"Tree-shaped" copolymers constituted by an m-PEG trunk and poly(L-lactide) or poly(D,Llactide) branches were obtained. The m-PEG was functionalized at the terminal chain with two (G1) and four (G2) hydroxyl groups, then reacted with Al(CH3)3 to produce aluminum alkoxide species, active as initiators in the ROP of L- or D,L-lactide. Copolymers were characterized by 1H and 13C NMR, GPC and DSC, and compared with analogous linear copolymers. Characterization of a low-molecular-weight G1 copolymer confirmed the architecture. GPC curves showed monomodal and narrow molecular weight distribution for all the samples, while the melting points of the copolymers seemed more correlated to the architecture than to the composition. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
"tree-shaped" copolymers based on poly(ethylene glycol) and atactic or isotactic polylactides: Synthesis and characterization
IZZO, LORELLA
;
2010-01-01
Abstract
"Tree-shaped" copolymers constituted by an m-PEG trunk and poly(L-lactide) or poly(D,Llactide) branches were obtained. The m-PEG was functionalized at the terminal chain with two (G1) and four (G2) hydroxyl groups, then reacted with Al(CH3)3 to produce aluminum alkoxide species, active as initiators in the ROP of L- or D,L-lactide. Copolymers were characterized by 1H and 13C NMR, GPC and DSC, and compared with analogous linear copolymers. Characterization of a low-molecular-weight G1 copolymer confirmed the architecture. GPC curves showed monomodal and narrow molecular weight distribution for all the samples, while the melting points of the copolymers seemed more correlated to the architecture than to the composition. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.