Plastic is a very useful material. They have contributed great benefits to modern society. But the unprecedented amount of plastics produced over the past few decades has caused serious environmental pollution.
Packaging alone was responsible for 46% of 340 million tons of plastic waste generated globally in 2018. Although plastic recycling has increased dramatically in recent years, most plastics in use today are single-use, non-recyclable and non-biodegradable.
The demand for food will double by 2050. This will likely lead to an increase in the amount of food waste and its plastic packaging, putting poor countries under tremendous pressure to manage waste disposal.
To address issues of environmental damage, we need more sustainable materials that we can recycle or biodegrade. There has been an increase in plastics made from plants, but many of them can only be composted using industrial processes, not by people in the home.
right Now researchers At Cambridge University, she found a way to make plastic from abundant, sustainable plant proteins. The film is inspired by spider silk, and works in a similar way to other plastics, but can be composted at home.
types of plastic
Synthetic and non-biodegradable plastics commonly used in food packaging include polyethylene terephthalate (PET), polystyrene (PS), and crystalline polyethylene terephthalate (CPET).
There are some processes applied for the disposal of PET – they are mechanical and Chemical Recycling Techniques – But most plastic around the world It is still sent to landfills. PET can take hundreds of years to degrade and is non-biodegradable. This means that it can continue to pollute the ecosystem for many years.
Making plastic takes a lot of energy. And then, when plastics are discarded, they cause environmental damage, including global warming, greenhouse gas emissions and harm to marine life.
On the other hand, there are some biodegradable materials vegetable plastic, such as polylactic acid (PLA), polybutylene succinate (PBS), polycaprolactone (PCL), and polyhydroxyalkanotes (PHAs), which are more environmentally friendly than non-renewable polymers.
PLA polymers are produced from renewable sources and have the advantage of being Recyclable and compostable. This makes PLA a much more environmentally friendly material than PET, PS and CPET. However, its durability and long-term stability are inferior to its synthetic counterparts.
The new research investigated the possibility of using a biodegradable, renewable polymer, such as soy protein, to make a new material that could be an alternative to other plant-based plastics.
The researchers created plant-based plastics and added nanoparticles – particles smaller than a millionth of a meter. This means that they can control the structure of the material to create flexible membranes, using a substance that resembles spider silk at the molecular level. They called it “vegetable spider silk.”
The team used various techniques, including scanning electron microscopy and transmission electron microscopy to study the film’s structure.
They analyzed important properties, such as barrier properties and moisture absorption. They found that the nanoparticles helped to significantly increase various properties – strength, durability and long-term stability -.
A significant amount of energy can be saved by making a plastic with a more environmentally friendly manufacturing process, and made from sustainable materials themselves. This is one of the most exciting parts of this study.
This new material could help solve some of the problems plastic pollution has caused to the environment – by introducing a material from a renewable source with improved properties suitable for many engineering applications, including packaging.
The study could help expand the production of sustainable packaging materials, using natural resources and consuming less energy, while reducing the amount of plastic that goes to landfill.
top image: Shutterstock / Olga Meltsova