Polymer Engineering and Science articles from September 2006

Polymer Engineering and Science archives from September 2006

Mechanical properties of recycled polyethylene ecocomposites filled with natural organic fillers.
September 1, 2006... INTRODUCTION Polymer composites have been subject to increasing interest, study, and utilization for some decades. One of the main categories of polymer composites is represented by polymers filled with glass fibers, which fit to a number...

Effects of molding conditions on transcription molding of microscale prism patterns using ultra-high-speed injection molding.
September 1, 2006... INTRODUCTION Over the past few years, the transcription of micro- or nanostructures of polymers has been conducted extensively, with increasing applications of polymer materials in IT and biotechnologies. Mainly, two manufacturing...

Amphiphilic block copolymers of PtBA-b-PMMA as compatibilizers for blends of PET and PMMA.(polyethylene terephthalate)(polymethyl methacrylate)
September 1, 2006... INTRODUCTION The commercial significance of poly(ethylene terephthalate), PET, and poly(methyl methacrylate), PMMA, are well known and confirmed by a large number of producers throughout the world. In particular, PET is an extensively used...

Synthesis of exfoliated PP/LDH nanocomposites via melt-intercalation: structure, thermal properties, and photo-oxidative behavior in comparison with PP/MMT nanocomposites.(polypropylene)(montmorillonites)
September 1, 2006... INTRODUCTION The very large commercial importance of polypropylene (PP) has been driving an intense investigation of PP/layered inorganic filler nanocomposites. These nanocomposites reinforced by layered inorganic fillers were endowed with...

Dynamic nanoindentation of some polyolefins.
September 1, 2006... INTRODUCTION The traditional method to test the hardness of a material involves loading a hard indenter against the material under scrutiny. If the load is large enough, plastic deformation occurs and the extent of this is a measure of the...

Interrelationships between welding parameters of hot-gas welded polypropylene.
September 1, 2006... INTRODUCTION Joints in plastic structures can be classified according to the physical principles of joining: one may distinguish among joints held together by force, shape, or material. The latter category--owing to the rapid development...

Biaxial orientation in LLDPE films: comparison of infrared spectroscopy, X-ray pole figures, and birefringence techniques.(linear low-density polyethylene)
September 1, 2006... INTRODUCTION Semicrystalline polyolefin films represent a large segment of the plastics industry. The most widely used biaxial processes for films are the standard film blowing process (for various polyethylenes, PE), double bubble process...

Importance of elongational properties of polymer melts for film blowing and thermoforming.
September 1, 2006... INTRODUCTION Film blowing and thermoforming are important industrial processing operations, which are strongly dominated by empirical knowledge. This is mainly due to the pronounced elongational flow occurring in both processes and the...

Preparation and characterization of thermoplastic polyurethane elastomer and polyamide 6 blends by in situ anionic ring-opening polymerization of [epsilon]-caprolactam.
September 1, 2006... INTRODUCTION The primary motivation for blending immiscible polymers is to create materials with combinations of properties superior to the individuals [1, 2]. It has been known that the ultimate properties of such blends depend very much...

Surface tearing and wall slip phenomena in extrusion of highly filled HDPE/wood flour composites.
September 1, 2006... INTRODUCTION Wood plastic composites (WPC) have simultaneously attracted research in both plastics and wood technology because wood fillers, namely chips, flakes, flour, and fibers represent low-cost renewable reinforcements that enhance...

Thermal and shear flow effects on microstructure of a thermotropic liquid crystalline polymer.
September 1, 2006... INTRODUCTION Thermotropic liquid crystalline polymer (TLCP) products are known to possess excellent mechanical properties and high dimensional precision even when processed by conventional techniques such as injection and rotational...

Single-polymer composites based on slowly crystallizing polymers.
September 1, 2006... INTRODUCTION The original concept of a single-polymer composite (SPC), a composite with matrix and reinforcement from the same polymer, was presented by Capiati and Porter [1] three decades ago. The method utilized the noticeable...

Free volume microprobe studies on Poly(methyl methacrylate)/Poly(vinyl chloride) and Poly(vinyl chloride)/Polystyrene blends.
September 1, 2006... INTRODUCTION Polymer blending is a widely used technique to improve the physical/mechanical properties of homopolymers [1]. Blending of two polymers may either result in a compatible (miscible) system or incompatible (immiscible) system....

Preparation of diblock copolymers consisting of methoxy poly(ethylene glycol) and poly ([epsilon]-caprolactone)/poly(L-lactide) and their degradation property.
September 1, 2006... INTRODUCTION One of the focuses of present pharmaceutical research is the development of new, biodegradable, nontoxic, reproducible, and well-characterized drug delivery carriers [1-3]. The critical point in the design of drug delivery...

Anisotropy in the electrical behavior of immiscible polypropylene/nylon/carbon black blends processed slightly below the melting temperature of the nylon.
September 1, 2006... INTRODUCTION Carbon black (CB) filled polymers have been extensively studied and used when moderate conductivity levels are required [1-3]. Recent studies focus on reducing the CB content while maintaining a relatively high conductivity,...

Three-dimensional numerical simulation of injection molding filling of optical lens and multiscale geometry using finite element method.
September 1, 2006... INTRODUCTION Injection molding has been an important manufacturing process for the mass production of complex plastic parts and accounts for one-third of all plastics processed. The quality and performance of injection molded parts depend...

Injection molding shrinkage of PP: experimental progress.(polymer processing)
September 1, 2006... INTRODUCTION Injection molding is a widespread polymer processing technique in which molten material is forced to flow into a closed cavity where it solidifies. The object obtained is approximately the shape of the mold and may not involve...

Anomalous rheological properties of polyethylene molecular composites.
September 1, 2006... INTRODUCTION The improvement of elastic properties in the molten state, such as the strain-hardening in the elongational viscosity, normal stress difference, and swell ratio, is one of the most important focus areas for linear polymers....

Compatibilized poly(ether imide)/amorphous polyamide blends by means of poly(ethylene terephthalate) addition.
September 1, 2006... INTRODUCTION Polymer blending has been a topic of great academic and industrial interest over recent decades as it offers combinations of properties often not available through nonblended polymers [1]. An extension of the number of blend...

Crystallization, morphology, and mechanical behavior of polylactide/poly([epsilon]-caprolactone) blends.
September 1, 2006... INTRODUCTION Polylactides are gaining attention in the medical field for application areas such as sutures, antibiotic release, and macroscopic temporary implants [1, 2]. Polylactide bioresorbable implants have advantages in repair and...

Isothermal and nonisothermal crystallization kinetics of poly([epsilon]-caprolactone)/multi-walled carbon nanotube composites.
September 1, 2006... INTRODUCTION Carbon nanotubes (CNTs), a new discovery of Iijima and Ichihashi [1], have received great interest for their potential use in probe tips for SPMs [2], field emitters [3], nanoelectronic devices [4, 5], and nanotube-based...

Curing behavior and structure of an epoxy/clay nanocomposite system.
September 1, 2006... INTRODUCTION A method to improve the physical properties of a polymer is the addition of reinforcing particles or fibers to the polymer to form composite materials. Owing to the development of high-strength and light-weight fibers, such as...

Gold coating of polyethylene modified by argon plasma discharge.
September 1, 2006... INTRODUCTION Metallization of polymers is essential for their applications in microelectronic and photonic devices, and medical implants [1-3]. However, the adhesion between metals and polymers is normally very poor, causing difficulties...