Recyclates in Smartphones: What Requirements Sustainable Plastics Really Need to Meet

Recyclates Put to the Test: Requirements for Materials in Electronics

What challenges did Fairphone face with regard to materials?

Joe Liu: Environmental and social sustainability are key priorities for Fairphone, which is why the requirements for materials in terms of carbon footprint and durability are particularly high. It was crucial to achieve both a 100% post-consumer recycled content and exceptionally high impact resistance. The material had to pass demanding tests such as the 1.2-metre drop test in accordance with MIL-810G, as well as a free-fall test comprising 1 million cycles. At the same time, material purity – particularly for semi-transparent components – presents a major challenge during development.

How were these requirements met in terms of the material?

Liu: These challenges were resolved through targeted refinement and optimisation of the material formulation. Through precise adjustments, the impact resistance of the recycled material was significantly improved, making it suitable even for demanding applications.

The use of recycled materials can reduce global warming potential by up to 80%.

Joe Liu, Application Development Engineer MOCOM

Processing and Performance: What Recyclates Can Achieve – and What to Bear in Mind

Are there differences compared to virgin materials – and what advantages do recycled materials offer?

Liu: Compared to conventional virgin materials, the components initially exhibited visible weld lines; however, these were resolved through optimised mould venting. At the same time, the material offers very good flow properties and is therefore particularly suitable for thin-walled components in injection moulding. A key advantage also lies in the reduction of CO₂ emissions: using this material can lower the global warming potential of a smartphone case by around 80% compared to virgin material.

Recyclates in Smartphones: Practical Tips for Processors

What should processors pay particular attention to when using recyclates?

Liu: Success factors for the use of recyclates are:

• Optimise mould venting to avoid surface defects such as weld lines
• Control dwell times to prevent material degradation
• Keep shear forces moderate to stabilise material properties
• Make targeted use of flow behaviour, particularly for thin-walled components
• Involve material development at an early stage to reconcile application and recycling requirements

If these factors are adhered to, stable production of high-quality components made from recycled polymer compounds can be ensured.

Background:

The Fairphone is regarded as one of the prime examples in the electronics industry of a device that consistently uses recycled materials and ensures transparency in material flows.

• In this article, you will read about "7 ways in which the Fairphone uses plastics sustainably"

Author: Elena Blume | K-Mag

Elena Blume has been writing for various industry magazines for eight years and joined the K-Mag editorial team in 2021. She is particularly interested in topics related to innovative plastics solutions that contribute to sustainability and address current challenges relevant to industry and society.

At a glance

• Recyclates must meet high standards of impact resistance and material quality for use in smartphones.
• Material formulation and processing together determine component performance.
• In injection moulding, optimised process parameters such as venting, dwell time and shear are crucial.

Key Takeaway:

Sustainable plastics also work in high-tech products – provided that material development and application are consistently considered together.