Design, synthesis and fibre-reactivity study of a water-soluble, monochloro-s-triazinyl hindered nitroxide on mechanical pulps

A water-soluble hindered nitroxide possessing a monochloro-s-triazinyl group was designed and synthesized from 4-amino-2,2,6 6-tetramethylpiperidinyloxy (4-arnino-TEMPO). The structure of this nionochloro-s-triazinyl hindered nitroxide was established by FTIR, H-1 NMR, MS and elemental analyses of its dithionite-reduced, hydroxylamine derivative. It retains the yellowing inhibition ability of its precursor nitroxide, 4-amino-TEMPO, when applied onto the surface of a spruce bleached thermomechanical pulp (BTMP) sheet. Its fibre-reactivity towards the BTMP fibres is, however, very low at less than or equal to 80 degreesC and pH less than or equal to 10.5. (C) 2003 Elsevier Ltd. All rights reserved.