Bio-based thin-film structures to tackle the growing menace of plastics

The world is turning into a global village and consequently, food products from around the world are becoming ubiquitous in the store where you buy your grocery every week. Have you ever wondered what keeps these products fresh and delicious? The answer lies in the product packaging. A package’s importance is often neglected but a lot of science goes into developing that fancy trivial package that often charms you into making buying decisions.

In today’s world, most of the food packaging utilizes petroleum-derived plastics in some form. Usually, the plastic is visible in the package and if not, it might lie as a thin layer under the top layers made from materials like paperboard and metal foils. Due to the rampant use of petroleum-derived plastics in packaging, our environment lies in a grave danger. The amount of plastics being produced for packaging purpose was approximately 161 million tons in 2017 and the amount of plastic waste entering the planet’s oceans annually worldwide was estimated to be 8 million tons. These figures, already gargantuan, are expected to rise rapidly if immediate measures are not taken. We cannot turn a blind eye to the menace of plastics in packaging anymore. We must look for bio-based solutions which are produced, consumed and recycled responsibly.

What does it take to get rid of plastics?

If it were so straightforward to replace plastics with some other biodegradable material, giving the same performance as plastics, it would have been done already. Current challenges in replacing plastics are:

• Common packaging plastics like PE, PP, PS, etc. are extremely cheap.
• The processing technologies for plastics such as, extrusion and injection moulding, are highly developed. Replacing a high-end and mature industrial technology is difficult.
• We don’t have materials that can match or outperform plastics in the properties required by the packaging industry. Such properties include barrier functions like moisture, oil and gas barrier and the unique strength and flexibility offered by plastics.

Hence, the quest to find a material which can offer the demanded properties is on, and nanocellulose has been identified as a candidate material.

What is nanocellulose?

Nanocellulose is obtained by breaking down cellulose fibers (from wood or plants) to the nanoscale size through mechanical and/or chemical treatment. This nanomaterial possess excellent film-forming properties and is non-toxic and 100% biodegradable. Nanocellulose films, even as thin as human hair, exhibit excellent barrier against gas and grease, are strong, flexible, and transparent and hence, have been the center of attention of researchers around the world for the last decade. The production of such films in high-speed industrial processes has been an obstacle to commercialization and my research focuses on that.

But…..You don’t need superpowers to save the planet!

While nanocellulose-based packaging would still take some time to enter the grocery store, we need to play our small part in protecting the environment. Every individual must take responsibility for the waste they produce in everyday life and aim for as proper recycling as possible. This requires alterations in our attitude and habits but we must realize that resources on our planet are limited and we need to live in harmony with nature. We shouldn’t wait for a magical technology to do it for us, change comes from within and we must bring about this change.

Further reading:

1. Fast facts about plastic pollution

2. Continuous roll-to-roll coating of cellulose nanocrystals onto paperboard

 Aayush Kumar Jaiswal is a master’s degree student at the Department of Chemical Engineering, Åbo Akademi University. His research deals with development of technologies enabling the production of thin-film structures from wood-based materials. He received a grant from Tekniikan edistämissäätiö in 2018.