الفهرس | Only 14 pages are availabe for public view |
Abstract Su.mm.a.r-y In the present work, the linen fibres were chosen as a non conventional source of the cellulosic fibres used for different reactions. The linen fibres were treated with different concen trations of sodium hydroxide at different temperatures followed by treatments with various bleaching agents, i.e, sodium chlorite, sodium hypochlorite and sodium chlorite/potassium permanganate mixture. The obtained samples were investigated fo:- their reactivi ties towards xanthation and acetylation, thermal behaviour and the structure has been inv2stigated using X-ray and I.R techniques. It was found that, treatment with sodium hydroxide, either at low or high temperatures, has a 1imi ted effect on the lignin, hemicellulose and a-cellulose contents. Different bleaching agents differently affected the lignin content, and ·ather chemical ccnst:i tmmts which may be related to either the effect: of alkall pL·etreatment or to the effect of the bleaching agents used. It is also found that, although alkali pretreat ment at 120’C has no significant effect on the chemical constituents of the samples, yet, bleaching of these samples affected to a great extent ir chemical constituents. |