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Updated: Aug 7, 2025

Film Extrusion of Crambe abyssinica/Wheat Gluten Blends
Published on: January 17, 2017
Effects of primary, secondary and tertiary structures on functional properties of thermoplastic starch biopolymer
Na Yang1, Feixue Zou1, Haiteng Tao1
1State Key Laboratory of Biobased Material and Green Papermaking, School of Food Sciences and Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan, China.
Abstract:
To better understand the correlation between structure and properties in thermoplastic starch biopolymer blend films, the effects of amylose content, chain length distribution of amylopectin and molecular orientation of thermoplastic sweet potato starch (TSPS) and thermoplastic pea starch (TPES) on microstructure and functional properties of thermoplastic starch biopolymer blend films were studied. After thermoplastic extrusion, the amylose contents of TSPS and TPES decreased by 16.10 % and 13.13 %, respectively. The proportion of the chains with the degree of polymerization between 9 and 24 of amylopectin in TSPS and TPES increased from 67.61 % to 69.50 %, and from 69.51 % to 71.06 %, respectively. As a result, the degree of crystallinity and molecular orientation of TSPS and TPES films increased as compared to sweet potato starch and pea starch films. The thermoplastic starch biopolymer blend films possessed a more homogeneous and compacter network. The tensile strength and water resistance of thermoplastic starch biopolymer blend films increased significantly, whereas thickness and elongation at break of thermoplastic starch biopolymer blend films decreased significantly.
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