Eileen Harkin-Jones | University of Ulster (original) (raw)

Uploads

Papers by Eileen Harkin-Jones

Research paper thumbnail of Mechanical properties of rotationally molded nyrim

Polymer Engineering and Science, 1996

Rotational molding is used primarily for the manufacture of products from powdered plastics. Howe... more Rotational molding is used primarily for the manufacture of products from powdered plastics. However, there are many advantages to be gained from the use of a liquid plastic feedstock. This paper describes the results of an investigation to study the effect of process variables, such as mold temperature, on the morphology and mechanical properties of parts manufactured by the rotational molding of a reactive liquid nylon, caprolactam plus a diol. Initial mold temperature has a significant effect on the degree of crystallinity, levels drop off sharply at mold temperatures in excess of 140°C, while spherulite size increases after this point. Flexural properties improve with increasing degree of crystallinity while impact strength decreases. A similar trend is observed in moldings containing fillers. A brief study of water uptake and dimensional stability of molded parts is also described.

Research paper thumbnail of The effect of temperature and strain rate on the deformation behaviour, structure development and properties of biaxially stretched PET–clay nanocomposites

Composites Science and Technology, 2011

Research paper thumbnail of Characterisation of melt-processed poly(ethylene terephthalate)/synthetic mica nanocomposite sheet and its biaxial deformation behaviour

Polymer International, 2009

BACKGROUND: Poly(ethylene terephthalate) (PET) is widely used in the packaging industry. In order... more BACKGROUND: Poly(ethylene terephthalate) (PET) is widely used in the packaging industry. In order to enhance the mechanical and barrier properties, nanoscale fillers are added to PET matrices to form nanocomposites. In the work reported here, a melt-processed PET/synthetic mica nanocomposite sheet was characterised to determine the effect of the incorporation of synthetic mica on the sheet properties and also to see if these properties are an indicator of subsequent performance under high-speed, high-temperature biaxial deformation, typical of processes such as stretch blow moulding.RESULTS: The incorporation of synthetic mica was found to enhance the modulus, particularly above the glass transition temperature, and barrier properties of the extruded sheet and it significantly altered the deformation behaviour of PET under biaxial deformation. The plastic flow of PET during biaxial deformation was found to diminish for the nanocomposites, and strain hardening occurred earlier.CONCLUSION: The modulus and barrier properties of PET were enhanced by the incorporation of synthetic mica. Clay loading also altered the biaxial deformation behaviour of PET. Copyright © 2009 Society of Chemical Industry

Research paper thumbnail of Biaxial deformation behavior and mechanical properties of a polypropylene/clay nanocomposite

Composites Science and Technology, 2009

Research paper thumbnail of Evolution of Clay Morphology in Polypropylene/Montmorillonite Nanocomposites upon Equibiaxial Stretching: A Solid-State NMR and TEM Approach

Macromolecules, 2009

Solid-state NMR and TEM were used to quantitatively examine the evolution of clay morphology upon... more Solid-state NMR and TEM were used to quantitatively examine the evolution of clay morphology upon equibiaxial stretching of polypropylene/montmorillonite (PP−MMT) nanocomposites up to a stretch ratio (λ = final length/initial length) of 3.5. 1 H spin−lattice relaxation times ...

Research paper thumbnail of Quantitative characterization of clay dispersion in polypropylene-clay nanocomposites by combined transmission electron microscopy and optical microscopy

Materials Letters, 2010

This paper presents a novel method to describe the microstructure of polymer/clay nanocomposites ... more This paper presents a novel method to describe the microstructure of polymer/clay nanocomposites quantitatively. Based on the image analyses of transmission electron microscopy (TEM) and optical microscopy micrographs, two parameters, degree of dispersion (χ) and mean ...

Research paper thumbnail of Structure–property relationships in biaxially deformed polypropylene nanocomposites

Composites Science and Technology, 2010

Research paper thumbnail of Mechanical properties of rotationally molded nyrim

Polymer Engineering and Science, 1996

Rotational molding is used primarily for the manufacture of products from powdered plastics. Howe... more Rotational molding is used primarily for the manufacture of products from powdered plastics. However, there are many advantages to be gained from the use of a liquid plastic feedstock. This paper describes the results of an investigation to study the effect of process variables, such as mold temperature, on the morphology and mechanical properties of parts manufactured by the rotational molding of a reactive liquid nylon, caprolactam plus a diol. Initial mold temperature has a significant effect on the degree of crystallinity, levels drop off sharply at mold temperatures in excess of 140°C, while spherulite size increases after this point. Flexural properties improve with increasing degree of crystallinity while impact strength decreases. A similar trend is observed in moldings containing fillers. A brief study of water uptake and dimensional stability of molded parts is also described.

Research paper thumbnail of The effect of temperature and strain rate on the deformation behaviour, structure development and properties of biaxially stretched PET–clay nanocomposites

Composites Science and Technology, 2011

Research paper thumbnail of Characterisation of melt-processed poly(ethylene terephthalate)/synthetic mica nanocomposite sheet and its biaxial deformation behaviour

Polymer International, 2009

BACKGROUND: Poly(ethylene terephthalate) (PET) is widely used in the packaging industry. In order... more BACKGROUND: Poly(ethylene terephthalate) (PET) is widely used in the packaging industry. In order to enhance the mechanical and barrier properties, nanoscale fillers are added to PET matrices to form nanocomposites. In the work reported here, a melt-processed PET/synthetic mica nanocomposite sheet was characterised to determine the effect of the incorporation of synthetic mica on the sheet properties and also to see if these properties are an indicator of subsequent performance under high-speed, high-temperature biaxial deformation, typical of processes such as stretch blow moulding.RESULTS: The incorporation of synthetic mica was found to enhance the modulus, particularly above the glass transition temperature, and barrier properties of the extruded sheet and it significantly altered the deformation behaviour of PET under biaxial deformation. The plastic flow of PET during biaxial deformation was found to diminish for the nanocomposites, and strain hardening occurred earlier.CONCLUSION: The modulus and barrier properties of PET were enhanced by the incorporation of synthetic mica. Clay loading also altered the biaxial deformation behaviour of PET. Copyright © 2009 Society of Chemical Industry

Research paper thumbnail of Biaxial deformation behavior and mechanical properties of a polypropylene/clay nanocomposite

Composites Science and Technology, 2009

Research paper thumbnail of Evolution of Clay Morphology in Polypropylene/Montmorillonite Nanocomposites upon Equibiaxial Stretching: A Solid-State NMR and TEM Approach

Macromolecules, 2009

Solid-state NMR and TEM were used to quantitatively examine the evolution of clay morphology upon... more Solid-state NMR and TEM were used to quantitatively examine the evolution of clay morphology upon equibiaxial stretching of polypropylene/montmorillonite (PP−MMT) nanocomposites up to a stretch ratio (λ = final length/initial length) of 3.5. 1 H spin−lattice relaxation times ...

Research paper thumbnail of Quantitative characterization of clay dispersion in polypropylene-clay nanocomposites by combined transmission electron microscopy and optical microscopy

Materials Letters, 2010

This paper presents a novel method to describe the microstructure of polymer/clay nanocomposites ... more This paper presents a novel method to describe the microstructure of polymer/clay nanocomposites quantitatively. Based on the image analyses of transmission electron microscopy (TEM) and optical microscopy micrographs, two parameters, degree of dispersion (χ) and mean ...

Research paper thumbnail of Structure–property relationships in biaxially deformed polypropylene nanocomposites

Composites Science and Technology, 2010

Log In