Thermogravimetric analyzer test samples

Thermogravimetric analyses of PDMS nanocomposites were performed with Mettler Toledo thermogravimetric analyzer (model TGA-DTA). The tests were run with samples of 10 mg at a heating rate of 10°C/min from 25°C to 700 C, in nitrogen atmosphere. 

Poly(ethylene terephthalate)s modified with increasing amounts of 5-sodiosulfo-isophthalic acid were prepared and char formation analyzed by thermogravimetric analysis at 600°C. Samples were heated at a rate of 20°C/min under a nitrogen flow of 50 ml/min. Char testing results are provided in Table 1. 

The thermogravimetric analysis (TGA) provides information especially on the content of metallic catalyst particles in the sample. When performed in air, the carbon species will be oxidized to give volatile gaseous products way below 1000 C, whereas the metal portion is-in parts or completely-transformed into its oxides and remains in the crucible as such. Analyzing this residue thus allows for quite an accurate assay of the metal in a nanotube sample. It may be up to 30% (m/m) depending on the quality of the material under test. The portion of amorphous carbon, on the other hand, can only be insufficiently determined by TGA. 

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