Mechanical Properties of Porous Polylactide/Chitosan Blend Membranes

Abstract

Porous membranes were fabricated using chitosan and poly(DL‐lactide) or poly(L‐lactide) blends through a combinatorial technique. Well‐controlled porous structures could be achieved by optimizing processing conditions. The ductility and toughness of dry porous membranes were improved by incorporating an increased amount of chitosan, and the physical strength and dimensional stability of hydrated porous membranes were preserved if the components were used in a suitable ratio. Although there were measurable differences in the pore‐size distributions of membranes with the same composition prepared under identical conditions, this showed no effect in their dry states.magnified image

Poly(Lactic Acid) Blends

“…In summary, the addition of PLA helped provide a finer morphology, reduced beading, and increased the average fiber diameter of chitosan/PLA spun fibers. On the other hand, increasing chitosan reduced the tensile strength, Young's modulus, compressive stress, and compressive modulus but enhanced elongation at break of chitosan/PLA porous membranes [252,259]. After immersion in PBS solution (0.2 M, pH 7.4) for 2 h, the hydrated chitosan/PLA porous membrane had lower mechanical properties except for significantly higher elongation at break compared to the dry membranes [252].…”

“…Chitosan is formed by alkaline deacetylation of chitin [252]. It is hydrophilic with a weak basic property and more soluble with higher antimicrobial activity than chitin [250,252].…”

“…It is hydrophilic with a weak basic property and more soluble with higher antimicrobial activity than chitin [250,252]. Considering its biocompatibility, biodegradability, nontoxicity, bioadhesion, chelating and film-forming properties, and its affinity for nerve cells, chitosan is a promising material for biomedical, (active/edible) food packaging, food, and water treatment applications [250,[252][253][254].…”

“…It is hydrophilic with a weak basic property and more soluble with higher antimicrobial activity than chitin [250,252]. Considering its biocompatibility, biodegradability, nontoxicity, bioadhesion, chelating and film-forming properties, and its affinity for nerve cells, chitosan is a promising material for biomedical, (active/edible) food packaging, food, and water treatment applications [250,[252][253][254]. The casting blend films of the blend solutions (i.e., chitosan (80-85% degree of deacetylation (DDA)) dissolved in acetic acid and PLA (M w ¼ 49 kDa) dissolved in chloroform and then blended) containing 10-30% PLA were immiscible (determined from T g 's, FTIR spectra, and tensile moduli) [254].…”

“…For example, melt blending and sodium chloride were used to design the degree and the size of scaffold porosity [257]. The porous membrane scaffolds were prepared by a combination of solvent extraction, liquid-solid separation, and freeze-drying [252,259]. Nerve conduits for peripheral nerve regeneration were fabricated with a mold casting/infrared dehydration technique, whereas micro/nanofibers from electrospinning were used in a native extracellular matrix for tissue engineering [260].…”