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

DIRECT ISOLATION OF POLYPHENYLENE ETHER-POLYSILOXANE BLOCK COPOLYMER

Alvaro Carrillo, Gerardo Rocha, May 2011

A polyphenylene ether-polysiloxane block copolymer is produced by oxidative coupling polymerization of 2,6 xylenol and a eugenol-terminated polydimethylsiloxane. The reaction takes place in a solvent, such as toluene, which needs to be removed in an polymer isolation step. The isolation can be done by precipitation of the polymer with an anti-solvent such as methanol, or by direct" isolation in a devolatilizing extruder as described in this paper. Process conditions to control the desired residual solvent content in the product are reported as well as the effect of the process on key product properties."

GAS PERMEABILITY OF ORIENTED POLY(ETHER-B-AMIDE) (PEBAX) COPOLYMERS

Shannon Armstrong, Donald Paul, Benny Freeman, Anne Hiltner, Eric Baer, May 2011

Poly(ether-b-amide) (PEBAX) thermoplastic elastomers are used in high flux applications such as gas separation membranes. PEBAX grades with high polyether soft block content are favorable for gas separation applications due to a high permeability. Permeability measurements on uniaxially oriented PEBAX films in the stretched and recovered state showed a significant decrease between the unoriented films and 400% strained films. WAXS and DSC were used to identify strain-induced crystallization of the polyether blocks, resulting in a 3.5x permeability decrease for oriented PEBAX films.

FACILE THERMOPLASTIC OLEFIN (TPO) DISPERSION USING EXTENSIONAL MIXING

Stephane Costeux, Mark Barger, Keith Luker, Anand Badami, Kim Walton, May 2011

The mixing performance of a small-scale extensional mixer (Spiral Fluted Extensional Mixer, or SFEM) was benchmarked against a mixing bowl. TPO blends were chosen for this evaluation, with a broad range of elastomer melt indices. Various statistical metrics were evaluated to quantify the degree of dispersion of the blends. The conclusion is that due to stronger extensional flow, the SFEM batch mixer indeed has potential to offer better TPO dispersion than mixers with rotors in which shear dominates. A single-screw extruder equipped with SFEM mixing elements achieved even finer dispersion, usually achievable only with twin screw extruders.

EXPERIMENTAL INVESTIGATIONS ON THE IMPACT BEHAVIOR OF HYBRID STEEL-FRP STRUCTURES IN 3-POINT-BENDING TESTS

Christian Mildner, Norbert Dolle, Klaus Drechsler, Robert Bjekovic, May 2011

This paper presents an experimental investigation of the mechanical behavior of hybrid metal hat sections, reinforced with fiber reinforced plastics in 3-point-bending tests. The combination of FRP laminates with metal structures leads to an advanced hybrid material system evaluated for future automobile primary structures. A systematic high velocity impact testing program under 3-point-bending was conducted. To evaluate the impact performance and damage resistance, the load-displacement curves referred to the single steel hat section were used. Variations of fiber types (carbon, glass, aramid) and combinations of such fibers are discussed. Furthermore, the influence of laminate thicknesses and fiber orientations is considered.

UNDERSTANDING THE CHALLENGES OF BONDING TPE MEDICAL TUBING TO TRADITIONAL CONNECTORS

Kevin Cai, Darnell Worley, Elliott Pritikin, May 2011

The non or low polarity of TPEs is typically referenced as the main contributor to their poor bondability. This paper highlights additional technical factors in poor bondability with traditional solvents and commercial adhesives. Medical tubing OEMs focus on TPEs from 65A to 85A hardness depending on the specific application requirements. TPE hardness and modulus are shown to have significant influence on bonding strength. Often overlooked, ƒ??Poisson Effectƒ is shown to be an important factor to cause low retention values with soft flexible TPEs. To overcome these challenges, we developed 3 patent pending bonding systems that significantly improve the bonding strength.

SOLID AND MICROCELLULAR RECYCLED POLY(ETHYLENE TEREPHTHALATE) (PET) BLENDS WITH CHAIN EXTENDERS (CE) AND NANOCLAY

Yottha Srithep, Lih-Sheng Turng, May 2011

Recycled poly(ethylene terephthalate) (RPET) chain extender (CE) and nanoclay were prepared via conventional and microcellular injection molding processes. The effects of CE loading levels and the simultaneous addition of nanoclay on the thermal and mechanical properties and cell morphology of the microcellular components were noted. The addition of 1.3 wt% CE enhanced the tensile properties and viscosity of RPET. The higher amount of CE (at 3 wt%) enhanced the viscosity, but margin of improvement in mechanical properties diminished. While the solid RPET and CE blends were fairly ductile, the samples with nanoclay and all microcellular specimens showed brittle fractural behavior.

INFRARED-REFLECTIVE ENGINEERING THERMOPLASTICS

Christopher Hein, Olga Kuvshinnikova, May 2011

The infrared portion of the electromagnetic spectrum may be used for a variety of purposes in engineering thermoplastics. This paper will explain strategies to develop materials having tailored infrared properties. Inorganic colorants were combined to meet military specifications for near-infrared (NIR) reflective camouflage colors. Opaque colors can be formulated to match under visible illumination and offer analytical detection in the infrared for convenient authentication. Heat storage can be controlled in ASA alloys in dark colors with excellent weatherability.

IMPACT OF FIBER ORIENTATION ON PHYSICAL PROPERTIES OF GLASS-FILLED POLYBUTYLENE TEREPHTHALATE

Himanshu Asthana, Angelika Clark, Subrata Nayak, Krishnamoorthy Narasimhan, May 2011

A combination of experimental observations and simulation methods has been used to determine the effect of side- and end-gate locations, respectively, on tensile stress at break for glass-filled polybutylene terephthalate (PBT) polymer. A hypothesis based on the stress distribution in the molded bars of two respective geometries has been presented. Simulation techniques using C-mold software has been used to confirm the hypothesis. The two sets of data together show that stress non-uniformity in the bars can play a role in determining the location and path of failure.

VARIABILITY IN STANDARD TWO-PROBE AND FOUR-PROBE ELECTRICAL RESISTIVITY MEASUREMENTS OF CARBON NANOTUBE COMPOSITES

Jane Spikowski, Cameron Gibbins, Craig Shoemaker, Jill Kinzelman, May 2011

This study characterizes sources of variability in electrical resistivity measurements of polycarbonate (PC) and carbon nanotube (CNT) composites. A two-probe measurement configuration in compliance with ASTM D 257 and ESD STM 11.11/11.12 was modified by incrementally applying additional force to the probe. This modification was found to significantly reduce variability attributable to contact resistance. A four-point probe measurement configuration in compliance with ASTM F 43-93 and ASTM F 84-98 was used to characterize local variations in resistivity within injection molded disks.

DESIGN AND INJECTION MOLDING FACTORS THAT AFFECT OVERMOLDING BOND STRENGTH

David Raia, May 2011

The product development team should always be asking the question: How strong does the bond strength need to be for a product design. Some products get used once and do not require high performance bond strength, while others are handled often and require higher bond stength. This paper focuses on both the design and molding factors that affect the ultimate bond strength between a polar plastic substrate and an overmolding TPE compound. It reviews not only ultimate bond strength, but factors that influence bond strength consistency. This information is important to both the product designer and the injection molder.

POLYMER DEGRADATION DURING CONTOUR LASER TRANSMISSION WELDING

Phil Bates, Sina Khosravi, Gene Zak, May 2011

This paper presents an experimental technique for assessing material degradation during contour laser transmission welding. Polymer is characterized using thermal gravimetric analysis (TGA). The experimental TGA degradation data are fitted to a kinetic model using the Freeman-Carroll technique. This model allows the fraction of degraded material to be predicted as a function of temperature and time. A FEM model is then used to predict temperature as a function of time at the weld for different laser and material parameters. The two models are combined to estimate material degradation at the weld interface. These results are related to experimental observations.

SYNTHESIS AND THERMAL STABILITY STUDIES OF NOVEL THERMALLY STABLE EPOXY-POLYURETHANE COMPOSITES

Jing Lin, Qiuzhuan, Zhi-qi Cai, Xiufang Wen, Pihui Pi, Jiang Cheng, Zhuoru Yang, May 2011

A series of hydroxyl terminated bisphenol-A type novolac epoxy resins modified with benzoic acid (MEP) were prepared. The chemical structures of MEP were characterized using FTIR analyses. And epoxy-polyurethane composites were also obtained by curing reaction among MEP, cross linker polyisocyanate IL1351 and phthalic anhydride. The thermal stability of cured products was studied by thermogravimetric analysis (TGA). The thermal stability of the cured MEP with different ring-opening rate, cured bisphenol-A type novolac epoxy resins and cured alkyd polyol A450 were compared.

DYNAMIC MECHANICAL ANALYSIS OF FDM RAPID PROTOTYPING PROCESSED POLYCARBONATE MATERIAL

Adhiyamaan Arivazhagen, Syed Masood, Igor Sbarski, May 2011

This paper aims to investigate the dynamic mechanical properties of Polycarbonate material processed by Fused Deposition Modeling (FDM) rapid prototyping process. Frequency sweep is performed in Dynamic Mechanical Analysis (DMA) 2980 equipment to get modulus, damping and viscosity values. The effects of FDM parameters (built style, raster width, and raster angle) over these properties are presented. Frequency sweep experiment is done with the range of 10 Hz to 100 Hz in three different isothermal temperatures. It is found that solid normal built style gives more modulus and viscosity values than the other built styles.

EXFOLIATION AIDS FOR PREPARATION OF POLYMER-LAYERED SILICATE NANOCOMPOSITES

Jinling Liu, William Rodgers, Ting Cao, Michael Thompson, May 2011

The use of supercritical CO2 and two cosolvents were examined to aid exfoliation of an organoclay within a thermoplastic polyolefin. The study examined the manner in which the gas environment was used in the presence of the clay, compatibilizer and matrix. This was done with an extensional flow mixer. The results of the work showed that supercritical CO2 was most effectively utilized when in the presence of the organoclay and compatibilizer as it melted. Both water and ethanol were effective cosolvents, producing smaller tactoids with a narrower size distribution. Ethanol was found to be the most effective as a cosolvent.

HOT MELT MIXING OF INDOMETHACIN AND SOLUPLUS FOR ORAL DELIVERY

Graciela Terife, Costas Gogo, Peng Wang, May 2011

An amorphous solid suspension for oral drug delivery was prepared via Hot Melt mixing 30wt% of Indomethacin (INM) with Soluplus. The melt mixed sample was characterized through optical microscopy, DSC, FR-IR and XRD. Dissolution test showed that INM release was pH-dependent; in the case of the amorphous solid suspension within 1h 90% of INM was released at pH7.4, while only 0.02% at pH1.2, probably a consequence of hydrogen bonds formed between INM and the polymer. The fastest release was obtained from the foamed amorphous solid suspension, followed by un-foamed amorphous solid suspension, then pure INM and finally the physical mixture.

EFFECT OF THE ADDITION OF CARBON NANOTUBES WITH POLYSTYRENE GRAFTING ON THE GLASS TRANSITION BEHAVIOR OF POLYSTYRENE

Brian Grady, Abhijit Paul, Warren Ford, May 2011

The effect of single-walled carbon nanotubes on the glass transition of polystyrene with and without polystyrene grafting has been quantified. Three different molecular weights, 2,800, 15,000 and 50,000 g/mol, of polystyrene were grafted to the nanotubes with the weight fractions of grafted chains approximately the same. Composites with 50 K grafted nanotubes were statistically identical in terms of the glass transition temperature and change in heat capacity. Composites with lower molecular weight grafted nanotubes did show significant differences vs. the composites with ungrafted nanotubes, especially in terms of the change in heat capacity.

EFFECT OF MOLECULAR WEIGHT DISTRIBUTION ON THE WELD-LINE INTERFACE IN INJECTION MOLDED POLYPROPYLENE

Katsuyuki Yokomizo, May 2011

On the basis of a coarse-grained molecular dynamics with bead-spring polymer chain model, we investigated an interdiffusion of macromolecules of the separated flow fronts and stress-strain behavior under simple extensional deformation of the interfacial region. In polydisperse system, it is predicted that depletion of long chains takes place at the interface where short chains preferentially locate. Significant improvement of interfacial strength is predicted when molecular weight distribution is narrow enough to have a considerable overlap between long chains belonging to each phase separated by the interface. The calculation result reproduced the experiment on the interfacial strength of polyolefin material.

PROPERTIES OF POLY (PROPYLENE CARBONATE) PRODUCED VIA SK ENERGY'S GREENPOL TECHNOLOGY

Myung-Ahn Ok, Minho Jeon, May 2011

Polypropylene carbonate (PPC) is an amorphous polymer made by alternating copolymerization of carbon dioxide and propylene oxide. SK Energy developed its own proprietary technology with a highly active catalyst for this polymerization and has begun to produce PPC in its continuous process type pilot plant since late 2008 with a trade name GreenPolTM. In this paper, we are describing the typical properties of PPC such as general physical properties, barrier properties, thermal and UV stability, and smoke density along with some rheological properties.

A GREEN PROCESS FOR THE SYNTHESIS OF MESOPOROUS SILICA MATERIALS

Honghu Dai, Daoxing Dai, Jintao Yang, Yunguo Zhou, Zhengdong Fei, Feng Chen, Mingqiang Zhong, May 2011

In this paper, mesoporous silica and functionalized silicas were prepared by a green template, polyamidoamine (PAMAM) dendrimers. Three silane coupling agents, 3-triethoxysilylpropyl- amine (APTES), -methylacryloyl oxypropyl trimethoxysilane (MAPTMS) and N-[3-(trimethoxysilyl)propyl]ethylenediamine (AEAPTMS) were used for modification on pore surface. The characters of synthesized silicas were investigated in detail. The results showed that controllable pore diameters, narrow pore size distributions, high surface area and pore volume were achieved. The PAMAM template can be feasibly removed by using water extraction.

THE APPLICATION OF DENDRIMER IN ULTRAHIGH MOLECULAR WEIGHT POLYETHYLENE PROCESSING

Daoxing Dai, Honghu Dai, Jintao Yang, Zhengdong Fei, Feng Chen, Mingqiang Zhong, May 2011

In this paper, poly(amido amine) (PAMAM) dendrimer, its lauryl quaternary ammonium salt and steary quaternary ammonium salt were used for blending modification of ultrahigh molecular weight polyethylene. The effects of modifiers on viscosity reduction, crystalline properties were investigated by torque rheometer, differential scanning calorimetry, X-ray diffraction analysis, etc. The results showed that three modifiers could decrease the melt viscosity of UHMWPE, which could be further explained from the view of distanglement.