5-Ethylidene-2-norbornene (ENB) polymerization and copolymerization with ethylene (E) catalyzed by constrained geometry catalyst 2-tetramethylcyclopentadienyl-4,6-di-tert-butylphenoxytitanium dichloride (1) were studied in the presence of (AlBu3)-Bu-i and Ph3CB(C6F5)(4) (TIBA/B). The catalyst system shows moderate activity on the homopolymerization of ENB, and higher activity on the copolymerization of E/ENB under atmospheric pressure of ethylene. H-1 NMR analysis indicates that ENB was regioselectively incorporated into the copolymer backbone through the endocyclic double bond, leaving the ethylidene double bond unreacted. The ethylidene group contained in the poly(E-co-ENB) was quantitatively converted to the epoxy group with in-chloroperbenzoic acid, producing functionalized poly(E-co-ENB)s. The parent and functionalized copolymers have been characterized using IR, NMR, DSC, and GPC techniques. (C) 2008 Elsevier Ltd. All rights reserved.