Browsing Scholarly Works, Department of Chemical Engineering by Issue Date
Now showing items 1-20 of 141
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A systematic study of the effect of casting solvent on the bulk properties of linear SBS block copolymers
(American Institute of Physics, 1978)Using a well_characterized series of styrene_butadiene triblock copolymers, a systematic study was carried out to determine the influence of casting solvent, used for film preparation, on the final mechanical properties. ... -
Sub-Tg annealing studies of rubber-modified and unmodified epoxy systems
(American Institute of Physics, 1978)Epoxy network systems based on DGEBA (bisphenol_A_diglycidyl ether) and NMA (nadic methyl anhydride) systems modified with the low molecular weight CTBN (carboxyl_terminated butudiene_acrylonitrile copolymer)rubbers were ... -
Comparison Of The Rheological Properties Of Concentrated-Solutions Of A Rodlike And A Flexible Chain Polyamide
(AIP Publishing, 1979)The steady state shear rheological properties of solutions of a rodlike polyamide, poly_p_phenyleneterephthalamide (PPT), in 100% sulfuric acid have been compared with those of solutions of a flexible chain polyamide, nylon ... -
Rheological Properties Of Liquid-Crystalline Solutions Of Poly-P-Phenyleneterephthalamide in Sulfuric-Acid
(AIP Publishing, 1980)The steady state shear and linear viscoelasticproperties of both isotropic and liquid crystalline solutions of the rigid chain polymer poly_p_phenyleneterephthalamide in sulfuric acid have been determined. Both the primary ... -
Rheological Properties Of Copolyester Liquid-Crystalline Melts .1. Capillary Rheometry
(AIP Publishing, 1981)Rheological properties of two copolyesters which exhibit liquid crystalline behavior in the melt state were determined using an Instron capillary rheometer. The two polymer melts with nematic liquid crystalline order ... -
Role Of Solvent Nature on Rheological Properties Of Nylon 6,6 Solutions
(AIP Publishing, 1981)The rheological properties of concentrated solutions of nylon 6,6 of various molecular weights in various solvents have been determined in steady shear flow. Four solvents including 90% formic acid,m_cresol, 97% H2SO4, and ... -
Initial Results of a Flow Birefringence Study of the Hole Pressure for Polymer Melts
(AIP Publishing, 1984)The initial results of this study on a polymer melt shows that, for the present experimental conditions, stress field asymmetry has a negligible effect on the validity of the HP theory and that the theory may be extended ... -
Rheological Properties Of Liquid-Crystalline Copolyester Melts .2. Comparison Of Capillary And Rotary Rheometer Results
(AIP Publishing, 1985)In an earlier paper capillary rheometer results were presented for two liquid crystalline copolyesters consisting of 60 mole % and 80 mole % p_hydroxybenzoic acid (pHBA) and polyethyleneterephthalate (PET). In this paper ... -
Studies on The Transient Shear-Flow Behavior Of Liquid-Crystalline Polymers
(AIP Publishing, 1986-06-01)An understanding of the flow behavior of liquid crystalline polymers (LCP's) is of immense practical value because of the potential to form high modulus materials from these polymers. These fluids exhibit a high degree of ... -
Comparison Of Flow Birefringence Data with A Numerical-Simulation Of The Hole Pressure
(AIP Publishing, 1988-08-01)The penalty_Galerkin finite_element method is used to simulate the flow of a polystyrene melt over a rectangular slot placed perpendicular to the flow direction. The White_Metzner constitutive equation is used with a Carreau ... -
Methanol decomposition on single-crystal Cu₂O
(American Institute of Physics, 1990-05-01)CH₃OD decomposition has been studied over the stoichiometric, nonpolar (111) and polar, copper_terminated (100) surfaces of Cu₂O. Thermal desorption studies for monolayer coverages of methanol at 90 K show similar conversions, ... -
Transient Flow Of Thermotropic Liquid-Crystalline Polymers in Step Strain Experiments
(AIP Publishing, 1990-07-01)The transient response of two thermotropic liquid crystalline polymers (a copolyester of 60 mol_% p_hydroxybenzoic acid, PHB, and 40 mol_% poly(ethylene terephthalate), PET, and a copolyester of PHB and 2_hydroxy_6_naphthoic ... -
Photoemission and low-energy-electron-diffraction study of clean and oxygen-dosed Cu₂O (111) and (100) surfaces
(American Physical Society, 1991-01-01)The geometric and electronic structure of clean and oxygen-dosed Cu₂O single-crystal surfaces was studied with x-ray and ultraviolet photoelectron (UPS) spectroscopies and low-energy electron diffraction. The nonpolar (111) ... -
An Evaluation Of The Doi-Ohta Theory For an Immiscible Polymer Blend
(AIP Publishing, 1996-01-01)The theory developed by Doi and Ohta was evaluated for its ability to predict the rheology of an immiscible polymer blend. The theory describes the additional stresses arising as a consequence of interfacial tension in two ... -
Polyelectrolyte DNA conjugation and genetic transformation of an animal
(United States Patent and Trademark Office, 1996-06-04)The present invention provides a method of obtaining an organism which has been characterized as having cells containing exogenous genetic material which includes any sequence of DNA that can be distinguished as exogenous ... -
Influence Of Molecular Weight Distribution on The Melt Extrusion Of High Density Polyethylene (HDPE): Effects Of Melt Relaxation Behavior on Morphology And Orientation in HDPE Extruded Tubular Films
(AIP Publishing, 1996-11-01)The influence of molecular weight distribution and extrusion processing variables on the morphological features and orientation of high density polyethylene (HDPE) uniaxially extruded tubular films was investigated. In ... -
Shear And Extensional Rheology Of Sparsely Branched Metallocene-Catalyzed Polyethylenes
(AIP Publishing, 2000-09-01)The purpose of this study was to identify any rheological effects that are consistent with the presence of sparse levels of long chain branching (LCB) in three commercial metallocene-catalyzed polyethylenes (MCPE) all of ... -
Spontaneous planarization of nanoscale phase separated thin film
(AIP Publishing, 2002-06-01)Structure of complex fluid at mesoscales is influenced by interfacial effects. We describe the dynamic response in such films to sudden change in interfacial tension. In a self-assembled block copolymer film, the monolayer ... -
Ratio of dynamic moduli and estimation of relaxation times
(AIP Publishing, 2002-07-01)In this paper, the theoretical interrelation between the ratio of dynamic moduli and the number and distribution of relaxation times required to fit the generalized Maxwell model to the data was investigated. Theorems were ...