Abstract
Triblock copolymers based on tetrahydrofuran (THF) and 3,3‐bis(chloromethyl) oxetane (BCMO), BCMO‐block‐THF‐block‐BCMO and poly(BCMO‐co‐THF)‐THF‐(BCMO‐co‐THF), have been synthesized by two‐end living cationic polymerization with a bifunctional initiator, trifluoromethanesulfonic anhydride [(CF 3 SO 2 ) 2 O]. The polymers are obtained by using the two end propagating species of poly(THF) to initiate the sequential BCMO polymerization. The resulting polymers are characterized by infrared (IR), nuclear magnetic resonance (NMR), and differential scanning calorimetry (DSC), confirming that the polymers are ABA‐type block copolymers. The identities of the molecular weights predetermined and which determined by GPC show the success of predetermining molecular weights of the polymers and preparing well‐defined polymers. The narrow polydispersities, 1.1–1.3, indicate that the chains are propagating by a living mechanism. © 1993 John Wiley & Sons, Inc. Copyright © 1993 John Wiley & Sons, Inc.