Thèse - Interfacial Rheology of Polymer Systems in the Molten State

Description :
Polymer systems are often made up of different entities. They can be polymer blends, formulated materials or reinforced polymer alloy. All these components have the capacity to organize and form multi-scale structures during their elaboration process. The latter often occurred in the molten state, under high temperatures and / or under radiation (laser, UV, ...).
The study of the interfacial rheological properties of these systems as well as the modeling of the link between the underlying physical parameters (viscosity, surface tension, interfacial tension, ...) allows a better control of the manufacturing processes and the resulting functional properties.
Nowadays, such studies are conducted at ambient temperature. In contrast, the studies carried out at the melt state are based on indirect methods in which contact angle measurements on substrate are correlated with the rheological properties. Moreover other works have been focused on morphological and rheological modeling for accessing interfacial tension.
In this respect, a relevant methodology will be developed. It consists in the implementation of various tensiometry techniques :

-  Direct measurement of surface and interfacial tension in static by the pendant drop method.

-  Direct measurement of viscosity and interfacial elasticity’s by the harmonic oscillating drop method.

-  Measurement of interfacial rheological properties in shear by the ’’Double Wall Ring’’ technique recently developed by TA Instruments.
To carry out such a study, reference materials will be chosen. These are :
i) model fluids probed at ambient temperature to study the relationship between rheological and resulting interfacial properties. ii) polymer systems in the molten state. In the latter case, special attention will be given to polymer / ionic liquids systems. These latter have the advantage of being stable at high temperatures. Their structure can be modulated according to the targeted property (physical affinity, reactivity) which in turn can influence the interfacial rheology.
The proposed thesis subject, which is largely multidisciplinary, includes close links between aspects relating to materials, rheology and a fine knowledge of the interfacial properties of the polymers in the molten state.
These works will be carried out within the IMP in close collaboration between professors from the pole of research ’’Properties & Functions’’ and those from the research group ’’Structure and Rheology : Processes and Modeling’’.

Candidate profile : Highly motivated students with a Master degree (M2) or an engineering degree (preferentially obtained in 2019) in the field of polymers, and / or soft matter physics. A prior knowledge on surface and / or interface tensiometry will be highly appreciated. Excellent oral communication is required, as well as a good level of English.

Application : Applications to be sent by e-mail should include a CV, a motivation letter, the latest score slips and references to contact. After a first interview, the best candidates will be auditioned by the MATERIALS doctoral school of Lyon to obtain a doctoral contract, via a subject-candidate ranking.

Deadline for application : 27th May 2019.

Location : Campus of INSA Lyon at Villeurbanne (F-69100) and Campus of INSA Lyon at Bellignat (F-01100).

Reference :

Date de démarrage : 01 octobre 2019

Durée : 36 months

Contacter :
Dr. M. YOUSFI ; Prof. A. Maazouz ; Prof. J. Duchet
INSA Lyon. The IMP Laboratory (Polymer Materials Engineering)- Bât. Jules Verne - INSA Lyon – 69100 Villeurbanne (France)
email :

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