We process gamma irradiated UHMWPE bars in a chamber that is heated to 150 deg C. We are getting an oily residue collecting on the water cooled chamber door. Could this residue be from the bars out gassing? The bars are irradiated at 50 & 75 kGy and when they return to us they are a light brown color; after heat treatment the bars are white. Where does that color go? I'm thinking that may be the cause of the oil.
Any help with this would be greatly appreciated.