Polymer Engineering and Science articles from June 2003

Polymer Engineering and Science archives from June 2003

Free-radical solution polymerization of styrene in a tubular reactor--effects of recycling.
June 1, 2003... The styrene free-radical solution polymerization reaction in a tubular loop reactor is studied here both experimentally and through simulation. An attempt is made to compare the performances of tubular loop reactors when the recycle ratio is...

An experimental study of morphology and rheology of ternary Pglass-PS-LDPE hybrids.
June 1, 2003... Ternary blends of low-density polyethylene (LDPE), polystyrene (PS), and a low Un-based phosphate glass (Pglass) were prepared at compositions ranging from 0-50 vol% Pglass in which either LDPE or PS was the continuous matrix phase....

Micromechanical behavior of impact modified poly(ethylene terephthalate).
June 1, 2003... The micromechanical behavior of poly(ethylene terephthalate), PET, modified with a metallocene polyolefin copolymer (mPE) was investigated. Uniaxial deformation tests were performed using a tensile stage in a scanning electron microscope. This...

Effect of die temperature on the morphology of microcellular foams.
June 1, 2003... A study on the extrusion of microcellular polystyrene foams at different foaming temperatures was carried out using [CO.sub.2] as the foaming agent. The contraction flow in the extrusion die was simulated with FLUENT computational fluid...

Study on the phase behavior of EVA/PS blends during in situ polymerization.
June 1, 2003... A triangular phase diagram of the polystyrene/styrene/ethylene-vinyl-acetate (PS/SM/EVA) system is established to account for the phase change during polymerization of SM. The phase behaviors for EVA and PS domains in the SM polymerization...

Synthesis and characterization of new aromatic polyimides containing well-defined conjugation units.
June 1, 2003... A series of aromatic polyimides composed of well-defined conjugation units were synthesized from 5.5'-bis(4-aminophenyl)-2,2'-bifuryl (PFDA) and 2,2'-bis(furyl) benzidine (FurylBZ) with various dianhydrides. The synthesized polyimides emit...

Probe segregation and [T.sub.g] determination of a supported ultra-thin polystyrene film studied by X-ray and neutron reflectivity, and SIMS.
June 1, 2003... Selective deuteration combined with X-ray and neutron reflectivity has been used to determine the extent of probe segregation to an interface in ultra-thin polymer films as a function of the number of thermal cycles. The extent of probe...

Starch-filled ternary polymer composites. I: dynamic mechanical properties.
June 1, 2003... INTRODUCTION The dynamic mechanical properties of starch-filled blends of polyethylene (PE) and poly(hydroxy ester ether) (PHEE) are strongly dependent on the properties and distribution of the minor component (PHEE). The effect of the...

Extrusion of polystyrene nanocomposite foams with supercritical [CO.sup.2].
June 1, 2003... Intercalated and exfoliated polystyrene/nano-clay composites were prepared by mechanical blending and in situ polymerization respectively. The composites were then foamed by using [CO.sub.2] as the foaming agent in an extrusion foaming process....

Reactive Melt Modification of Polypropylene With a crosslinkable Polyester.
June 1, 2003... Melt blending of polypropylene (PP) with a low molecular weight (MW) crosslinkable unsaturated polyester (UP) was studied in a batch mixer and a twin-screw extruder in the presence of peroxide (POX) free radical initiator. Competing degradation...

TOF-SIMS study of injection-molded polystyrene.
June 1, 2003... The purpose of this study was to provide experimental evidence of the separation of the polymer components at different scales during conventional processing. This was achieved by characterizing the surface and the bulk (cross section) of...

Morphology and properties of PBT/Nylon 6/EVA-g-MAH ternary blends prepared by reactive extrusion **.
June 1, 2003... Morphology and properties of poly(butylene terephthalate) (PBT)/nylon 6 (PA6)/EVA-g-MAH ternary blends were investigated. The blends were prepared in a co-rotating, intermeshing, twin-screw extruder. The incorporation of maleic anhyride (MAH)...

Preparation and properties of polyethylene-clay hybrids.
June 1, 2003... Polyethylene-clay hybrids have been prepared successfully by melt compounding with maleic anhydride grafted polyethylene (MA-g-PE), organophilic clay and polyethylene. In these polyethylene-clay hybrids, the silicate layers of the clay were...

Production, properties and impact toughness of die-drawn toughened polypropylenes.
June 1, 2003... We report the solid-state die-drawing of polypropylene and blends of polypropylene with a polyethylene elastomer to produce highly oriented products with enhanced mechanical properties. The blends showed an improvement in the drawability...

Effect of dissolved gas on the viscosity of HIPS in the manufacture of microcellular plastics.
June 1, 2003... Ha, Young-Wook The microcellular plastics (MCPs) process is a foaming process that has been developed to reduce the weight of a product without significant changes to the mechanical properties. To apply microcellular plastics to mass...