The increasing rate of environmental pollutions caused by synthetic polymers has attracted attention of the packaging industries to biodegradable polymers famous as bio-polymers.
However, some drawbacks bound to bio-polymer films such as their weaker mechanical properties and higher hydrophilic tendencies have hindered their deployment. As a result, Hadi Almasi, one of the researchers at the University of Tabriz, conducted a research to improve mechanical thermal and preservative (against moisture) properties of starch films.
"In this research, three techniques have been applied simultaneously to improve the properties of starch films," Almasi explained to the Iran Nanotechnology Initiative Council, adding, "The results of this research can be helpful in the production of biodegradable plastics. Such plastics are more beneficial than synthetic plastics in food packaging industries."
Three compounds, namely, citric acid, carboxymethyl cellulose and nanoclay were used to improve the performance of the mentioned starch films. In the first step, the effect of citric acid concentration as cross-linking agent was studied.
After determination of the optimal concentration of citric acid, carboxymethyl cellulose was added. Finally, the concentrations of the former compounds were held constant in order to investigate the effect of nanoclay concentration.
It is notable that all the described steps are practically applicable in polymer production companies and so far, four companies in Iran have started the commercial production of biodegradable disposable products.