- Tytuł:
- Hydrolytic Degradation of Poly(L-Lactide-co-Glycolide) Studied by Positron Annihilation Lifetime Spectroscopy and Other Techniques
- Autorzy:
-
Pamuła, E.
Dryzek, E.
Dobrzyński, P. - Powiązania:
- https://bibliotekanauki.pl/articles/2047148.pdf
- Data publikacji:
- 2006-11
- Wydawca:
- Polska Akademia Nauk. Instytut Fizyki PAN
- Tematy:
-
82.35.-x
82.35.Lr
78.70.Bj
61.18.Fs
82.56.Ub
83.85.Jn
68.37.Ps - Opis:
- Changes of the poly(L-lactide-co-glycolide) structure as a function of degradation time in phosphate-buffered saline for 7 weeks were investigated by gel permeation chromatography, differential scanning calorimetry, nuclear magnetic resonance ($\text{}^{1}$H NMR), and positron annihilation lifetime spectroscopy. Surface properties as wettability by sessile drop and topography by atomic force microscopy were also characterized. Chain-scission of polyester bonds in hydrolysis reaction causes a quite uniform decrease in molecular weight, and finally results in an increase in semicrystallinity. Molecular composition of the copolymer and water contact angle do not change considerably during degradation time. Atomic force microscopy studies suggest that the copolymer degrades by "in bulk" mechanism. The average size of the molecular-level free volume holes declines considerably after one week of degradation and remains constant till the sixth week of degradation. The free volume fraction decreases as a function of degradation time.
- Źródło:
-
Acta Physica Polonica A; 2006, 110, 5; 631-640
0587-4246
1898-794X - Pojawia się w:
- Acta Physica Polonica A
- Dostawca treści:
- Biblioteka Nauki
Artykuł