Researchers have developed eco-friendly paper straws that are 100% biodegradable, perform better than conventional paper straws and can be easily mass-produced. The paper straws currently available are not made entirely of paper. Straws made of 100% paper get too wet when in contact with liquids and cannot function as straws.
Accordingly, their surfaces must be coated. Scientists at the Korea Research Institute of Chemical Technology synthesized a well-known biodegradable plastic, polybutylene succinate (PBS), by adding a small amount of cellulose nanocrystals to form a coating material. The added cellulose nanocrystals are the same material as the main component of the paper, allowing the biodegradable plastic to adhere firmly to the paper surface during the coating process.
Made of paper and biodegradable plastic
The new paper straws do not easily become wet or cause bubbles to form in carbonated drinks because the coating material evenly and strongly covers the surface of the straws, the researchers said. Also, the cover material is made of paper and biodegradable plastic and therefore completely decomposes and degrades, they said.
“Converting the plastic straw we often use to a paper straw will not have an immediate impact on our environment, but the difference will be profound over time,” said lead researcher Oh Dongyeop. “If we gradually switch from using convenient disposable plastic products to a variety of eco-friendly products, our future environment will be much safer than what we fear now,” Dongyeop said.
Research published in the journal Advanced Science found that these eco-friendly paper straws maintain their physical integrity in both cold and hot drinks. The team also found that the straws did not become wet when used to mix various beverages such as water, tea, carbonated beverages, milk and other lipid-containing beverages, or when exposed to liquids for long periods of time.
The researchers compared the degree of wetting of the new paper straws and regular paper straws. A conventional paper straw was severely bent when the straw was immersed in cold water at 5 degrees Celsius for one minute while a weight of approximately 25 grams was suspended, they said. In contrast, the new paper straw did not bend as much even when weighing more than 50 grams under the same conditions.
The new straws also decompose well in the ocean. In general, paper or plastic decomposes much more slowly in the ocean than in land due to the ocean’s low temperature and high salinity, which inhibits microbial growth.
