Abstract
Poly(ethylene oxide)/polylatide/poly(ethylene oxide) (PEO/PL/PEO) tri-block copolymers, which each block is connected by ester bond, were synthesized by coupling reaction of PL with PEO in the presence of pyridine. PL/PEO/PL tri-block copolymer was synthesized by ring opening polymerization of L-lactide initiated by PEO in the presence of stannous octoate. Degradation behavior of the copolymers was investigated in a pH 7.4 phosphate buffer saline (PBS) at 37±1°C. Gel permeation chromatography (GPC) and 1H-nuclear magnetic resonance (NMR) were used to monitor the change of mass loss, molecular weight and composition of copolymers. In hydrolytic degradation, the PEO/PL/PEO tri-block copolymer with high PEO contents affected the increase of its mass loss, and resulted in the decrease of its molecular weight as well as PEO composition. However, when PL/PEO/PL and PEO/PL/PEO tri-block copolymers had similar PEO contents, PEO/PL/PEO decreased faster in molecular weight and PEO composition than PL/PEO/PL.
| Original language | English |
|---|---|
| Pages (from-to) | 85-90 |
| Number of pages | 6 |
| Journal | Macromolecular Research |
| Volume | 10 |
| Issue number | 2 |
| DOIs | |
| State | Published - Apr 2002 |
Keywords
- Biodegradable polymer
- Hydrolytic degradation
- Poly(ethylene oxide)
- Polylactide
- Tri-block copolymer