Polymers protect people against contact with pollutants and pathogens, enable the manufacture of ultralight, high-strength car bodies, and make an essential contribution to the harvesting of regenerative energies like wind and solar power. And that’s just a fraction of the things that these powerful, versatile, transformable and resource-conserving materials can do. Their secret is that their composition can be tweaked to adapt them perfectly to the intended application.
The key lies partly in the very broad selection of available polymer types, but it is above all the special ingredients that producers and compounders use to achieve exactly the right characteristics. Additives help to adjust the polymer properties to users’ needs, whether soft and ﬂexible, rigid and flameproof, extremely tough and strong, coloured or bacteria-repellent. And producers guard their recipes very closely. The variations may be tiny, but they make all the difference in terms of marketing and use.
The huge variety of polymers in the market poses great challenges for recyclers processing waste plastics into materials that are fit for use in high-quality applications. This can be done more easily when single grades of plastics like PET bottles are processed. However, upcycling becomes diffcult – if not impossible – when the waste consists of similar plastics with only slight differences, so that the only solution is to downcycle them. One alternative is thermal recycling of waste, generating energy and heat.
Engaging and partnering
Polymer scientists are working hard to solve this problem but also rely on the experience and expertise of users in the feld. Signifcant increases in upcycling rates will only be achieved through well coordinated collaboration between polymer producers, compounders, processors and recyclers.
Would it make sense to add tracers to the polymers that would allow better analysis and sorting of grades? Or might it not be better to agree to reduce the volume of specifc types of polymers? There are no easy answers to these questions, but they can be more readily addressed with the help of experts.
And what better forum could there be than K 2019 for interdisciplinary exchanges of this kind?