Process for preparing polyalkenamers for packaging applications

Patent metadata

Field	Value
Publication number	US-2020002467-A1
Application number	US-201816484711-A
Country	US
Kind code	A1
Filing date	Feb 9, 2018
Priority date	Feb 10, 2017
Publication date	Jan 2, 2020
Grant date	—

Abstract

The present invention relates to a process for producing cycloalkenamer-containing compositions, comprising the steps of:
a) converting at least one cycloalkene by ring-opening metathetic polymerization to obtain a polyalkenamer-containing product mixture, and b) working up the product mixture to remove monomers and oligomers of the cycloalkenes to obtain the polyalkenamer-containing composition by extraction with CO 2 , whereby the polyalkenamers are polymers of cycloalkenes which comprise at least five cycloalkane monomer units, wherein the extraction comprises at least two stages: b0) an extraction with liquid CO 2 , then b1) an extraction with supercritical CO 2 , then b2) an extraction with gaseous CO 2 , then b0) an extraction with liquid CO 2 , then and then b3) an extraction with supercritical CO 2 .

First claim

1 . A process for producing a polyalkenamer-containing composition, comprising the steps of:
a) converting at least one cycloalkene by ring-opening metathetic polymerization to obtain a polyalkenamer-containing product mixture, and b) working up the product mixture to remove monomers and oligomers of the cycloalkenes to obtain the polyalkenamer-containing composition by extraction with CO 2 , wherein the polyalkenamers are polymers of cycloalkenes which comprise at least five cycloalkane monomer units, wherein the extraction comprises at least the consecutive stages: b0) an extraction with liquid CO 2 , b1) an extraction with supercritical CO 2 , b2) an extraction with gaseous CO 2 , b0) an extraction with liquid CO 2 , and b3) an extraction with supercritical CO 2 .

2 . The process according to claim 1 , wherein extraction in stage b2 is conducted at a temperature in the range from 0° C. to 99° C. and a pressure in the range from 0 bar to 73 bar, with adjustment of pressure and temperature with respect to one another such that the CO 2 remains in gaseous form.

3 . The process according to claim 2 , wherein the pressure is below and the temperature is above the critical value for CO 2 .

4 . The process according to claim 1 , wherein the extraction in stages b1 and b3 is conducted at a temperature in the range from 31° C. to 99° C. and a pressure in the range from 74 bar to 1000 bar.

5 . The process according to claim 1 , wherein the relative mass throughput is between 10 kg and 500 kg of CO 2 per polyalkenamer-containing product mixture.

6 . The process according to claim 1 , wherein a separation of the CO 2 extractant from monomers and oligomers is effected after step b3.

7 . The process according to claim 6 , wherein the CO 2 for separation is gaseous.

8 . The process according to claim 6 , wherein the CO 2 for separation is supercritical and an adsorbent takes up the monomers and oligomers.

9 . The process according to claim 8 , wherein the adsorbent is selected from activated carbon, alumina, silica and mixtures.

10 . The process according to claim 1 , 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-norbornene, 5-ethylidene-2-norbornene, dicyclopentadiene and mixtures thereof.

11 . The process according to claim 1 , wherein the polyalkenamer-containing product mixture obtained in a) is in solid form and is granulated or pulverized to particles prior to step b).

12 . The process according to claim 1 , wherein the conversion of cycloalkenes is conducted in the presence of a catalyst, preferably comprising at least one transition metal halide and an organometallic compound or comprising at least one transition metal-carbene complex.

Assignees

• Evonik Degussa Gmbh

Inventors

• Wursche Roland
• Schwager Florian
• Dieter Adam
• Franz Michlbauer

Classifications

• C08J3/12

  Powdering or granulating · CPC title

• C08G2261/418

  Ring opening metathesis polymerisation [ROMP] · CPC title

• C08G2261/11

  Homopolymers · CPC title

• C08G2261/3322

  derived from cyclooctene · CPC title

• C08G2261/71

  Purification · CPC title