A crystalline polymer of high molar mass has a lamellar thickness of 27.1 nm and a T m of 129. Another sample of the same polymer has a lamellar...

 A crystalline polymer of high molar mass has a lamellar thickness of 27.1 nm and a Tm of 129.0 °C. Another sample of the same polymer has a lamellar thickness of 17.2 nm and a Tm of 119.2 °C. The surface free energy of the fold surface is 89.3 mJ/m2. The heat of fusion of the polymer is 198 J/g.  The crystalline density is 0.98 g/mL. What is the equilibrium melting point of the polymer?

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