SPE Library

The SPE Library contains thousands of papers, presentations, journal briefs and recorded webinars from the best minds in the Plastics Industry. Spanning almost two decades, this collection of published research and development work in polymer science and plastics technology is a wealth of knowledge and information for anyone involved in plastics.

The SPE Library is just one of the great benefits of being an SPE member! Are you taking advantage of all of your SPE Benefits?

Not an SPE member? Join today!

Use % to separate multiple keywords.

Search SPE Library

Conference Proceedings

Crush-Behavior of GMT-Products

Anton J. Heidweiller, May 2005

Compression tests were carried out on Glass Mat Reinforced Thermoplastics (GMT) panels applying three ratios for thickness over width. Some panels showed a typical ductile splaying collapse mode with gross plasticity. The specific energy absorption of these panels was very high, and even higher than was found in literature for crush cones of this material. Aim is to formulate design rules for products that are composed of flat plane elements and are loaded on impact.

The Effect of Cooling Regime on the Thermal, Mechanical and Morphological Properties of Polyolefins

B.G. Millar, P. Douglas, W.R. Murphy, G.M. McNally, May 2005

The effect of cooling rates (2-300degC/min) on the crystallinity, morphology and tensile properties of a selection of polyethylene and polypropylene resins was investigated using conventional and high speed DSC. Increasing cooling rate caused a decrease in percentage crystallinity. Mechanical analysis and polarised light microscopy showed related reductions in tensile modulus and strength and crystallite configuration.

Standardization of High Strain Rate Tensile Testing of Polymers

Susan I. Hill, Margaret F. Pinnell, Adam J. Minch, May 2005

The results of an interlaboratory test program conducted to assess the precision of the Practice Guide for High Strain Rate Testing of Polymers are summarized. Five polymers, HDPE, 30% short glass fiber-filled PA, PC/ABS, 40% long glass fiber-filled PP, and TPO, were tested at nominal plastic strain rates of 40/s and 400/s. The test results were used to generate inter and intralaboratory variability statistics that were incorporated into a precision statement for the Practice Guide.

The Effect of Solar Energy on Decorative Woodgrain Foils Laminated on UPVC Profiles

A.S. Ditta, A.J. Wilkinson, G.M. McNally, W.R. Murphy, May 2005

Decorative woodgrain foils are important in the aesthetic appearance of UPVC profiles in the conservatory industry. Dark colours tend to absorb solar energy which causes distortion when reaching a critical temperature. This research has investigated three different foils subjected to simulated solar energy when placed on UPVC profiles using a specially designed test rig. This equipment failed to give results correlating to outdoor experience, therefore the test will be needed to be modified to be useful.

Chain Extended/Branched PET-Organoclay Nanocomposites

Ulku Yilmazer, Ali Emrah Keyfoglu, May 2005

The effects of chain extension and branching on the properties of nanocomposites produced from recycled poly (ethylene-terephthalate) and organically modified clay were investigated. As the chain extension/branching agent, maleic anhydride (MA) and pyromellitic dianhydride (PMDA) were used. Both MA and PMDA improved the mechanical properties of the nanocomposite owing to the branching and chain extending effects that increase the molecular weight. However, PMDA gave better results at lower content.

The Effect of Thermal History Development on Crystalline Medical Grade TPUs

A.C. Ruddy, G.M. McNally, C.M. Small, May 2005

In this study a range of polyurethanes were extruded in sheet form and cooled at various chill roll temperatures. Crystallinity of the samples was determined using DSC and the results showed significant changes in morphology of the hard and soft segment phases, which in turn had a significant effect on the mechanical properties and phase transitional properties of the individual resins.

Rheological, Mechanical and Thermal Behaviour of Radiopaque Filled Polymers

A.C. Ruddy, G.M. McNally, May 2005

This work studied the effect of three radiopaque fillers (barium sulphate, bismuth trioxide and tungsten metal) on the rheological, mechanical and thermal properties of a range of medical grade polyurethanes and polyvinylchlorides. The results showed significant changes in the melt viscosity, mechanical properties and phase transitions (Tg and log E’) with different filler type.

Chemical Structure Effects on the Performance of TPUs

A.C. Ruddy, G.M. McNally, May 2005

This work studied the effect of polyurethane chemical structure (i.e. polyester or polyether soft segments) on the rheological, mechanical and thermal properties of four commercial medical grade polyurethanes of similar Shore hardness. The results showed significant differences in melt viscosity, tensile properties and phase transition temperatures (tan ?) with particular polyurethane chemical structure.

Foams Extruded from Polystyrene / Thermoplastic Starch Blends

Mihaela Hotea Mihai, Michel A. Huneault, Basil D. Favis, May 2005

This work aims at the development of foams from Polystyrene (PS)/Thermoplastic Starch (TPS) blends. The gelatinization and plasticization of the starch granules, the TPS/PS melt blending and the HFC134a blowing agent dissolution was carried out in a twin-screw extrusion process. The viscosity of the blends, with and without the blowing agent, was measured on-line. The obtained foam morphology, density and open-cell fraction are discussed.

CPVC in Rigid PVC Profile Formulations

W.C. Yap, M. Prichard, G.M. McNally, W.R. Murphy, May 2005

10-50% of CPVC was mixed with UPVC formulations used in extruded profiles for conservatory roofing applications. The shear viscosity, mechanical properties and dynamic mechanical thermal properties of various formulations were shown to be dependent to the CPVC concentration. A blend 40% of CPVC and 60% UPVC exhibited a great increase in mechanical properties.

Impact Stregnth as a Function of Foam Density

Christopher A. Lange, May 2005

Structural high density polyethylene foam is commonly used in many household applications. Is has been accepted by the industry that foaming creates internal space in an injection molded article and therefore allows the part to absorb impacts without initiating cracks. This paper seeks to determine the relationship between the density of a structurally foam molded article and the impact strength.

The Effect of Extrusion Processing Conditions on the Water Vapour Transmission Rates of Polyolefin and Polyamide Packaging Film

M. Billham, B.G. Millar, G.M. McNally, W.R. Murphy, May 2005

The water vapour transmission rate (WVTR) of polymer films is critical in flexible food packaging applications. The WVTR of a series of polyolefin and co-extruded polyethylene/polyamide films were shown to be affected by density, orientation and crystallinity, as well as the cooling process from cast and blown extruded films.

Morphology and Rheology of Polycaprolactone/Thermoplastic Starch Blends

Gang Li, Pierre Sarazin, Zhenhua Yuan, Basil D. Favis, May 2005

Polycaprolactone (PCL)/thermoplastic starch (TPS) biodegradable blends were prepared via a one-step extrusion system over the entire range of composition at different viscosity ratios. A detailed morphology analysis of the PCL/TPS blends was investigated by electron microscopy after selective extraction. Through a judicious combination of concentration control and processing conditions, the volume average diameter of TPS droplets can be closely controlled from 0.5 to 16?m. The rheological behavior of these blends is also examined in depth.

The Effect of Uni-Axial Stretching on the Gas Permeation Properties of LDPE/LLDPE Silage Wrap Films

C. Laffin, G.M. McNally, P.D. Forristal, P. O’Kiely, C.M. Small, May 2005

This work investigates the effect of uni-axial stretching on the gas permeation properties of LLDPE/LDPE films. The results show improved gas barrier properties with increasing uni-axial stretch as a result of increasing film crystallinity and molecular orientation.

A Study on Nalidixic Acid/Polycaprolactone Blends for Medical Device Applications

J. Godinho, I. Moore, L. Donnelly, C.Y. Lew, P. Douglas, D. Jones, G.M. McNally, W.R. Murphy, May 2005

The incorporation of an antibacterial agent within the polymeric matrix can prevent bacterial colonisation on the surface of implanted medical devices. In this study, nalidixic acid was melt blended with polycaprolactone at different concentrations. Its effect on the processability, crystallisation, mechanical properties and drug release were investigated.

Dielectric Properties of Self-Reinforced Polymers

Paul J. Jones, Nick Malkovich, David B. Thomas, Sarah E. Morgan, May 2005

The dielectric constants of two compositions of a new class of rigid rod polymers (Parmax® Self Reinforced Polymers (SRPs)) were measured and demonstrate potential for use in multiple electronic applications. Dielectric measurements were made over a range of frequencies using a Hewlett Packard 4192A LF Impedance Analyzer. At 1MHz the two samples displayed very low dielectric constants of 2.31 and 1.96.

The Optimal Parameters of the Water Assisted Injection Molding Process with ABS Material

Kuo-Zoo Liang, Chin-Chang Yeh, Chein-Chung Chen, May 2005

In this paper, the Water Assisted Injection Molding (WAIM) technology is applied to the design of a new mold. Two kinds of the ABS materials are utilized to undertake tests for the above new designed mold. Good results for the great decrease in the deformation as well as Warpage of the ABS products can be obtained. Finally, the Taguchi Method and Grey Theory are applied to finding the optimal parameters of injection molding process.

Branched Modifiers for High Melt Strength Applications

Lawrence J. Effler, Kim L. Walton, Michael K. Laughner, May 2005

Poly(?-olefin) elastomers (POEs) are used to modify the performance of polypropylene (PP). All the POE modifiers were found to enhance both the room and subambient temperature impact performance. However, POEs containing high levels of long chain branching improved the melt elasticity of the PP. Thus, giving an increase the melt strength of the PP making it more suitable for applications such as thermoforming and blow molding.

Synthesis of Elastomeric Nanoparticles via Microemulsion Polymerization

M. Esther Treviño, Yolanda del Angel, Raúl G. López, Luis F. Ramos, May 2005

Copolymerization of buyl acrylate with dimethyl meta-isopropenyl benzyl isocyanate (TMI) was carried out at 40°C in microemulsions stabilized with a mixture of sodium dodecyl sulfate / sodium bis (2-ethylhexyl) sulfosuccinate (3/1 w/w). The mixture of monomers was dosed during the polymerization. An inverse dependence of particle diameter (DP) on dosing rate of monomers and TMI concentration was found. Polymer content close to 25 wt. % and DP between 30 and 40 nm were obtained.

Structure-Property Relationship and Processing of Nanocomposites

Hemi N. Nae, May 2005

Exfoliated organophilic clays dispersed in a polymeric matrix such as polyolefin, epoxy or polyamide form nanocomposites that exhibit improved mechanical, thermal, flame resistance and barrier properties. The effect of the organoclay’s chemical structure, its polarity and surface chemistry and how it is dispersed in the polymeric matrix determine the properties of the nanocomposite. Various characterization techniques are discussed as well as the effect of processing parameters on the properties of the nanocomposite.