| 摘要 |
Polyoxymethylenes are prepared by polymerizing formaldehyde in the presence of metallic aluminium, an aluminium alloy, aluminium oxide, aluminium hydroxide, or hydrated aluminium oxide. When aluminium or aluminium alloy is used it may be activated by treatment with a solution of mercury salt. The polymerization may be performed with or without a solvent at -80 DEG to +70 DEG C. In examples formaldehyde is polymerized in vessels containing small aluminium plates activated by treatment with mercuric chloride, aluminium alloys, hydrated aluminium oxide in toluene, aluminium oxide prepared from aluminium alloys in toluene, and aluminium hydroxy chloride in toluene. |
