Journal of Bioresources and Bioproducts. 2018, 3(3) 107-111
Peer-Reviewed
gelatin/MFC composite film still kept a much higher transmittance in general, which also reflected the good compatibility between gelatin and MFC.
strength (12.32 MPa). However, the gelatin/MFC composite films showed a decreasing elongation at break, which can be attributed to the decrease of film-forming solution matrix mobility as the MFC content increased. 22 In general, the composite films had more improved mechanical properties than neat gelatin films.
Fig. 2. Tensile strength (TS) and elongation at break (EAB) curves of gelatin/MFC composite films with various MFC mass concentrations: 0.2%,0.4%, 0.6%, 0.8%, 1.0%. 3.3. Thermogravimetric and heat shrinkage analysis Generally, the thermogravimetric curve of the biopolymer-based film has three stages: the loss of physically absorbed water, structured water and decomposition of biomolecules. 23 From Fig. 3a we can observe that the first stage of weight loss was about 150 °C, which mainly contained free water and volatile substance. However, gelatin/MFC composite film was more stable than pure gelatin film at about 270 °C (weight loss of less than 10%). Moreover, the Maximum weight loss of pure gelatin film and gelatin/MFC was about 500 °C and 600 °C, respectively. From heat shrinkage curves of gelatin/MFC composite films (Fig. 3b), the heat shrinkage of composite film decreased by adding MFC of various mass concentration, which was about 0.67%. All in all, MFC promoted the stability of gelatin film. 3.4. Optical properties The light transmittance of pure gelatin films and gelatin/MFC composite films was illustrated in Fig.4. At the center of the visible light 600 nm, which showed some differences between pure gelatin (86.5%) and five gelatin/MFC composite films with the date of 82.9%, 83.4%, 82.2%, 83.1% and 78.2%, respectively. The decrease in light transmittance was mainly due to the phenomenon of reflection or scattering at the interface between gelatin and MFC, 24 which might be confirmed by scanning electron microscopy (SEM). However, the
Fig. 3. TG and heat shrinkage curves of pure gelatin film and gelatin/MFC composite films with various MFC mass concentrations: 0.0 %, 0.2 %,0.4 %, 0.6 %, 0.8 %, 1.0 %.
Fig. 4. Light transmittance curves of neat gelatin films and gelatin/MFC composite films with various MFC mass concentrations: 0.0% (a), 0.2% (b), 0.4% (c), 0.6% (d), 0.8% (e), 1.0% (f). 3.5. Water absorption properties
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