Estimation of interaction energies by the critical molecular weight method: 2. Blends with polysulfones

Abstract

SYNOPSISThe interaction energies between PS, Pa-MS, and PMMA, as well as acrylonitrile and maleic anhydride units, with a series of polysulfones were quantitatively determined from oligomer/oligomer, oligomer/ homopolymer, and homopolymer/copolymer blends. Interaction energies were calculated from the Flory-Huggins theory and the Sanchez-Lacombe equation of state theory using experimental cloud points or miscibility boundaries. Alkyl addition to the phenyl rings of polysulfone is favorable for miscibility with polystyrene whereas halogenation of the bisphenol connector unit favors miscibility with poly (methyl methacrylate). Interaction energies are quantitatively ranked and described qualitatively in terms of changes in the electronic charge distribution of the polymer repeat units as calculated by SYBYL software. 0 1994 John Wiley & Sons, Inc. Keywords: polysulfones styrene methyl methacrylate a-methyl styrene acrylonitrile blends interaction energies * Current address: The Dow Chemical Co., Midland, MI 48674. a Comments: 1. Pure component TB)s are too similar to be resolved. 2. Appearance depends on temperature. 3. Shows LCST behavior hut not at equilibrium. 4. Blend shows partial miscibility. 5. T, behavior depends on first or second heat to 250°C in DSC. 6. Appearance depends on composition. 7. T, behavior depends on first or second heat to 300°C in DSC. 8. T, behavior depends on first or second heat to 200°C in DSC. 9. Blends become cloudy once above T,.

A molecular dynamics simulation study of three polysulfones in dry and hydrated states

“…In a first step, polysulfone chains are generated by PMC–MD single‐chain sampling at temperatures corresponding to melt conditions (550 K for PESU and PPSU, and 500 K for PSU), i.e., slightly above their experimental glass transition temperature (∼497 K for PESU15, 63, 199–207 and PPSU,201, 204, 208 and ∼459 K for PSU 9, 15, 16, 63, 163, 199, 204–212. Then, in a second step, 20 uncorrelated chains are randomly reorientated and distributed in a periodic cubic MD box at an initial density close to the experimental values which are ∼1.37 ± 0.01 g cm −3 for PESU,197, 199, 201, 204, 206, 207 ∼1.291 ± 0.001 g cm −3 for PPSU,204, 209 and ∼1.238 ± 0.001 g cm −3 for PSU 9, 29, 197, 204, 206, 207, 209–215. To avoid unphysical spearings and interlockings216 during the introduction of excluded volume, a « phantom » atom is briefly placed at the centre of mass of each six‐atom ring 175.…”

Investigation into stress recovery behavior of shape memory polyurethane fiber

“…Likely, in our cold‐drawn programing process, soft segments are stretched first. Since room temperature is within the mixed phase transition region and well below the phase demixing temperature, the flexibility, and mobility of the soft segments are thus hindered by the short hard segments around them . Therefore, to reach the overall elongation, the hard segments in the mixed phase also need to be stretched and oriented.…”

“…Since room temperature is within the mixed phase transition region and well below the phase demixing temperature, the flexibility, and mobility of the soft segments are thus hindered by the short hard segments around them. [67][68][69][70][71] Therefore, to reach the overall elongation, the hard segments in the mixed phase also need to be stretched and oriented. As a result, the morphology for RT-2 is still in the state of Figure 6(a), however, with a much higher orientation in the mixed phase.…”

Polymers Containing Sulfur, Polysulfones

“…These are, in general, other engineering thermoplastics such as polycarbonates, some polyester, polyimides (qv), polyaryletherketones, and poly(phenylene sulfide) (PPS). Polymer blends involving polysulfones are discussed in numerous patents and journal articles, eg, a study (35) dealing with the interaction energies of polysulfones with several polymers as they relate to miscibility. Properties of PSF-PPS blends are well documented (36,37).…”