Depends on what you consider degraded, the only reason it would stop being recyclable is if it became too contaminated with foreign substances or exposure, which applies to anything.
Repeating plastics tends to damage them on a chemical level. The polymer chains break and shorten. This ends with the plastic being more brittle. Since 3d printed parts have already been remelted once, they have even more degradation than injection moulded parts.
I believe the recommended amount of recycled plastic is around 30% for PLA. Any more and the parts lose significant strength.
I personally would prefer us to accept that plastics aren’t really recyclable. It’s better to move towards renewable plastics like PLA, and treat the waste as biomass (either composted or burnt for energy.
I personally would prefer us to accept that plastics aren’t really recyclable. It’s better to move towards renewable plastics
Err … getting mixed signals …
What you are describing is exposure. There are plenty of build with 100% recycled plastic, so not sure where you are getting that 30%. I think you are perhaps thinking of the marketing material of PLA filaments that sell themselves as particularly ecofriendly because they include recycled materials, while I’m talking about builds made entirely out of things like recycled water bottles, which are made out of PET. PLA is more susceptible to exposure to sunlight, heat, and moisture, so rather than using it to hold beverages at that point you might want to skip plastic entirely. PLA itself is not recycled that much, but it is more biodegradable.
Exposure can cause similar effects. However, the act of heating the plastic to the temperatures needed to melt it and defirming it also damages the structure. It’s particularly obvious with pla, but all plastics suffer from it, to an extent.
And how many times do they recycle the filament until it’s too degraded to use?
Depends on what you consider degraded, the only reason it would stop being recyclable is if it became too contaminated with foreign substances or exposure, which applies to anything.
Repeating plastics tends to damage them on a chemical level. The polymer chains break and shorten. This ends with the plastic being more brittle. Since 3d printed parts have already been remelted once, they have even more degradation than injection moulded parts.
I believe the recommended amount of recycled plastic is around 30% for PLA. Any more and the parts lose significant strength.
I personally would prefer us to accept that plastics aren’t really recyclable. It’s better to move towards renewable plastics like PLA, and treat the waste as biomass (either composted or burnt for energy.
Err … getting mixed signals …
What you are describing is exposure. There are plenty of build with 100% recycled plastic, so not sure where you are getting that 30%. I think you are perhaps thinking of the marketing material of PLA filaments that sell themselves as particularly ecofriendly because they include recycled materials, while I’m talking about builds made entirely out of things like recycled water bottles, which are made out of PET. PLA is more susceptible to exposure to sunlight, heat, and moisture, so rather than using it to hold beverages at that point you might want to skip plastic entirely. PLA itself is not recycled that much, but it is more biodegradable.
Exposure can cause similar effects. However, the act of heating the plastic to the temperatures needed to melt it and defirming it also damages the structure. It’s particularly obvious with pla, but all plastics suffer from it, to an extent.