Title:
PROCESS FOR PRODUCING STABILIZED OXYMETHYLENE COPOLYMER
Document Type and Number:
WIPO Patent Application WO/1995/027747
Kind Code:
A1
Abstract:
A process for producing a stabilized oxymethylene copolymer which comprises polymerizing trioxane and a cyclic ether and/or a cyclic formol into an oxymethylene copolymer in the presence of at least one polymerization catalyst selected from the group consisting of boron trifluoride, boron trifluoride hydrate and coordination complex compounds formed between boron trifluoride and organic oxygen or sulfur compounds, evaporating part of the catalyst by heating the reaction system at a temperature below the melting point of the catalyst in an inert gas atmosphere and/or by reducing the pressure of the reaction system without deactivating the catalyst, and stabilizing the molecular ends either after deactivating the remaining catalyst or directly. By reducing the content of the polymerization catalyst remaining in the oxymethylene copolymer, the obtained copolymer is excellent in thermal stability and is reduced in the emission of formaldehyde odor during melt molding.
Inventors:
TANIMURA NORITAKA (JP)
TANIGAWA YUKIO (JP)
KOMATU SUMIO (JP)
TANIGAWA YUKIO (JP)
KOMATU SUMIO (JP)
Application Number:
PCT/JP1995/000579
Publication Date:
October 19, 1995
Filing Date:
March 28, 1995
Export Citation:
Assignee:
ASAHI CHEMICAL IND (JP)
TANIMURA NORITAKA (JP)
TANIGAWA YUKIO (JP)
KOMATU SUMIO (JP)
TANIMURA NORITAKA (JP)
TANIGAWA YUKIO (JP)
KOMATU SUMIO (JP)
International Classes:
C08F2/18; C08G2/18; (IPC1-7): C08G2/18
Foreign References:
| JPS62119219A | 1987-05-30 | |||
| JPS58152012A | 1983-09-09 |
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