Water impacts on PLA

[yellowshark 153]

I have been told that cuffs we made for attaching a motion sensor to the wrist are to be used by the British elite swimming squad. This was not a target sport discussed when we produced them and I am wondering if there is any potential impact on the PLA construction with continued use in water. Does anyone have any ideas/knowledge on this?

 

[nick-foley 5]

Should not present any problems.

 

[jameshs 42]

I put a PLA printed part with interconnecting pieces which had an interference fit in the pond for 6 months - no effect!

I also immersed a similar object in washing up powder - no effect

I put another in the garden in full sunlight (UK) for 6 months - no effect

But the unprinted filament I have found to be quite susceptible to age and storage conditions, but not the printed part.

James

 

[anon4321 16]

http://iepas.net/using-pla-for-long-term-outdoor-applications/

 

[SandervG 1,521]

How about Chloride?

 

[nallath 1,123]

PLA is hydroscopic. This means is sucks up water, a bit like a sponge. It will swell up somewhat if this happens (This is why PLA must be stored dry!). If something is biodegradable, it will generaly not stand water for a long time, especially not the chloride of a pool.

I'd recommend using ABS or coating the PLA with PVC glue. Although i'm not quite sure if those are able to stand the chemicals in a pool.

 

[yellowshark 153]

Thanks guys. I must admit that my thoughts had overlooked the chemicals present. The thought of sitting in a pool for 24 hours does not appeal! I have dropped a line to Andrew Dent, director of Faberdashery, who I know is a materials expert and I will post an update with any additional information I obtain.