Materials science company Void Technologies has earned RecyClass approval for its VO+ cavitation technology, the company has announced. Cavitated Machine Direction Orientation - MDO - PE films produced using Void’s new ‘VO+ PE Masterbatch’ offer 35% material saving, achieved via density reduction and downgauging. Developed for specific use in polyethylene MDO film, the patented cavitation technology works by replacing solid plastic with micro- and nano-scale air pockets. The resultant films therefore have a reduced environmental footprint without any gas injection or heavy mineral fillers. The films also demonstrate a high opacity, achieved through light diffraction, making the use of TiO2 unnecesary.
The technology is suitable for use in a range of applications such as laminates, frozen food, wicketed bags, and flow wraps for confectionery.
VO+ films are produced by blending the masterbatch with PE as part of the film extrusion process, before the film is MDO stretched. The orientation process causes the VO+ additives within the masterbatch to separate from the primary polymer to create a non-breathable nano- and micro-voided structure. The combination of MDO and cavitation leads to improved film performance in terms of both puncture resistance and toughness.
Regarding the recyclability of the films, two benefits have emerged: VO+ PE films have low density – even when very high opacity is required – meaning the films will always float in separation systems, as opposed to conventional PE films, which often sink due to high loadings of TiO2 pigments. In addition, during the recycling process, VO+ films will turn from white to clear and will retain similar properties to recycled PE resins.
The technology has now been accredited as fully compatible with the European polyethylene recycling stream, paving the way for its adoption by film and packaging manufacturers across the European Union.