A study undertaken by the University of Bradford and commissioned by Nampak Plastics has proven that it is feasible to produce a milk bottle using 50% food grade recycled HDPE (r-HDPE).
Currently, Nampak includes up to 10% r-HDPE in its milk bottles in line with its commitment as part of the Department for Environment, Food and Rural Affairs’ milk road map. Nampak aims to include 50% r-HDPE in its bottles by 2020.
Nampak business development director James Crick said: “The Bradford research has confirmed our confidence that the target of 50% r-HDPE can be realised. This is a significant step forward and we now plan to conduct our own blow-moulding processing trials using 30% r-HDPE to replicate Bradford’s experimental work under manufacturing conditions.”
Carried out by the University of Bradford’s Centre for Advanced Materials Engineering, the study assessed how the addition of variable levels of r-HDPE might affect both the processability and functionality of the material. It also quantified how much r-HDPE can practically be added to a bottle. Results showed that the recyclate grades assessed had very similar qualities to the virgin materials.
Dr Adrian Kelly and Dr Leigh Mulvaney-Johnson co-led the research. Dr Kelly said: “The research has shown that the type of polymer used by Nampak is sufficiently resilient to cope with a higher level of recycled content. Although we did find subtle changes to the materials at high recyclate concentrations and after numerous processing steps, this wasn’t at a level to detrimentally affect its strength, appearance or processability during manufacturing.”