Abstract
In order to prepare a porous three-dimensional (3-D) structure in biodegradable polyester materials we have conducted the enzymatic degradation of a poly(L-lactide) (PLLA)-based nano-composite foam, having a nanocellular structure, using proteinase-K as a degrading agent at 37°C. The surface and cross sectional morphologies of the foam recovered after enzymatic hydrolysis for different intervals were investigated by using a scanning electron microscope. The nanocellular material took up a large amount of water, which led to the swelling of the foam due to the large surface area inside the nanocelluar structure, and facilitated the enzymatic degradation of the PLLA matrix as compared with the bulk (pre-foamed) sample. Consequently, we have successfully prepared a porous 3-D structure as a remaining scaffold in the core part of the nano-composite foam, reflecting the spherulites of the crystallized PLLA.
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