Characterizations of glycerol plasticized-starch (GPS)/carbon black (CB) membranes prepared by melt extrusion and microwave radiation

As electrically conductive polymer composites, glycerol plasticized-starch (GPS)/carbon black (CB) membranes are respectively prepared by melt extrusion and microwave radiation. Scanning electron microscopy shows that the electrical conductance network of CB is formed in GPS/CB membranes, prepared by microwave radiation (GPS/CB-MR). However, the agglomerates of CB particles are isolated in GPS/CB membranes, prepared by melt extrusion (GPS/CB-ME). Fourier Transform Infrared (FTIR) spectroscopy reveals that CB and GPS matrix can form the interaction in GPS/CB membranes. According to Nicholais-Narkis models, the reinforcing effect of CB is more obvious in GPS/CB-MR membranes than in GPS/CB-ME membranes. GPS/CB-MR membranes exhibit a low electrical percolation threshold of 2.398 vol% CB loading and the conductivity of the membrane containing 4.236 vol% CB reaches 7.08 S/cm, while GPS/CB-ME membranes shows a very low conductivity of 10(-8) S/cm at the high CB content. In addition. GPS/CB-MR membranes have better water vapor barrier than GPS/CB-ME membranes. (C) 2008 Elsevier Ltd. All rights reserved.