DOI: 10.1094/CC-82-0105 |  VIEW ARTICLE

Melt-Intercalated Starch Acetate Nanocomposite Foams as Affected by Type of Organoclay (1).

Yixiang Xu (2), Jiahua Zhou (3), and Milford A. Hanna (2,4). (1) Journal Series No. 14649, Agricultural Research Division, Institute of Agriculture and Natural Resources, University of Nebraska-Lincoln. This study was conducted at the Industrial Agricultural Products Center, University of Nebraska, Lincoln, NE. (2) Industrial Agricultural Products Center and Department of Food Science & Technology, University of Nebraska, Lincoln, NE 68583-0730. (3) Industrial Agricultural Products Center, University of Nebraska, Lincoln, NE 68583-0730. (4) Corresponding author. Phone: +1-402-472-1634. Fax: +1-402-472-6338. E-mail: <mhanna1@unl.edu> Cereal Chem. 82(1):105-110. Accepted August 27, 2004. Copyright 2005 American Association of Cereal Chemists, Inc.

Starch acetate nanocomposite foams with four organoclays (Cloisite 30B, 10A, 25A, and 20A) were prepared by melt-intercalation methods. The structural properties, thermal behaviors, and mechanical properties were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), differential scanning calorimetry (DSC), thermogravimetry analyses (TGA), and Instron universal testing machine. XRD results indicated that the intercalation of starch acetate into the nanoclay layers occurred for all four clays. The extent of intercalation depended on the type of organoclay and was exhibited in the sequence of Cloisite 30B >10A >25A >20A. SEM results indicated a decrease in cell size in the starch acetate foam matrix with the addition of nanoclay. Glass transition temperature (T(g)) and onset temperatures of thermal degradation increased with the addition of organoclay into the starch acetate matrix. The incorporation of organoclays decreased significantly the compressibilities of starch acetate nanocomposites and did not substantially affect their spring indices.