Exceptionally High Melting Temperature of Polymer Crystal with Fully Extended Chains Prepared via Topochemical Polymerization and Its Analysis Based on Nonlinear Modified Hoffman–Weeks Approach

High Resolution Image Download MS PowerPoint Slide One of the important parameters characterizing semicrystalline polymers is the melting temperature, which is linked to the lamellar thickness. However, within reasonable experimental time scales, the range of achievable lamellar thicknesses is limited, which makes the validation of theory difficult. Herein, we prepared polymer crystals of polymuconate with fully extended chains via topochemical polymerization. The melting temperature of the as-prepared polymer was found to be 217 °C. In contrast, the same polymer exhibited melting temperatures ranging from 148 to 156 °C after crystallization from the melt at various crystallization temperatures within the accessible experimental range. This extremely large difference in melting temperature cannot be explained by linear extrapolation of the Hoffmann–Weeks plot. We show that the experimental data can be described by the nonlinear Hoffmann–Weeks approach and discuss the applicability of the nonlinear Hoffmann–Weeks approach.