Materials & Compounding
Our input materials are mixed polyolefins (MPO), PE, PP and PS. Most are from post-consumer sources but some come from post-industrial and very occasionally, virgin sources. ImerPlast UK sorts and compounds these materials using compatibilizing additives which restore properties to the recycled end products.
Sorted for performance
At the end of their life, plastics are recovered in various ways by recyclers. Unless they come from a single large application such as agricultural mulch film, they are always a mix of plastics. Sorting takes place at Material Recovery Facilities (MRF) which sort the plastics using NIR (near infra red) detectors and bale them by polymer to a reasonable accuracy. Increasing amounts are mixed; these laminates and copolymers are sorted into dominant polymer type.
At ImerPlast UK, we purchase these bales; grind and wash them and put the flake through float/sink separators. This does not necessarily improve the accuracy of the polyolefin fraction as PE and PP both have a density of <1. The target polymer content is therefore usually in the 97-99% range. We also sort by color which allows us to offer a wide range of darker colors from our 'Sorted' product range.
Compounding to restore properties
This sorting inaccuracy results in some compromise to the properties of the final recycled polymer. At ImerPlast UK our aim is to restore these properties during the compounding process. We can achieve this by adding compatibilizing additives based on specialty coated minerals from the Imerys portfolio which confer specific properties such as higher density, improved stiffness, CLTE (coefficient of linear thermal expansion), HDT (heat deflection temperature), tensile strength and enhanced isotrophy as well as reduced costs.
Minerals from our portfolio include:
- Calcium carbonate
Compatibilizing additives - when used - are added at 5-15%.
We may also add UV stabilizers, anti-oxidants, processing aids, masterbatch etc. to meet specific needs.