All Outputs (47)

Modeling non-linear rheology of PLLA: comparison of Giesekus and Rolie-Poly constitutive models (2020)
Journal Article
St?pie?, M., Choong, G. Y., De Focatiis, D. S., & Figiel, ?. (2020). Modeling non-linear rheology of PLLA: comparison of Giesekus and Rolie-Poly constitutive models. International Journal of Biobased Plastics, 2(1), 13-28. https://doi.org/10.1080/24759651.2020.1808367

Rheological models for biobased plastics can assist in predicting optimum processing parameters in industrial forming processes for biobased plastics and their composites such as film blowing, or injection stretch-blow molding in the packaging indust... Read More about Modeling non-linear rheology of PLLA: comparison of Giesekus and Rolie-Poly constitutive models.

A phenomenological constitutive model for the viscoelastic deformation of elastomers (2020)
Journal Article
Annarasa, V., Popov, A. A., & De Focatiis, D. S. A. (2020). A phenomenological constitutive model for the viscoelastic deformation of elastomers. Mechanics of Time-Dependent Materials, https://doi.org/10.1007/s11043-020-09452-2

This study proposes a one-dimensional constitutive model for elastomeric materials based on recent observations regarding the separation of elastic and viscous contributions in uniaxial cyclic tensile experiments on EPDM rubber. The focus is on captu... Read More about A phenomenological constitutive model for the viscoelastic deformation of elastomers.

Adaptation of material deposition parameters to account for out-time effects on prepreg tack (2020)
Journal Article
Smith, A., Endruweit, A., Choong, G., De Focatiis, D., & Hubert, P. (2020). Adaptation of material deposition parameters to account for out-time effects on prepreg tack. Composites Part A: Applied Science and Manufacturing, 133, Article 105835. https://doi.org/10.1016/j.compositesa.2020.105835

A single-stage peel method was employed to determine the relationship between key processing parameters and tack for a standard aerospace carbon/epoxy prepreg subjected to various levels of room-temperature out-time. The temperature-dependent viscoel... Read More about Adaptation of material deposition parameters to account for out-time effects on prepreg tack.

An adaptable flexural test fixture for miniaturised polymer specimens (2020)
Journal Article
Choong, G. Y., Canciani, A., & De Focatiis, D. S. (2020). An adaptable flexural test fixture for miniaturised polymer specimens. Polymer Testing, 85, https://doi.org/10.1016/j.polymertesting.2020.106430

An adaptable flexural test fixture is proposed to characterise the mechanical properties of miniature beam specimens (?10 mg) at ambient conditions or in the presence of fluids at elevated temperatures. The fixture is validated using representative a... Read More about An adaptable flexural test fixture for miniaturised polymer specimens.

Intrinsic dependence of ice adhesion strength on surface roughness (2020)
Journal Article
Memon, H., Liu, J., De Focatiis, D. S., Choi, K., & Hou, X. (2020). Intrinsic dependence of ice adhesion strength on surface roughness. Surface and Coatings Technology, 385, Article 125382. https://doi.org/10.1016/j.surfcoat.2020.125382

The roles of surface roughness on icephobicity including ice adhesion strength have been long debated in icephobicity studies. However, the direct/systematic influence of surface roughness on ice adhesion strength while keeping other surface characte... Read More about Intrinsic dependence of ice adhesion strength on surface roughness.

A novel criterion for the prediction of meso-scale defects in textile preforming (2019)
Journal Article
Matveev, M. Y., Endruweit, A., De Focatiis, D. S., Long, A. C., & Warrior, N. A. (2019). A novel criterion for the prediction of meso-scale defects in textile preforming. Composite Structures, 226, Article 111263. https://doi.org/10.1016/j.compstruct.2019.111263

© 2019 The Authors In numerical simulations of reinforcement preforming, fabrics are often modelled using continuum approaches with homogenised material properties in order to reduce the computational costs. To predict the occurrence of meso-scale de... Read More about A novel criterion for the prediction of meso-scale defects in textile preforming.

In-situ icing and water condensation study on different topographical surfaces (2019)
Journal Article
Memon, H., Liu, J., Weston, N., Wang, J., De Focatiis, D., Choi, K., & Hou, X. (2019). In-situ icing and water condensation study on different topographical surfaces. Cold Regions Science and Technology, 165, Article 102814. https://doi.org/10.1016/j.coldregions.2019.102814

Icephobicity is intrinsically affected by rough asperities and the surface voids provide anchoring points for the ice. The anchor of ice is likely to form on the surface under high humidity conditions. In-situ water condensation and icing observation... Read More about In-situ icing and water condensation study on different topographical surfaces.

Challenges to the industrial melt-processing of conductive plastics (2019)
Journal Article
Choong, G. Y. H., De Focatiis, D. S. A., Lidgett, M. J., Thornton, M. J., & Clifford, M. J. (2019). Challenges to the industrial melt-processing of conductive plastics. AIP Conference Proceedings, 2055, 090003-1 to 090003-5. https://doi.org/10.1063/1.5084881

In this work, we investigate the relationship between the timescales available for polymer mobility during processing and post-processing and the electrical resistivity of melt-processed thermoplastics filled with carbon nanoparticles. Post-process a... Read More about Challenges to the industrial melt-processing of conductive plastics.

The development of a novel technique for small ring specimen tensile testing (2018)
Journal Article
Kazakeviciute, J., Rouse, J., De Focatiis, D., & Hyde, C. (2019). The development of a novel technique for small ring specimen tensile testing. Theoretical and Applied Fracture Mechanics, 99, 131-139. https://doi.org/10.1016/j.tafmec.2018.11.016

The wide scale use of small specimens in routine testing programs could significantly reduce material resource requirements (factors of 10 are easily achievable). This is a major benefit to situations where there is not enough material to manufacture... Read More about The development of a novel technique for small ring specimen tensile testing.

Characterisation of tack for uni-directional prepreg tape employing a continuous application-and-peel test method (2018)
Journal Article
Endruweit, A., Choong, G. Y., Ghose, S., Johnson, B. A., Younkin, D. R., Warrior, N. A., & De Focatiis, D. S. (2018). Characterisation of tack for uni-directional prepreg tape employing a continuous application-and-peel test method. Composites Part A: Applied Science and Manufacturing, 114, 295-306. https://doi.org/10.1016/j.compositesa.2018.08.027

Employing a test method with coupled application and peel phases, tack was characterised for a UD prepreg tape. Different aspects of tack were explored by varying test parameters and material condition. In addition, different surface combinations wer... Read More about Characterisation of tack for uni-directional prepreg tape employing a continuous application-and-peel test method.

Frictional behaviour of non-crimp fabrics (NCFs) in contact with a forming tool (2018)
Journal Article
Avgoulas, E. I., Mulvihill, D. M., Endruweit, A., Sutcliffe, M. P., Warrior, N. A., De Focatiis, D. S., & Long, A. C. (2018). Frictional behaviour of non-crimp fabrics (NCFs) in contact with a forming tool. Tribology International, 121, 71-77. https://doi.org/10.1016/j.triboint.2018.01.026

Microscopic observation and analysis are used to examine the role that contact conditions play in determining the frictional behaviour of non-crimp fabrics (NCFs). The true fibre contact length is measured over a range of normal pressures. For the NC... Read More about Frictional behaviour of non-crimp fabrics (NCFs) in contact with a forming tool.

The Roles of Blending and of Molecular Weight Distribution on Craze Initiation (2017)
Journal Article
Sánchez-Valencia, A., Smerdova, O., Hutchings, L. R., & De Focatiis, D. S. A. (2017). The Roles of Blending and of Molecular Weight Distribution on Craze Initiation. Macromolecules, 50(23), 9507-9514. https://doi.org/10.1021/acs.macromol.7b01289

Craze initiation stress was measured in three-point bending isochronal creep tests on a series of entangled bimodal blends of polystyrenes of narrow dispersity, on three polystyrenes of broad dispersity, and on four blends of polystyrenes of broad di... Read More about The Roles of Blending and of Molecular Weight Distribution on Craze Initiation.

Can a combination of poly(ethylene glycol) and dense phase carbon dioxide improve processing of polylactide? A high pressure rheology investigation (2017)
Journal Article
Pepper, K., Masson, T., De Focatiis, D. S., & Howdle, S. M. (in press). Can a combination of poly(ethylene glycol) and dense phase carbon dioxide improve processing of polylactide? A high pressure rheology investigation. Journal of Supercritical Fluids, 133(1), https://doi.org/10.1016/j.supflu.2017.10.014

High temperature melts or use of organic solvents are not practicable approaches for encapsulating protein based or thermally labile drugs into degradable polymers. Here, we demonstrate that poly(ethylene glycol) (PEG) in combination with supercritic... Read More about Can a combination of poly(ethylene glycol) and dense phase carbon dioxide improve processing of polylactide? A high pressure rheology investigation.

Double diaphragm forming simulation for complex composite structures (2017)
Journal Article
Chen, S., McGregor, O., Endruweit, A., Elsmore, M., De Focatiis, D., Harper, L., & Warrior, N. (2017). Double diaphragm forming simulation for complex composite structures. Composites Part A: Applied Science and Manufacturing, 95, 346-358. https://doi.org/10.1016/j.compositesa.2017.01.017

A finite element (FE) model has been developed to simulate the double diaphragm forming (DDF) process, to identify potential defects when forming complex 3D preforms from 2D biaxial non-crimp fabric plies. Three different metrics have been introduced... Read More about Double diaphragm forming simulation for complex composite structures.

Compression moulding of composites with hybrid fibre architectures (2016)
Journal Article
Corbridge, D., Harper, L. T., De Focatiis, D. S., & Warrior, N. (2017). Compression moulding of composites with hybrid fibre architectures. Composites Part A: Applied Science and Manufacturing, 95, 87-99. https://doi.org/10.1016/j.compositesa.2016.12.018

Advanced Sheet Moulding Compounds (ASMC) and unidirectional (UD) prepregs have been co-compression moulded to form a hybrid composite material. In-mould flow influences the UD fibre architecture in two ways. When UD fibres are aligned transversely to... Read More about Compression moulding of composites with hybrid fibre architectures.

A method for the determination and correction of the effect of thermal degradation on the viscoelastic properties of degradable polymers (2016)
Journal Article
Choong, G. Y. H., & De Focatiis, D. S. (2016). A method for the determination and correction of the effect of thermal degradation on the viscoelastic properties of degradable polymers. Polymer Degradation and Stability, 130, 182-188. https://doi.org/10.1016/j.polymdegradstab.2016.06.018

Small amplitude oscillatory shear is carried out during isothermal degradation of poly(lactic acid) (PLA) in order to determine the evolution of the characteristic relaxation time with degradation time and temperature. After reducing the relaxation t... Read More about A method for the determination and correction of the effect of thermal degradation on the viscoelastic properties of degradable polymers.

A model for the compressible, viscoelastic behavior of human amnion addressing tissue variability through a single parameter (2015)
Journal Article
Mauri, A., Ehret, A. E., De Focatiis, D. S., & Mazza, E. (2016). A model for the compressible, viscoelastic behavior of human amnion addressing tissue variability through a single parameter. Biomechanics and Modeling in Mechanobiology, 15(4), 1005-1017. https://doi.org/10.1007/s10237-015-0739-0

A viscoelastic, compressible model is proposed to rationalize the recently reported response of human amnion in multiaxial relaxation and creep experiments. The theory includes two viscoelastic contributions responsible for the sho... Read More about A model for the compressible, viscoelastic behavior of human amnion addressing tissue variability through a single parameter.

Rheological techniques for determining degradation of polylactic acid in bioresorbable medical polymer systems (2015)
Journal Article
Choong, G. Y., Parsons, A. J., Grant, D. M., & De Focatiis, D. S. (2015). Rheological techniques for determining degradation of polylactic acid in bioresorbable medical polymer systems. AIP Conference Proceedings, 1664, Article 170005. https://doi.org/10.1063/1.4918523

© 2015 AIP Publishing LLC. A method developed in the 1980s for the conversion of linear rheological data to molar mab distribution is revisited in the context of degradable polymers. The method is first applied using linear rheology for a linear poly... Read More about Rheological techniques for determining degradation of polylactic acid in bioresorbable medical polymer systems.

High-pressure rheological analysis of CO2-induced melting point depression and viscosity reduction of poly(?-caprolactone) (2015)
Journal Article
Curia, S., De Focatiis, D. S., & Howdle, S. M. (2015). High-pressure rheological analysis of CO2-induced melting point depression and viscosity reduction of poly(?-caprolactone). Polymer, 69, https://doi.org/10.1016/j.polymer.2015.05.026

High-pressure rheology has been used to assess the effects of supercritical carbon dioxide (scCO2) on the melting point (Tm) and viscosity of poly (?-caprolactone) (PCL) over a range of temperatures and pressures up to 300 bar over a wide range of sh... Read More about High-pressure rheological analysis of CO2-induced melting point depression and viscosity reduction of poly(?-caprolactone).

Role of processing history on the mechanical and electrical behavior of melt-compounded polycarbonate-multiwalled carbon nanotube nanocomposites (2015)
Journal Article
Choong, G. Y. H., Lew, C. Y., & De Focatiis, D. S. (in press). Role of processing history on the mechanical and electrical behavior of melt-compounded polycarbonate-multiwalled carbon nanotube nanocomposites. Journal of Applied Polymer Science, 132(8), Article 42277. https://doi.org/10.1002/app.42277

This work investigates the effects of primary compounding temperature and secondary melt processes on the mechanical response and electrical resistivity of polycarbonate filled with 3 wt % multiwalled carbon nanotubes (CNT). Nanocomposites were melt... Read More about Role of processing history on the mechanical and electrical behavior of melt-compounded polycarbonate-multiwalled carbon nanotube nanocomposites.