Mechanical and Thermal Properties of Self-Assembled Kaolin-Doped Starch-Based Environment-Friendly Nanocomposite Films

Environment-friendly advanced materials are promising candidates for the engineering of nanoscience and nanotechnology. Here, starch–kaolin self-assembled nanocomposite films were prepared using potato starch and an indigenous layered material, kaolin. The films consist of kaolin and the matrix, which were prepared by the disruption and plasticization of starch granules with water and glycerol. Self-assembled nanocomposite films with 0%, 5%, 10%, 15%, and 20% w/w of kaolin were fabricated by casting and evaporating the mixture from homogeneous aqueous suspension at 95 °C. The thickness of the film—about 200 μm—was controlled by a predesigned glass frame. The resulting films were conditioned before testing, and the effect of accelerated aging in a moist atmosphere was investigated. The films were characterized using attenuated total reflection infrared (ATR-IR) spectroscopy for the interaction of moieties via function groups, X-ray diffraction (XRD) for crystallinity change, universal testing machine (UTM) for tensile strength Young’s modulus and elongation at break investigation. The thermal stability of the films using thermogravimetric analysis (TGA) and the effect of temperature on contraction behaviors using thermal mechanical analysis (TMA) were carried out. The distribution of kaolin into the matrix and morphology of the self-assembled nanocomposite films were observed from scanning electron microscopy (SEM) images. Developed nanocomposite materials from an indigenous source would play a vital role in the field of food packaging industries in Bangladesh.

Characterization of Nanocomposites by Thermal Analysis

In materials research, the development of polymer nanocomposites (PN) is rapidly emerging as a multidisciplinary research field with results that could broaden the applications of polymers to many different industries. PN are polymer matrices (thermoplastics, thermosets or elastomers) that have been reinforced with small quantities of nano-sized particles, preferably characterized by high aspect ratios, such as layered silicates and carbon nanotubes. Thermal analysis (TA) is a useful tool to investigate a wide variety of properties of polymers and it can be also applied to PN in order to gain further insight into their structure. This review illustrates the versatile applications of TA methods in the emerging field of polymer nanomaterial research, presenting some examples of applications of differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), dynamic mechanical thermal analysis (DMTA) and thermal mechanical analysis (TMA) for the characterization of nanocomposite materials.