X-ray detectors for structure investigations constructed at JINR

J of Applied Polymer Sci

et al. 2006

More than 25 PP/PS/SEP blends, where PP is isotactic polypropylene, PS is atactic polystyrene, and SEP is poly(styrene-block-ethylene-co-propylene), were prepared. The main objective of this study was to investigate the influence of PP/PS viscosity ratio, TM , on the blends' morphology. It was shown that TM strongly influenced not only the overall morphology of the blends, but also the morphology of SEP, which exhibited as many as five different types of structure when blended with PP and/or PS. SEP was found an efficient compatibilizer of PP/PS blends as it decreased the average particle size in all studied systems. An interesting "by-product" of this work was the discovery of a brand-new type of polymer morphology, which was called morel structure. The characteristic feature of the morel structure was PS matrix compartmentalized by SEP.

Section: Methodsmentioning

confidence: 99%

Compatibilized iPP/aPS blends: The effect of the viscosity ratio of the components on the blends morphology

Šlouf

Radonjič

J of Applied Polymer Sci

et al. 2006

“…SAXS measurements were performed with a reconstructed Kratky camera with a 60‐μm entrance slit and a 42‐cm flight path. The used Ni‐filtered Cu Kα radiation [wavelength (λ) = 1.54 Å] was recorded with a position‐sensitive detector31 (Joint Institute for Nuclear Research, Dubna, Russia), for which the spatial resolution was approximately 0.1 mm. The intensities were taken in the range of the scattering vector ( q ) of (4π/λ) sin Θ from 0.006 to 0.2 Å −1 (where 2Θ is the scattering angle).…”

Section: Methodsmentioning

confidence: 99%

Compatibilization efficiency of styrene–butadiene triblock copolymers in polystyrene–polypropylene blends with varying compositions

J of Applied Polymer Sci

Hromádková

Fortelný

et al. 2004

ABSTRACT:The compatibilization efficiency of two styrene-butadiene-styrene triblock copolymers with short (SB1) and long (SB2) styrene blocks was studied in polystyrene (PS)-polypropylene (PP) blends of composition 20, 50, and 80 wt % PS. The supramolecular structure of the blends was determined by small-angle X-ray scattering, and the morphology was studied with transmission electron microscopy and scanning electron microscopy. Structural changes in both the uncompatibilized and compatibilized blends were correlated with the values of tensile impact strength of these blends. Even though the compatibilization mechanisms were different in blends with SB1 and SB2, the addition of the block copolymers to the PS-PP 4/1 and PS-PP 1/4 blends led to similar structures and improved the mechanical properties in the same way. These block copolymers had a very slight effect on the impact strength in PS-PP 1/1 blends, exhibiting a nearly cocontinuous phase morphology. The strong migration of SB2 copolymers to the interface and of SB1 copolymers away from the interface were detected during the annealing of compatibilized PS-PP 4/1 blends. ©

“…SAXS measurements were performed with an upgraded Kratky camera with a 60‐μm entrance slit and a 42‐cm flight path. Ni‐filtered Cu Kα radiation (wavelength λ = 1.54 Å) was used and registered with a position‐sensitive detector27 (Joint Institute for Nuclear Research, Dubna, Russia), of which the spatial resolution was approximately 0.15 mm. The intensities were taken in the scattering vector [ q = (4π/λ) sin θ, where 2θ is the scattering angle] range of 0.006–0.2 Å −1 .…”

Section: Methodsmentioning

confidence: 99%

Effect of mixing conditions on the morphology and properties of polystyrene/polyethylene blends compatibilized with styrene–butadiene block copolymers

Fortelný

J Polym Sci B Polym Phys

Mikešová

et al. 2003

The effect of mixing conditions on the morphology, molten-state viscoelastic properties, and tensile impact strength of polystyrene/polyethylene (80/20) blends compatibilized with styrene-butadiene block copolymers containing various numbers and lengths of blocks was studied. Under all mixing conditions, an admixture of a styrenebutadiene block copolymer led to a finer phase structure and to an increase in the dynamic viscosity, storage modulus, and tensile impact strength. The effects were stronger for S-B diblock with a short styrene block than for S-B-S-B-S pentablock with long styrene blocks (where S represents styrene and B represents butadiene). For all blends mixed longer than 2 min, the mixing time had only a small effect on their morphology and properties. Surprisingly, the localization of S-B diblock copolymers was strongly dependent on the rate of mixing. The mixing rate had a nonnegligible effect on the viscoelastic properties of the compatibilized blends.