| abstract |
A polymeric material, particularly textile fibres such as cotton and wool, which has flame-retardant char-forming properties is treated to improve flame-retardance by substitution of active hydrogens of the polymeric material with a phosphoryl substituent. The active hydrogens may be active hydrogens of the polymeric material and/or active hydrogens of an incorporated char-former such as a polyphosphine oxide or an N-methyloldimethyl phosphonopropionamide. The phosphoryl substituent may be derived from a cyclic polyol phosphoryl chloride such as spirocyclic pentaerythritol diphosphoryl chloride, a sorbitol phosphoryl chloride, a pentaerythritol phosphoryl chloride or a glycerol phosphoryl chloride. |