SYNTHESIS OF POLY(ETHER-ESTER) WITH PEG S ELECTIVELY GRAFTED ONTO DIFFERENT SEGMENTS AND ITS ANTITHROMBOGENICITY

alpha-Methyl-omega-(2,3-epoxy)propyl poly(ethylene glycol)(II) was hyd rolyzed to a glycol(II) with a pendent poly(ethylene glycol) (PEG) cha in, Poly(ether-ester) (PEEs) with PEG grafted onto the hard segments ( H-PEEs) was synthesized by reacting the glycol(II), terephthaloyl chlo ride and poly(butylene glycol). The macromer(II) cationically copolyme rized with tetrahydrofuran to give a copolyether (N) grafted with PEG. Using copolyether(N) having an average 1.25 grafts per molecule, the S-PEEs with PEG grafted onto soft segments was synthesized, The recalc ification time for S-PEEs remained almost unchanged in comparing with ungrafted PEEs, while that for H-PEEs increased by about 100% even tho ugh the hydrophicilities both of S-PEEs and H-PEEs were raised signifi cantly.