Thermal properties and crystallization behaviour of blends of poly(ε-caprolactone) with chitin and chitosan

Blend films of poly(epsilon-caprolactone) (PCL) with chitin and chitosan were prepared as completely biodegradable polyester/polysaccharide composites. Differential scanning calorimetry and Fourier-transform infrared (FTIR) spectroscopy revealed that the crystallization of PCL, which had been suppressed by blending with chitin and chitosan, progressed with the elapse of time after film preparation. The suppression of crystallization of PCL by blending with polysaccharides was also observed by solid-state C-13 NMR spectroscopy. Furthermore, FTIR spectra indicated that the extent of hydrogen bonding between PCL and polysaccharides, which suppressed the crystallization of PCL, decreased with elapse of time after film preparation. Wide-angle X-ray diffraction indicated that the polysaccharides affected the crystallization of PCL and slightly deformed its crystalline lattice. (C) 2003 Society of Chemical Industry.