Kinetics and Time−Temperature Equivalence of Polymer Degradation

We studied the hydrolysis kinetics of amorphous polylactide. It was found the hydrolysis rate had a slow-to-fast transition at a certain molecular weight (M n ). This transition was not correlated with the mass loss and water uptake of samples, nor the pH values of testing media. We speculated that...

Full description

Saved in:
Bibliographic Details
Published in:Biomacromolecules 2007-07, Vol.8 (7), p.2301-2310
Main Authors: Lyu, Schley, James, Loy, Brian, Lind, Deanna, Hobot, Christopher, Sparer, Randall, Untereker, Darrel
Format: Article
Language:English
Subjects:
Applied sciences
Chemical reactions and properties
Degradation
Exact sciences and technology
Hydrogen-Ion Concentration
Hydrolysis
Kinetics
Organic polymers
Physicochemistry of polymers
Polymers - chemistry
Temperature
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:We studied the hydrolysis kinetics of amorphous polylactide. It was found the hydrolysis rate had a slow-to-fast transition at a certain molecular weight (M n ). This transition was not correlated with the mass loss and water uptake of samples, nor the pH values of testing media. We speculated that this transition was due to the slow diffusion of polymer chain ends. The chain ends did not significantly promote the hydrolysis of samples until their concentrations (∼1/M n ) reached a critical value. The degradation tests were also conducted over a temperature range from 37 to 90 °C. A time−temperature equivalent relationship of degradation processes was established and a master curve spanning a time range equivalent to 3−5 years at 37 °C was constructed. This master curve can be used to predict polymer degradation processes based on accelerated tests. The functional time and disappearance time of degradable polymers were also discussed.
ISSN:1525-7797
1526-4602
DOI:10.1021/bm070313n