Role of Polymers in Packaging: Ensuring Sustainability for the Future 

Blog by Hunaid Nulwala, PhD 

Packaging materials have become essential to our daily lives, from plastic bags at the grocery store to tetra packs holding our favorite drinks. The development of polymers has revolutionized packaging materials, making it possible for food to have a longer shelf life and enabling us to handle and store necessary and unnecessary items efficiently. Polymers have also led to the creation of numerous products that have transformed our world, and imagining where we would be without them is difficult. 

Polymers have numerous advantages compared to other packaging materials. They have exceptional barrier properties to water and oxygen, which are crucial in preserving perishable items like food. Moreover, plastics are transparent, enabling us to see the contents of the package. They are versatile as they can be colored and printed on. The lightness of plastics makes them suitable for all packaging purposes, including shipping and storage. The advent of plastics has significantly revolutionized various industries worldwide. 

Throughout history, packaging materials have been an essential component of human society. From the early days of woven baskets and earthenware pots to the industrial revolution’s development of tin cans, the need for packaging has always existed. However, the packaging industry underwent a significant transformation in the mid-20th century by introducing synthetic polymers, which have become a vital component of modern-day packaging. These versatile materials have revolutionized the industry, providing unparalleled strength, durability, and flexibility to support the needs of an ever-changing world. Today, synthetic polymers continue to play an indispensable role in packaging, enabling us to transport and store goods safely and efficiently. However, they lack polymer sustainability. 

I remember vividly from childhood when I was around 4-5 years old, standing in a classic 1978- Honda 50 motorcycle basket to get milk from the Nagori milk shop in Karachi, Pakistan. My siblings would sometimes join me in the basket, where there was a stainless-steel canister to hold the milk in this “bring milk home” joy ride. It was a daily chore for my dad to get milk. As soon as the milk arrived, my mom would boil it right away, and the cream would rise above the milk (something that doesn’t happen in pasteurized milk), and we would eat it with honey and parathas. However, plastic bags and tetra packs took over by the late 20th century, and my early morning trips to the milk shop became just a memory. 

Image of Honda Motor Bike

Plastic bottles made it extremely easy and convenient for the dairy industry to deliver milk to every household. It curbed spoilage, simplified the supply chain, and brought the product to consumers in a way that was never possible. The famous line from the movie “The Graduate,” “Plastics” certainly rang true.  

Despite their numerous advantages, plastic polymers present significant environmental challenges. Plastic waste is a major problem worldwide, and much of it ends up in the oceans and landfills, where it can take hundreds of years to decompose. This has led to a growing movement towards more sustainable packaging solutions, such as recycling, upcycling, and biodegradable and compostable materials. As we progress, we must think beyond convenience and focus on sustainability. From an application perspective, an item used in agriculture (such as ag films) can become a part of the soil. Plastics used in shampoos and personal hygiene should be targeted to be upcycled into higher-value components, such as automotive parts and durable products. 

The good news is that sustainable packaging is seeing many exciting innovations that offer hope for the future. Some companies now use bioplastics made from renewable resources, such as cornstarch, which can be composted after use. Others are utilizing plant-based materials like mushrooms or seaweed to create eco-friendly packaging options. Additionally, advanced recycling (upcycling) methods are being developed to generate higher-value products. It is essential to consider the end-use application perspective, and we need to develop innovations specifically for food packaging made entirely from starch and starch-based polymers that can be easily segregated and composted. We should also look into creating 100% edible food packaging, which can become part of the environment even when thrown away. On the recycling side, we need to use computational science, artificial intelligence, and chemical intuition to make more informed decisions about the types of polymers used in future products to make component recycling more accessible. 

As individuals, we hold the power to promote sustainability by demanding eco-friendly packaging and supporting companies that prioritize sustainability. We can also urge legislators to pass laws that impose carbon taxes and prioritize environmental values, especially on products that are difficult to recycle or decompose. Additionally, researchers and scientists can contribute to sustainability efforts by developing innovative materials and processes for sustainable packaging. Making small changes in our daily lives, such as using reusable bags and containers, can also significantly reduce our environmental impact. By taking these steps, we can all play a vital role in ensuring a sustainable future. 

It is imperative that we work together to maintain the advantageous contributions of polymers and packaging toward our societal and personal advancements. However, we must also guarantee that we do so in a sustainable manner that ensures the prosperity and well-being of future generations.