BPF Recycling Group Position Statement on Bioplastics
The term "bioplastic
" has become a marketing tool and as yet is not properly defined. There is a CEN committee working on definitions of the word because it is so complex and can include:
• bio-derived plastic
• degradable plastic, both biodegradable and oxodegradable
• plastic intended for medical applications
• a combination of two or more of these
The recycling industry has no problem with non-degradable bio-derived plastic, since these are usually not distinguishable from conventionally derived plastic in terms of formation, properties, recyclability etc.
There are considerable concerns about degradable plastics of all sorts.
Generally it is not possible to distinguish the degradable plastic from conventional by visual inspection. Depending on the degrading agent (bio or oxo) then mechanical/optical sorting may be possible but will never be 100% effective. If degradable material enters the conventional plastics stream and fully degrades in the recycling process it may change the characteristics and specification of the conventional material it is be mixed with. Equally if it does not fully degrade it may continue to do so in the finished recycled product, leading to premature failure e.g:
Some recyclers report that just one PLA bottle can contaminate a 20 tonne batch of PET by changing the crystallinity such that the material becomes opaque.
Much recycled film material goes into damp proof membrane production and there is concern about the long term stability of such material.
Degradable plastics represents a significant cost to recyclers because they have paid for material they cannot use, must pay to sort it and then pay for its disposal to landfill
It is often claimed that degradable plastics are suitable for composting. However, composters have no sophisticated sorting equipment and so cannot tell the difference when plastic bags arrive at their receiving bay. To avoid the risk that the material may be conventional plastic they reject all plastic materials which are then sent for landfill (again at a cost)
The general view of the recycling industry is that conventional and degradable plastics should never be mixed and that specific applications for degradable materials should be selected to ensure that this never happens
Some degradable suppliers claim there is no effect on recycling but when examined closely these claims rely on the conventional plastic being considerably reduced in specification already; something which is clearly not true given the extremely high quality materials that are being recycled and are displacing virgin.
Oxodegradable suppliers claim their materials are different. The recycling industry view is that it is for any degradable supplier to prove to the satisfaction of the recycling and potential user industries that their materials have no adverse effect. It should not be necessary for the recycling industry to carry out or fund such testing.
The BPF Recycling Group believes that degradable plastics should only be used in applications where they will not become mixed with conventional plastics at end of life.
For more information on Bio-Based and Degradable Plastics CLICK HERE