Determination of Residual Volatile/Semi-Volatile Compounds in Cured Polyimide Films by Thermal Desorption / Gas Chromatography – Mass Spectroscopy
Project BackgroundThe retention of residual solvent or low molecular weight building blocks in coatings can adversely affect manufacturing processes and operation of the device in its application. Electronics, aerospace and medical device companies need to be able to measure the volatile/semi-volatile organic compounds which might be released during heating of their product. Whether the information need is for minimization of volatiles by selection of appropriate raw materials or processing conditions, troubleshooting a lot of material which is problematic or a concern for the volatiles released into the workplace environment, outgassing studies are one of the most prevalent concerns for many of our manufacturing clients.
The ProblemTwo cured polyimide films were provided by the client identified as ‘Good and ‘Bad’. The objective was to identify the volatile/semi-volatile compounds which are evolved when the samples are heated to 350 °C.
Comparison of Bad and Good TICsThe results are highlighted below:
- There is approximately two-times more water evolved from the Bad sample than from the Good sample. This additional water could come from additional imidization (i.e., additional cure during the analysis) or from residual water trapped in the thin polymer film during the initial cure.
- There is ca. four-times more NMP in the Bad sample as compared to the Good film.
- Low levels of n-butyl acetate, phenol, decanoic acid, N-cyclohexyl-2-pyrrolidone are detected in the Bad film but are not in the Good film.