How to make effective reuse of waste plastics

Ben Smye explains how one of its partner suppliers is incorporating recycling into its materials, and how design engineers can use it to design greener projects

Recycling and reusing waste products has been high on the agenda for people across the world for the past 20 years, with it climbing ever higher up the list in recent years. 

If you’ve been through the fruit and vegetable aisle in a supermarket in the past few years, you’ll have probably come across ‘wonky’ produce. 

These are fruits and vegetables that don’t meet the conventional size or shape requirements of producers. In the past, such produce was often discarded on the basis of being unprofitable, but as awareness of food waste has grown, wonky produce has grown in popularity.

We can think of wonky produce as symbolic of the shift in society towards a less wasteful, more resourceful economy.

We’re seeing a similar mentality shift in the materials industry, not least of all for plastics. 

Plastic products have been widely manufactured and used for the past half a century and most of this plastic is still around today, albeit not in a way that is providing value to people. 

A team of scientists analysed production data and concluded that 91% of plastics are not recycled. And if you take a swim at the beach, you’ll see evidence of this ― plastic litter is everywhere.

However, the recycling of plastic products at the point of use is only part of the solution. 

During the plastic production process and product manufacturing, waste material is usually produced due to the subtractive manufacturing process that many manufacturers use. 

Often, this scrap material is not considered to be useful and it becomes waste.

As a materials sourcing platform and database, we at Matmatch strive to help design engineers choose the ideal materials for their projects, whether that is based on its impact strength, density or sustainability.

So, we’re always keen on highlighting the green credentials of our suppliers. 

And in tackling plastic waste in manufacturing, WELA-Plast is producing high quality thermoplastics from the waste of manufacturers.

The company uses the production waste and faulty batches from manufacturers, as well as overproduction from plastic-processing companies and commercial waste recycled granulates, to produce a multitude of plastics ideal for extrusion, injection moulding and film applications. 

These plastics include high-density polyethylene (HDPE), low-density PE (LDPE), polystyrene, acrylonitrile butadiene styrene (ABS) and polypropylene (PP).

Crucially, there is little difference between the properties of these recycled materials and newly created plastics. 

As such, it’s more environmentally-friendly to use these recycled materials, and as we’ve seen governments around the world introducing new ways of taxing manufacturers for the use and end-of-life management of plastic products, this can lead to lower overall costs.

If, for example, a design engineer is developing a new range of laser printers and is determining the material to use for the roller gears, using a recycled thermoplastic such as an ABS for injection moulding would offer the same application benefits – good natural lubricity, high heat resistance, durability – but in a more resourceful way.

It’s a seemingly simple step, but it’s one that takes us closer to the circular economy where nothing is wasted, only reprocessed and reused. 

A bit like buying wonky produce, choosing to source recycled materials is a decision that allows design engineers to get the same net result without the same environmental impact.

Ben Smye is head of growth at materials comparison website Matmatch.