Cross‐linking agents for the protection of lyocell against fibrillation: synthesis, application and technical assessment of 2,4‐diacrylamidobenzenesulphonic acid

A novel, colourless, water soluble, anionic cross‐linking agent, 2,4‐diacrylamidobenzenesulphonic acid, has been synthesised, applied to lyocell by a pad–steam method and the wet abrasion resistance measured. The agent furnished cross‐linked lyocell fibres with good wet abrasion resistance and stable lyocell–agent bonds to subsequent hot exhaust reactive dyeing conditions. Surprisingly, the fibre–agent bonds showed some instability to polyester dyeing conditions at pH 4.5 and 5.0. This is rationalised in terms of hydrolysis of the amide bond ortho to the sulphonic acid group via a neighbouring group participation mechanism.