the before and after should be up tonight,,
With a bit more research and some discussions with chemically minded mates i have came up with a theory on yellowing.
When i mentioned it to my girlfriend while holding a jar of fizzing stormies she shook her head and commented that i was now a nerd and uncool and i should get out skateboarding asap. :lol:
Anyway here is imperial nuts thesis on Molecular contamination removal from polymers.
when i started getting yellowed stormies i wondered as everyone does are they just dirty. The simple answer is yes, however they are not dirty as we know it.
Often i noticed that they were yellowed on different parts of their bodies or limbs , this is explained by different parts being made from different plastics. And experiements with craft knifes and toothpaste showed that the yellowing was IN the plastic not on it.
Also almost all had a "suntan effect" as they had been exposed only on one side or put simply as if exposeure to a certain direction had cause the yellowing to be predominatly on one side.
This did not always match the seams of the mould and often markedly different in comparison to the whiter side.
So my question was if the body is prone to yellowing due to it being certain type of plastic,, why only one side?? should not all aspects of the plastic be an even colour?
Which brought me to the cause,, i looked at compatabilty charts for differnt material with Hydrogen peroxide and discovered that often it is used for etching plastics and cleaning other polymers.
And the main aspect of the cause of the staining is HEAT.
When a plastic or polymer is exposed to heat its molecues expand leaving microscopic gaps these gap are vunerabale to contamination from particles such as dust and other substances such as sweat and oily residue from human hands.
So this conclusion explains both why the stain is like a Suntan as the area most affected by sun or light source is affected worst by yellowing (think or a figure lying on a shelf exposed to the sunlight or figures in an attic in a box and the ones closest to the nearest heat source yellow more)
It also explains why some figures yellow on different limbs as they are made of different plastic and have a different tolerance to heat than the neighbouring parts.
the process i am using above reverses that process coming a active cleaning solution with the ambient heat that put the dirt there in the first place.
I thought that all this might damage the plastic with frequent and prolonged expansion of the plastic , but actually this happens everyday with all our figures as the expand and contract on our display shelves and from heated lights in or cabinets.
it leaves some questions though ,, what exact plastic did they use for the figures that yellowed,, was it many types? are there some COOs or manufacturers more prone to yellowing,? Is this now chemical dusting??
What do folk think? anyone out there know anything more about plastics than my ramblings?
steve