Unlike polystyrene, a type of polymer normally used to produce plastic and foam which is hard to dissolve, this new product leaves nothing behind in the environment.

The Mtec team chose to use a local agricultural product, tapioca starch, to develop the new bio-degradable loose-fill foam. "As cassava root is one of the country's main agricultural products, we think we should use it for this project as it's a kind of material that we can easily find, and importantly, it does no harm to the environment," said the researcher Piyawit Koombhongse.

The team researched a way to produce bio-degradable loose-fill foam from tapioca using a conventional extruder, the machine that is now used to produce foam or plastic from polystyrene.

The challenge, Piyawat said, was to make a key material from tapioca starch which had properties so similar to polystyrene that it could be extruded through conventional processes. "As tapioca cannot flow as well as polystyrene, especially in the extrusion process, we had to give the material better properties," he said.

To improve the properties of tapioca, the team used poly-vynil alcohol, which can also be degradable, as a binder to give the tapioca starch better flowing properties. Having conducted research for six months, the team has come up with a bio-degradable loose-fill foam which has resilience of 50 per cent. Piyawat said when it came to practical applications, higher resilience was required. The team aims to produce tapioca-based loose-fill foam with at least 70-per-cent resilience.

The team expects that the first prototype of ready-to-use bio-degradable loose-fill foam will come out within a year.

The researcher added that since the foam was made from cassava root powder, it more readily absorbs humidity, so when it comes into real use, it still has limitations. "People can only use it in some products, for example, export flowers. It's really not suitable for use in products like electronics," he said.

Tapioca starch is one of the choices as an ingredient in bio-degradable plastic. In other countries there are research projects to develop similar material from wheat and corn. The researcher said even though the raw material was different, all projects had a common goal: "We want to reduce the use of plastic-based foam, which is slow to degrade, and harms the environment."

pongpen@nationgroup.com

Pongpen Sutharoj

The Nation