Confinement and distribution of the composition in semicrystalline/amorphous miscible blends of PEKK/PEI: a calorimetry study

Aude Belguise (1, 2) , Sabine Cantournet (2) , Victor Fabre (3) , Karine Le Gorju (3) , Valérie Gaucher (4) , Jean-François Tahon (4) , Bruno Bresson (1, 5) , Christian Fretigny (5) , François Lequeux (5, 1) , Helene Montes (5, 1)

1 ESPCI Paris - Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris
2 CDM - Centre des Matériaux
3 Research and Innovation Centre, Hutchinson SA
4 UMET - Unité Matériaux et Transformations - UMR 8207
5 SIMM - Sciences et Ingénierie de la Matière Molle (UMR 7615)

By combining small-angle X-ray scattering and differential scanning calorimetry measurements, we analyze the widening of the glass transition measured for miscible mixtures of semicrystalline PEKK chains and fully amorphous PEI chains. The calorimetric analysis reveals that the amorphous interlamellar phase is subject to confinement effects. In addition, we measure wide composition distributions for the amorphous interlamellar and interfibrillar phases. We quantitatively identify, through careful analysis of the signals, the fraction and average composition of each amorphous phase and the composition distribution. We conclude that the final distribution of the polymer chains that do not crystallize in the interlamellar and interfibrillar phases results from the crystallization dynamics of the mixtures.

Mots clés: Crystallization; Glass transition; Polyethylenimine; Quantum confinement; Phase transitions

Domaines: Polymères; Chimie

Aude Belguise, Sabine Cantournet, Victor Fabre, Karine Le Gorju, Valérie Gaucher, et al.. Confinement and distribution of the composition in semicrystalline/amorphous miscible blends of PEKK/PEI: a calorimetry study. Macromolecules, 2021, 54 (16), pp.7364-7376. ⟨10.1021/acs.macromol.1c00344⟩. ⟨hal-03324936⟩