A new understanding of entanglements in polymers applications to rheology and processing
- IBAR, JEAN PIERRE
- Pedro Antonio Santamaría Ibarburu Director
Defence university: Universidad del País Vasco - Euskal Herriko Unibertsitatea
Fecha de defensa: 07 June 2017
- Alejandro Jesús Müller Sánchez Chair
- Juan Francisco Vega Borrego Secretary
- Peter Heidemeyer Committee member
Type: Thesis
Abstract
In the type of research I propose, I look at polymer phusics from a different angle: I consider the statistics of a system consisting of a set of interactive conformers belonging to all the chains put together at once. The statistical system is no longer a single macromolecule mede up of covalently interactive conformers, although this situation is also studied. The system is the global set of conformers belonging to all macromolecules. I no longer attribute to a mean field the influence generated by the other molecules on teh configurational properties of a single chain (defining its entropy and enthalpy), I attribute a "grain-structure" to the field that describes the result of interactive coupling, i.e. I consider the existence of an inhomogeneous density of state due to local fluctuations of the interactions. The evolution with time of the state of interactions between the conformers, when the system is submitted to a mechanical force or to a temperature variation dewscribes the change of the physical properties.