Longevity of 3DP resins?

[patmat]

I posted some images of model ships in the Gallery a while back, which were almost completely 3D printed. This brings up another topic: Longevity of our 3DP materials.

Museums and collectors of high quality model ships (and I'm sure, many other items) demand construction with long life in mind... 100 years is a common expectation. And indeed with model ships, some materials were used in the past that have not held up well... cotton for rigging, cast lead for fittings. "Lead rot" occurs in closed display cases, iirc, from trace acetic acid outgassing... fittings will actually crumble into piles of lead oxide dust, yuk!
So some will specify materials like wood, linen thread, and brass, and disallow casting resins, styrene, and CA glue-- because the latter haven't proven themselves for a century yet!

I expect that SLS nylon and most of our filament print materials will last nearly forever... but these are not the processes I'd use for fine detail ship parts. I'd use SLA and multi jet processes instead... and these just seem scary to me, with their UV-cured liquid resins.

I know we haven't had these for a century yet, but does anyone know of any sort of data that points towards long life expediencies for these resins? Or even data that says they are real trouble?

Risk factors that are known to affect some resins, leading to brittleness and cracking:
- UV exposure
- Ozone exposure
- Loss of plasticizers
- Heat
- Contact with random materials (paints, glues....)


TIA, PM

[Yancy]

I don't think there should be any issues with SLA prints lasting 100 years. Once they are cured, I thought it wasn't reversible. I dont' think UV should effect it much, and heat certainly shouldn't.