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Miscibility

Articles 1 - 14 of 14

Full-Text Articles in Engineering

Miscible Blends Of A Thermotropic Liquid Crystalline Polymer And Sulfonated Polystyrene Ionomers, Robert Weiss, Y. Ghebremeskel, L. Charbonneau Jul 2014

Miscible Blends Of A Thermotropic Liquid Crystalline Polymer And Sulfonated Polystyrene Ionomers, Robert Weiss, Y. Ghebremeskel, L. Charbonneau

Robert Weiss

The miscibility of a wholly aromatic thermotropic liquid crystalline polyester (LCP), Vectra® A, with lightly sulfonated polystyrene ionomers (SPS) was assessed. Blends were prepared by melt mixing in an intensive mixer. The sulfonation level and the choice of the cation used to neutralize the ionomer influenced miscibility. Zinc salts of an SPS with 5.3 mol% sulfonation were miscible at all compositions with the LCP, but lithium salts with the same sulfonation level formed two phases, a pure LCP phase and an ionomer-rich mixed phase. Zinc salts of an ionomer with 10.8 mol% sulfonation were also miscible with the LCP when …

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Miscible Blends Formed From Intrapolymer Repulsive Interactions: 2. Phase Behavior Of Blends Of Bisphenol A Polycarbonate And Zinc-Sulfonated Polystyrene Ionomers, Rui Xie, Robert Weiss Jul 2014

Miscible Blends Formed From Intrapolymer Repulsive Interactions: 2. Phase Behavior Of Blends Of Bisphenol A Polycarbonate And Zinc-Sulfonated Polystyrene Ionomers, Rui Xie, Robert Weiss

Robert Weiss

The phase behavior of mixtures of bisphenol A polycarbonate and the zinc salts of lightly sulfonated polystyrene ionomers (Zn-SPS) was studied as a function of the sulfonation level and the molecular weight of the ionomer. This system exhibits upper critical solution temperature (UCST) phase behavior and miscibility is attributed to intramolecular repulsion between the ionic and non-ionic groups of the ionomer. The cloud point temperature decreased with increasing sulfonation level of the ionomer over the range of 8.7–13.7 mol.%, and it inscreased with increasing molecular weight of Zn-SPS for a fixed sulfonation level. Fourier transform infrared spectroscopy revealed that no …

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Dynamics Of Spherulitic Growth In Blends Of Polypropylene Isomers, Rujul Mehta, Thein Kyu Jul 2014

Dynamics Of Spherulitic Growth In Blends Of Polypropylene Isomers, Rujul Mehta, Thein Kyu

Thein Kyu

The spatiotemporal growth of spherulites in blends of isotactic polypropylene (iPP) and atactic polypropylene (aPP) isomers has been investigated theoretically with the time-dependent Ginzburg–Landau equation, which consists of a nonconserved crystal order parameter and a conserved compositional order parameter. In the description of the total free energy, a local free energy density in the form of an asymmetrical double well, signifying the metastability and latent heat of crystallization, is combined with a nonlocal free energy term representing the interface gradient. In addition, the Flory–Huggins free energy for mixing between iPP and aPP isomers has been employed to account for blend …

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Effects Of Genistein Modification On Miscibility And Hydrogen Bonding Interactions In Poly(Amide)/Poly(Vinyl Pyrrolidone) Blends And Morphology Development During Coagulation, Chandrasekaran Neelakandan, Thein Kyu Jul 2014

Effects Of Genistein Modification On Miscibility And Hydrogen Bonding Interactions In Poly(Amide)/Poly(Vinyl Pyrrolidone) Blends And Morphology Development During Coagulation, Chandrasekaran Neelakandan, Thein Kyu

Thein Kyu

Miscibility characteristics of poly(amide):poly(vinyl pyrrolidone) (PA:PVP) blends containing a soybean-derived phytochemical called “genistein” have been investigated using differential scanning calorimetry (DSC) and polarized optical microscopy (POM). The occurrence of hydrogen bonding in the binary PA/genistein (PA/G) and PVP/genistein (PVP/G) pairs as well as their ternary blends has been confirmed by Fourier transformed infrared spectroscopy (FTIR). On the basis of DSC and POM data, the morphology phase diagram of PA:PVP/G blends is mapped out, which consisted of various coexistence regions such as isotropic, liquid + liquid, liquid + crystal, liquid + liquid + crystal, and solid crystal regions. Subsequently, PA:PVP membranes …

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Miscibility And Characterization Of The Ternary Crystalline System: Poly(Vinyl Butyral)/Poly(Vinyl Alcohol)/Nylon6, William Macknight, H. Jeong, M. Rooney, D. J. David, F. E. Karasz, T. Kajiyama Dec 1999

Miscibility And Characterization Of The Ternary Crystalline System: Poly(Vinyl Butyral)/Poly(Vinyl Alcohol)/Nylon6, William Macknight, H. Jeong, M. Rooney, D. J. David, F. E. Karasz, T. Kajiyama

William MacKnight

No abstract provided.

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Topological Effects On Blend Miscibility, William Macknight, W. L. Nachlis, J. T. Bendler, Roger P. Kambour Dec 1994

Topological Effects On Blend Miscibility, William Macknight, W. L. Nachlis, J. T. Bendler, Roger P. Kambour

William MacKnight

No abstract provided.

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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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Miscibility And Phase Behaviour In Poly(2,6-Dimethyl-1,4-Phenylene Oxide) And Poly(Fluorostyrene-Co-Bromostyrene) Blends, William Macknight, R. Vukovic, G. Bogdanic, Vjera Kuresevic, F. E. Karasz Dec 1987

Miscibility And Phase Behaviour In Poly(2,6-Dimethyl-1,4-Phenylene Oxide) And Poly(Fluorostyrene-Co-Bromostyrene) Blends, William Macknight, R. Vukovic, G. Bogdanic, Vjera Kuresevic, F. E. Karasz

William MacKnight

Copolymers of or tho (para )fluorostyrene and ortho(para )bromostyrene with a range of copolymer compositions were prepared by free radical polymerization in toluene solution using azobis­(isobutyronitrile). The miscibility and phase behaviour of these copolymers in blends with poly(2,6-dimethyl-l,4-phenylene oxide) (PPO) have been studied by differential scanning calorimetry. Of the four possible copolymer systems, miscibility was observed only for PPO/poly(o-fluorostyrene­co-p-bromostyrene) blends in which the copolymer contains between 11 and 73 mo!% p-bromostyrene. High temperature phase separation in the miscible blends is a function of copolymer composition and of the thermal history. The results can be explained on the basis of the …

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The Effect Of Chain Microstructure On Polymer- Polymer Miscibility, William Macknight, A. C. Balazs, F. E. Karasz Dec 1986

The Effect Of Chain Microstructure On Polymer- Polymer Miscibility, William Macknight, A. C. Balazs, F. E. Karasz

William MacKnight

A mean field model for the miscibility of binary polymer 
systems containing random copolymers has been extended to take 
into account the microstructure of the respective macromolecular constituents. The resulting model has been applied to the special 
case of mixtures of copolymers containing identical moieties but differing in microstructure and or composition. An example of 
such a system is the mixture of polyvinyl chloride and chlorinated polyethylene. 

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Miscibility And Volume Changes Of Mixing In The Polystyrene/Poly(2-Chlorostyrene) Blend System, William Macknight, Yoshiharu Tsujita, Keiko Iwakiri, Takatoshi Kinoshita, Akira Takizawa Dec 1986

Miscibility And Volume Changes Of Mixing In The Polystyrene/Poly(2-Chlorostyrene) Blend System, William Macknight, Yoshiharu Tsujita, Keiko Iwakiri, Takatoshi Kinoshita, Akira Takizawa

William MacKnight

No abstract provided.

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Poly(Ethylene Oxide)/ Poly(Methyl Methacrylate) Blends: Influence Of Tacticity Of Poly(Methyl Methacrylate) On Blend Structure And Miscibility, William Macknight, C. Silvestre, S. Cimmino, E. Martuscelli, F. E. Karasz Dec 1986

Poly(Ethylene Oxide)/ Poly(Methyl Methacrylate) Blends: Influence Of Tacticity Of Poly(Methyl Methacrylate) On Blend Structure And Miscibility, William Macknight, C. Silvestre, S. Cimmino, E. Martuscelli, F. E. Karasz

William MacKnight

No abstract provided.

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Effect Of Sequence Distribution On The Miscibility Of Polymer/Copolymer Blends, William Macknight, Anna C. Balazs, Isaac C. Sanchez, Irving Epstein, F. E. Karasz Dec 1984

Effect Of Sequence Distribution On The Miscibility Of Polymer/Copolymer Blends, William Macknight, Anna C. Balazs, Isaac C. Sanchez, Irving Epstein, F. E. Karasz

William MacKnight

Previous theories describing the phase behavior of copolymer blends have ignored the sequence distribution of monomer unit.a in the copolymer. We introduce a parameter, 8, that describes the binary sequence distribution of the monomers in a copolymer chain. By varying 8, we can describe a block, random, or alternating copolymer. It is assumed that the interaction energy between a monomer of homopolymer C and the monomer A (or B) in the copolymer AB is mediated by the nearest neighbors chemically bonded to the A (or B) structural 
unit. It is found that the sequence distribution may significantly affect the degree …

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Stereoregular Poly(Alkyl Methacrylate)S: Polymer-Polymer And Copolymer-Polymer Blends, William Macknight, J. A. Schroeder, F. E. Karasz Dec 1984

Stereoregular Poly(Alkyl Methacrylate)S: Polymer-Polymer And Copolymer-Polymer Blends, William Macknight, J. A. Schroeder, F. E. Karasz

William MacKnight

No abstract provided.

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Copolymer/Copolymer Blends: Effect Of Sequence Distribution On Miscibility, William Macknight, A. C. Balazs, I. C. Sanchez, Irving Epstein, F. E. Karasz Dec 1984

Copolymer/Copolymer Blends: Effect Of Sequence Distribution On Miscibility, William Macknight, A. C. Balazs, I. C. Sanchez, Irving Epstein, F. E. Karasz

William MacKnight

No abstract provided.

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