The properties of a blend depend on the characteristics of the constituent polymers as well as on the microstucture which is generated during the processing. Since the bulk phases of the blends had simple rheological properties, all nonnewtonian behavior can be unambiguously attributed to interfacial phenomena. Immiscible polymer blends exhibit interesting rheological behavior related to morphological changes. Rheology and structure of immiscible polymer blends filled. There seemed to be a specific temperature like critical flow temperature t cf of amorphous polymer. Four topics are presented, which were investigated by using the new system. In immiscible polymer blends, one of the phases may consist of drops which during. The flow induced microstructure has been studied on model systems of nearly. Rheological properties of petpc immiscible polymer blends. Effects of compatibilizer on immiscible polymer blends near.
Viscoelastic properties of immiscible polymer blends under. He is a fellow of the royal society of chemistry and a fellow of the new york academy of sciences. Exclusive localization of nanofillers at the interface of immiscible polymer blend has been confirmed to be effective in improving compatibility and facilitating the formation of nanofillernetwork with very low percolation threshold, while the rheology of such nanofiller compatibilized blends has seldom been investigated. Pdf on the rheology of immiscible blends researchgate. Rheological properties of immiscible polymer blends request pdf.
Velankara department of chemical engineering, university of pittsburgh, pittsburgh. Keestra materials technology, faculty of mechanical engineering, eindhoven university of technology, p. Materials in which a twophase microstructure exists are referred to as textured. Leading researchers from industry and academia, as well as from government and private research institutions around the world summarize recent. Polymer melts, polymer blends, miscible polymer blends. Laboratoire des materiaux polymeres et biomateriaux, umr 5223,istil, universite claude bernard, b. Rheology and morphology of model immiscible polymer blends with monodisperse spherical particles at the interface shailesh nagarkar and sachin s. Pdf investigating the morphologyrheology interrelationships in. Effects of shear during the cooling on the rheology and. Interfacial localization of graphene in cocontinuous polymer blends is shown to be effective in stabilizing the cocontinuous morphology and increasing conductivity with a low electrical percolation threshold. Immiscible polymer blend electrorheological er fluid ch 3 ch 3 sio ch 2 3 och 2 ch 2 o ch 3 ch 3 ch3 coo cn m n.
May 01, 2000 investigating the morphologyrheology interrelationships in immiscible polymer blends investigating the morphologyrheology interrelationships in immiscible polymer blends martin, p carreau, p. Rheology and morphology of concentrated immiscible polymer blends. Rheology and morphology development in immiscible polymer. The effects of the various parameters volume fraction of the two polymers, relative viscosity and viscoelasticity of the two phases. Rheology of polymer blends and nanocomposites 1st edition. The compatibilization effect of exfoliated graphene on. Instead of formulating a single droplet problem, i.
Rheology and morphology of model immiscible polymer blends with. Rheology of compatibilized immiscible viscoelastic polymer blends. Apr 16, 20 we show that the addition of solid particles to dropletmatrix blends of immiscible polymers induces massive changes in the rheology and the flowinduced structure even at loadings as low as 0. The overview closes with a discussion of blend morphology development in confined geometries. Nadkarni polymer science and engineering group, chemical engineering division. The addition of xgnp to ppps blend increased the tensile modulus and decreased elongation at break because of its rigidity and intrinsic mechanical characteristics. The structure and rheology of blends of immiscible polymers have been examined for more than three decades.
Morphological characterization of polymer blends is important for tailoring final properties of plastic products based on these systems. Generally speaking, these authors argued that the key factor for compatibilization efficiency of the organoclay is the initial interlayer. Morphology and rheology of immiscible polymer blends filled. Experimental results on polymer blends are summarized. Rheology of fumed silicapolydimethylsiloxane suspensions journal of rheology 61, 205 2017. The blend polymer model is the emulsion formed by a mixture of polypropylene pp with polystyrene ps in the proportion of pp10ps90. The magnitude of the departure from doiotha theory worked out for noncompatibilized blends was evaluated. The rheological behavior of immiscible polymer blends choi. Step strain experiments, journal of rheology on deepdyve, the largest online rental service for scholarly research with thousands of academic publications available at your fingertips.
Empirical relations, which have previously been proposed for the properties of miscible polymer mixtures, were found to be without merit in describing the obtained experimental results. Rheology is a branch of physics that deals with the deformation and flow of matter under stress. It provides readers with a solid grounding in the fundamentals of rheology, with an emphasis on recent advancements. Morphologically miscible blends showed welldefined semicircles in colecole plots, whereas immiscible ones showed immiscible drifts from the semicircle. Rheology and morphology of concentrated immiscible polymer blends the phase morphology is an important factor in the rheology of immiscible polymer blends. Pspe model viscoelastic immiscible blend compatibilized by two types of interfacial modifiers was investigated. Most polymer blends are immiscible giving rise to a coarse morphology, weak adhesion between phases, and in some cases poor mechanical properties. Given enough time, the internal disorder of the polymer system will eventually result in phase separation on a macroscopic scale. Interfacial characterization of immiscible polymer blends.
Reinforcement of flexible polymer chains with very high modulus graphene pellets leads to a more brittle and a stiffer blend. Herein, we present a systematic rheological study on nanosilica. Diffuse interface modeling of the morphology and rheology. Separation of the mixed polymers to neat fractions is another possibility in case of recycling. Dynamics and rheology of the morphology of immiscible polymer blends on modeling and simulation. For long residence time, a noticeable decrease of the. These were the aver age number values from manual calculation.
Nov 01, 2000 read nonlinear rheology of immiscible polymer blends. Velankar department of chemical engineering, university of pittsburgh, pittsburgh, pennsylvania 15261 received 4 august 2006. Citeseerx document details isaac councill, lee giles, pradeep teregowda. Polymer melts, polymer blends, miscible polymer blends, immiscible polymer blends, compatibilization, rheological properties and phase structures. Microstructure is determined by fluid properties and flow history, and it affects the rheological, optical, and transport properties of the mixture. Postprint authors version rheology of compatibilized immiscible viscoelastic polymer blends. Two or more existing polymers may be blended for various reasons. Rheology and morphology of model immiscible polymer. Diblock compatibilizers vs crosslinked reactive compatibilizers. The impact of viscosity and phaseseparation on the development of commercial products the mixing of two or more polymers is an aspect of technology that lately has received special attention because blending represents a new, easy, and ef cient method for obtaining advanced materials with special.
This chapter provides an overview of research areas in the field of miscible and immiscible polymer blend rheology. One reason is to achieve a material that has a combination of the properties of the constituents, e. Fourier transform rheology of dilute immiscible polymer. State of the art, new challenges, and opportunities jyotishkumar parameswaranpillai, sabu thomas, and yves grohens 1. Rheology and dynamics of immiscible polymer blends. Rheology and morphology of immiscible polymer blends. Morphology immiscible polymer blends rheology close relationship doi and ohta, 1991 interface tensor. In this study, the relationship between morphology and rheology is investigated, and the interfacial tension and the maxwell stress are shown to play important roles. In the first case the pellets of polystyrene and polypropylene were blended on the twinscrew mini extruder in the classical manner with. Investigating the morphologyrheology int errelation ships in immiscible polymer blends investigating the morphologyrheology int errelation ships in immiscible polymer blends martin, p carreau, p. Investigating the morphologyrheology interrelationships in.
In addition, the resulting phase structure has a decisive influence on the physical and mechanical properties of polymer blends, for example the toughness during dynamical loads, elongation at break and stiffness during tensile test, and also on flammability. Pla, ldpe, polymer blends, melt viscosity, flow activation energy. Rheology and morphology of model immiscible polymer blends. Filling the gap for a reference dedicated to the characterization of polymer blends and their micro and nano morphologies, this book provides comprehensive, systematic coverage in a onestop, twovolume resource for all those working in the field. It would be desirable if sorting the polymers from the waste stream could be realized in just one step with the required purity, however. If one wants to optimize the final structure of a blend it is thus essential to understand the interplay between rheology and morphology development. Rheology of immiscible polymer blends usually disobey the classical rules and needs to be studied with other theories specially designed for biphasic systems. The influence of carbon black on blends phase structure is evaluated. The thermal stability in the melt of petpc blends is a key limitation of the measurement time especially in presence of transesterification catalysts. Rheological properties of polymers scientific research publishing. The difference in morphology affected the complex shear modulus of blends below the specific temperature, t cf, but did play a major role in determining the complex shear modulus of blends at over specific temperature. Dynamics and rheology of the morphology of immiscible.
Generally speaking, these authors argued that the key factor for compatibilization efficiency of the organoclay is the initial interlayer spacing and its ability to reduce the interfacial tension and average. These are nonequilibrium structures where the morphology is determined by a combination of processing conditions, interfacial properties, and rheology. The aim of this work was the generation of a microfibrillar structure in immiscible polymer blends using a new technique. We show that the addition of solid particles to dropletmatrix blends of immiscible polymers induces massive changes in the rheology and the. The rheology of polymer blends is connected with the processing of polymer blends and is influenced by thermodynamics, morphology, and their evolution during testing. The material properties of heterogeneous polymer blends are crucially influenced by their morphology, i. The particles are capable of adsorbing at the pipdms interface, and hence addition of these particles is expected to significantly affect the breakup and coalescence of drops and.
Through its size and shape, the interface between the two phases determines how the components and the interface itself will contribute to the global stresses. The fundamental problems in two immiscible polymer blends, such as deformation, break. Dynamics and rheology of the morphology of immiscible polymer. Investigating the morphologyrheology interrelationships. Sabu thomas is a professor of polymer science and engineering at mahatma gandhi university india. When the constituents of the multiphase system are incompatible the phases are immiscible, and, depending on their relative amount, the microstructure can consist of droplets in a matrix, elongated fibrils or a. Effects of compatibilizer on immiscible polymer blends near phase inversion jeffrey d. Pdf dynamics and rheology of the morphology of immiscible. Diffuse interface modeling of the morphology and rheology of immiscible polymer blends b. If you have access to journal content via a university, library or employer, sign in here. Rheological and mechanical properties of pchdpeglass fiber composites. Polymer blends are physical mixtures of two or more polymers withwithout any chemical bonding between them. Next, this volume presents the rheological behavior of structurally complex polymeric materials including miscible polymer blends, block copolymers, liquidcrystalline polymers, thermoplastic polyurethanes, immiscible polymer blends, perticularefilled polymers, organoclay nanocomposites, molten polymers with dissolved gas, and thermosts.
Effects of compatibilizer on immiscible polymer blends. Morphology and rheology of compatibilized polymer blends. Technically, vital types of multiphase polymers such as compounds and blends are discussed. Rheology and morphology development in immiscible polymer blends. An evaluation of the doiohta theory for an immiscible. Instead of formulating a single droplet problem, it was assumed that there is a kind of structure of the interfaces, in which the interfacial area q and its anisotropy q ij are equilibrated due to the competition between flow and interfacial. Cocontinuous polymer blends are formed by melt blending two or more immiscible polymers to form multiple continuous interpenetrated networks. Quasielastic surface light scattering study and analysis in terms of static and dynamic scaling laws. Pdf rheology of a miscible polymer blend at the air. With highly immiscible polymer blends, the phase diagram is virtually all in the two phase region with the binodal curves virtually overlapping the y axis at 0 and 1. Theory, modelling and applications focuses on rheology in polymer nanocomposites.
Viscoelastic properties of binary blends of immiscible polymers with almost the same viscosity were studied under steady and transient shear flows in the light of the scaling relations in the. The behaviour of biphasic polymer fluids, containing newtonian components and subjected to simple shear flows is relatively well understood at present. Rheology of nanosilicacompatibilized immiscible polymer blends. While immiscible blend often follows predict able rheology pattern since they exhibit. A novel technique to estimate the characteristic dimension and size distribution of a polymer blend is proposed and tested. The importance of the rheological properties of polymer mixtures in the development of the phase structure is discussed. Rheology of nanosilicacompatibilized immiscible polymer.
Morphology and rheology of immiscible polymer blends under. Velankara department of chemical engineering, university of pittsburgh, pittsburgh, pennsylvania 15261. We concluded that stabilization mechanism of ppps blend by hydrophilic silica is the reduction of the interfacial tension whereas hydrophobic silica acts as a rigid. May 21, 2019 rheology and structure of immiscible polymer blends filled with carbon black. Morphology and rheology of immiscible polymer blends in. Rheology of compatibilized immiscible viscoelastic polymer. The behaviour of these simple blends will be discussed first, as it serves as a reference for.
A new method may be needed to determine the critical flow temperature of an amorphous polymer via the measurement of a complex. International journal of polymeric materials melt rheology. Rheology of polymer alloys and blends springerlink. Polymer alloy is an otherwise immiscible blend, which is compatibilized, with modified interphase and. Rheology and morphology of concentrated immiscible polymer. Liquid multiphase systems such as polymer blends or emulsions are ubiquitous in many applications, including plastic production, food processing, pharmaceutical and cosmetic production. Exclusive localization of nanofillers at the interface of immiscible polymer blend has been confirmed to be effective in improving compatibility and facilitating the formation of nanofillernetwork with very low percolation threshold, while the rheology of such nanofiller compatibilized blends. In addition, as the compounding temperature increases, the dispersed pmma phase became stratified, and more rubber particles, especially larger ones, migrated toward the pmma phase.
Blending immiscible polymers provides an economic alternative to synthesizing new polymers. Morphology and rheology of immiscible polymer blends filled with silica nanoparticles l. Rheological measurements have been used successfully in the past to probe the. The system considered in the work by lee and park was an immiscible mixture of polystyrene ps. The zero shear viscosity and the terminal relaxation time of the blends reflected this change in local chain mobility. The procedure is based on fourier transform rheology ftr and largeamplitude oscillatory shear experiments and exploits their. Introduction when two immiscible polymers are mixed a complex morphology is formed. Morphology and rheology of immiscible polymer blends under electric fields. Formation of a heterogeneous network facilitated by interfacially anchored hybrid nanosilica. The objective of polymer blending is a practical one of achieving commercially viable products through either unique properties or lower cost than some.
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