The problem

Recycling of plastic waste into high quality products is facing obstacles caused by the plurality of materials used in plastic products. Even after plastic waste has been separated, a significant percentage of unknown contaminants, primarily other plastic types, remains in the material. This makes it more difficult to reuse the material in a high-quality product, as different types of plastic do not mix well when combined in production. To mitigate the negative effects of contaminations, mechanical recyclers can use various chemicals, such as compatibilizers and plasticizers, to ensure an acceptable material quality is obtained, and to minimize machine downtime.

In order to determine the extent to which the batch of plastic flakes are contaminated, recyclers often perform a range of laboratory tests. However, the methodologies used to gain insight are labor-intensive and lengthy processes that require a certain level of experience. Moreover, in most cases these tests do not provide accurate information and/or are based on a small sample which is not representative for a batch (e.g. truckload) of plastic waste.