Surface treatments and coatings

XPS, grazing angle (analyzed depth 2 nm) was used to determine the chemical composition and speciation of a reference Mylar film, and of a plasma treated Mylar film. 

The XPS signatures (elemental composition and carbon/oxygen chemical forms distribution) of the non-treated PET are in very good agreement with a theoretical PET. Hence, the analysed PET polymer is contaminant free (Si, N…). 

After plasma treatment, the shake-up characteristics of the PET structure are always observed, which indicates that the grafting thickness is < 2 nm and/or does not affect the aromatic structure of the PET. The plasma induces also nitrogen grafting, mainly as amide N-C=O form.

In addition, amine N-C, imide N(CO)₂ and carbonyl C=O are also detected and quantified.

Survey spectra and high resolution spectra are presented hereafter: 

Composition table (table I) and chemical environment table (table II) are presented hereafter : 

Theoritical PET :