Graft copolymerization of acrylic acid onto methylcellulose by potassium permanganate-p-xylene redox pair

Authors

  • C. O. Eromosele,

    Corresponding author
    1. Department of Chemistry, University of Agriculture, P. M. B. 2240, Abeokuta, Ogun State, Nigeria
    • Department of Chemistry, University of Agriculture, P. M. B. 2240, Abeokuta, Ogun State, Nigeria
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  • S. P. Nwokata

    1. Department of Chemistry, University of Agriculture, P. M. B. 2240, Abeokuta, Ogun State, Nigeria
    Current affiliation:
    1. Federal University of Technology, Yola, Nigeria
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Abstract

Poly(acrylic acid) was grafted onto methylcellulose in aqueous media by a potassium permanganate-p-xylene redox pair. Within the concentration range from 0.93 × 10−3 to 9.33 × 10−3M, p-xylene, the graft copolymerization reaction exhibited minimum and maximum graft yields and was associated with two precursor-initiating species, a p-xylyl radical and its diradical derivative. The efficiency of the graft was low, not higher than 12.9% at a p-xylene concentration of 0.93 × 10−3M and suggested the dominance of a competitive homopolymerization reaction under homogeneous conditions. The effect of permanganate on the graft yield was normal and optimal at 135% graft yield, corresponding to a concentration of the latter of 33.3 × 10−3M over the range from 8.3 × 10−3 to 66.7 × 10−3M. The conversion in graft yield showed a negative dependence on temperature in the range 30–60°C and suggested a preponderance of high activation energy transfer reaction processes. The calculated composite activation energy for the graft copolymerization was 7.6 kcal/mol. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 278–281, 2004

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