Trihydroxyethyl isocyanuricate(THEIC) using as initiator, trifunctionality glycidyl azide polymer(TGAP, M_n=2500~3000) with nitrogen heterocyclic ring structure was synthesized by cationic ring-opening polymerization of epichlorohydrin and azidation with NaN₃. A novel azide binder glycidyl azide-b-(3-azidomethyl-3-methyl oxetane) copolymers(P(GA-b-AMMO)) were synthesized by polymerization of 3-azidomethyl-3-methyloxetane (AMMO), using TGAP as a macromolecular initiator, and its structures were characterized by Flourier transform infrared spectroscopy(FTIR), nuclear magnetic resonance(¹H NMR and ¹³C NMR) and gel permeation chromatograph(GPC). The effect of polymerization temperature and ratio of materials on the polymerization were investigated. The appropriate polymerization conditions were as fllow: n(BF₃·OEt₂)/n(TGAP)/n(AMMO)=1.35/1/12~16, the polymerization temperature was 0-3 ℃. The results show that the polymerization is controllable in this appropriate polymerization conditions. The total yield of polymers are above 80.0%, functionality ≥ 2.70 and M_n (4000~4400) are closed to theoretical value corresponding. The mechanical test indicated that P(GA-b-AMMO) had better mechanical property compared with TGAP homopolymer. The mechanical strength of P(GA-b-AMMO) /IPDI is 2.04 MPa. The elongation could reach 261%(20 ℃), which is about three times as much as TGAP/IPDI.