Because of the two functional groups in their polymer chain ends, telechelic polymers are usually used for the preparation of copolymers with special structures, such as block, graft, star-like, hyperbranched copolymers. Telechelic polymers are mainly prepared by traditional radical polymerization, controlled/“living” radical polymerization, anionic polymerization, cationic polymerization, metathesis polymerization, and condensation polymerization, etc. In comparison with traditional polymerization methods, olefin metathesis polymerization can be conducted in milder conditions and the molecular weight and structure of products are more controllable. In this review, the preparation of telechelic polymers via ring-opening metathesis polymerization (ROMP) and acyclic diene metathesis (ADMET) polymerization in the presence of chain transfer agents are introduced. And the preparation of block copolymers via the combination with other living polymerization methods (such as NMRP, ATRP, RAFT, ROP, etc.) will be also included.

Contents
1 Introduction
2 Catalysts for olefin metathesis polymerization
3 Telechelic polymers via olefin metathesis polymerization
3.1 ROMP
3.2 ADMET polymerization
4 Block copolymers via the combination with other living polymerization methods
4.1 Combination of ROMP and NMRP
4.2 Combination of ROMP and ATRP
4.3 Combination of ROMP and RAFT
4.4 Combination of ROMP and ROP
5 Conclusion