Interface rheology

The concepts of interface rheology are derived from the rheology of three-dimensional phases. Characteristic for the interface rheology is the coupling of the motions of an interface with the flow processes in the bulk close to the interface. Thus, in interface rheology the shear and dilatational stresses of the interface are in equilibrium with the corresponding shear stress in the bulk. An important feature is the compressibility of the adsorption layer of an interface in contrast, the flow elements of the bulk are incompressible. As a result, compression or dilatation of the adsorption layer of a soluble surfactant is associated with desorption and adsorption processes by which the interface tends to reinstate the adsorption equilibrium with the bulk phase. 

This crude distinction between adhesive and cohesive wear mechanisms is probably oversimplified in the sense that it neglects many aspects of the interactions between bulk deformation modes and interface rheology. It has, however, the merit of making a clear distinction between wear processes which can, to some extent, be related to known bulk failure properties and... 

Interface Surface film properties Interface rheological properties Interface tension... 

This chapter provides a broad overview of the subjects of polymer blends and lonomers. Specific topics concerning polymer blends Include the thermodynamics of mixing of polymer-polymer pairs, polymer Interfaces, rheology, and mechanical properties. For lonomers, the chemistry, structure, rheology and solution properties are discussed. 

P. G. de Gennes, Physics of Polymer Surfaces and Interfaces, edited by Isaac C. Sanchez (Butterworth-Heinemann, Burlington, MA (1992), Chap. 3, pp. 55-71 J. L. Goveas and G. H. Fredrickson (1992), Apparent slip at a polymer-polymer interface, Eur. Phys. J. B2,79-92 (1998) R. Zhao and C. W. Macosko, Slip at polymer-polymer interfaces Rheological measurements on coextruded multilayers, J. Rheol. 46, 145-67 (2002). 

Mohammed et al. [55] published a series of papers in which they probed the rheology, interfacial tension, surface pressure, and compressional modulus of crude oil-water interfaces with and without added demulsifiers under thermal and electrical fields. They observed that with short aging times of the crude oil-water interface, the interface rheology could be characterized as substantially viscous, but with very little elastic character. They demonstrated that thick viscoelastic films tended to accumulate in aged films and that some demulsifiers prevented such accumulations. 

Zhao, R., Macosko, C. W., Shp at Polymer-Polymer Interfaces Rheological Measurements on Coextruded Multilayers, 7. Rheo. 46, 1, 2002, 145-167. 

Zhao Rui, and Macosko Christopher. Slip at polymer-polymer interfaces Rheological measurements on coextruded multilayers. J. Rheol. 46 no. 1 (2002) 145-167. 

Fuller GG, Vermant J. Complex fluid-fluid interfaces Rheology and structure. Annu Rev Chem Biomol Eng 2012 3 519-543. 

FUippone G, Romeo G, Aciemo D. Role of interface rheology in altering the onset of co-continuity in nanoparticle-fiUed polymer blends. Macromol Mater Eng 2011 296(7) 658-665. 

The properties of t have been studied quite extensively. It is an interface rheological property which manifests many of the characteristics of the bulk shear yield stress although the numerical values of t are significantly less than the bulk analogue. Thus to a first order... 

Tonck A, Georges J M and Loubet J L 1988 Measurements of intermoiecuiar forces and the rheology of dodecane between alumina surfaces J. Coiioid interface Sc/. 126 150-5... 

Borwankar R P and Case S E 1997 Rheology of emulsions, foams and gels Curr. Opin. Coiioid interface Sc/. 2 584-9... 

Most properties of linear polymers are controlled by two different factors. The chemical constitution of tire monomers detennines tire interaction strengtli between tire chains, tire interactions of tire polymer witli host molecules or witli interfaces. The monomer stmcture also detennines tire possible local confonnations of tire polymer chain. This relationship between the molecular stmcture and any interaction witli surrounding molecules is similar to tliat found for low-molecular-weight compounds. The second important parameter tliat controls polymer properties is tire molecular weight. Contrary to tire situation for low-molecular-weight compounds, it plays a fimdamental role in polymer behaviour. It detennines tire slow-mode dynamics and tire viscosity of polymers in solutions and in tire melt. These properties are of utmost importance in polymer rheology and condition tlieir processability. The mechanical properties, solubility and miscibility of different polymers also depend on tlieir molecular weights. 

Lequeux F 1996 Struoture and rheology of wormlike mioelles Curr. Opin. Colloid Interface Sc/. 1 341-4... 

Based on the underlying physical chemistry of surfactants at interfaces, important features of foam stmcture, stabiHty, rheology, and their interrelationships can be considered as ultimately originating in the molecular composition of the base Hquid. 

Viscoelastic polymers essentially dominate the multi-billion dollar adhesives market, therefore an understanding of their adhesion behavior is very important. Adhesion of these materials involves quite a few chemical and physical phenomena. As with elastic materials, the chemical interactions and affinities in the interface provide the fundamental link for transmission of stress between the contacting bodies. This intrinsic resistance to detachment is usually augmented several folds by dissipation processes available to the viscoelastic media. The dissipation processes can have either a thermodynamic origin such as recoiling of the stretched polymeric chains upon detachment, or a dynamic and rate-sensitive nature as in chain pull-out, chain disentanglement and deformation-related rheological losses in the bulk of materials and in the vicinity of interface. 

The dry adhesive films on the two substrates to be joined must be placed in contact to develop adequate autoadhesion, i.e. diffusion of polymer rubber chains must be achieved across the interface between the two films to produce intimate adhesion at molecular level. The application of pressure and/or temperature for a given time allows the desired level of intimate contact (coalescence) between the two adhesive film surfaces. Obviously, the rheological and mechanical properties of the rubber adhesives will determine the degree of intimacy at the interface. These properties can be optimized by selecting the adequate rubber grade, the nature and amount of tackifier and the amount of filler, among other factors. 

A. Tonck, J. M. Georges, J. L. Loubet. Measurements of intermolecular forces and the rheology of dodecane between alumina surfaces. J Colloid Interface Sci 72(5 150-163, 1988. 

Interface and its Rheological Implications, Clay Minerals Society, Boulder, CO, USA (1992). 

Eckert, E.R.G. and Drake, R.M. Analysis of Heat and Mass Transfer (McGraw-Hill, New York, 1972). Edwards, D. A., Brenner, H. and Wasan, D. T. Interface Transport Processes and Rheology (Bulterworth-Heinemann, Oxford, 1991). 

Intermolecular Forces and the Rheology of Dodecane Between Alumina Surfaces, J. Colloid Interface Sci., Vol. 126, No. 1, 1988, pp. 150-163. 

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