Addition of bulky C60moiety to the poly(vinylbenzylchloride) (PVBC) by a novel organometallic reaction modifies greatly the chemical and physical properties of this polymer. It is found that the product, which has a visibly brownish-yellow cast when compared with the unreacted polymer, is soluble in some common organic solvents. In this product, there are mainly two kinds of paramagnetic species, a narrow ESR signal (g= 2.0026, Δ Hpp = 1.8 G, T2= 3.64 × 10−8sec) attributed to the charge-transfer interaction between the pendant C60molecule and the corresponding near-neighbor chlorobenzyl (-C6H5CH2Cl) groups in polymer, and a shoulder broad signal (Δ Hpp = 12.0 G) which is assigned to the positively charged chlorobenzyl groups and the adjacent relatively electron-rich chlorobenzyl groups. Also, the effect of the ultraviolet irradiation on the paramagnetic electronic structure of the product has been studied. © 1997 Elsevier Science Ltd. All rights reserved