Behavior of cellulose grafted with poly(methyl methacrylate) and polyacrylonitrile toward some direct and reactive dyes

Abstract

SynopsisViscose rayon fibers modified with polyacrylonitrile (PAN) and poly(methy1 methacrylate) (PMMA) were dyed with some direct and reactive dyes. Exhaustion rate of the dye onto fibers was governed by the amount and nature of the polymer grafted. In general, the dye affinity for cellulose and dye exhaustion onto fibers decreased as the graft yield increased. Dye affinity for the PAN-cellulose graft copolymers was greater than that found with PMMA-cellulose graft copolymers. Except in a few cases, the tendency of cellulose graft copolymers of ca. 13% graft to accept direct dyes was more than that of the untreated cellulose, whereas the affinity of reactive dyes for cellulose graft copolymers of up to ca. 43% polymer was more than that of untreated cellulose. The dye fixation, based on the weight of cellulose component, increased as the graft yield increased. The dyeability of cellulose oxidized with ceric ammonium nitrate was also examined. Oxidation of cellulose prior to dyeing reduced the affinity of the dye for cellulose.

Behaviour of chemically modified cottons towards thermal treatment. Part III. Poly(acrylonitrile)‐cellulose graft copolymers

“…Figure 4 shows the effect of heat treatment a t 160°C for different periods of time (3 t o 24 h) on the nitrogen content of poly(AN)-cellulose graft copolymers (substrates 111, IV and V). I t is clear that the nitrogen content of the copolymers before thermal treatments amounts t o 1.7y0, 2.5% and 4.6%. Figure 4 shows that subjecting the poly(AN)-cellulose graft copolymers to heat treatment brings about a decrease in the nitrogen content of the copolymers.…”

The effect of grafting on the dyeability and properties of some modified celluloses

“…It is observed from table 2 that affinity of cross-linked celluloses for Chlorazol Sky Blue FF is low, while oxycelluloses show lower dye affinity than standard cellulose. These results indicate that conversion of hydroxyl groups to aldehydes and carboxyl groups, and loss of hydroxyl groups by cross-linking led to reduction of dye affinity of substrates (17,18,19). Negatively charged carboxyl groups on the fabric repel similarly charged dye molecules, which decreases dye affinity of the fabric.…”

Μελετη Βαφης Βαμβακερων Και Χημικως Τροποποιημενης Κυτταρινης Με Απευθειας Χρωματα

“…Στη συνέχεια, πλύθηκε με μεθανόλη, μετά με νερό και πάλι με μεθανόλη. Τέλος εκχυλίσθηκε σε συσκευή Soxhlet για 24 ώρες με μεθανόλη, για την απομάκρυν ση του μονομερούς και του ομοπολυμερούς, ξηράνθηκε σε πυριαντήριο 80 ± 2 °C για 15 min, ζυγίστηκε και από την αύξηση του βάρους του δείγματος (~ 0.04 g) βρέθηκε το ποσόν της βινυλοπυριδίνης που εμβολιάστηκε 135 και υπολογίστηκε ως % εμβολια σμός: τελικό βάρ. υφάσματος -αρχικό βάρ.…”