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1984

Selected Works

Articles 1 - 14 of 14

Full-Text Articles in Engineering

Method And Apparatus For Division Employing Associative Memory Us:4466077, Robert Iannucci, James Kleinsteiber Dec 1983

Method And Apparatus For Division Employing Associative Memory Us:4466077, Robert Iannucci, James Kleinsteiber

Robert A Iannucci

No abstract provided.

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Equilibrium Melting Point Depression For Blends Of Isotactic Polystyrene With Poly(2,6-Dimethylphenylene Oxide), William Macknight, Joaquin Plans, F. E. Karasz Dec 1983

Equilibrium Melting Point Depression For Blends Of Isotactic Polystyrene With Poly(2,6-Dimethylphenylene Oxide), William Macknight, Joaquin Plans, F. E. Karasz

William MacKnight

The melting behavior of pure isotactic polystyrene (iPS) and blends with poly(2,6-di­methylphenylene oxide) (PPO) have been investigated by differential scanning calorimetry (DSC). Evidence for interaction between the blend components has been detected from melting point depression studies and by examining the composition dependence of the glass transition temperature. The interaction parameter has been evaluated via the Flory-Huggins approximation of the thermodynamic mixing of two polymers, which yielded an average value of x = -0.17 for the range of compositions analyzed. This result is in agreement with the interaction parameter values derived from the negative heat of mixing for a-PS/PPO liquid …

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Carboxylation Of Poly(2,6-Dimethyl-1,4-Phenylene Oxide) And Thermal Properties Of Blends With Atactic Polystyrene, William Macknight, S. Xie, F. E. Karasz Dec 1983

Carboxylation Of Poly(2,6-Dimethyl-1,4-Phenylene Oxide) And Thermal Properties Of Blends With Atactic Polystyrene, William Macknight, S. Xie, F. E. Karasz

William MacKnight

No abstract provided.

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Aqueous Phase In A Perfluorocarboxylate Membrane, William Macknight, Noel G. Boyle, Michael D. Coey, A. Meagher, Vincent J. Mcbrierty, Yoshitomo Nakano Dec 1983

Aqueous Phase In A Perfluorocarboxylate Membrane, William Macknight, Noel G. Boyle, Michael D. Coey, A. Meagher, Vincent J. Mcbrierty, Yoshitomo Nakano

William MacKnight

A perfluorocarboxylate membrane has been characterized by dynamic mechanical relaxation, NMR on 1H and 19F, and 57Fe Mossbauer spectroscopy of the ferric salt. Results are similar to those reported for perfluorosulfonate membranes, indicating that the specific charged end group has little influence on the structure or behavior of the aqueous phase. Exchanged ions in the membranes at ambient humidity and above are not directly coordinated by sulfonate or carboxylate groups, but by water. Precipitation of ferric hydroxide in a ferric membrane reexchanged with KCl is inferred from the Mossbauer spectrum at 4.2 K and confirmed by NMR relaxation times. 

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Dynamic Mechanical Properties Of Perfluorocarboxylate Ionomers, William Macknight, Y. Nakano Dec 1983

Dynamic Mechanical Properties Of Perfluorocarboxylate Ionomers, William Macknight, Y. Nakano

William MacKnight

Two perfluorocarboxylate ionomers of different ion-exchange capacities (IEC) of 1.25 and 1.80 mequiv /g were studied to determine their dynamic mechanical behavior, water uptake, and rates of neu­tralization. These polymers consist of a fluorocarbon backbone containing short side chains on the end of which the carboxylate functionality resides. They are quite similar in many ways to the more familiar perfluorosulfonate ionomers that have been studied extensively. Methyl esters, free acids, and sodium, potassium, cesium, silver, barium, magnesium, and tetrabutylammonium salts were examined. In the case of the 1.25 mequiv / g IEC resin, a two-phase morphology consisting of a fluorocarbon …

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Polyurethane-Urea Elastomers As Working Substances In Rubber Heat Engines, William Macknight, R. E. Lyon, D. X. Wang, R. J. Farris Dec 1983

Polyurethane-Urea Elastomers As Working Substances In Rubber Heat Engines, William Macknight, R. E. Lyon, D. X. Wang, R. J. Farris

William MacKnight

No abstract provided.

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Deformation Studies Of Polymers By Time-Resolved Infrared Spectroscopy Iv: A Modified Approach, William Macknight, S. E. Moles, S. L. Hsu Dec 1983

Deformation Studies Of Polymers By Time-Resolved Infrared Spectroscopy Iv: A Modified Approach, William Macknight, S. E. Moles, S. L. Hsu

William MacKnight

No abstract provided.

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Elastometric Ionomers, William Macknight, R. D. Lundberg Dec 1983

Elastometric Ionomers, William Macknight, R. D. Lundberg

William MacKnight

No abstract provided.

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Dynamic Mechanical Properties Of Methacrylic-Acid-Grafted Polyethylene Films, William Macknight, Y. Nakano, H. Omichi Dec 1983

Dynamic Mechanical Properties Of Methacrylic-Acid-Grafted Polyethylene Films, William Macknight, Y. Nakano, H. Omichi

William MacKnight

No abstract provided.

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Melting Point Depression In Multicrystalline Blends: Pvf(2)/Pmma, William Macknight, Joaquin Plans, F. E. Karasz Dec 1983

Melting Point Depression In Multicrystalline Blends: Pvf(2)/Pmma, William Macknight, Joaquin Plans, F. E. Karasz

William MacKnight

No abstract provided.

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A Polymer Blend Exhibiting Both Upper And Lower Critical Solution Temperature Behavior: Polystyrene/Poly(O-Chlorostyrene), William Macknight, Sherrie L. Zacharius, F. E. Karasz Dec 1983

A Polymer Blend Exhibiting Both Upper And Lower Critical Solution Temperature Behavior: Polystyrene/Poly(O-Chlorostyrene), William Macknight, Sherrie L. Zacharius, F. E. Karasz

William MacKnight

No abstract provided.

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Properties Of Parially Cured Networks. 1. Curing Kinetics Of A Model Network, William Macknight Dec 1983

Properties Of Parially Cured Networks. 1. Curing Kinetics Of A Model Network, William Macknight

William MacKnight

Model networks based on a,w-dihydroxypoly(propylene oxides) and tris(4-isocyanatophenyl) 
thiophosphate were prepared. The curing kinetics were followed up to 97% conversion by measuring the 
change in the infrared absorption intensity of the isocyanate stretching band at 2200-23?0 cm·1. The ov􀄖􀄗all reaction kinetics were found to be second order and are described well by a scheme cons1stmg _ of competitive 
consecutive order reactions up to an extent of reaction of about 85% (the gel point). The observed inc􀄫ease in reaction rate at conversions greater than 85% is attributed to an increase in intramolecular reactions.

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Aggregation Of Ion Pairs In Sodium Poly(Styrenesulfonate) Ionomers: Theory And Experiment, William Macknight, W. C. Forsman, J. S. Higgins Dec 1983

Aggregation Of Ion Pairs In Sodium Poly(Styrenesulfonate) Ionomers: Theory And Experiment, William Macknight, W. C. Forsman, J. S. Higgins

William MacKnight

Theory of the effect of ion-pair clustering on chain dimensions was compared with mean-square radii of gyration determined on poly(styrenesulfonic acid) ionomers by small-angle neutron scattering (SANS). Reasonable agreement between theory and experiment was obtained by setting the surface energy of cluster formation (the only arbitrary parameter) equal to 8.9 kcal/mol of ion pairs. Since theory predicted more ion pairs per cluster than could be accommodated in spherical clusters, lamellar cluster formation was assumed. Theory predicted about 15 and 12 ion pairs per cluster for polymer containing 1.9 and 8.5 mol % ionic repeat units, respectively. The data suggest, however, …

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Phase Behavior In Copolymer Blends Of Polystyrene And Poly(0-Chlorostyrene-Co-P-Chlorostyrene), William Macknight, Gerrit Ten Brinke Dec 1983

Phase Behavior In Copolymer Blends Of Polystyrene And Poly(0-Chlorostyrene-Co-P-Chlorostyrene), William Macknight, Gerrit Ten Brinke

William MacKnight

No abstract provided.

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