Cationic Grafting from Carbon Black. X. Graft Polymerization Initiated by Benzylium Perchlorate Groups Introduced onto a Carbon Black Surface

Abstract

The cationic graft polymerization of various polymers from carbon black initiated by benzylium perchlorate groups introduced onto the surface was investigated. The introduction of benzylium perchlorate groups onto a carbon black surface was achieved by the reaction of silver perchlorate with benzyl chloride groups on the surface. Benzyl chloride groups were introduced by the treatment of carbon black with 3,3′-bischloromethylbenzoyl peroxide in carbon tetrachloride. It was found that the cationic polymerization of styrene is initiated by carbon black having benzylium perchlorate groups, and polystyrene is grafted from the surface based on the propagation of the polymer from the surface. The percentage of grafting increased to 130.1%. The weightaverage molecular weight of grafted polystyrene was estimated to be 5.0 × 10³. Furthermore, benzylium perchlorate groups on carbon black have an ability to initiate the cationic ring-opening polymerization of cyclic ethers, such as tetrahydrofuran and epichlorohydrin, and lactones, such as ε-caprolactone and δ-valerolactone, to give polyether- and polyester-grafted carbon black, respectively. These polymer-grafted carbon blacks gave a stable colloidal dispersion in good solvents for grafted polymer.