Polymer Engineering and Science articles from November 2008

Polymer Engineering and Science archives from November 2008

Challenges of shape memory polymers: a review of the progress toward overcoming SMP's limitations.(shape memory polymers)(Technical report)
November 1, 2008... INTRODUCTION Smart materials encompass a wide variety of materials that are able to respond to specific stimuli (1). Shape memory polymers (SMPs) are one class of smart materials that have attracted tremendous attention, especially in the...

Electrical conductivity and rheological behavior of multiphase polymer composites containing conducting carbon black.(Technical report)
November 1, 2008... INTRODUCTION Conductive polymer composites (CPCs) exhibit a series of unique features, such as comparatively low room temperature resistivity, a percolation phenomenon, resistivity sensitivity to temperature, pressure and gas, and a...

Morphology and mechanical properties of impact modified polypropylene blends.
November 1, 2008... INTRODUCTION A major focus of scientists and engineers over the last several decades has been to increase the impact strength and therefore reduce the brittleness of materials. By altering and adding energy-absorption mechanisms, brittle...

Correlation of the melt rheological properties with the foaming behavior of immiscible blends of poly(2,6-dimethyl-1,4-phenylene ether) and poly(styrene-co-acrylonitrile).(Technical report)
November 1, 2008... INTRODUCTION Over the last decades, polymer blending has evolved into a well-developed technology for equipping materials with a set of desired properties (1), (2). The achieved scientific understanding, the technological progress as well...

Morphology and rheological properties of blends of chemically modified thermoplastic starch and polycaprolactone.(Technical report)
November 1, 2008... INTRODUCTION Interest in biobased and biodegradable polymers is increasing, due to concerns about managing carbon emissions in a sustainable manner, and the environmental requirements for the safe and effective disposal of polymers (like...

Injection molding of a diffractive optical element.(Technical report)
November 1, 2008... INTRODUCTION In his visionary talk "There's plenty of room at the bottom" given in 1959 at Caltech, Richard Feynman suggested plastic materials as ideal candidates for rapid replication of parts with micro- and nanosized features (1)....

Effect of processing parameters on the uniformity of adhesive meltblown web.(Technical report)
November 1, 2008... INTRODUCTION Because of the ability to produce a nonwoven web with the polymer as the starting material, the melt-blowing technology has been studied by many researchers for producing good quality meltblown webs or developing new products...

Film insert molding as a novel weld-line inhibition and strengthening technique.(Technical report)
November 1, 2008... INTRODUCTION The formation of weld lines, especially in multiple-gate injection molded parts or sections that contain holes or hollow regions, is usually unaviodable though largely undesirable. These region are less resistant to external...

A simplified method to determine the 3D orientation of an injection molded fiber-filled polymer.(Technical report)
November 1, 2008... INTRODUCTION In short-fiber reinforces composites, it is widely accepted that the microtexture plays an important role on their overall physical microtextural parameters (such as fiber volume fraction, aspect ratio, or distribution), the...

The development and characterization of polymer microinjection molded gratings.(Technical report)
November 1, 2008... INTRODUCTION A diffraction grating (DG) is a passive optical component that diffracts polychromatic light into its component wavelengths or monochromatic light into surfaces of constant phase, Fig. 1a. There are several types of...

Analysis of electrical, dielectric, and electromagnetic interference shielding behavior of graphite filled high density polyethylene composites.(Technical report)
November 1, 2008... INTRODUCTION Conducting polymer composites can be prepared by adding conducting fillers to the insulating polymers. Conducting filler may be carbon black (1-4), carbon fiber (5), (6), graphite powder (7-10), metal powder (11), (12), and...

Modeling of heat transfer in rotational molding.(Technical report)
November 1, 2008... INTRODUCTION Rotational molding, also known as rotocasting or rotomolding, is a process used for manufacturing hollow plastic products such as automotive parts, chemical and water tanks, tool boxes, canoes, kayaks, ducts, toys, backyard...

Multiobjective optimization of an industrial nylon-6 semi batch reactor using the a-jumping gene adaptations of genetic algorithm and simulated annealing.(Technical report)
November 1, 2008... INTRODUCTION An important requirement in any polymer industry is to produce polymer having the desired physical properties (quality). These properties depend mainly on the average molecular weight, molecular weight distribution, and the...

Mixed--mode subcritical crack growth in orthotropic polymers.(Technical report)
November 1, 2008... INTRODUCTION Multilayered polymers are useful in applications for which a single material cannot provide the required material properties. For example, for heat transfer applications, it may be desirable to consider a multilayer structure...

Smart sunglasses based on electrochromic polymers.(Technical report)
November 1, 2008... INTRODUCTION The concept of sunglasses appeared in the early 20th century and was first invented by Sam Foster in the 1920s. They serve many purposes in life. Today people know more and more about the sun's harmful effects on the eyes....

Mathematical modeling for the ionic inclusion process inside conducting polymer-based thin-films.(Technical report)
November 1, 2008... INTRODUCTION Currently, increasing applications of conducting poly rners (CP) such as bioclcctronic devices, drug delivery systems enhance the scope of investigating underlying phenomena of microcleclrode and nanoelcctrode processes (1),...

Effects of polyol molecular weight on properties of benzoxazine-urethane polymer alloys.(Technical report)
November 1, 2008... INTRODUCTION Polybenzoxazine is a novel class of thermosetting polymer which has various outstanding properties such as high thermal stability, easy processability because of its low melt viscosity, low water absorption, near zero...

Antistatic performance and morphological observation of ternary blends of poly(ethylene terephthalate), poly(ether esteramide), and lonomers.(Technical report)
November 1, 2008... INTRODUCTION Polymers such as polyesters and polymides are widely used in various fields such as packaging materials, electrical/electronic parts, and automative parts. However, the static charge that easily builds up on such molded parts...

Polydomain model predictions of molecular orientation in isothermal channel flows of thermotropic liquid crystalline polymers.(Technical report)
November 1, 2008... INTRODUCTION Liquid crystalline polymers (LCPs) have attracted significant attention as high strength/light weight structural materials (1). The excellent mechanical properties of LCPs are intimately related to the spontaneous ordering of...

Spatial heterogeneity of photo-oxidation and its relation with crack propagation in polyethylene composites.(Technical report)
November 1, 2008... INTRODUCTION Both natural weathering and artificially accelerated aging of polyethylene have been investigated for decades. From the literature, it is evident that both environmental factors and additives such as light stabilizers or...

HDPE functionalization via high shear stress-induced initiation and its effects on HDPE/GF composite.(high density polyethylene)
November 1, 2008... INTRODUCTION Copolymers have been widely used for the compatibilization of immiscible polymer blends as well as the improvement of interfacial adhesion in polymeric composites. In comparison with traditional copolymerization processes, the...

Erratum.(Correction notice)
November 1, 2008... Erratum to "A New Application of Biosurfactant for the Preparation of Polycaprolactone/Layered Silicate Nanocomposites" by Hsin-Tzu Liao, published in POLYM. ENG. SCI., 48: 1524-1531, 2008. DOI: 10.1002/pen.21124 The Affiliation for Prof....