The Control Of The Melt Rheology And Physical Properties Of Polystyrene By Ionic Interaction,
2014
The University of Akron
The Control Of The Melt Rheology And Physical Properties Of Polystyrene By Ionic Interaction, Robert Weiss, P. K. Agarwal, R. D. Lundberg
Robert Weiss
No abstract provided.
Explanation Of;Dark-Streak&Light Scattering Patterns And Shear-Induced Structure Development Of Phase-Separated Polymer Blends,
2014
The University of Akron
Explanation Of;Dark-Streak&Light Scattering Patterns And Shear-Induced Structure Development Of Phase-Separated Polymer Blends, Robert Weiss
Robert Weiss
No abstract provided.
The Influence Of Intermolecular Interactions On The Melt Rheology Of A Propylene-Acrylic Acid Copolymer And Its Salts.,
2014
The University of Akron
The Influence Of Intermolecular Interactions On The Melt Rheology Of A Propylene-Acrylic Acid Copolymer And Its Salts., Robert Weiss
Robert Weiss
Ionomers based on propylene–acrylic acid copolymer have been prepared and their rheological behavior studied. With different cations the melt viscosity at any shear rate increases as tributylamine salt < acid < zinc salt < sodium salt. Similarly, the activation energies for viscous flow follow the order polypropylene ∼ tributylamine salt < acid ∼ zinc salt < sodium salt. These results are a consequence of intermolecular interactions between salt groups for the metal acrylate derivatives and hydrogen bonding for the acid derivatives. Strong ionic interactions are absent in the tributylamine salt because of steric hindrance of the bulky amine substituents. The glass transition temperatures for these …
Compatibilization Of Polymer Blends By Complexation: 1. Spectroscopic Characterization Of Interactions In Ionomer/Polyamide Blends,
2014
The University of Akron
Compatibilization Of Polymer Blends By Complexation: 1. Spectroscopic Characterization Of Interactions In Ionomer/Polyamide Blends, Yi Feng, Asher Schmidt, Robert Weiss
Robert Weiss
Electron paramagnetic resonance (EPR), Fourier transform infrared (FTIR), and solid-state 15N nuclear magnetic resonance (15N-NMR) spectroscopies were used to characterize the structure and relative strength of the interactions between metal sulfonate and amide groups in blends of lightly sulfonated polystyrene ionomers and an N-methylated polyamide, poly(N,N‘-dimethylethylene sebacamide), and low molecular weight model complexes. The metal sulfonate groups, which aggregate in the neat ionomer, were dispersed by the polyamide in the blend as a consequence of a complexation that involved the sulfonate cation and both the carbonyl oxygen and the amide nitrogen of the polyamide. The FTIR and 15N-NMR spectra were …
Flow-Induced Mixing Of Blends Of Poly(Ethylene-Vinyl Acetate) And Solution Chlorinated Polyethylene,
2014
The University of Akron
Flow-Induced Mixing Of Blends Of Poly(Ethylene-Vinyl Acetate) And Solution Chlorinated Polyethylene, I. Hindawi, J. S. Higgins, A. F. Galambos, Robert Weiss
Robert Weiss
See Link
Polymer Alloys, Blends And Ionomers: An Overview,
2014
The University of Akron
Polymer Alloys, Blends And Ionomers: An Overview, Robert Weiss
Robert Weiss
This chapter provides a broad overview of the subjects of polymer blends and ionomers. Specific topics concerning polymer blends include the thermodynamics of mixing of polymer-polymer pairs, polymer interfaces, rheology, and mechanical properties. For ionomers, the chemistry, structure, rheology and solution properties are discussed.
The Synthesis Of Sulfonated Polymers By Free Radical Copolymerization. (Poly(Butadiene-Co-Sodium Styrene Sulfonate).,
2014
The University of Akron
The Synthesis Of Sulfonated Polymers By Free Radical Copolymerization. (Poly(Butadiene-Co-Sodium Styrene Sulfonate)., Robert Weiss
Robert Weiss
The copolymerization of butadiene with sodium styrene sulfonate was studied and the copolymer products characterized. In general these copolymers contain 0.5–4 mole% of sulfonated monomer. The effects of the following reaction variables are described: emulsifier type and concentration, monomers feed ratio, chain transfer agent concentration, and reaction conversion. The products were heterogeneous with regard to composition, molecular weight, and solubility behavior. Copolymers prepared under certain conditions exhibited strong intermolecular interactions derived from associations of the ionic species as observed in other ionomers.
Improvement Of The Processability Of Poly(Ether Ketone Ketone) By The Addition Of A Liquid Crystalline Polymer,
2014
The University of Akron
Improvement Of The Processability Of Poly(Ether Ketone Ketone) By The Addition Of A Liquid Crystalline Polymer, Robert Weiss
Robert Weiss
The addition of a thermotropic liquid crystalline, wholly aromatic copolyester, TLCP, improved the melt processability of poly(ether ketone ketone), PEKK. The tensile strength and modulus of the blends also improved with increasing TLCP, but the elongation at break decreased significantly. The blends were phase-separated, but the polymers were partially miscible as evident from shifts of the glass transition temperature (Tg) of each component towards that of the other component in the blend. Similarly, the melting points (Tm) of both components were depressed by blending. When the crystallization temperature was above Tm of the TLCP, the PEKK crystallization rate in the …
Miscible Blends Of A Thermotropic Liquid Crystalline Polymer And Sulfonated Polystyrene Ionomers,
2014
The University of Akron
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 …
Electron Spin Resonance Studies Of Ionic Interactions In Sulfonated Polystyrene Manganese (Ii) Salts.,
2014
The University of Akron
Electron Spin Resonance Studies Of Ionic Interactions In Sulfonated Polystyrene Manganese (Ii) Salts., Robert Weiss
Robert Weiss
No abstract provided.
Observation Of Cluster Formation In An Ionomer,
2014
The University of Akron
Observation Of Cluster Formation In An Ionomer, Robert Weiss
Robert Weiss
No abstract provided.
A Small Angle Neutron Scattering Study Of A Semiflexible Main-Chain Liquid Crystalline Copolyester,
2014
The University of Akron
A Small Angle Neutron Scattering Study Of A Semiflexible Main-Chain Liquid Crystalline Copolyester, Robert Weiss
Robert Weiss
No abstract provided.
Synthesis, Properties, And Structure Of Sulfonate Ionomers,
2014
The University of Akron
Synthesis, Properties, And Structure Of Sulfonate Ionomers, Robert Weiss
Robert Weiss
The unique mechanical and rheological properties of ionomers are sources of growing academic and industrial interest. The relationship between the complex properties that ionomers exhibit and their microstructure has been the subject of numerous studies. A greater understanding of this relationship is necessary if one wishes to manipulate the ionic interactions in order to control the properties of the polymer.
Compatibilization Of Syndiotactic Polystyrene And A Thermotropic Liquid Crystalline Polymer Blend With A Zinc Salt Of A Sulfonated Polystyrene Ionomer,
2014
The University of Akron
Compatibilization Of Syndiotactic Polystyrene And A Thermotropic Liquid Crystalline Polymer Blend With A Zinc Salt Of A Sulfonated Polystyrene Ionomer, Robert Weiss
Robert Weiss
A zinc salt of a lightly sulfonated (4.5 mol %) polystyrene ionomer was used to compatibilize a 3/1 (w/w) blend of syndiotactic polystyrene and a wholly aromatic thermotropic liquid-crystalline polymer (TLCP). The addition of the ionomer significantly reduced the dispersed TLCP domain size and improved the tensile strength, ultimate elongation, and flexural toughness of the blend
Microstructure Of Block Copolymers Of Polystyrene And Poly(Ethylene-Alt-Propylene),
2014
The University of Akron
Microstructure Of Block Copolymers Of Polystyrene And Poly(Ethylene-Alt-Propylene), Robert Weiss
Robert Weiss
The microstructure and microphase behaviour of diblock (Ma ≈ 27 and 50 kg mol−1) and triblock (Ma ≈ 50kg mol−1) copolymers of polystyrene (PS) and poly(ethylene-alt-propylene) (PEP) were studied by small angle X-ray scattering (SAXS), transmission electron microscopy (TEM) and dynamic mechanical thermal analysis (DMTA). The composition was varied from 10 wt.% to 50 wt.% PS. The morphology of solution-cast and compression-moulded samples was compared. The common packing arrangements of body-centred-cubic (BCC) spheres, hexagonal-close-packed (HCP) cylinders and alternating lamellae were observed for the PS microdomains using SAXS and TEM. A microphase texture of PS spheres with a liquid-like packing (LLP) …
Analysis Of Caprolactam Polymerization,
2014
The University of Akron
Analysis Of Caprolactam Polymerization, Robert Weiss
Robert Weiss
No abstract provided.
Characterization Of The Block Microstructure In Block Copolymer Ionomers Using Small Angle X-Ray Scattering,
2014
The University of Akron
Characterization Of The Block Microstructure In Block Copolymer Ionomers Using Small Angle X-Ray Scattering, S. Mani, Robert Weiss, C. E. Williams, S. F. Hahn
Robert Weiss
The block microstructure of a series of diblock copolymer ionomers was investigated using synchrotron small-angle x-ray scattering (SAXS). The base materials used were poly[styrene-b-(ethylene/propylene)] (SEP) diblock copolymers with a constant total molecular weight of ca. 50 kg/mol, but three different compositions : 20.3 wt%, 35.6 wt% and 50.4 wt% polystyrene (PS). The polystyrene microphase structures for these unmodified diblock copolymers were cylindrical, lamellar and lamellar, respectively. Ionomers were synthesized from the block copolymers by lightly sulfonating the PS blocks, followed by neutralization to the sodium and zinc salts. The introduction of ionic species into the PS blocks perturbed the block …
The Development Of The Ionic Microphase In Sulfonated Poly(Ethylene-Co-Propylene-Co-Ethylidene Norbornene) Ionomers During Physical Aging,
2014
The University of Akron
The Development Of The Ionic Microphase In Sulfonated Poly(Ethylene-Co-Propylene-Co-Ethylidene Norbornene) Ionomers During Physical Aging, Robert Weiss
Robert Weiss
No abstract provided.
Comparisons Of Styrene Ionomers Prepared By Sulfonating Polystyrene And Copolymerizing Styrene With Styrene Sulfonate,
2014
The University of Akron
Comparisons Of Styrene Ionomers Prepared By Sulfonating Polystyrene And Copolymerizing Styrene With Styrene Sulfonate, Robert Weiss
Robert Weiss
As part of a continuing study of ion-containing polymers, a comparison has been made on styrene-based sulfonate ionomers obtained by two different processes. Copolymers of styrene with sodium styrene sulfonate (SSS) have been compared with corresponding polymers obtained by the sulfonation/neutralization of preformed polystyrene (S–PS). The former system covered a range of sulfonate level from 1 to 30 mol %, while the latter ranged from about 1 to 7 mol %. The characterization of these materials has been conducted using solubility behavior, dilute solution viscometry, thermal mechanical analysis, density measurements, and water adsorption studies. At low (ca. 1%) levels the …
Ftir Studies Of Ionic Interactions In Blends,
2014
The University of Akron
Ftir Studies Of Ionic Interactions In Blends, Robert Weiss
Robert Weiss
No abstract provided.
