Electron Microscopy and Inverse Gas Chromatography

Garbassi and co-workers [15] have the reviewed the subject of polymer surface analysis including surface characterisation techniques using a wide variety of spectroscopies and measurement of contact angles and surface force. Also, studies on surfaces and applications of surface science, including wettability, adhesion, barrier properties, biocompatibility, reduction of friction, and wear resistance, were carried out. 

The volatile characteristics of all three amide-cured epoxy powders studied were an unidentified compound and melamine. The source of the melamine is not clear but it has been suggested that dicyandiamide decomposes to cyanide during curing. Cyanide can react with dicyanamide to form melamine. However, cyanamide was not observed among the volatilised products. 

Most identified compounds gave observable molecular ions in electron impact mass spectrometry. Chemical ionisation mass spectrometry (CIMS) with isobutane was carried out to determine the relative molecular masses. In all instances the quasi-molecular ion was M + 1 with a relative abundance of 10% - no M + 57 was observed. Some compounds were identified on the basis of their mass spectra only because no reference compounds were obtainable. 

Other polymers that have been examined by evolved gas analysis include PVC [16-18], polystyrene (PS) [19-22], styrene-acrylonitrile copolymers [23-25], polyethylene and PP [26-32], polyacrylates and copolymers [33-39], PET and polyphenylenes and polyphenylene 

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