Effects of cellulose whiskers on properties of soy protein thermoplastics.
Environmentally-friendly SPI/cellulose whisker composites were successfully prepared using a colloidal suspension of cellulose whiskers, to reinforce soy protein isolate (SPI) plastics. The cellulose whiskers, having an average length of 1.2 microm and diameter of 90 nm, respectively, were prepared from cotton linter pulp by hydrolyzing with sulfuric acid aqueous solution. The effects of the whisker content on the morphology and properties of the glycerol-plasticized SPI composites were investigated by scanning electron microscopy, dynamic mechanical thermal analysis, differential scanning calorimetry, ultraviolet-visible spectroscopy, water-resistivity testing and tensile testing. The results indicated that, with the addition of 0 to 30 wt.-% of cellulose whiskers, strong interactions occurred both between the whiskers and between the filler and the SPI matrix, reinforcing the composites and preserving their biodegradability. Both the tensile strength and Young's modulus of the SPI/cellulose whisker composites increased from 5.8 to 8.1 MPa and from 44.7 to 133.2 MPa, respectively, at a relative humidity of 43%, following an increase of the whisker content from 0 to 30 wt.-%. Furthermore, the incorporation of the cellulose whiskers into the SPI matrix led to an improvement in the water resistance for the SPI-based composites.
Wang
Yixiang
Y
Department of Chemistry, Wuhan University, Wuhan 430072, China.
Cao
Xiaodong
X
Zhang
Lina
L
D000596:Amino Acids / Q000737:chemistry; D002152:Calorimetry, Differential Scanning; D002482:Cellulose / Q000737:chemistry* / Q000648:ultrastructure; D002851:Chromatography, High Pressure Liquid; D018625:Microscopy, Atomic Force; D010969:Plastics / Q000737:chemistry*; D030262:Soybean Proteins / Q000737:chemistry* / Q000302:isolation & purification; D013696:Temperature; D013718:Tensile Strength; D013818:Thermogravimetry; D014867:Water / Q000737:chemistry
D000596:Amino Acids; D010969:Plastics; D030262:Soybean Proteins; D014867:Water; D002482:Cellulose