Biodegradable Phone Cases versus Regular Plastic Cases
Choosing a phone case is often an after thought from all the time spent choosing the right phone. When we do take the time choosing a case, often two factors come to mind. How well will it protect the case and does it look nice. Rarely does the thought of material come into it.
A good phone case should be able to protect the phone against common bumps and drops. If looked after well enough, it may even last as long as the phone itself. Many people choose to have more than one case over the lifetime of the phone regardless of the condition of the original case. So thinking about the afterlife of the case is just as important as the recyclability of the phone itself.
Many regular phone cases are made from poly-carbonate. A tough plastic that works well at protecting a phone and can be recycled with common plastic as long as it does not include extra elements such as glitter or metal parts. Environmentally speaking, since this can be recycled its not the worst material. However this relies on people adding it to recycling and still depends on none sustainable oil based plastic designed not to decompose.
Biodegradable cases can be made from numerous types of plastic and this is why the term biodegradable is so vague as its not regulated enough. Some biodegradable plastics simply break down into smaller toxic microplastics entering the environment.
Our iPhone case we have chosen to use, are made up two main elements, PLA and PBAT, making them non toxic to the environment and compostable, reducing to a natural state that can feed the soil.
Our dark tone iPhone cases are made up of soil and vegetable extracts giving it a very earthy note in smell. Whilst our lighter coloured cases are using a bamboo extract.
PLA is a derivative from plant based material. 'Polylactic Acid' often made from elements such as vegetable starch, will eventually break down to non toxic elements. However making a case with PLA by itself, while possible, would be very stiff and potentially brittle against drops. PLA would also take longer to decompose in a compostable environment without some additional assistance.
PBAT is a derivative from oil, however, unlike other oil based plastics which are designed to last as long as possible, PBAT is an extraction from oil which will decompose to a non toxic state. Oil after all is a natural produce made from decomposed fish pressurised under the sea bed over thousands of years. It just all depends on how you process it.
PBAT by itself wouldn't have the structural strength to produce a phone case, but adding PLA to it provides a good balance of strength and durable flex ideal for making phone cases. The PBAT also decomposes much faster than PLA in a compostable environment, so a compound of the two speeds up the PLA's breakdown.
In an ideal world we would find an alternative to using any oil based ingredients, however, whilst some development is being made, at this time PBAT is an effective ingredient that is non toxic.
Are these phone cases home compostable? Yes, you can add them to your own compost bin, however the advertised 160 days to 1 year breakdown applies to a perfect compostable environment often found in an industrial scale (your local recycle center should be able to help). For home composting it would be recommended if possible, to shred the phone case into smaller pieces before composting to speed up the breakdown, otherwise it may take a couple of years to decompose in a warm, damp, oxygenated environment with other vegetable waste. Once fully broken down, it will work with the rest of the compost and aid at feeding new vegetation.