A circular economy is an economic system, that is based on three principles:

  • minimizing waste and pollution
  • Keep products and materials in use
  • Regenerate natural systems

The Ellen MacArthur Foundation was launched to accelerate the transition to a circular economy. Since the topic affects the plastic industry as well, ENGEL was one of the first plastics machine manufacturers to join the Ellen MacArthur Foundation's initiative.

A priority task on the way to the circular economy is to open up a broader range of applications for processed plastic waste. Therefore, the industry is focusing on processing recycled material, improving process stability, and the trend towards design for recycling, to use recycled material also for higher quality products.

Process stability

Pic: Circular Economy Recycled material is naturally subject to greater batch variations than virgin material. An intelligent weight control assistance system ensures constant melt volume during injection and therefore a consistently high product quality, even with highly fluctuating raw material quality.

Processing recycled material

Another approach to using recycled materials more widely is multi-layered components with a core of recycled material embedded in virgin material. The proportion of recycled material that can be used in the core is essentially determined by the geometry of the molded part and the flow pattern in the cavity. By using this new process, that involves fusing the two melts prior to injection, unlike classic coinjection, you can reach a very high level of recycled content. What is also important is the grade continuity, ensuring that the products can also be easily recycled at the end of their service life.


Pic: ENGEL at K 2019 Circular Economy 2
Despite the complex component geometry of transport boxes, by using the skinmelt process a very high level of recycled content of over 50% can be achieved.

Designing for recycling means that the subsequent recycling process is taken into account as early as in the development of a new product, and that the requirements of the circular economy and sustainability are taken into account in the product design. Examples can be found in the composite lightweight design. In this lightweight process, fiber-reinforced prepregs with a thermoplastic matrix are overmolded with a thermoplastic from the matrix material's material group. The entire composite component consists only of thermoplastic and glass fibers and has the potential to be recycled at the end of its useful life.