The surface of polyethylene after being treated with cold plasma ...

[stephzh]

The surface of polyethylene after being treated with cold plasma using oxygen as the working gas is similar to the type of surface created when a spark is used to etch the surface of the same polyethylene material. Explain this similarity.
 
  What will be an ideal response?

Question 2

Wire and cable material is often crosslinked by electron beam irradiation. Why is this material crosslinked?
 
  What will be an ideal response?

[thall411]

Answer to Question 1

When the plasma reacts with the surface and oxygen is the working gas, the charged oxygen atoms react with the surface of the polyethylene to attach OH groups on the surface. OH groups are also attached to the surface when a spark is used to etch the surface because the high energy of the part breaks apart the oxygen in the air and ionizes it, thus causing an active site which can react with the polyethylene in much the same way that the plasma does.

Answer to Question 2

Wire and cable insulation is susceptible to stress cracking. Irradiation to cause crosslinks will tie the molecules together and prevent this stress cracking form occurring.

[stephzh]

Thanks for the timely response, appreciate it

[cici]

Excellent