Aspects of thermal grafting of acrylonitrile onto ethyl cellulose in homogeneous media

Homogeneous thermal graft copolymerization of acrylonitrile (AN) onto ethyl cellulose (EC) by using ammonium persulfate (APS) as free radical initiator was carried out in the toluene: DMSO solvent system. Many variables affecting the grafting parameters were studied. The effect of using comonomer pairs of acrylonitrile and acrylamide on the grafting yield was examined. Different techniques such as IR and NMR were used. A Trommsdorf effect was observed in certain systems. The rate of graft copolymerization of acrylonitrile onto EC was determined as Rp=0.16% min—1. The higher carbonyl content of thermooxidized EC showed lower grafting yield. The mechanism of the grafting reaction is discussed.