Phosphorylation of the cellulose surface with PCl3 and P(O)Cl3

The vapor-phase phosphorylation of cellulose by means of phosphorus trichloride (PCl₃) and phosphorus oxychloride (POCl₃) is presented. It was found that cellulose-O-dichlorophosphines (Cell-O⁶-PCl₂) formed by the reaction of cellulose with PCl₃ and cellulose-O-dichloro-oxyphosphines (Cell-O⁶-P(O)Cl₂) formed by the reaction with P(O)Cl₃ have been hydrolyzed to cellulose-O-hydrogenphosphates (P(III/V)) (Cell-O⁶-P(O)(H)-OH and (Cell-O⁶-P(O)(OH)₂), respectively. Selected chemico-physical properties (SEM-EDS, ³¹P NMR, potentiometric titration) of both types of cellulose phosphates (Cell-O⁶-O-P(O)(H)-OH and Cell-O⁶-O-P(O)(OH)₂) were compared.