4versionA. Analyzing Polymers -PC8 Below is a DSC thermogram…
4versionA. Analyzing Polymers -PC8 Below is a DSC thermogram of polyethylene-like polycarbonates with varying amounts of methylene in their polymer sequence (where n=2,4,6,8, or 10) according to the general structure also shown below. Note that no glass transition temperature is indicated on the thermogram for any of the polymers. A. (.4 pt) What is the Tc for the polymer PC8? B. (.4 pt) What is the Tm for the polymer PC8? C. (.6 pts) Which polymer has the highest percent crystallinity and briefly describe why? D. (.6 pts) Which polymer would be more susceptible to creep and briefly describe why? The same polymers were also analyzed with XRD and compared to high-density polyethylene (HDPE) E. (0.5 pts) Based on these results, which polymers have crystal structures similar to HDPE and which likely have different crystal structures? F. (0.5 pts) The plane indicated around 2Ɵ=30° has a miller indices of 210. Draw the plane. G. (1 pts) You’ve determined your % crystallinity for your PC8 sample is 54% and has a density of 120,000 g/cm3. Calculate the density of the density of completely amorphous PC8 if the density of completely crystalline PC8 is 200,000 g/cm3? Show all work H. (0.5 pts) You decided to run gel filtration chromatography (a form of size-exclusion chromatography) on your PC samples, but you forgot to label your samples. Which of your PC samples do you think corresponds to the darkest gray (furthest to the left) in your GPC plot and why?
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