Preparation and characterization of starch/enteromorpha/nano-clay hybrid composites

Environmentally friendly and biodegradable hybrid composites of starch/enteromorpha/nano-clay were developed. Enteromorpha was used as cheaper filler since it is a waste from marine pollution, while nano-clay acted as a reinforcing agent. The microstructures and performance of these composites were investigated by SEM, DMA, XRD, TGA and tensile testing. Enteromorpha has a hollow tubular thallus structure with very weak mechanical properties, so it is not expected to have the ability to reinforce the starch matrix even though they have very a good interface. However, the granulated fine particles of enteromorpha can mix well with the starch matrix and reduce weak points. Furthermore, the delaminated clay by water and ultrasonic treatment reinforced the mechanical properties of the starch-based materials. The results showed that the hybrid composite containing up to 40% enteromorpha reinforced with nano-clay still has similar or even slightly better mechanical properties compared with pure starch-based materials. Since all components are hydrophilic natural materials, the interfaces between them are very good, and the composites are environmentally friendly and biodegradable.