Polymer Engineering and Science articles from December 2008

Polymer Engineering and Science archives from December 2008

Maleic anhydride/styrene melt grafting and crosslinking onto ethylene-octene copolymer.(Technical report)
December 1, 2008... INTRODUCTION Polyolefin elastomer (POE) is ethylene-octene copolymer developed using a metallocene catalyst by Dow Chemical. POE is characterized by narrow molecular weight distribution and homogeneous comonomer distribution. It has fast...

Crystal structure and orientation behavior of transversely compressed poly(ethylene-co-1-octene) filaments.(Technical report)
December 1, 2008... INTRODUCTION Polyethylene has become an important commercial thermoplastic, since its low density form (LDPE) was first produced in the 1930s by ICI (1). A high density linear form (HDPE) was synthesized in the 1950s by Ziegler et al....

A robust shock and noise model for the manufacturing of molded LDPE foams.(Technical report)
December 1, 2008... INTRODUCTION Plastic foams are made up of scattered cavities. These cavities enhance lightness and softness, while adding to the soundproofing and heatproofing qualities. Polymer foams are increasingly used in industrial applications. Made...

Characterizing the nonlinear viscoelastic properties of sealant, including its Mullins effect.(Technical report)
December 1, 2008... INTRODUCTION A cured sealant is an elastomer and displays two important characteristics common to many elastomers: a nonlinear viscoelastic response to mechanical deformation and the Mullins effect (1). The Mullins effect, which has been...

An optical investigation of high-tenacity polyester (H-T PET) fibers annealed at different temperatures.(Technical report)
December 1, 2008... INTRODUCTION Poly (ethylene terephthalate) PET is a semicrystalline polymer, of considerable commercial importance, having a wide variety of end uses in fibers, films, or bottle form. PET can be readily fabricated into fibers, whose...

Effect of crystallite size on the deformation and fracture of poly(vinylidene fluoride-trifluorethylene) ferroelectric copolymer films under uniaxial tension.(Technical report)
December 1, 2008... INTRODUCTION Polyvinylidene fluoride (P(VDF))-based ferroelectric polymers have recently attracted extensive attention because they have a great potential for applications in actuators, electromechanical and acoustic transducers,...

Modeling contraction flows and swell of polymer melts extruded from dies of various lengths.(Technical report)
December 1, 2008... INTRODUCTION The swell (or extrudate swell, or Barrus Effect) occurs when a polymer liquid discharged from a die/channel, experiences a free surface flow. The swell is commonly observed in many polymer processing operations, such as...

Melting behavior and isothermal crystallization kinetics of Nylon 11/EVOH/dicumyl peroxide blends.(Technical report)
December 1, 2008... INTRODUCTION In recent years, high barrier polymer blends have attracted much attention due to their prevention of the solvents permeation from plastic fuel tanks and agrochemical bottles, as such permeation resulted in pollution and...

The effects of spinning conditions on the morphology of electrospun jet and nonwoven membrane.(Technical report)
December 1, 2008... INTRODUCTION The electrospinning method has attracted a great deal of attention for its high efficiency of producing nonwoven nanofiber membrane. When compared with the other forms of nanofibers (e.g. carbon nanotubes), these fibers are...

Direct patterning of polystyrene-polymethyl methacrylate copolymer by means of laser interference lithography using UV laser irradiation.(Technical report)
December 1, 2008... INTRODUCTION The fabrication of functionalized surface of polymers is of relevant importance in chemistry, biology, physics, and material science. Examples of functional surfaces are micro/nano periodic arrays that can be fabricated using...

Preparation of nanocomposites based on PP and PA6 by direct injection molding.(polypropylene, polyamide 6 ()(Technical report)
December 1, 2008... INTRODUCTION Polymer layered silicate nanocomposites have unique properties that have rise to a remarkable interest since the 1950s, when they appeared for the first time (1). In montmorillonite (MMT), one of most used clay, which has...

Studies on epoxy blends modified with a hyperbranched polyester.(Technical report)
December 1, 2008... INTRODUCTION Epoxy resins are widely used due to their thermal. mechanical, chemical, and corrosion resistance. A favorable property of epoxy resins is the low viscosity in the uncured state that enables resins to be processed without the...

Control of morphology of sulfonated syndio-polystyrene membranes through constraints imposed by siloxane networks.(Technical report)
December 1, 2008... INTRODUCTION The main function of members in Fuel Cells is to transport protons from the anode to the cathode (1), (2). In the case of Polymer Electrolyte Membranes Fuel Cells (PEMFC), the proton conductivity paths are provided by means of...

Probing the viscoelastic properties of brominated isobutylene-co-p-methylstyrene rubber/tackifier blends using a rubber process analyzer.(Technical report)
December 1, 2008... INTRODUCTION Brominated isobutylene-co-p-methylstyrene (BIMS) rubber is a fairly new commercial rubber used in a number of industrial applications in both tire and nontire areas. In tire sector, BIMS elastomer has been highly evaluated in...

Use of carboxylated nitrile rubber and natural rubber blends as retreading compound for OTR tires.(Technical report)
December 1, 2008... INTRODUCTION Tires used in mining vehicles are very costly and need regular maintenance, because it is impossible to accept its replacement expense within very short term. The rugged working conditions in mining industries reduce the life...

Effect of thermomechanical history on the crystallization of poly(ether-block-amide).(Technical report)
December 1, 2008... INTRODUCTION Thermoplastic elastomers constitute an interesting class of materials. Such materials are typically composed of alternating, flexible soft and more rigid segments. By tuning the relative length of these segments during...

Study on flame retardance of co-microencapsulated ammonium polyphosphate and dipentaerythritol in olypropylene.(Technical report)
December 1, 2008... INTRODUCTION Intumescent flame retardant (IFR) additives originally used in fire-proof coatings have recently aroused a great attention in the flame retardation of plastics. In comparison with halogen-containing flame retardants, the IFR...

Study on the cell structure and compressive behavior of biodegradable poly([epsilon]-caprolactone) foam.(Technical report)
December 1, 2008... INTRODUCTION Foam materials have the advantage of low density, high specific strength, low heat conductivity, and good isolation to sound, making them find wide applications in market sectors such as construction, packaging, buoyancy,...

Property modulation of Poly(N-isopropylacrylamide) hydrogels by incorporation of modified silica.(Technical report)
December 1, 2008... INTRODUCTION Poly(N-isopropylacrylamide) (PNIPA), a well-known thermoresponsive polymer, exhibits a lower critical solution temperature (LCST) of 32-34[degrees]C in aqueous media (1). The cross-linked structure of PNIPA has characteristics...

Chemorheological characterization of thermosetting polyurethane formulations containing different chain extender contents.(Technical report)
December 1, 2008... INTRODUCTION The success in the processing of a reacting system necessitates a thorough understanding about the change in its rheological properties during reaction progression. The study of rheological changes occurring during the course...

Stretching-induced [beta]-crystal of iPP: influence of stretching ratio.(Technical report)
December 1, 2008... INTRODUCTION In most polymer processing operations, such as injection molding, film blowing, and fiber spinning and extrusion the molten polymer chains are subjected to intensive shear and stretching flow fields. Empirically and...

The effect of clay dispersion on the properties of LLDPE/LLDPE-g-MAH/montmorillonie nanocomposites.(linear low density polyethylene, maleic anhydridge)(Technical report)
December 1, 2008... INTRODUCTION Layered silicate-based polymer nanocomposites have attracted considerable interest because nanometric scale dispersion was obtained in polyamide/clay composites (1). When compared with conventional polymer composites, such...

Thermal conductivity of polymer nanocomposites made with carbon nanofibers.(Technical report)
December 1, 2008... INTRODUCTION Nanomaterials are increasingly being used as additives to polymers to simultaneously enhance a variety of properties without sacrificing any qualities of the base polymer. Carbon nanotubes (CNT) and carbon nanofibers (CNF),...

Interfacial slip-stick transition induced by reactive compatibilization in ethylene-co-butyl acrylate elastomer dispersed polyamide 6 blend subjected to high shear flow and extensional flow.(Technical report)
December 1, 2008... INTRODUCTION Melt blending of a semicrystalline polymer with an elastomer to design a material of desired impact properties has been extensively studied (1-5). In general, melt mixing of two polymers or polymer/elastomer leads to an...