Book ChapterDOI
Slip and friction of polymer melt flows
N. El Kissi,J.-M. Piau +1 more
- Vol. 5, pp 357-388
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In this article, a comprehensive view of friction curves with polymer melt slip over a significant range of slip velocities was proposed, based on using polymers with various molecular characteristics and analyzing the flow curves.Abstract:
Publisher Summary By using polymers with various molecular characteristics and analyzing the flow curves, it has been possible to propose a comprehensive view of friction curves with polymer melt slip over a significant range of slip velocities This chapter discusses slip with additives containing mixture This shows the role of the additives, the wall material and the surface state of the wall Later, linear slip between polymer and wall is discussed The main characteristic of this type of slip is that it occurs at all stress levels; it is difficult to observe experimentally because it supposes the use of ideal surfaces: perfectly smooth and developing no interaction with the flowing polymer The chapter also discusses the cohesive slip with weak interactions The occurrence of slip is highly dependent on the interaction developing between the polymer and the wall The initial situation, prevailing before flow, is called the mushroom regime and the friction law controlling slip is deduced theoreticallyread more
Citations
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Journal ArticleDOI
Extrusion Instabilities and Wall Slip
TL;DR: In this paper, the authors explore the evidence for slip, the possible mechanisms of slip, and the relation between slip and extrusion instabilities, and show that extrusion melts exhibit extrusion instability at sufficiently high levels of stress.
Journal ArticleDOI
Slip at Fluid-Solid Interface
TL;DR: In this article, the authors discuss slip at fluid-solid interface in an attempt to highlight the main issues related to this diverse complex phenomenon and its implications, and propose a new boundary condition for non-Newtonian fluids.
Journal ArticleDOI
The production of nanostructures by mechanical forming
TL;DR: The field of nanometre scale mechanical forming has seen rapid development with the arrival of high-resolution, massive parallel techniques such as nanoimprinting as discussed by the authors, but a more fundamental understanding of the mechanics and physics underlying the forming operations is only beginning to emerge.
Journal ArticleDOI
Effect of die entrance filtering on mitigation of upstream instability during extrusion of polymer melts
J.-M. Piau,S. Nigen,N. El Kissi +2 more
TL;DR: In this paper, the effect of porous media of different filtering rates placed at the entrance of an extrusion die, on the processability of polymer melts, both in the absence and presence of wall slip, was examined.
Journal ArticleDOI
Rheo-PIV analysis of the slip flow of a metallocene linear low-density polyethylene melt
Francisco Rodríguez-González,José Pérez-González,Lourdes de Vargas,Benjamín M. Marín-Santibáñez +3 more
TL;DR: In this article, the authors analyzed the continuous extrusion of a metallocene linear low-density polyethylene through a transparent capillary die with and without slip by rheometrical measurements and particle image velocimetry (PIV).
References
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Journal ArticleDOI
Organized monolayers by adsorption. 1. Formation and structure of oleophobic mixed monolayers on solid surfaces
Journal ArticleDOI
Instabilities in viscoelastic flows
TL;DR: In this article, the authors present a review of the latest developments as well as earlier work in this area, organized into the following categories: Taylor-Couette flows, instabilities in cone and plate-and-plate flows, parallel shear flows, extrudate distortions and fracture, Instabilities in shear flow with interfaces, extensional flows, and thermohydrodynamic instabilities.
Journal ArticleDOI
Wall Slip in Viscous Fluids and Influence of Materials of Construction
TL;DR: In this paper, the question of slip and the influence of materials of construction on the observed extrudate irregularities are examined for high viscosity molten polyethylenes. But the assumption of "no slip at the rigid boundary" is generally not valid for polyethylene above a critical shear stress of approximately 0.1-0.14 MPa, when either surface or gross irregularities are present in the extrudates.
Journal ArticleDOI
Silanation of silica surfaces. A new method of constructing pure or mixed monolayers
Journal ArticleDOI
Shear-dependent slippage at a polymer/solid interface
F. Brochard,P. G. de Gennes +1 more
TL;DR: In this paper, the authors discuss shear flows of a polymer melt near a solid surface onto which a few chains (chemically identical to the melt) have been grafted.