| 초록 |
Poly(L-lactic acid)-b-poly(ethylene glycol) (PLLA-b-PEG) star branched block copolymers were synthesized using a hexachlorocyclotriphosphazene core. N3P3(OC6H4-p-CHO)6 was prepared by the reaction between the hexachlorocyclotriphosphazene core and 4-hydroxybenzaldehyde sodium salt, obatined by the reaction of 4-hydroxybenzaldehyde and sodium hydride. Further, N3P3(OC6H4-p-CH2OH)6 was obtained by the reduction reaction of N3P3(OC6H4-p-CHO)6 with sodium borohydride. A series of PLLA star branched polymers was synthesized by polymerizing lactide using N3P3(OC6H4-p-CH2OH)6 as initiator. Esterification was carried out for producing carboxylated PLLA by using succinic acid. PLLA-b-PEG star branched block copolymers were prepared by additional esterification with poly(ethylene glycol methyl ether) and characterized with 1H NMR, DSC, AFM, TEM, SEM. |
