For each of the following pairs of polymers, plot and label schematic specific volume-versustemperature curves on the same graph [i.e., make separate plots for parts (a) to \((\mathrm{c})]\) (a) Linear polyethylene with a weight-average molecular weight of \(75,000 \mathrm{~g} / \mathrm{mol}\); branched polyethylene with a weight-average molecular weight of \(50,000 \mathrm{~g} / \mathrm{mol}\) (b) Spherulitic poly(vinyl chloride) of \(50 \%\) crystallinity and having a degree of polymerization of 5000 ; spherulitic polypropylene of \(50 \%\) crystallinity and degree of polymerization of 10,000 (c) Totally amorphous polystyrene having a degree of polymerization of 7000 ; totally amorphous polypropylene having a degree of polymerization of 7000

Answer: The specific volume-temperature curves are affected by the differences in molecular structures and properties as follows: a) Linear polyethylene has a higher crystalline phase and shows a steeper decrease in specific volume with increasing temperature compared to branched polyethylene, which has a lower crystalline nature and follows a shallower curve. b) Spherulitic PVC has a shorter chain length and a more compact structure than spherulitic polypropylene, resulting in a slightly lower specific volume-temperature curve. However, both have similar changes in specific volume with respect to temperature due to their similar crystallinity levels. c) Amorphous polystyrene has a higher glass transition temperature than amorphous polypropylene, leading to a more pronounced plateau in its specific volume-temperature curve at higher temperatures.