The use of loomstate cotton fabric (starch sized fabric) as a substrate for grafting of methacrylic acid using KMnO,/ citric acid as initiator provided an effective method with greater potentiality. Presence of starch size on the fabric helps the deposition of MnO, over the fabric with subsequent acceleration of the grafting reaction. Major factors affecting polymerization of MAA, such as KMnO,, citric acid and MAA concentrations, as well as reaction time and temperature of polymerization were studied. A tentative mechanism for the polymerization reaction is suggested. Eeschleunigung der durch das Initiatorsystem KMn0,lZitronensaure induzierten Pfropfung uon Methacrylsaure a u f Baurnwollrohgewebe durch die Starkeappretur Der Einsatz von Baumwollrohgewebe (mit Starke geschlichtetes Gewebe) als Substrat fur die Pfropfung von Meth-acSylsaure mit dem Initiatorsystem KMnOp/Zitronensaure ist eine effektive Mcthode mit weitreichenden Anwendungsmoglichkeiten. Die Anwesenheit der Starke auf dem Gewebe begunstigt die Ablagerung von MnO, und damit die Be, schleunigung der Pfropfreaktion. Die wichtigsten Faktoren, die die Polymerisation der Methacrylsaure beeinflussenwie die Konzentrationen des Kaliumpermanganats, der Zitronensaure und des Monomers, sowie die Reaktionszeit und die Temperatur wurden untersucht. Ein Mechanismus der Polymerisationsreaktion wird vorgeschlagen. Y m o p e n u e x p a x m a m n a f i annpemom npoyecea n p u s u s m memalipunoaoii mehornbc K cyposoii x n o n r a m o 6 y~a~n o i L m x a n u , unuyuupyemoii cucmefioii KMn0,lnufionHafi m c n o m akICIIOJIb3OBaHHe CypOBOfi XJIOIIqaTO6yMaXHOfi TKaHH (IIIJIHXTOBaHHOfi KpaXMaJIOM) KBK c y 6 c~p a~ AJIFI npHBHBKH MeTaKpHJIOBOfi KHCJIOTbI B IIp&ICyTCTBHH CMCTeMbI HHHqHaTOpa KMnO,/n&IMoHHasI KHCJIOTa IIpeACTaBJIFIeT c060fi 3@@eKTHBHbIfi MeTOA C IIIHPOKIlMH B03MOXHOCTFIMH IIpHMeHeHHff. npHCyTCTBHe KpaXMaJIa H a TKaHH CnOC06CTByeT OTJIOXeHHIO MnO, H, TeM CaMbIM, YCKOpeHHIO PeaKqHH IIPHBHBKH. M3J"leHbI ~a~6 o n e e BaXHbIe @aKTOpbI BJIHRHHFI Taxme npononmmenbHocTb EI TeMnepaTypa peaKqm. npennaraeTcx M~X~H H~M peaHqm n o n~~e p~3 a q a~. EL SISI, ABDEL HAFIZ e t al. : Starch size in loomstate cotton fabric accelerates grafting of methacrylic acid 15 30 60 90 120 Acta Polymerica 41 (1990) Nr. 6

Carboxymethyl cellulose (CMC) was treated with HCl at 8OoC for different time periods (15-60 min). The hydrolyzed CMC samples as well as the original sample were graft copolymerized with acrylamide using &qQ as initiator. It was disclosed that the increasing duration of acid hydrolysis is accompanied by a progressive increment in the copper number of CMC, meanwhile its carboxyl content decreases. Acid hydrolysis enhances significantly the susceptibility of the CMC toward grafting. The latter reduces the copper number of the hydrolyzed CMC samples most probably via conversion of the aldehydic to carboxylic groups under the action of &&Q during grafting. Grafting also reduces the carboxyl content of the original CMC sample while increasing those of the hydrolyzed CMC samples. Methylolation of the polyacrylamide-CMC graft copolymers results in reactive finishes. When the latter were applied to cotton fabric according to the conventional pad-dry-cure method followed by a thorough washing, the fabric retained ca. 86% of the finish derived from the copolymer of CMC and 92% of finishes derived from the copolymers of hydrolyzed CMC. ZUSAMMENFASSUNG:Carboxymethylcellulose (CMC) wurde bei 80 "C unterschiedlich lange (15 -60 min) mit HCl behandelt. Sowohl die hydrolysierten CMC-Proben als auch die urspriingliche Probe wurden mit Acrylamid unter Verwendung von &qQ als Initiator gepfropft. Es zeigte sich, daR mit zunehmender Hydrolysezeit die Kupferzahl der CMC anstieg, wtlhrend der Carboxylgehalt dagegen abnahm. Die saure Hydrolyse erhshte die Empfindlichkeit der CMC gegeniiber Pfropfung bedeutend. Die Pfropfung redu-* Part 11: cf. ref?.

SYNOPSISGraft polymerization of methacrylic acid (MAA) to loomstate viscose fabric (greige fabric) using KMnO4/NaC1O2 system was studied. Residual thiocarbonate and/or sizing materials on the fabric as well as presence of NaCIOz act in favor of primary radical formation which, in turn, accelerate formation of cellulose macroradicals capable of initiating grafting. The polymerization reaction was studied with respect to polymer yield, graft yield, homopolymer, total conversion, and graft efficiency. The magnitude of each of these characteristics was found to depend upon parameters such as concentrations of KMn04, NaC102, and MAA as well as liquor ratio, reaction time, and temperature of polymerization. By and large all these parameters enhance the polymerization process with the exception of the liquor ratio.A reaction mechanism for the polymerization reaction is also reported. 0 1995 John Wiley & Sons, Inc.

tend; hierbei wurde mit Isopropanol die hdchste Steigerung erhalten. Hdhere Alkoholmengen dagegen erniedrigten die Ausbeute. Die Pfropfgeschwindigkeit ist anfangs hoch, spater wird die Pfropfungsreaktion langsamer. Unabhingig von den verwendeten Reaktionsbedingungen war eine Reaktionszeit von 60 Minuten ausreichend. Es wurde die Fahigkeit des Cdv-Cellulosethiocarbonats untersucht, die Pfropfung mit Methylmethacrylat, Acrylnitril und Acrylamid zu initiieren. Dabei ergab sich fur die Pfropfgeschwindigkeit folgende Reihenfolge: Methylmethacrylat > Acrylnitril > Acr ylamid .

The polymerization of acrylic acid by the redox system ammonium persulphate/sodium sulphite was studied under a variety of conditions. The obtained results indicate that the total conversion is determined by the concentrations of (NH4)2S2O8 and Na2SO3, as well as by the degree of neutralization of acrylic acid and the duration of polymerization. The apparent viscosity of the formed poly(acrylic acid) decreases as the shear rate increases due to the deformation of the poly(acrylic acid) macromolecules under the influence of higher shear rate. A tentative mechanism for the polymerization reaction is suggested.