| 摘要 |
1,219,777. Fire-resistant films and filaments. EASTMAN KODAK CO. 21 Nov., 1968 [29 Nov., 1967], No. 55199/68. Heading B5B. [Also in Division D1] A film or filament of a polyester derived from a bifunctional hydroxycarboxylic acid or from (A) carbonic acid or a bifunctional carboxylic acid and (B) a bifunctional diol, which polyester contains H atoms attached to non-aromatic C atoms which are themselves attached to only C or H, is chlorinated on its surface at these H atoms at a temperature of ambient up to 150‹ C. to a C<SP>1</SP> content of at least 2% by wt. Many polyesters are exemplified; their components may be aliphatic, alicyclic or aromatic, long lists being given. Chlorination may be via chlorine (gaseous or in solution), sulphuryl chloride, phosphorus pentachloride or organic or inorganic hypochlorites. A chlorination promoter is used, e.g. benzoyl peroxide, azobisisobutyronitrile, H 2 O 2 , an alkali metal persulphate, heat or visible or U.-V. light. |
