1992 Volume 65 Issue 4 Pages 220-225
It was found that the polymerization of vinyl monomers, such as acrylamide (AAm), acrylic acid, and acrylonitrile, is initiated by a redox system consisting of ceric ion and acetylene black. The monomers were effectively graft polymerized onto the surface of acetylene black : The percentage of PAAm grafting onto acetylene black was increased with increasing conversion, and PAAm-gel-containing acetylene black was obtained at the conversion of about 30% or more. However, the system consisting of ceric ion and other carbon blacks having surface-oxygen-containing groups, such as furnace and channel blacks, failed to initiate the polymerization. Furthermore, carbon whisker and graphite powder had an ability to initiate the redox polymerization in the presence of ceric ion to give polymer-grafted carbon whisker and graphite powder. The relationship between the polymerization rate (Rp) and the concentration of acetylene black ([CB]), ceric ion ([Ce (IV)]), and AAm ([M]) was found to be given by the following equation : Rp=k [C13] 2 [Ce (IV)] [M]. The wettability and dispersibility of acetylene black were found to be remarkably improved by the surface grafting of polymers.
