Allyl poly (ethylene glycol) block copolymer(PEG-PGA-PAGE) was synthesized by cationic ring-opening polymerization using polyethylene glycol (PEG) as initiator, BF3•Et2O complex as catalyst, glycidyl ether (GA) and allyl glycidyl ether (AGE) as monomers. The product structure was characterized by FTIR and 1HNMR. The mechanical properties and thermal properties of two elastomers (PEG-PGA- PAGE-1 and PEG-PGA-PAGE-2) prepared by curing binders prepared by adding GA and AGE separately and simultaneously with terephthalonitrile oxide were investigated. The results showed that the binder can cure at room temperature, the cured elastomer PEG-PGA-PAGE-1 prepared by subsection addition of GA and AGE had better mechanical properties and thermal properties. Its tensile strength was 0.948 MPa, elongation at break was 89.32%, shaw hardness was 23.8 Ha, storage modulus reached 361.05 MPa, Tg was -41.85℃, contact angle was 74°. Room temperature curing improved the mechanical properties, which is expected to be used in composite solid propellants. © 2019, Editorial Office of FINE CHEMICALS. All right reserved.