Biocomposites obtaining with natural fillers and potato starch polymer

MORÁN JUAN; MANFREDI LILIANA; CYRAS VIVIANA; VAZQUEZ ANALÍA

San Sebastián. España

Congreso; V International Conference on Science and Technology of Composite Materials - 8° Congreso Nacional de Materiales Compuestos; 2009

Asociación Española de Materiales Compuestos

Starch is a biodegradable polymer produced in abundance from many renewable resources. As a consequence it is easily available and very cheap. However, it is necessary to reduce their water absorption, as well as improve their mechanical properties. Gelatinized potato starch in the presence of water and glycerol was used as references material. In order to decrease their hydrophibicity starch was acetylated (with acetic acid and anhydride), maleated (with maleic anhydride) and esterified with octanoyl chloride. Films were prepared from potato starch and montmorillonite. The clay dispersion in the films was analyzed by X-ray diffraction (XRD). It was observed that the 001 diffraction peak of clay was shift to lower angles in the nanocomposites patterns providing strong evidence that the clay nanolayers formed an intercalated structure but not complete exfoliation. The water absorbed by the nanocomposites measured in an environment with a 75% of constant relative humidity was reduced by the addition of montmorillonite to the starch. The micro-tensile test was performed on the nanocomposite films showing significant improvement in the Young modulus up to 500% for the nanocomposite containing 5 wt% of clay.