Process for preparing polyalkenamers for packaging applications
A process has the ability to produce polyalkenamer-containing compositions. Stages of the process include converting at least one cycloalkene by ring-opening metathetic polymerization to obtain a polyalkenamer-containing product mixture, and working up the product mixture to remove at least one of a monomer and an oligomer of the at least one cycloalkene to obtain the polyalkenamer-containing composition. The working up stage is effected by a diafiltration.
1. A process for producing a polyalkenamer-containing composition, the process comprising:
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 at least one of a monomer and an oligomer of the at least one cycloalkene to obtain the polyalkenamer-containing composition, wherein
said b) working up comprises a diafiltration.
2. The process according to claim 1 , wherein a membrane for a membrane filter for the diafiltration comprises at least one separating layer selected from the group consisting of a polymer, glass, metal, and ceramic.
3. The process according to claim 1 , wherein the cycloalkene is at least one member 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, and dicyclopentadiene.
4. The process according to claim 1 , wherein the polyalkenamer-containing product mixture comprises a solvent and the diafiltration is conducted in said solvent.
5. The process according to claim 1 , comprising converting the polyalkenamer-containing product mixture to a solid form and bringing said polyalkenamer-containing product mixture back into solution for subsequent conduction of the diafiltration.
6. The process according to claim 1 , wherein said a) converting is carried out in the presence of a catalyst.
7. The process according to claim 1 , wherein said a) converting is carried out in the presence of a chain transfer agent.
8. The process according to claim 1 , wherein at least one solvent is present during diafiltration, wherein said at least one solvent comprises at least one stabilizer.
9. The process according to claim 1 , wherein
said a) converting is carried out in the presence of a catalyst that comprises at least one member selected from the group consisting of:
a compound comprising at least one transition metal halide and an organometallic compound; and
a compound comprising at least one transition metal-carbene complex.
10. The process according to claim 1 , wherein
said a) converting is carried out in the presence of at least one chain transfer agent selected from the group consisting of:
an acyclic alkene comprising at least one non-conjugated double bond; and
a cyclic compound comprising a double bond in a side chain thereof.