What is polypropylene and NWPP?
Polypropylene is the material that the “supermarket green bags” are made from. It's most common use is in the production of medical gowns, caps, masks and gloves. It is actually called non-woven polypropylene (NWPP) as the cross thatched pattern on the material is stamped on to make it look woven. PP is a thermoplastic polymer - a type of plastic that can be melted down and recycle into such things as garden stakes, garden furniture and flower pots.
But isn't polypropylene just another plastic?
There is substantial proof that it's not just another plastic. Polypropylene is strong, well priced, can be made to any colour, and print options are vibrant and unlimited.
It is also recyclable and leaves a smaller ecological footprint than many other plastics.
The Greenpeace pyramid of plastics , (see below), is a ranking of plastics into four groups according to their hazardous characteristics.
PVC, the most problematic and polluting plastic, is at the top of the pyramid at number one, while biobased plastics, the least polluting are number four at the pyramid's base. Polypropylene (PP) is just above biobased plastics at number three along with PET (the material used to make recyclable plastic bottles).
Furthermore, Zero Waste South Australia produced a report stating that Polypropylene has lower greenhouse gas impact and energy use in manufacture than either paper or calico (including production of raw materials).
What makes NWPP so good to use as a fabric?
NWPP makes a tough water repelling cover that can be dyed and printed to any Pantone Matching System (PMS) colour. Even the most complex designs can be screen printed or heat transferred onto it. All buckles, zips, loops and studs are made from polypropylene (PP) and are recyclable.
You may find that some of your covers and backpacks at home contain a large component of PVC. PVC is cheap and tough but also highly toxic. From it's manufacture to it's disposal, PVC emits toxic, cancer causing compounds.
NWPP's strength to weight ratio and low cost makes it a suitable alternative to polyester or nylon.
Are NWPP covers really environmentally friendly?
The term ‘environmentally friendly’ implies that polypropylene leaves no ecological footprint. NWPP is manufactured in factories using fossil fuels, and so contributes to greenhouse gas emissions.
However, the evidence above combined with the fact that polypropylene contributes to waste reduction and the movement away from one-use products, means that its ecological footprint is smaller than that of similar alternatives.
Please make the effort to recycle polypropylene covers where facilities are available.
Where can I recycle my NWPP covers?
Most larger supermarkets including IGA, Coles and Woolworths provide wheelie style recycle bins. These are red and displayed prominently near the entrance of all stores.
Recycling facilities can also be found at local Stockland shopping centres. Officeworks stores also have red Planet Ark bins suitable for these covers.
Why are these NWPP covers called ‘green’ or ‘eco’ covers?
They were originally introduced by supermarkets under pressure to reduce their consumption of single use plastic covers that mostly ended up as land fill or litter.
People are encouraged to ‘say no to plastic covers’ as there is now a better alternative. NWPP covers are recycled in the same way as PET bottles and paper.