry 2 L glass reactor under argon. The reaction mixture was heated to 60 C. and a solution of 14.4 mg of tricyclohexylphosphine[1,3-bis(2,4,6-trimethylphenyl)-4,5-dimethylimidazol-2-ylidene](2-thienylmethyliden)ruthenium(11) dichloride (catalyst C3) in 3.27 mL of toluene was added. A temperature increase of 20 C. was observed and the reaction mixture became markedly more viscous. After 30 min the temperature had returned to 65 C. and 2.41 g of ethyl vinyl sulfide were added. After 2 h at 60 C. the contents of the reactor were discharged and a solution of 30% by weight of polyoctenamer in heptane was obtained.

[0078] Heat Treatment at 80 C.

[0079] For analytical purposes 10 mL of this solution were dried in an aluminium dish in a vacuum drying cabinet over 3 h at 80 C. and a vacuum of 1 mbar after inertization with nitrogen. 2 g of white solid were obtained. The NMR spectrum of the solid corresponded to the expected structure of a polyoctenamer which contained 0.31 mol % of vinyl end groups and 0.33 mol % of cyclohexene end groups.

[0080] .sup.1H NMR (CDCl.sub.3, 500 MHz, 30 C.) (ppm): polyoctenamer: 5.38, 5.34, 2.01, 1.96, 1.30; end groups: 5.81 (m, 1H, CH2CHCH2-), 5.66 (d, 2H, CH2-CHCHCH2), 5.38-5.34 (m, 2H, CHCHCHCH2), 4.95 (m, 2H, CH2CHCH2-).

Melting point: 57 C.
Melting enthalpy: 79 J/g
Molar mass M.sub.w: 110 000 g/mol
Oligomer proportion (M<3000 g/mol): 3%

[0081] Heat Treatment at 180 C.

[0082] For analytical purposes 10 mL of this solution were dried in an aluminium dish in a vacuum drying cabinet over 20 h at 180 C. and a vacuum of 1 mbar after inertization with nitrogen. 2 g of white solid were obtained. The NMR spectrum of the solid partly corresponded to the expected structure of a polyoctenamer (see above) but the end groups (vinyl and cyclohexene end groups) were absent and unknown signals were observed in the olefin region.

Melting point: 40 C.
Melting enthalpy: 62 J/g

[0083] The markedly lower melting point and melting enthalpy compared to drying at 80 C. showed that the polymer was unstable at a temperature of 180 C. A trace elemental analysis showed that the polymer contained 5 ppm of ruthenium.

Example 4B (Inventive): Membrane Purification of Polyoctenamer in Heptane with Ru Catalyst and Addition of Ethyl Vinyl Sulfide

[0084] 1.25 L of the solution of 20% by weight of polyoctenamer in heptane (produced as per example 3A) was further diluted to 5% by weight with 3.75 L of heptane. The obtained 5 L of polymer solution was purified by diafiltration through a PuraMem UF (cut-off about 35 000 Da) ultrafiltration polymer membrane from Evonik Resource Efficiency GmbH. This was carried out using a crossflow filtration system with an 1812 membrane module (membrane area about 0.14 m.sup.2). The addition of fresh solvent was synchronized with the permeate flow so that the fill level in the feed container remained constant. The experiment was performed at 50 C. and 3 bar and altogether 25 L of fresh heptane were added (5 washing volumes in relation to the starting volume of the polymer solution). 5 L of polymer solution were obtained as retentate after this purification. 25 L of permeate solution were also obtained.

[0085] Heat Treatment at 180 C.

[0086] For analytical purposes 10 mL of the retentate (purified polymer solution) were dried in an aluminium dish in a vacuum drying cabinet over 20 h at 180 C. and a vacuum of 1 mbar after inertization with nitrogen. 2 g of white solid were obtained. The NMR spectrum of the solid corresponded to the expected structure of a polyoctenamer which contained 0.29 mol % of vinyl end groups and 0.30 mol % of cyclohexene end groups.

[0087] .sup.1H NMR (CDCl.sub.3, 500 MHz, 30 C.) (ppm): polyoctenamer: 5.38, 5.34, 2.01, 1.96, 1.30; end groups: 5.81 (m, 1H, CH2CHCH2-), 5.66 (d, 2H, CH2-CHCHCH2), 5.38-5.34 (m, 2H, CHCHCHCH2), 4.95 (m, 2H, CH2CHCH2-).

Melting point: 57 C.
Melting enthalpy: 80 J/g
Molar mass M.sub.w: 125 000 g/mol
Oligomer proportion (M<3000 g/mol): 0.7%

[0088] The high melting point (>56 C.) and the high melting enthalpy (>75 J/g) showed that the purified polyoctenomer was stable under the temperature conditions at 180 C.

[0089] The reduction in the oligomer proportion in the GPC compared to the starting solution (see example 4A) showed that this purification by ultrafiltration allowed separation of oligomers. A trace elemental analysis showed that the polymer contained only 2.4 ppm of ruthenium. In addition, no insoluble particles in the polymer solution were observed.

Example 5A: Synthesis of Polyoctenamer in Toluene with Ru Catalyst and Addition of Butyl Vinyl Ether

[0090] 380 mL of toluene, 80 g of cyclooctene (COE) and 0.275 g of vinyl cyclohexene (VCH) were charged into a dry 2 L glass reactor under argon. The reaction mixture was heated to 70 C. A solution of 6.4 mg of tricyclohexylphosphine[1,3-bis(2,4,6-trimethylphenyl)-4,5-dimethylimidazol-2-ylidene](2-thienylmethyliden)ruthenium(11) dichloride (catalyst C3) in 1.45 mL of toluene was then added. The reaction temperature increased to 74 C. after 5 min and then fell to 70 C. again. The reaction mixture became markedly more viscous. 30 Min after the catalyst addition 0.73 g of butyl vinyl ether were added and the mixture was stirred at 70 C. over 2 h. The contents of the reactor were then discharged and a solution of 20% by weight of polyoctenamer in toluene was obtained.

[0091] Heat Treatment at 80 C.

[0092] For analytical purposes 10 mL of this solution were dried in an aluminium dish in a vacuum drying cabinet over 3 h at 80 C. and a vacuum of 1 mbar after inertization with nitrogen. 1.7 g of white solid were obtained. The NMR spectrum of the solid corresponded to the expected structure of a polyoctenamer which contained 0.3 mol % of vinyl end groups and 0.32 mol % of cyclohexene end groups.

[0093] .sup.1H NMR (CDCl.sub.3, 500 MHz, 30 C.) (ppm): polyoctenamer: 5.38, 5.34, 2.01, 1.96, 1.30; end groups: 5.81 (m, 1H, CH2CHCH2-), 5.66 (d, 2H, CH2-CHCHCH2), 5.38-5.34 (m, 2H, CHCHCHCH2), 4.95 (m, 2H, CH2CHCH2-).

Melting point: 56 C.
Melting enthalpy: 78 J/g
Molar mass M.sub.w: 101 000 g/mol
Oligomer proportion (M<3000 g/mol): 8%

[0094] Heat Treatment at 180 C.

[0095] For analytical purposes 10 mL of this solution were dried in an aluminium dish in a vacuum drying cabinet over 20 h at 180 C. and a vacuum of 1 mbar after inertization with nitrogen. 1.7 g of white solid were obtained. The NMR spectrum of the solid partly corresponded to the expected structure of a polyoctenamer (see above) but the end groups (vinyl and cyclohexene end groups) were absent and unknown signals were observed in the olefin region.

Melting point: 28 C.
Melting enthalpy: 66 J/g

[0096] The markedly lower melting point (<30 C.) and melting enthalpy (<70 J/g) values compared to drying at 80 C. showed that the polymer was unstable at a temperature of 180 C. A trace elemental analysis showed that the polymer contained 5 ppm of ruthenium.

Example 5B (Inventive): Membrane Purification of Polyoctenamer in Toluene with Ru Catalyst and Addition of Butyl Vinyl Ether

[0097] 125 mL of the solution of 20% by weight of polyoctenamer in toluene from example 4A was dilute with 375 mL of toluene. The obtained 500 mL of polymer solution (5% by weight in toluene) was filtered through a PuraMem UF (cut-off about 35 000 Da) ultrafiltration polymer membrane from Evonik Resource Efficiency GmbH. A crossflow filtration plant with 4 test cells and a total membrane area of 136 cm.sup.2 was used. The experiment was performed at 50 C. and 3 bar and altogether 3.5 L of fresh toluene were added (7 washing volumes in relation to the starting volume of the polymer solution). 500 mL of polymer solution were obtained as retentate after this purification. 3.5 L of permeate solution were also obtained.

[0098] Heat Treatment at 180 C.

[0099] For analytical purposes 10 mL of this retentate solution were dried in an aluminium dish in a vacuum drying cabinet over 20 h at 180 C. and a vacuum of 1 mbar after inertization with nitrogen. 1.7 g of white solid were obtained. The NMR spectrum of the solid corresponded to the expected structure of a polyoctenamer which contained 0.3 mol % of vinyl end groups and 0.32 mol % of cyclohexene end groups.

[0100] .sup.1H NMR (CDCl.sub.3, 500 MHz, 30 C.) (ppm): polyoctenamer: 5.38, 5.34, 2.01, 1.96, 1.30; end groups: 5.81 (m, 1H, CH2CHCH2-), 5.66 (d, 2H, CH2-CHCHCH2), 5.38-5.34 (m, 2H, CHCHCHCH2), 4.95 (m, 2H, CH2CHCH2-).

Melting point: 59 C.
Melting enthalpy: 78 J/g
Molar mass M.sub.w: 119 000 g/mol
Oligomer proportion (M<3000 g/mol): 1.4%

[0101] The high melting point (>56 C.) and the high melting enthalpy (>75 J/g) showed that the purified polyoctenomer was stable under the temperature conditions at 180 C. The reduction in the oligomer proportion in the GPC compared to the starting solution (see example 4A) showed that this purification by ultrafiltration allowed separation of oligomers. A trace element analysis showed that the polymer contained less than 1 ppm of ruthenium (amount below detection limit).

Example 6A: Synthesis of Polyoctenamer in Heptane with Tungsten/Aluminium Catalyst System and Addition of Butyl Vinyl Ether

[0102] 585 mL of heptane, 100 g of cyclooctene (COE) and 0.34 g of vinyl cyclohexene (VCH) were charged into a dry 2 L glass reactor under argon. The reaction mixture was heated to 30 C. and 0.4 mL of a solution of ethylaluminium dichloride (20% by weight) in heptane was added. Subsequently, 1 mL of a solution of tungsten hexachloride/propylene oxide ( mol/mol) in toluene (2.8% by weight of tungsten) were added slowly. A temperature increase of 5 C. was observed and the reaction mixture became markedly more viscous. The contents of the reactor were then discharged and a solution of 20% by weight of polyoctenamer in heptane was obtained.

Example 6B (Comparative Example): Membrane Purification of Polyoctenamer in Heptane with Tungsten/Aluminium Catalyst System and Addition of Butyl Vinyl Ether

[0103] 1.25 L of the solution of 20% by weight of polyoctenamer in heptane (produced as per example 5A) was further diluted to 5% by weight with 3.75 L of heptane. The obtained 5 L of polymer solution was purified by diafiltration through a PuraMem UF (cut-off about 35 000 Da) ultrafiltration polymer membrane from Evonik Resource Efficiency GmbH. This was carried out using a crossflow filtration system with an 1812 membrane module (membrane area about 0.14 m.sup.2). The addition of fresh solvent was synchronized with the permeate flow so that the fill level in the feed container remained constant. The experiment was performed at 50 C. and 3 bar and altogether 25 L of fresh heptane were added (5 washing volumes in relation to the starting volume of the polymer solution). 5 L of polymer solution were obtained as retentate after this purification. 25 L of permeate solution were also obtained.

[0104] Heat Treatment at 180 C.

[0105] For analytical purposes 10 mL of the retentate (purified polymer solution) were dried in an aluminium dish in a vacuum drying cabinet over 20 h at 180 C. and a vacuum of 1 mbar after inertization with nitrogen. 1.5 g of white solid were obtained. The NMR spectrum of the solid corresponded to the expected structure of a polyoctenamer which contained 0.25 mol % of vinyl end groups and 0.30 mol % of cyclohexene end groups.

[0106] .sup.1H NMR (CDCl.sub.3, 500 MHz, 30 C.) (ppm): polyoctenamer: 5.38, 5.34, 2.01, 1.96, 1.30; end groups: 5.81 (m, 1H, CH2CHCH2-), 5.66 (d, 2H, CH2-CHCHCH2), 5.38-5.34 (m, 2H, CHCHCHCH2), 4.95 (m, 2H, CH2CHCH2-).

Melting point: 54 C.
Melting enthalpy: 75 J/g
Molar mass M.sub.w: 135 000 g/mol
Oligomer proportion (M<3000 g/mol): 3.8%

[0107] A trace elemental analysis showed that the polymer contained 250 ppm of tungsten, 125 ppm of aluminium and 110 ppm of chlorine.

SUMMARY

[0108]

TABLE-US-00001 Addition of alkyl vinyl Results after derivative Membrane 180 C. heat Example Catalyst Solvent after reaction filtration treatment 1A EADC/WCl.sub.6 heptane no no m.p. 54 C., 250 ppm W, 125 ppm Al, 110 ppm Cl 1B EADC/WCl.sub.6 heptane no 5 washing m.p. 54 C., volumes 250 ppm W, 125 ppm Al 2A C3 heptane no no m.p. 30 C., 10 ppm Ru 2B C3 heptane no 5 washing m.p. 30 C., volumes precipitation of grey particles 3A C3 heptane butyl vinyl no m.p. 42 C., ether 3 ppm Ru 3B* C3 heptane butyl vinyl 5 washing m.p. 59 C., ether volumes 1.5 ppm Ru 4A C3 heptane ethyl vinyl no m.p. 40 C., sulfide 5 ppm Ru 4B* C3 heptane ethyl vinyl 5 washing m.p. 57 C., sulfide volumes 2.4 ppm Ru 5A C3 toluene butyl vinyl no m.p. 28 C. ether 5 ppm Ru 5B* C3 toluene butyl vinyl 7 washing m.p. 59 C. ether volumes <1 ppm Ru 6B EADC/WCl.sub.6 heptane butyl vinyl 5 washing m.p. 54 C. ether volumes 250 ppm W, 125 ppm Al, 110 ppm Cl *inventive EADC = Ethylaluminium dichloride, m.p. = melting point

[0109] Polyoctenamer synthesized with tungsten catalyst and subsequently subjected to a membrane filtration shows a melting point below 57 C. High chlorine and metal proportions are also present (cf. example 1B). An addition of an alkyl vinyl ether (example 6B) does not show any change in melting point and metal proportions.

[0110] In the ruthenium-catalyzed production of polyalkenamer a membrane filtration without alkyl vinyl ether results in a precipitation of grey particles with a very low melting point of 30 C. (example 2B). When alkyl vinyl ether or alkyl vinyl sulfide are added without performing a membrane filtration the polymers at 180 C. are not thermally stable (melting point in example 3A: 42 C., example 4A: 40 C., example 5A: 28 C.) and the metal proportion in the polymer is higher.

[0111] The combination of ruthenium catalyst, alkyl vinyl ether addition and membrane filtration results in a polyoctenamer which is thermally stable at 180 C. and has a high melting point of 57 C. or 59 C.