Thermoplastic Starch−Waxy Maize Starch Nanocrystals Nanocomposites

• Published in: Biomacromolecules Vol. 7; no. 2; pp. 531 - 539
• Main Authors: Angellier, Hélène, Molina-Boisseau, Sonia, Dole, Patrice, Dufresne, Alain
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 01.02.2006
• Subjects: Applied sciences; Chemical Sciences; Composites; Crystallization; Exact sciences and technology; Forms of application and semi-finished materials; Glycerol - chemistry; Hydrogen Bonding; Hydrolysis; Material chemistry; Nanostructures - chemistry; Polymer industry, paints, wood; Starch - chemistry; Technology of polymers; Temperature; X-Ray Diffraction; Zea mays - chemistry; Plasticizer; Dynamic mechanical properties; Ageing; Concentration effect; Glycerol; Mechanical properties; Oside polymer; Nanocomposite; Experimental study; Corn starch; Nanocrystal
• ISSN: 1525-7797; 1526-4602
• DOI: 10.1021/bm050797s

Waxy maize starch nanocrystals obtained by hydrolysis of native granules were used as a reinforcing agent in a thermoplastic waxy maize starch matrix plasticized with glycerol. Compared to our previous studies on starch nanocrystals reinforced natural rubber (NR) [Macromolecules 2005, 38, 3783; 2005, 38, 9161], the present system presents two particularities:  (i) thermoplastic starch is a polar matrix, contrarily to NR, and (ii) the chemical structures of the matrix and the filler are similar. The influence of the glycerol content, filler content, and aging on the reinforcing properties of waxy maize starch nanocrystals (tensile tests, DMA) and crystalline structure (X-ray diffraction) of materials were studied. It was shown that the reinforcing effect of starch nanocrystals can be attributed to strong filler/filler and filler/matrix interactions due to the establishment of hydrogen bonding. The presence of starch nanocrystals leads to a slowing down of the recrystallization of the matrix during aging in humid atmosphere.