test_moissonnage_selune
type: Agent

Polymacromonomers. Synthesis-Small Angle Neutron Scattering- Rheology. From the branched architecture to the conformation: hairy stars and cylinders at rest and under flow.
type: Distribution
access URL: https://theses.hal.science/tel-00086252
format: HTML
issued: 2026-05-09T17:36:52.723076
modified: 2026-05-09T17:36:52.703991

Polymacromonomers. Synthesis-Small Angle Neutron Scattering- Rheology. From the branched architecture to the conformation: hairy stars and cylinders at rest and under flow.
type: Dataset
contact point: Organization
  fn: CCSD
keyword: theses
keyword: micelle-models
keyword: polymacromonomeres
keyword: infoeu-reposemanticsdoctoralthesis
keyword: physphysphys-data-anphysics-physicsphysics-physicsdata-analysis-statistics-and-probabilit
keyword: rheology
keyword: diffusion-de-neutron-aux-petits-angles
keyword: elongated-polymer
keyword: polymeres-ramifies
keyword: rheologie
keyword: branched-polymers
keyword: modeles-de-micelle
keyword: small-angle-neutron-scattering
keyword: polymacromonomers
keyword: polymere-etire
landing page: https://theses.hal.science/tel-00086252
description: Polymacromonomers (PMs) are well-defined branched polymers resulting from macromonomer polymerisation. The PM investigated in this work have been prepared using anionic and ring-opening metathesis polymerizations, which can be carried out under ?living? conditions. Our final PMs (polystyrene (PS) branches and polynorbornene backbone) show a regular and narrow branch distribution. Our aim was to describe in a quantitative way the PM conformation. SANS was a key technique has it allowed us to label PMs without modifying their architecture. Different geometric models have been applied to fit experimental form factors, measured by SANS, such as form factors of micelles with spherical or cylindrical cores, for PMs in solution as well as in the melt. Architecture has been shown to strongly influence the PM conformation and their interactions with the environment. Furthermore, pure entropic demixion induced by the structure of PM has been evidenced under specific conditions in PM ? linear PS blends. Besides, rheological investigation has been performed to define dynamics of the PM relaxation, which strongly differs from that of linear polymers. Branches are responsible for the specific response of our PMs. Further understanding has been provided by investigating the relaxation of the chain conformation after a quick elongation step of PM/linear blends films using SANS. The relaxation rate and process appear to differ depending on the scale investigated, from the statistical unit to the global size. Complex interpretation of the spectra has been carried out using a modified micelle form factor (combination of an ellipsoidal core with the phantom model applied to describe the branches conformation).
issued: 2026-05-09T17:36:52.721011
language: fr
modified: 2026-05-09T17:36:52.721015