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Author Topic: Why do plastics turn white ????  (Read 3223 times)

Offline Les the Scientist

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Why do plastics turn white ????
« on: 13/03/2006 07:59:25 »
Ok, so you're in school and you bend your plastic ruler.... too far.  It's turned white at the point that suffers maximum stress.  Why ?


 

Offline Hadrian

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Re: Why do plastics turn white ????
« Reply #1 on: 13/03/2006 10:55:57 »
My guess is you diffusing light by disrupting the structure of the material. The stress is causing micro fractures. It must be something to do with these fractures being able to reflect the full septum of light waves.

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Offline daveshorts

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Re: Why do plastics turn white ????
« Reply #2 on: 13/03/2006 22:17:19 »
I seem to remember reading that it is due to the plastic crystalising - areas where it lines up back and forth in a regular way, these areas have different optical properites to the bits in between so they scatter light...?
 

sharkeyandgeorge

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Re: Why do plastics turn white ????
« Reply #3 on: 14/03/2006 11:47:46 »
in all substances you get plastic end elastic deformation the deformation remains elastic to the point where any force you apply does not result im permenant corruption of the structure when excess force is applied and permenant corruption takes place the structures makeup is permenantly changed in your plastic ruler this change involves the bonds in one direction breaking when this happens the refractive propeties change ands so does the colour.

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The Naked Scientists Forum

Re: Why do plastics turn white ????
« Reply #3 on: 14/03/2006 11:47:46 »

 

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