Polymer Engineering and Science articles from August 2004

Polymer Engineering and Science archives from August 2004

Structure and mechanical properties of polyamide-6,6/poly(ethylene terephthalate) blends.
August 1, 2004... INTRODUCTION Polymer blending is widely recognized as the most common method for developing new polymeric materials. One of its main advantages is that it permits tailoring the properties of the final product by changing the blend...

Numerical investigation of the influence of material properties and adhesive layer thickness on the heating efficiency of microwave curing of an adhesive-bonded joint.
August 1, 2004... INTRODUCTION Adhesive bonding is an effective joining technique for producing useful structural and non-structural assemblies (1). Various types of adhesives are extensively used in different industries. For each type of adhesive,...

Thermal properties of biaxially deformed in situ composites.
August 1, 2004... INTRODUCTION Over the past 30 years, the ever-increasing demand for high-performance polymer products has created a surge of interest in developing polymer blends. One area of interest is the use of thermotropic liquid crystalline polymers...

Rheological, mechanical and biodegradation studies on blends of thermoplastic starch and polycaprolactone.
August 1, 2004... INTRODUCTION Interest in biodegradable polymer blends and composites is increasing because of environmental requirements for safe and effective disposal of polymers (like plastics) after use. Since Griffin (1) prepared starchfilled...

Indentation of poly(formaldehyde), reinforced nylons and poly(ethyl terephthalate).
August 1, 2004... INTRODUCTION The determination of mechanical properties such as strength and stiffness from the indentation behavior obtained by the penetration of a sharp indenter into the surface of a material has become a method of increasing interest...

Mechanical and erosion properties of CaC[O.sub.3]-EMAA thermal sprayed coatings.
August 1, 2004... INTRODUCTION Polymers are relatively versatile materials in terms of their processing and production. One processing technique that is increasingly being used is that of thermal spray. While this has been performed for some time with...

Modeling and simulation of stretch blow molding of polyethylene terephthalate.
August 1, 2004... INTRODUCTION Because of its excellent properties, polyethylene terephthalate (PET) is used extensively in the food packaging industry, particularly for the production of soft drink bottles using the injection stretch blow molding process,...

Development and characterization of reactively extruded PVC/polystyrene blends.
August 1, 2004... INTRODUCTION Recent decades have seen an increasing demand for new polymeric materials. By blending, new materials can be developed that combine physical and mechanical properties of their components, depending on the composition and level...

Online measurements of crystallinity using Raman spectroscopy during blown film extrusion of a linear low-density polyethylene.
August 1, 2004... INTRODUCTION The tubular blown film process is an important technique for producing polymeric films that has received significant attention from both modeling (1-5) and experimental perspectives (6-9). A detailed analysis of various...

Kinetic and thermodynamic considerations in the synthesis of a new three-arm poly([epsilon]-caprolactone).
August 1, 2004... INTRODUCTION In recent years there has been mounting interest in the use of "environmentally friendly" polymer materials that are biodegradable, recyclable, or derived from annually renewable resources. The rationale for utilization of...

An axisymmetric model for thread forming in polycarbonate and polypropylene screw and boss fasteners.
August 1, 2004... INTRODUCTION One of the most popular ways of fastening assemblies together is by means of the boss and screw, an example of which is shown in Fig. 1. The threads of the boss may be pre-tapped, cut by a thread-cutting screw, or formed by a...

Effect of ultrasound on extrusion of PP/EPDM blends: structure and mechanical properties.
August 1, 2004... INTRODUCTION Isotactic polypropylene (iPP) is used in a wide range of applications because of its attractive properties of relative high stiffness, heat distortion temperature, and its low price. However, the impact toughness of iPP is...

Determination of the phase transition behavior of thermoplastic polyurethanes from coupled rheology/DSC measurements.
August 1, 2004... INTRODUCTION Thermoplastic polyurethanes (TPUs) are AB-type copolymers of alternating soft and hard segments. The soft segments, consisting of long polymeric chains of a macro-glycol (polyether or polyester type), are flexible and weakly...

The thermomechanical environment and the mechanical properties of injection moldings.
August 1, 2004... BACKGROUND It has long been recognized that the mechanical behavior of an injection molded semicrystalline polymer is influenced by the processing method and conditions used to manufacture it. However, the establishment of direct...

Investigation of morphology formation in SBS block copolymer/homopolystyrene blends.
August 1, 2004... INTRODUCTION The field of polymer blends has seen vast growth in both its scientific basis and its technological and commercial development. The principal motivation is to enhance the desired properties of the individual homopolymers or...

The effect of surface energy of boron nitride on polymer processability.
August 1, 2004... INTRODUCTION Although the development of catalysts such as metallocenes has made the synthesis of polyolefins easier and improved their mechanical properties, the processing of these improved polyolefins has become more challenging for...

Relationship between cell morphology and impact strength of microcellular foamed high-density polyethylene/polypropylene blends.
August 1, 2004... INTRODUCTION Containers and packaging are the largest category of plastics in municipal solid waste. Recycling reduces the impact of this waste on limited landfill space. Polyolefins, including high-density polyethylene (HDPE) and...

Deformation and morphology development of poly(ethylene terephthalate)/polyethylene and polycarbonate/polyethylene blends with high interfacial contact during elongation.
August 1, 2004... INTRODUCTION Thermoplastic engineering polymers like polycarbonate (PC), polyamide (PA) and thermoplastic polyester generally exhibit excellent mechanical properties, dimensional stability and heat resistance. They play very important...

Capacitive transducer for in-mold monitoring of injection molding.
August 1, 2004... INTRODUCTION The measurement and/or monitoring of polymer melt status inside an injection mold, particularly the melt-front velocity and melt-front position during the filling stage, is important to the understanding and mold design of...

Recycled poly(ethylene terephthalate) chain extension by a reactive extrusion process.
August 1, 2004... INTRODUCTION Post-consumer PET undergoes a reduction in intrinsic viscosity, [[eta]], when recycled in a normal extrusion system. The occurrence of thermal and hydrolytic degradation reactions during recycled PET melt processing is...

Injection molded automotive TPO--a multilayer composite structure of varied orientations.
August 1, 2004... INTRODUCTION Structure-property relationships are extensively studied by polymer engineers. While it is generally agreed that the properties of an injection molded part partially depend on its morphology, often the microstructure of a part...

Analysis of the creep behavior of polypropylene-woodflour composites.
August 1, 2004... INTRODUCTION The use of natural fibers as reinforcement of polymeric matrices has attained great academic and commercial interest in the past decade owing to the low cost, large availability and biodegradability of the fibers. Wood fibers...