Plastic which is biodegradable

Both are inexpensive and readily available enzymes. The quick degradation works well with municipal composting, which typically takes 60 to 90 days to turn food and plant waste into usable compost.

Industrial composting at high temperatures takes less time, but the modified polyesters also break down faster at these temperatures.

Graduate student Ivan Jayapurna with a sample film of PCL polycaprolactone , a new, biodegradable polyester plastic. PCL with embedded enzymes has mechanical properties very similar to those of low-density polyethylene, making it a promising future alternative to non-biodegradable plastics.

Xu suspects that higher temperatures make the enshrouded enzyme move around more, allowing it to more quickly find the end of a polymer chain and chew it up and then move on to the next chain. The RHP-wrapped enzymes also tend to bind near the ends of polymer chains, keeping the enzymes near their targets. The modified polyesters do not degrade at lower temperatures or during brief periods of dampness, she said. A polyester shirt made with this process would withstand sweat and washing at moderate temperatures, for example.

Soaking in water for three months at room temperature did not cause the plastic to degrade. We used warm tap water. Just warm it up to the right temperature, then put it in, and we see in a few days it disappears. Xu is developing RHP-wrapped enzymes that can degrade other types of polyester plastic, but she also is modifying the RHPs so that the degradation can be programmed to stop at a specified point and not completely destroy the material.

This might be useful if the plastic were to be remelted and turned into new plastic. A film of PLA polylactic acid plastic embedded with an enzyme to make it biodegrade quickly in regular compost.

Xu said that programmed degradation could be the key to recycling many objects. We are taking things from the earth at a faster rate than we can return them.

Professor Ting Xu, who contributed to the research, explains how this new material is made with built-in enzymes, just like human digestion. The enzymes interact with synthetic polymers a generic class of plastics in a chewing process, turning them into tiny non-toxic molecules, nanoscopic to the eye and harmless to the soil. The research team based their observation on biodegradable polyesters a sub class of plastics , such as polycaprolactone PLC and polylactic acid PLA.

The whole chewing-thanks-to-the-built-in-enzyme process was only possible as the team experimented under hot conditions. PLC just took two days to break down under 40 degrees Celsius, and the PLA completely disappeared within six days when the material was put under 50 degrees Celsius.

Read More: Plastic bag recycling at home. Are Plastics Biodegradable? Section About Plastics. Professor Plastics Read Bio. OK, a little more science … To biodegrade, organic materials require air, water, light or a combination of these elements so microorganisms can do their job.

Read More: Plastic bag recycling at home So … biodegradability of plastics depends largely on the type of plastic and where it ends up.

Today there are only a handful of large composting facilities in the U. Biodegradable plastics must be separated from plastics that are being recycled another future lesson topic.