Hetero-Multifunctional Poly(ethylene glycol) Copolymers with Multiple Hydroxyl Groups and a Single Terminal Functionality.

Hetero-multifunctional poly(ethylene glycol-co-glycerol) random copolymers with multiple hydroxyl functionalities and a single terminal functionality have been prepared by copolymerization of ethylene oxide (EO) and ethoxy ethyl glycidyl ether (EEGE) with the use of a suitable initiator, introducing a protected amino group or a double bond, respectively. Acidic deprotection was used for removal of the acetal protecting groups in the chain, and the terminal amino group was regenerated by catalytic hydrogenation. A series of copolymers with narrow polydispersity was obtained, varying comonomer fractions from 3 to 67% and molecular weights in the range of 5 000―32 000 g·mol ―1 (1.05 < M w /M n < 1.25). Molecular and thermal characterization was carried out using 1 H- and 13 C NMR, SEC and differential scanning calorimetry (DSC).