We now use compostable lids for our coffee, tea and hot chocolate takeaway drinks, manufactured from CPLA.
What is PLA?
PLA is a compostable bioplastic which is created from plant sugars. PLA is an abbreviation of polylactic acid which is made from sugars such as corn starch, sugar cane or sugar beet. Industrial corn is the primary source crop at the moment which is grown using sustainable farming practices such as:
- Limiting the excessive use of pesticides and water
- Not sourcing from land with high biodiversity or high carbon areas.
- Avoiding aggressive agricultural processes.
- Managing greenhouse gas emissions on the farm.
- Adhering to strict labour laws.
- Protecting the natural eco-system surrounding farmland.
To extract the starch, corn plants are milled and this produces glucose. Through a fermentation process, the glucose is then converted to lactic acid. Through a series of chemical processes, the lactic acid is turned into a polymer which is then used to create resin.
The resin behaves just the same as traditional plastics would, which means they can be processed in lots of different ways such as extruding to create sheet material or into a film, injection moulded, cast or spun. It’s extremely versatile.
What is CPLA? – crystallised PLA for higher heat use.
PLA has a low melt point, so it’s used mostly for cold use, up to around 40ºC. But for higher temperatures such as for cutlery or lids for hot liquid, we use a crystallised form called CPLA. The process to create CPLA involves adding chalk as a catalyst then rapidly raising and lowering the temperature during production. This makes the crystalised form of PLA stable up to 90ºC.
PLA products biodegrade in under 12 weeks at a commercial composting site, but if you don’t have access to this then put used items in the general waste. This may seem contrary, but these products are made through low carbon processes using renewable materials so they are still a much better alternative to conventional plastics.
However, you should not place these products in standard recycling bins as they can harm the quality of recycling. They are designed to be composted.