Polystyrene (PS) is a highly popular packaging polymer, not just in South Africa but around the world, too. It is used to manufacture a variety of products, from fruit punnets and supermarket food trays to disposable coffee cups and plastic cutlery. PS is fairly easy to recycle and has many beneficial uses – including the manufacture of seedling trays, picture frames and even lightweight building blocks for the construction industry.
Most of the plastics used for packaging applications are mechanically recycled in South Africa. These materials are often picked, sorted and washed by hand before being processed. PS follows a similar process when it is sent to a recycling facility to be turned into recyclate. The plastic waste is granulated and extruded before being sold back to plastics manufacturers.
How PS packaging is recycled
Firstly, discarded PS packaging is collected by waste management companies and informal waste pickers working at local landfills. They source and collect the waste before baling them for transport. These bales of plastic waste are then taken to recycling facilities where the process begins.
The plastic bundles are undone and the waste materials are separated by polymer type and grade. Due to the many food contact applications of PS packaging, these materials will have various qualities and degrees of cleanliness. The PS waste is first cleaned to remove any dirt and food contaminants. PS should be scraped clean or rinsed in used dishwashing water. South African polystyrene recyclers that manufacture lightweight bricks and screeds don’t require the materials to be pristine. However, the cleaner the waste, the better.
The PS waste is then shredded into small bits. These particles are then fed into a large heated extruder which melts the plastic under pressure and extrudes it into ingots. These bars of PS polymer are then granulated or cut into pellets and packed for sale to plastics manufacturers. Recycled PS is used to manufacture numerous products, such as clothes hangers, picture frames, cornices, hair combs and plastic rulers.
PS can be reused in the home
This polymer is extremely lightweight and semi-flexible. Consumers should always aim to reuse their PS takeaway containers and sealable fruit punnets. Hamburger clamshells or grape punnets are ideal for storing leftover food in the fridge. Polystyrene cups can also be washed and reused for children’s parties where kids may drop cups on the floor by mistake. Plastic cutlery should always be cleaned and reused as it is ideal for picnics and large outdoor gatherings.
The flexibility, lightweight and non-toxicity of this polymer lends itself to reuse in the home, making PS a highly valuable packaging polymer. By reusing these products, consumers can save a lot of money. If discarding PS is necessary, at least it can be recycled, which benefits the local economy and the environment.
Plastics SA represents all sectors of the South African plastics industry. Together with our associations, we play an active role in the growth and development of the industry and strive to address plastics related issues, influence role-players and make plastics the material of choice.
Plastics SA has been mandated to ensure a vibrant and sustainable plastics industry in South Africa. The plastics sector is uniquely placed to meet the needs of a sustainable society and to deliver solutions to many challenges such as recycling, climate change, water scarcity, resource usage and energy recovery.