I am attempting to remove years of black hair dye and came across Scott Cornwall and his product Decolour. He makes a claim that if it doesn't work likely cause is hair plasticised due to using heat over 220 deg cel. Quote "If you use heated styling products such as hot irons you can seal this build up onto the hair, gluing down the cuticle layer, trapping in the silicone and making it difficult to remove.
In some instances a straightening iron can reach such a high temperature that the silicone molecule actually reaches boiling point and melts onto the hair shaft."
- See more at: http://scottcornwall.blogspot.com.au/2012/08/clarifying-hair-and-silicone-damage.html#sthash.iOCFISfw.dpuf
And Mandy Baldwin for colourB4 states "
However, if the hair is regularly subjected to heated appliances such as tongs and irons over 230 degrees the silicone can reach boiling point and melt. The silicone then re-hardens and encases the hair in a plastic shell." http://www.colourb4.com/help.html
Is there scientific merit to this? Can silicone boil, coat the hair shaft and remain there plasticised for ever?