Structure, morphology and crystallization of isodimorphic random copolymers: Copolyesters, copolycarbonates and copolyamides

Melt memory in propene–pentene isotactic copolymers: the case of defects hosted in the crystals

“…11,21,22,44–48 The stronger the interactions, the more pronounced the melt memory effect and the higher the increase in crystallization temperature in comparison with the standard crystallization temperature. 11,21,22,44–48 The disappearance of the melt-memory in isodimorphic copolyesters, where two comonomers co-crystallize in the same unit cell, has been interpreted as due to the disruption of intermolecular interactions. 43,44 In our apolar iPPC5 copolymers, the melt-memory is not due to intermolecular interactions and the co-crystallization of pentene units does not involve changes in molecular interactions.…”

“…11,21,22,44–48 The disappearance of the melt-memory in isodimorphic copolyesters, where two comonomers co-crystallize in the same unit cell, has been interpreted as due to the disruption of intermolecular interactions. 43,44 In our apolar iPPC5 copolymers, the melt-memory is not due to intermolecular interactions and the co-crystallization of pentene units does not involve changes in molecular interactions.…”

“…This result is rather surprising also considering that exactly the opposite result has been observed in the literature for other systems, such as copolyesters, where the incorporation of comonomers within crystals reduces or even erases the melt-memory. 43,44 However, as mentioned in the introduction, in polar polymers such as polyesters, poly(amides), polycarbonates or polyethers that contain several functional groups, the melt memory is directly related to the presence and strength of intermolecular interactions, such as dipole interactions or hydrogen bonds. 11,21,22,[44][45][46][47][48] The stronger the interactions, the more pronounced the melt memory effect and the higher the increase in crystallization temperature in comparison with the standard crystallization temperature.…”

“…43,44 However, as mentioned in the introduction, in polar polymers such as polyesters, poly(amides), polycarbonates or polyethers that contain several functional groups, the melt memory is directly related to the presence and strength of intermolecular interactions, such as dipole interactions or hydrogen bonds. 11,21,22,[44][45][46][47][48] The stronger the interactions, the more pronounced the melt memory effect and the higher the increase in crystallization temperature in comparison with the standard crystallization temperature. 11,21,22,[44][45][46][47][48] The disappearance of the melt-memory in isodimorphic copolyesters, where two comonomers co-crystallize in the same unit cell, has been interpreted as due to the disruption of inter-…”

“…11,21,22,[44][45][46][47][48] The stronger the interactions, the more pronounced the melt memory effect and the higher the increase in crystallization temperature in comparison with the standard crystallization temperature. 11,21,22,[44][45][46][47][48] The disappearance of the melt-memory in isodimorphic copolyesters, where two comonomers co-crystallize in the same unit cell, has been interpreted as due to the disruption of inter-…”