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!
| = Members Only |
|
Categories
|
Conference Proceedings
SELF-NUCLEATED CRYSTALLIZATION OF A BRANCHED POLYPROPYLENE
Long chain branched polypropylene (LCBPP) crystallizes rapidly and with high nucleation density. The origin of this fast crystallization process of is not well understood. It has been attributed to its complicated molecular architecture. In this research, we explore isothermal crystallization of LCBPP through rheological, thermal, and optical measurements. The time resolved mechanical spectroscopy technique was used to predict the liquid-to-solid transition (gel point) of LCBPP.
SYNTHESIS AND PROPERTIES OF MULTIFUNCTIONAL EPOXY RESIN BASED COATINGS
The influence of polymeric modifiers such as polyurea and polymethylhydrosiloxane on the properties of epoxy ester coatings was investigated. The corrosion resistance of the hybrid coatings was measured by direct current polarization method, DCP.The dynamic mechanical property of the coatings was determined by using dynamic mechanical spectroscopy. The electrochemical and thermo-mechanical performance of hybrid coatings was compared with those for the neat epoxy ester coating.
PREDICTION OF DEGRADATION OF POLYMER TUBES USED IN SOLAR DOMESTIC HOT WATER COMPONENTS
For polyolefin tubes exposed to chlorinated hot water, lifetime is estimated by a model of the depletion of antioxidant through diffusion and reaction with chlorine ions. A case study for typical tube geometries used in solar hot water applications at 50C is presented. Characteristic time scales demonstrate that the dominant mechanism for antioxidant depletion is the reaction with chlorine ions that diffuse into the polymer tube.
ACOUSTIC STRESS MEASUREMENT IN BIAXIALLY CONSTRAINED MEMBRANES
The growth of center cracks in biaxially confined membranes is monitored as a function of solvent evaporation. In a complimentary study, acoustic and membrane inflation techniques, applied to uncracked membranes, are used to calculate the stresses that cause crack propagation. By comparing the stresses induced in uncracked membranes with crack growth in cracked membranes we are able to calculate values of the stress intensity factor in biaxially constrained membranes with application to industrial coatings.
POLYMER NANOCOMPOSITES WITH COPPER NANOWIRE AND CARBON NANOTUBES: HYBRID MATERIALS EXHIBITING LOW ELECTRICAL PERCOLATION THRESHOLDS, HIGH ELECTRICAL CONDUCTIVITY, AND HIGH EMI SHIELDING
Hybrid nanocomposites of multi-walled carbon nanotubes and copper nanowires in polystyrene were prepared by miscible mixing and precipitation method. Extremely low electrical percolation thresholds in MWNT/PS and CuNW/PS nanocomposites were observed at 0.052 and 0.67 vol. percent, respectively. Electrically conductive polymer nanocomposites exhibiting high Electromagnetic Interference (EMI) Shielding effectiveness are reported.
EVALUATION OF MECHANICAL PROPERTIES OF USED MATERIALS FOR PLASTIC RECYCLE
This paper describes the evaluation of mechanical test results of compounded used polyethylene (PE) pipes and plastic materials for recycle. A compounding technology of used PE pipes for gas distribution and waste polyethylene terephthalate (PET) bottles using a compatibilizer was firstly studied. Then the other combinations of used plastic materials and new resins were also investigated for material uses and high-performance polymer alloys.
RESPONSIVE HYDROGELS PRODUCED VIA ORGANIC SOL-GEL CHEMISTRY FOR BIOMEDICAL APPLICATIONS
We report the synthesis of novel polyurea networks produced via organic sol-gel chemistry, through the combination of an aliphatic triisocyanate with amine-functional polyether and poly(ethyleneimine) segments. Network formation is rapid and requires no catalyst. The resultant materials exhibit pH responsive swelling and show compatibility with human cells. As such, these materials have potential utility in cell culture as a means of stabilizing pH and delivering nutrients.
NANOCOMPOSITE MULTILAYER FILMS OF ETHYLENE CO-VINYL ALCOHOL WITH KAOLINFOR HIGH BARRIER FOOD PACKAGING
Nanocomposite films were investigated to improve oxygen barrier properties for food packaging applications. Ethylene co-vinyl alcohol (EVOH) was used to let-down an EVOH nanocomposite masterbatch to 1, 3 and 5% loadings utilizing kaolin as the nanoparticle. Co-extrusion was used to produce 5-layer blown films consisting of the EVOH/kaolin nanocomposite core layer. Films were characterized before and after retort sterilization for thermal, mechanical, and barrier properties to determine any dependence upon nanoparticle concentration.
BIODEGRADATION OF POLY (HYDROXY BUTANOIC ACID) COPOLYMERS
Biodegradable plastics have attracted much attention in the last decade, not only because they can divert waste from landfill, but also because the biodegradable functionality meets the requirement of many applications. Poly (hydroxy butanoic acid) or PHB copolymers is one such class of plastics. This paper will review the biodegradability of these polymers in various environments including soil, fresh water, seawater, compost and anaerobic digesters. Testing methods and variables influencing biodegradation will also be discussed.
BIODEGRADATION OF POLY (HYDROXY BUTANOIC ACID) COPOLYMERS
Biodegradable plastics have attracted much attention in the last decade, not only because they can divert waste from landfill, but also because the biodegradable functionality meets the requirement of many applications. Poly (hydroxy butanoic acid) or PHB copolymers is one such class of plastics. This paper will review the biodegradability of these polymers in various environments including soil, fresh water, seawater, compost and anaerobic digesters. Testing methods and variables influencing biodegradation will also be discussed.
EFFECT OF BACKWARD MELT FLOW ON INJECTION-COMPRESSION MOLDED PART THICKNESS DISTRIBUTION
In this work, the effects of processing factors during injection-compression molding (ICM) on the thickness distribution of the polystyrene (PS) part are experimentally investigated. Moreover, the generalized Hele-Shaw flow simulation is carried out to predict the melt flow within the cavity during ICM, which gives insight into the backward melt flow and assists in interpreting the experimental observations of the part thickness distribution.
EVALUATION OF LONG-TERM PERFORMANCE OF GLASS-FIBER REINFORCED PLASTICS FOR HOT WATER APPLICATIONBY INJECTION MOLDING
The long glass-fiber reinforced polyphenylene sulfide and short glass-fiber and long glass-fiber reinforced syndiotactic polystyrene by injection molding were tested to evaluate the long-term performance at the elevated temperature in water and in air. As a result, the tensile strength of PPS and SPS after 7000 hours at 150 degrees C in hot water decreased due to degradation at the interface between a matrix resin and a glass fiber.
THE EXPERIMENTAL STUDY ON PURGING OF INJECTION MOLDING MACHINE
This research was to study on purging of injection molding machine. The polypropylene was used in this study. The fractional design was used to design the experiments with five main factors and two levels such as processing temperature, injection pressure, screw speed, injection velocity, and suck-back position. Some interactions were shown with the analysis by Minitab. Those factors were effect in purging. The recommend to purge the PP were using high level of screw speed, injection velocity and suck back position while the processing temperature and injection pressure should be in the low level.
STUDY ON THE S/B MULTIBLOCK COPOLYMER SYNTHESIZED BY REACTIVE EXTRUSION----STRUCTURE CHARACTERIZATION OF THE S/B COPOLYMER AND BUBBLE THEORY
In this work, styrene/butadiene (S/B) copolymer was synthesized via anionic bulk polymerization using a twin-screw extruder as a reactor and butyl lithium as the initiator. The structure of the copolymer was characterized by FT-IR, 1H-NMR, TEM and DMA. It was found that macromolecule structure of prepared copolymer was composed of a long PS block, several short PS and PB blocks. A bubble theory was proposed to explain this result.
EFFECT OF WALL SLIP ON THE FLOW IN A FLAT DIE FOR SHEET EXTRUSION
Flow in a flat die with coat hanger type of manifold is simulated allowing slip on die walls. Flow in the same die was also simulated by enforcing the no-slip condition on the walls. With slip on the die walls, the pressure drop, shear rate, stress, as well as temperature increase in the die, all were smaller than the corresponding values with no-slip condition on the walls. Due to its high computational efficiency, the software employed in this work can be effectively used to design extrusion dies for fluids exhibiting slip on die walls.
GREEN MANDATES OPENING UP A NEW SALES CHANNEL AND GROWTH POTENTIAL FOR MATERIALS COMPANIES
Audience members will learn the following: › Overview of the six green mandates and the opportunities they create for materials companies › Discuss which technologies are currently winning government contracts and why › Identify where the money is being spent currently and trends for future spending › Review best practices in how materials companies can access to those funds to grow their business
DETERMINING OPTIMUM VENT SIZES FOR INJECTION MOLDS
A mold was designed and built to study the optimum size of the vents in injection molds. Results demonstrated that vent sizes were dictated by the part design in the vent area. The higher the local shear rate, the lower is the viscosity of the polymer, limiting the vent depths. The injection phase of the molding cycle is the high shear phase and the pack and hold phases are the low shear phases. Vent depths can therefore vary depending on their location. A method to estimate the dimensions of a vent in a future work is proposed.
STRUCTURE-PROPERTIES RELATIONSHIP IN SEGMENTED POLYURETHANE/SILICA NANOPARTICLE COMPOSITES
Segmented polyurethanes (SPUs) have been synthesized possessing 25, 35 and 45 wt% hard segment. We have added 12 nm silica nanoparticles (SiNPs) during SPU synthesis and after with less than 5wt% loading. Drastic effects on morphology and properties were observed. Covalently attached SiNPs enhanced elongation to break and tensile strength until a critical concentration while blended composites exhibited decreased mechanical robustness. Composite structure and properties were examined.
USING MATHEMATICAL MODELING TO PREDICT SHELF-LIFE
The use of performance modeling is becoming more and more critical in the packaging industry as lightweighting efforts continue to be at the forefront. The primary driver for reducing the amount of material used in packaging is cost reduction. It is critical to not compromise the shelf life of the product. This paper will explain the theory of permeation as it is applied to food and beverage applications and document how the mathematics have been incorporated into an industry standard software application titled M-Rule Container Performance Models.
RAPID RESTORATION OF RAIL ROAD TIMBER BRIDGESUSING POLYMER COMPOSITES
Damaged piles of eleven timber railroad bridges on South Branch Valley Railroad (SBVR) lines in Moorefield, WV were rapidly rehabilitated and restored with the use of Glass Fiber Reinforced Polymer (GFRP) composites. Specifically, field rehabilitation involved repairing of 57 piles using GFRP composite wraps, phenolic formaldehyde resins, and resin soaked wood sawdust as a filler material in the pile core. Following the restoration of timber piles, Non-Destructive Evaluations (NDE) were carried out to assess wrap bonding and core integrity.
|
This item is only available to members
Click here to log in
If you are not currently a member,
you can click here to fill out a member
application.
We're sorry, but your current web site security status does not grant you access to the resource you are attempting to view.
.jpg)
.jpg)
.jpg)
.jpg)
