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Selected Works

1994

William MacKnight

Articles 1 - 9 of 9

Full-Text Articles in Engineering

Complexation Of Ionomers And Surfactant Molecules Of The Same Charge In A Nonpolar Solvent, William Macknight, Kirill N. Bakeev, Sergey A. Chugunov, Iwao Teraoka, Alexander B. Zezin, Victor A. Kabanov Dec 1993

Complexation Of Ionomers And Surfactant Molecules Of The Same Charge In A Nonpolar Solvent, William Macknight, Kirill N. Bakeev, Sergey A. Chugunov, Iwao Teraoka, Alexander B. Zezin, Victor A. Kabanov

William MacKnight

Complexation between sulfonated polystyrene ionomers and bis(2-ethylhexyl) sulfosuccinate
sodium salt (aerosol OT, AOT) surfactant molecules in m-xylene was studied by ultracentrifugation, vapor
pressure osmometry, viscometry, and dynamic light scattering. When the dilute ionomer solution is mixed
with the AOT soluti6n, complexation takes place for both the slightly aggregated state of AOT and reversed
micelles of AOT containing water. In the presence of excess AOT molecules, some of the AOT are free from
the ionomers, and there are well-defined limiting compositions for complexes of the ionomer and AOT and
for those of the ionomer and AOT micelles. The limiting composition depends …

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Dynamic Mechanical And Spectroscopic Study Of Ionomer Blends Based On Carboxylated Or Sulfonated Flexible Polystyrene And Rigid Poly(Diacetylenes) With Functional Side Groups, William Macknight, C. D. Eisenbach, J. Hofmann Dec 1993

Dynamic Mechanical And Spectroscopic Study Of Ionomer Blends Based On Carboxylated Or Sulfonated Flexible Polystyrene And Rigid Poly(Diacetylenes) With Functional Side Groups, William Macknight, C. D. Eisenbach, J. Hofmann

William MacKnight

The dynamic mechanical and infrared spectroscopic investigation of ionomer blends of poly-
(diacety1ene)-a nd polystyrene-based ionomers has shown that miscibility of this usually incompatible polymer
pair can be achieved through ion-ion interactions between the blend components. Microphase separation
is prevented through ionic contacts generated during the blend formation; a schematic model of mixing in
the blends is proposed.

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Compatibility Enhancement Of Blends Of Nylon 4 With Lithium-Neutralized Sulfonated Polystyrene, William Macknight, C. -W. Alice Ng, Michelle A. Bellinger Dec 1993

Compatibility Enhancement Of Blends Of Nylon 4 With Lithium-Neutralized Sulfonated Polystyrene, William Macknight, C. -W. Alice Ng, Michelle A. Bellinger

William MacKnight

No abstract provided.

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Blends Of Amorphous-Crystalline Block Copolymers With Amorphous Homopolymers. 2. Synthesis And Characterization Of Poly(Ethylene-Propylene) Diblock Copolymer And Crystallization Kinetics For The Blend With Atactic Polypropylene, William Macknight, Kazuo Sakurai, David J. Lohse, Donald N. Schulz, J.A. Sissano Dec 1993

Blends Of Amorphous-Crystalline Block Copolymers With Amorphous Homopolymers. 2. Synthesis And Characterization Of Poly(Ethylene-Propylene) Diblock Copolymer And Crystallization Kinetics For The Blend With Atactic Polypropylene, William Macknight, Kazuo Sakurai, David J. Lohse, Donald N. Schulz, J.A. Sissano

William MacKnight

No abstract provided.

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Application Of A Molecular Simulation Technique For Prediction Of Phase-Separated Structures Of Semirigrid Model Polyurethanes, William Macknight, Hun-Jan Tao, Cun F. Fan, Shaw L. Hsu Dec 1993

Application Of A Molecular Simulation Technique For Prediction Of Phase-Separated Structures Of Semirigrid Model Polyurethanes, William Macknight, Hun-Jan Tao, Cun F. Fan, Shaw L. Hsu

William MacKnight

A combination of a molecular simulation method and the Monte Carlo method has been
succe88fully utilizedto calculate phase diagrams of model polyurethanes. In our model, the entropic contribution
of the Flory-Huggins expression has been modified to incorporate the contribution arising from orientation
of hard segments. The constraint associated with chain rigidity of hard segments has been explicitly considered.
In addition, the interaction term has been modified to include the relative packing of hard segments. Phase
diagrams of various MDI-PPG model polyurethanes have thus been predicted utihhg these modifications.
The effecta of soft- and hard-segment lengths have been considered and the …

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Phase Behavior In Copolymer Blends Of Poly(P-Chlorostyrene-Co-O-Chlorostyrene) And Phenylsulfonylated Poly(2,6-Dimethyl-1,4-Phenylene Oxide), William Macknight, R. Vukovic, G. Bogdanic, Vjera Kuresevic, M. Tomaskovic, F. E. Karasz Dec 1993

Phase Behavior In Copolymer Blends Of Poly(P-Chlorostyrene-Co-O-Chlorostyrene) And Phenylsulfonylated Poly(2,6-Dimethyl-1,4-Phenylene Oxide), William Macknight, R. Vukovic, G. Bogdanic, Vjera Kuresevic, M. Tomaskovic, F. E. Karasz

William MacKnight

The miscibility of random copolymers of o-chlorostyrene and p -chlorostyrene [ P (oC1Stco-
pC1St)] with partially phenylsulfonylated poly (2,6-dimethyl-1,4-phenylenoex ide)
( SPPO) copolymers has been studied, using differential scanning calorimetry (DSC) to
establish Tg behavior. It already has been established that the isomeric effect of the chlorine
substitution on miscibility is large. Thus the para-chloro-substituted styrenic homopolymer
is miscible with all SPPOs containing more than - 5 mol % phenylsulfonylation, whereas
the ortho-chloro-substituted homopolymer is immiscible with the entire range of SPPO
copolymer compositions (and also with the respective homopolymers) . As a result of this
asymmetric behavior of the …

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Structure And Morphology Of Nylon 4 Chain-Folded Lamellar Crystals, William Macknight, M. A. Bellinger, Alan J. Waddon, E. D. T. Atkins Dec 1993

Structure And Morphology Of Nylon 4 Chain-Folded Lamellar Crystals, William Macknight, M. A. Bellinger, Alan J. Waddon, E. D. T. Atkins

William MacKnight

No abstract provided.

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Thermal Degradation Of Segmented Polyurethanes, William Macknight, Zoran S. Petrovic, Zoltan Zavargo, Joseph H. Flynn Dec 1993

Thermal Degradation Of Segmented Polyurethanes, William Macknight, Zoran S. Petrovic, Zoltan Zavargo, Joseph H. Flynn

William MacKnight

Thermal degradation of polyurethane samples was studied by a thermogravimetric method. The effect of soft-segment length and soft-segment concentration on activation energy of the degradation process was measured. Three methods of calculation gave activation energies at different stages of the very complex weight loss process. It was shown that at initial stages of the weight loss the process was dominated by hard-segment degradation. Activation energy of the whole process calculated by the Ozawa-Flynn method did not offer clear insight into the structure-stability relationship of polyurethanes. The second method showed that activation energy of the initial stage of degradation increased with …

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Viscoelastic And Morphological Study Of Ionic Aggregates In Ionomers And Ionomer Blends, William Macknight, Elliot P. Douglas, Alan J. Waddon Dec 1993

Viscoelastic And Morphological Study Of Ionic Aggregates In Ionomers And Ionomer Blends, William Macknight, Elliot P. Douglas, Alan J. Waddon

William MacKnight

No abstract provided.

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