Hydrolytic kinetics of biodegradable polyester monolayers

Journal Article · Tue Apr 04 04:00:00 EDT 2000 · Langmuir

DOI:https://doi.org/10.1021/la990800r· OSTI ID:20075524

Lee, W K; Gardella, Jr, J A

The rate of hydrolysis of Langmuir monolayer films of a series of biodegradable polyesters was investigated at the air/water interface. The present study investigated parameters such as degradation medium, pH, and time. The hydrolysis of polyester monolayers strongly depended on both the degradation medium used to control subphase pH and the concentration of active ions. Under the conditions studied here, polymer monolayers showed faster hydrolysis when they were exposed to a basic subphase rather than that of acidic or neutral subphase. The basic (pH = 10) hydrolysis of [poly(l-lactide)/polycaprolactone](l-PLA/PCL 1/1 by mole) blend was faster than that of each homopolymer at the initial stage. This result is explained by increasing numbers of base attack sites per unit area owing to the very slow hydrolysis of PCL, a dilution effect on the concentration of l-PLA monolayers. Conversely the hydrolytic behavior of l-lactide-co-caprolactone (1/1 by mole) was similar to that of PCL even though the chemical compositions of the blend and the copolymer are very similar to each other. The resistance of the copolymer to hydrolysis might be attributed to the hydrophobicity and the steric hindrance of caprolactone unit in the copolymer.

• Research Organization: State Univ. of New York, Buffalo, NY (US)
• OSTI ID: 20075524
• Journal Information: Langmuir, Journal Name: Langmuir Journal Issue: 7 Vol. 16; ISSN LANGD5; ISSN 0743-7463
• Country of Publication: United States
• Language: English

Related Subjects

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION
36 MATERIALS SCIENCE
BIOCHEMICAL REACTION KINETICS
BIODEGRADATION
COPOLYMERS
FILMS
HYDROLYSIS
POLYESTERS