The influence of layered compounds on the properties of starch/layered compound composites

• Published in: Polymer international 2003-06, Vol.52 (6), p.1035-1044
• Main Authors: Wilhelm, Helena-M, Sierakowski, Maria-R, Souza, Gabriel P, Wypych, Fernando
• Format: Article
• Language: English
• Subjects: Applied sciences; Composites; Exact sciences and technology; Forms of application and semi-finished materials; layered compound; Natural polymers; Physicochemistry of polymers; Polymer industry, paints, wood; starch; Starch and polysaccharides; Technology of polymers
• ISSN: 0959-8103; 1097-0126
• DOI: 10.1002/pi.1198

Glycerol‐plasticized starch films were modified by addition of various layered compounds as fillers, two being of natural origin (kaolinite, a neutral mineral clay, and hectorite, a cationic exchanger mineral clay) and two synthetic (layered double hydroxide, LDH, an anionic exchanger, and brucite, having a neutral structure). The effects of the filler type and the plasticizer were analyzed by X‐ray diffraction, dynamic mechanical analysis and thermogravimetry. The storage modulus was higher for kaolinite > brucite > hectorite than for LDH starch composites. However, only the hectorite filler presented a shift of the interplanar basal distance to higher values, which represents the intercalation of glycerol molecules between the clay layers. The glycerol intercalation is minimized in plasticized–oxidized starch films where the oxidized starch chains are preferentially intercalated. Copyright © 2003 Society of Chemical Industry