| 摘要 |
PURPOSE:To obtain a high-MW copolymer suitable for extrusion molding or blow molding, by feeding formaldehyde, a cyclic formal and a specified inert organic solvent to a twin-screw blender and copolymerizing the mixture in the presence of boron trifluoride. CONSTITUTION:Formaldehyde, a cyclic formal and 0.1-20pts.wt., per 100pts.wt. formaldehyde, following inert organic solvent are continuously fed to a twin- screw blender, and the formaldehyde is copolymerized with the cyclic formal in the presence of boron trifluoride or its etherate complex. As said inert organic solvent, a mixture of an aromatic hydrocarbon with an aliphatic hydrocarbon is used. Examples of the cyclic formals used include ethylene oxide and tetrahydrofuran and these are used in an amount of 0.001-0.1mol per mol of the formaldehyde feed.
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