Tetrakis(hydroxymethyl)phosphonium chloride124-64-1100 % similar Tetrakis(hydroxymethyl)phosphonium sulfate55566-30-843 % similar (Hydroxymethyl)triphenylphosphonium chloride5293-83-438 % similar Tetrakis(hydroxymethyl)phosphonium chloride-urea polymer27104-30-933 % similar