TY - JOUR
T1 - Synthesis and characterization of novel random copolyesters from trans-4-hydroxy-L-proline and functional cyclic esters
AU - Lee, Ren Shen
AU - Lin, Tz Feng
AU - Yang, Jen Ming
PY - 2004/1/1
Y1 - 2004/1/1
N2 - The melt polycondensation reaction of trans-4-hydroxy-N-benzyloxycarbonyl-L-proline (N-CBz-Hpr) and functional cyclic esters containing protected functional groups (carboxyl, and amino) at a wide range of molar fractions in the feed produced new degradable poly(N-CBz-Hpr-co-functional-ε-CL)s with stannous 2-ethylhexanoate (Sn(Oct)2) as a catalyst. The optimal reaction conditions for the synthesis of the copolymers were obtained with 1.5 wt% Sn(Oct)2 at 140 °C for 24 h. The copolymers obtained were characterized by Fourier transform infrared spectroscopy (FT-IR), 1H NMR, differential scanning calorimetry, gel permeation chromatography, and Ubbelohde viscometry. The copolymers synthesized exhibited oligomeric molecular weights (3000-5000 g mol-1) with modestly narrow molecular weight distributions (1.11-1.37). The values of the glass-transition temperature (Tg) of the copolymers depend on the compositions, and the molar fractions of cyclic lactone. For the poly(N-CBz-Hpr-co-4-EtC-ε-CL) system, with a decrease in 4-EtC-ε-CL contents from 79 to 3 mol%, the Tg increased from -34 to 67 °C In vitro degradation of these copolymers was evaluated from weight-loss measurements.
AB - The melt polycondensation reaction of trans-4-hydroxy-N-benzyloxycarbonyl-L-proline (N-CBz-Hpr) and functional cyclic esters containing protected functional groups (carboxyl, and amino) at a wide range of molar fractions in the feed produced new degradable poly(N-CBz-Hpr-co-functional-ε-CL)s with stannous 2-ethylhexanoate (Sn(Oct)2) as a catalyst. The optimal reaction conditions for the synthesis of the copolymers were obtained with 1.5 wt% Sn(Oct)2 at 140 °C for 24 h. The copolymers obtained were characterized by Fourier transform infrared spectroscopy (FT-IR), 1H NMR, differential scanning calorimetry, gel permeation chromatography, and Ubbelohde viscometry. The copolymers synthesized exhibited oligomeric molecular weights (3000-5000 g mol-1) with modestly narrow molecular weight distributions (1.11-1.37). The values of the glass-transition temperature (Tg) of the copolymers depend on the compositions, and the molar fractions of cyclic lactone. For the poly(N-CBz-Hpr-co-4-EtC-ε-CL) system, with a decrease in 4-EtC-ε-CL contents from 79 to 3 mol%, the Tg increased from -34 to 67 °C In vitro degradation of these copolymers was evaluated from weight-loss measurements.
KW - Copolymer
KW - Functional cyclic ester
KW - Trans-4-Hydroxy-L-proline
UR - http://www.scopus.com/inward/record.url?scp=0346788714&partnerID=8YFLogxK
U2 - 10.1016/j.polymer.2003.10.059
DO - 10.1016/j.polymer.2003.10.059
M3 - 文章
AN - SCOPUS:0346788714
SN - 0032-3861
VL - 45
SP - 141
EP - 149
JO - Polymer
JF - Polymer
IS - 1
ER -