title: Self-reinforcement and hydrolytic degradation of amorphous lactic acid based poly(ester-amide), and of its composite with sol-gel derived fibers.
abstract: The self-reinforcing and hydrolytic degradation of an amorphous poly(ester-amide) (PEA) based on lactic acid have been studied and compared with those of poly-L-lactide (PLLA). The studied PEA-rods were self-reinforced (SR) by solid-state die drawing resulting double shear strength. The hydrolytic degradation of PEA was studied during exposure to phosphate buffered saline at pH 7.4 and at 37 degrees C for 18 weeks. The degradation and mechanical properties of PEA were also followed in a self-reinforced composite structure consisting of PEA and sol-gel derived SiO(2)-fibers (SGF, 8 wt %). The hydrolytic degradation of the SR-PEA-rods with and without SG-fibers was significantly faster than that of SR-PLLA-rods. The weight average molecular weight (Mw) of PEA decreased by 90% from the initial Mw during the first 6 weeks in hydrolysis, when the Mw of the PLLA decreased by 10%.
authors.affiliation: Tampere University of Technology, Institute of Biomaterials, P.O. Box 589, FIN-33101 Tampere, Finland.
authors.forename: Anna-Maija
authors.initials: AM
authors.lastname: Haltia
authors.forename: Kimmo
authors.initials: K
authors.lastname: Lähteenkorva
authors.forename: Pertti
authors.initials: P
authors.lastname: Törmälä
authors.forename: Antti
authors.initials: A
authors.lastname: Helminen
authors.forename: Jukka
authors.initials: J
authors.lastname: Tuominen
authors.forename: Jukka
authors.initials: J
authors.lastname: Seppälä
authors.forename: Sinikka
authors.initials: S
authors.lastname: Veittola
authors.forename: Jarno
authors.initials: J
authors.lastname: Ahvenlammi