A tri-arm block copolymer

polyethylene glycol/tetrahydrofuran copolyether

was synthesized with tri-arm polyethylene glycol and tetrahydrofuran as main raw materials and boron trifluoride ether as catalyst by means of cationic ring-opening polymerization in this research. The effects of some factors such as reaction time

raw material ratio

dosages of catalyst and ring-opening assistant on the hydroxyl value of synthesized block copolyether were examined through orthogonal test. The better synthesis condition for tri-arm block copolyether with higher molecular weight was obtained. The synthesized copolyether was characterized through infrared spectroscopy

gel permeation chromatography and nuclear magnetism resonance test.