Poly(epsilon-caprolactone)/chitin and poly(epsilon-caprolactone)/chitosan blend films with compositional gradients: fabrication and their biodegradability.
Poly(epsilon-caprolactone) (PCL)/chitin and PCL/chitosan blend films with compositional gradients were successfully fabricated by a dissolution/diffusion method; that is, repeatedly pouring the PCL/chitin (or PCL/chitosan) blend solutions, with variable composition, onto polysaccharide layers. The compositional gradient structure in the resulting films was characterized by polarized optic microscopy, ATR-FT-IR and trans-FT-IR microscopic spectroscopy. Enzymatic degradability of the PCL/chitin and PCL/chitosan blend films with compositional gradients in the presence of lysozyme was compared with those of homogeneous films and two-layer films. It was found that the degradation rate of PCL/chitin blend films with a compositional gradient was far lower than that of the neat chitin film, whereas the degradation rate of PCL/chitosan blend films with a compositional gradient was close to that of the neat chitosan film. The suppression of the chitosan crystallization, which accelerates the enzymatic degradation, at the surface of PCL/chitosan films with a compositional gradient was much more severe than that for PCL/chitin films with a compositional gradient.
Department of Biomolecular Engineering, Tokyo Institute of Technology, Midori-ku, Yokohama 226-8501, Japan.
Tomonori
T
Honma
Li
L
Zhao
Naoki
N
Asakawa
Yoshio
Y
Inoue
D001673:Biodegradation, Environmental; D002208:Caproates / Q000737:chemistry*; D002686:Chitin / Q000737:chemistry*; D048271:Chitosan / Q000737:chemistry*; D007783:Lactones / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D008859:Microscopy, Polarization; D011091:Polyesters / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D014961:X-Ray Diffraction
D002208:Caproates; D007783:Lactones; D011091:Polyesters; D002686:Chitin; C121056:caprolactone; D048271:Chitosan