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Search Publications by: Kalman Migler (Fed)

Displaying 151 - 175 of 214

Rheology, Processing and Electrical Properties of Multiwall Carbon Nanotubes/Polypropylene Nanocomposites

January 1, 2004

Author(s)

S B. Kharchenko, Kalman D. Migler, Jack F. Douglas, Jan Obrzut, E A. Grulke

Flow Induced Coating of Fluoropolymer Additives: Development of Frustrated Total Internal Reflection Imaging

December 1, 2003

Author(s)

S B. Kharchenko, P M. McGuiggan, Kalman D. Migler

In the extrusion of linear low-density polyethylene (PE), fluoropolymer-processing additives (PPA) are used to eliminate the surface defect known as sharkskin by coating the die wall and inducing slip at the PPA/PE interface. We describe an in situ optical

Novel Microstructure in Polymer Blends Sheared Under Confinement

December 1, 2003

Author(s)

Jai A. Pathak, Kalman D. Migler

In this review article, we discuss the implications for the morphology of an immiscible polymer blend, or in general, an emulsion, in the limit when the two length scales, viz., the average droplet size and characteristic experimental length scale, become

Droplet-String Deformation and Stability During Micro-Confined Shear Flow

October 1, 2003

Author(s)

Jai A. Pathak, Kalman D. Migler

We have performed experiments on model emulsions of polyisobutylene (PIB) and poly(dimethylsiloxane) (PDMS) to quantify the effect of confinement on deformation and stability of droplets and strings (threads) under flow. It is known from some of our

Suppression of Capillary Instability of a Polymeric Thread Via Parallel Plate Confinement

July 1, 2003

Author(s)

Y Son, Nicos Martys, John G. Hagedorn, Kalman D. Migler

We investigate the stability of a polymer thread imbedded in a matrix that is confined between two parallel plates. Utilizing a combination of experiments, numerical simulations (Lattice-Boltzmann) and surface area calculations we find substantial

Flow Induced Coating of Polymer Processing Additives: Development of Frustrated Total Internal Reflection Imaging

May 1, 2003

Author(s)

S B. Kharchenko, Kalman D. Migler, P M. McGuiggan

In the extrusion of polyethylene (PE), fluoropolymer-processing additives (PPA) are used to eliminate the surface defect known as sharkskin by coating the die wall and inducing slip at the PPA/PE interface. We describe a method to carry out in situ

Droplet-String Deformation and Stability During Microconfined Shear Flow

January 1, 2003

Author(s)

Jai A. Pathak, Kalman D. Migler

Cavitation of Polyethylene During Extrusion Processing Instabilities

December 1, 2002

Author(s)

Y Son, Kalman D. Migler

We present observations of cavitation that occur inside a capillary die during extrusion of a polyethylene. This phenomenon is observed over the last 1.5 mm of the capillary tube immediately upstream of the exit. We observe spontaneous formation of voids

Layered Droplet Microstructures in Sheared Emulsions: Finite-Size Effects

November 1, 2002

Author(s)

Jai A. Pathak, M C. Davis, Steven D. Hudson, Kalman D. Migler

We investigate the influence of confinement on the steady state microstructure of emulsions sheared between parallel plates, in a regime where the average droplet dimension is comparable to the gap width between the confining walls. Utilizing droplet

Structure Formation in Micro-Confined Polymeric Emulsions

August 1, 2002

Author(s)

Jai A. Pathak, Steven D. Hudson, Kalman D. Migler

Application of a shear field to a concentrated emulsion induces a complex spatial and temporal response. The behavior of a concentrated system is treated as an extrapolation of the well-understood behavior of isolated droplets (or of the behavior of two

Interfacial Tension Measurement Between Immiscible Polymers; Improved Deformed Drop Retraction Method

May 1, 2002

Author(s)

Y Son, Kalman D. Migler

This paper describes an improvement of the technique to measure interfacial tension in immiscible polymer blends. Our method is based on the droplet retraction method, in which one relates the kinetics of relaxation of a deformed droplet to the interfacial

Observation of the Cavitation Phenomena Upon the Gross Melt Fracture Regime in LLDPE Extrusion

May 1, 2002

Author(s)

Y Son, Kalman D. Migler

We present observation of a cavitation phenomenon inLLDPE eaxtrusion. In the gross melt fracture regime, cavitation was always observed in the first 0.5 mm to 1.5 mm upstream of the exit. We saw cavities at the wall form (seemingly out of nothing) to grow

Extensional Deformation, Cohesive Failure, and Boundary Conditions During Sharkskin Melt Fracture

April 1, 2002

Author(s)

Kalman D. Migler, Y Son, F Qiao, Kathleen M. Flynn

We measure the flow kinetics of a polyethylene extruded through the exit of a capillary tube in order to understand the nature of sharkskin, a surface roughness in the extruded material. In the absence of a polymer process additive (PPA), optical