"MageKnight Figures Becoming Brittle?" Topic

I was checking one of my repaints, a Tree Golem, and some of its limbs had snapped off. Seems the plastic is becoming brittle with age.

I checked four more, though, and they were fine.

I don't know if this is the 'standard' material they used, or something special for models with fine, thin branches.

Almost all of my Air fix figures bought in the 80s and earlier are becoming so brittle that I can barely pick them up without something breaking.

MageKnight are presumably made from the "bendable" plastic similar to the Airfix range?
Odd thing with the Airfix figs. Iīve got the whole range from 1960 onwards. Sets like the Guards Band/Colour party, all from when they were first made (50 years ago!!!!)or Foreign Legion (1st issue, 48 years old!!)
Some are still bendable, some are like dry cheese and crumble if they are so much as looked at.
Different batches with different amounts of plasticiser ?
I remember some early airfix sets were either very soft, almost like rubber or slightly harder and that across different boxes of the same sets. I recall the consistancy of Airfix Guards/colour Party plastic in particular due to using the heads for Airgun ammo. Some, being harder plastic made good ammo, the softer ones not.
The plastic of the Airfix Guards Band …
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… is reviewed as being "Medium Consistency". Is that due to the reviewers not having the sets way back and "medium" is cover all description?

Doesnīt just effect old sets though
This set;
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came out in 2007. Itīs reviewed as being "very soft plastic" but it appears they are so soft the plasticiser evaporates at high speed making them very brittle.

More like not enough antioxidants in different batches or injection moulding temperature was to high etc. Lots of variables can affect thermoplastic lifespans.

Or thermoset of course!

I don't have anything scientific, but I came across something discussing how most plastics become brittle, over time. I, too, have experienced this brittle effect, with Mage Knight figures, as well as other plastic figures. It is something which, I "think", is related to UV light. Sorry, that is all I remember about it. Not a plastics expert. These are just the bits which come to mind. Cheers!

I remember having airfix figs go brittle in the late 70s early 80s, particularly a WWI French set, not sure when those specific figs were actually produced.