Compositional Analysis of Electrical Switch Contact Carriers
SourceSmall amounts of carbon fibers (about 5%) were determined in samples containing polyphenylene sulfide (PPS), inorganic filler (glass in this case), and polytetrafluoroethylene (PTFE) by means of thermal analysis using both thermogravimetry (TG), and differential scanning calorimetry (DSC). Two different, but related, methods were used to quantitatively determine the contents of the sample. The first, which was nominally called the “Indirect Approach,” utilizes DSC for the determination of the polymeric components and TG for the determination of the residue (inorganic fillers or glass or both). The amount of carbon is then determined by difference. The second method, which was nominally called the “Direct Approach,” utilizes DSC for the determination of PTFE and TG for the determination of all other components. The agreement between the two methods is good.