Scientists Create Self-Cleaning Bioplastic Inspired by Lotus

This picture shows farmer Nguyen Van Khoa harvesting lotus flowers on a pond in Hanoi. (AFP)
This picture shows farmer Nguyen Van Khoa harvesting lotus flowers on a pond in Hanoi. (AFP)
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Scientists Create Self-Cleaning Bioplastic Inspired by Lotus

This picture shows farmer Nguyen Van Khoa harvesting lotus flowers on a pond in Hanoi. (AFP)
This picture shows farmer Nguyen Van Khoa harvesting lotus flowers on a pond in Hanoi. (AFP)

A research team at the Royal Melbourne Institute of Technology (RMIT) have developed a self-cleaning bioplastic that is eco-friendly and ideal for fresh food and takeaway packaging.

The new plastic is inspired by the nature full of ingeniously designed structures that could inspire researchers striving to develop new high-performance and multifunctional materials, reported the team in their study published March 8 in the journal Science of The Total Environment.

Plastic waste is one of our biggest environmental challenges but the alternative this team developed is both eco-friendly and cost-effective. "We've replicated the phenomenally water-repellent structure of lotus leaves to deliver a unique type of bioplastic that precisely combines both strength and degradability," lead author Mehran Ghasemlou said.

The bioplastic is made from cheap and widely available raw materials -- starch and cellulose -- to keep production costs low and support rapid biodegradability.

The fabrication process does not require complicated equipment and would be simple to upscale to a roll-to-roll production line, Ghasemlou said.

While biodegradable plastics are a growing market, most biodegradable or compostable plastics require industrial processes and high temperatures to break them down.

The new bioplastic does not need industrial intervention to biodegrade, with trials showing it breaks down naturally and quickly in soil. "There are big differences between plant-based materials -- just because something is made from green ingredients doesn't mean it will easily degrade," Ghasemlou said.

"We carefully selected our raw materials for compostability and this is reflected in the results from our soil studies, where we can see our bioplastic rapidly breaks down simply with exposure to the bacteria and bugs in soil. Our ultimate aim is to deliver packaging that could be added to your backyard compost or thrown into a green bin alongside other organic waste, so that food waste can be composted together with the container it came in, to help prevent food contamination of recycling,” he explained.

The researchers inspired their new bioplastic from the always immaculate lotus leaf renowned for having some of the most water-repellent surfaces on earth and are almost impossible to get dirty.

The secret lies in the leaf's surface structure, which is composed of tiny pillars topped with a waxy layer. Any water that lands on the leaf remains a droplet, simply rolling off with the help of gravity or wind. The droplets sweep up dirt as they slide down, keeping the leaf clean.

To make their lotus-inspired material, the RMIT team of science and engineering researchers first synthetically engineered a plastic made of starch and cellulosic nanoparticles. The surface of this bioplastic was imprinted with a pattern that mimics the structure of lotus leaves, then coated with a protective layer of PDMS, a silicon-based organic polymer.

Tests show the bioplastic not only repels liquids and dirt effectively, but also retains its self-cleaning properties after being scratched with abrasives and exposed to heat, acid and ethanol. Corresponding author, Professor Benu Adhikari, said the design overcomes key challenges of starch-based materials.

"Starch is one of the most promising and versatile natural polymers, but it is relatively fragile and highly susceptible to moisture. By mimicking the 'lotus effect', we have delivered a highly effective starch-based biodegradable plastic," Adhikari said.

Ghasemlou is currently working with a bioplastic company, which is evaluating further development of these novel water repellant materials to start the commercial applications of the bioplastic.



US YouTuber Remains in Custody in India after Visiting Restricted Island with Diet Coke Can

FILE – Clouds hang over the North Sentinel Island, in India’s southeastern Andaman and Nicobar Islands, Nov. 14, 2005. (AP Photo/Gautam Singh, File)
FILE – Clouds hang over the North Sentinel Island, in India’s southeastern Andaman and Nicobar Islands, Nov. 14, 2005. (AP Photo/Gautam Singh, File)
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US YouTuber Remains in Custody in India after Visiting Restricted Island with Diet Coke Can

FILE – Clouds hang over the North Sentinel Island, in India’s southeastern Andaman and Nicobar Islands, Nov. 14, 2005. (AP Photo/Gautam Singh, File)
FILE – Clouds hang over the North Sentinel Island, in India’s southeastern Andaman and Nicobar Islands, Nov. 14, 2005. (AP Photo/Gautam Singh, File)

A 24-year-old American YouTuber who was arrested after visiting an off-limits island in the Indian Ocean with hopes of establishing contact with a reclusive tribe was further detained in custody on Thursday.

Mykhailo Viktorovych Polyakov will next appear before a local court in Port Blair -- the capital of India's Andaman and Nicobar Islands -- on April 29, police said.

Polyakov, from Scottsdale, Arizona, was arrested on March 31, two days after he set foot on the restricted territory of North Sentinel Island in a bid to meet people from the reclusive Sentinelese tribe.

“It may be claimed to be an adventure trip, but the fact is that there has been a violation of Indian laws. Outsiders meeting Sentinelese could endanger the tribe’s survival,” said a senior police officer, requesting anonymity as he isn’t authorized to speak about the case under investigation.

Polyakov is suspected of violating Indian laws that carry a possible sentence of up to five years in prison and a fine, The AP news reported.

Visitors are banned from traveling within 3 miles (5 kilometers) of North Sentinel Island, whose population has been isolated from the rest of the world for thousands of years. The inhabitants use spears and bows and arrows to hunt the animals that roam the small, heavily forested island. Deeply suspicious of outsiders, they attack anyone who lands onto their beaches.

In 2018, an American missionary who landed illegally on the beach was killed by North Sentinelese Islanders who apparently shot him with arrows and then buried his body on the beach. In 2006, the Sentinelese had killed two fishermen who had accidentally landed on the shore.

An official from the US consulate visited Polyakov in jail earlier this week. The US embassy in Delhi didn’t immediately respond to a request confirming the visit or any further updates on Polyakov.

Police said Polyakov had conducted detailed research on sea conditions, tides and accessibility to the island before starting his journey. He stayed on the beach for about an hour, blowing a whistle to attract the attention but got no response from the islanders.

The young American had twice attempted to visit the island in the past, and left a can of Diet Coke and a coconut as offering for the tribe this time after he failed to contact the Sentinelese. He shot a video of the island on his camera and collected some sand samples before returning to his boat.

On his return he was spotted by local fishermen, who informed the authorities and Polyakov was arrested in Port Blair, an archipelago nearly 750 miles (1,207 kilometers) east of India’s mainland.