Vol. 24, No. 5
from Pure and Applied Chemistry
on Biodegradable Poly[hexano-6- lactone] Fibers. Part 3. Enzymatic Degradation
in Vitro (IUPAC Technical Report)
Hayashi, K. Nakayama, M. Mochizuki, and T. Masuda
Pure and Applied
Chemistry, Vol. 74, No. 5, pp. 869- 880 (2002)
describes how poly(hexano-6-lactone) (PCL) fibers were enzymatically
degraded by a hydrolase in vitro. The extent of degradation of PCL fibers
was examined by weight loss, mechanical properties loss such as tensile
strength and ultimate elongation decreases, and visual observations
by scanning electron microscopy. The in vitro degradation of PCL fibers
was carried out using a lipoprotein lipase (Lipase-PS) as a hydrolase.
The kinetic study on the weight loss of PCL fiber accompanying the enzymatic
degradation suggested that the degradation of PCL fibers gradually takes
place from the surface, not bulk degradation. The rate of degradation
was found to depend on draw ratio and crystallinity of the PCL fibers.
The strength loss of PCL fibers in the course of degradation took place
faster than the weight loss of PCL fibers. Sonic velocity measurements
as well as dynamic mechanical properties of PCL fibers were also examined
as a function of weight loss of sample fibers with Lipase-PS treatments.
It was shown that sonic velocity and value of loss tangent d changed
steeply for undrawn PCL fiber in the first step with enzymatic digestion.