This lab experiment illustrates the use of differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA) in the measurement of polymer properties. A total of seven exercises are described. These are dry exercises: students interpret previously recorded scans. They do not perform the experiments. DSC was used to determine the percent crystallinity of a polypropylene (PP) dog bone before and after it was pulled on an Instron machine. Using DSC, the percent crystallinity of a polyethylene terephthalate (PET) preform was determined and compared with a PET pop bottle. DSC was also used to explore the effect of molecular weight on the glass transition temperature of a series of polystyrene standards. Using a combination of DSC and IR spectroscopy the plastics in automobile headlights and taillights were identified. The same two techniques were also used to examine two commercial nylon samples: fishing line and a tea bag. TGA was used to examine the filler-reinforcement content in a series of PP samples. TGA was also used to examine the rubber tread of an automobile tire. Moisture, elastomers plus extender oil plus additives, carbon black, and filler content were measured.

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