Applied Rheology: Publications

Contributions
matching >Anton.S<

Follow the blue link(s) below for abstracts and full text pdfs .

  Author index
  Most cited recent articles
  Articles for free download
  Search conferences
Mercedes Fernandez, Arrate Huegun, Maria Eugenia Munoz, Anton.Santamaria
Nonlinear oscillatory shear flow as a tool to characterize irradiated polypropylene/MWCNT nanocomposites

Appl. Rheol. 25:4 (2015) 45154 (12 pages)

The relative intensity and phase of the third harmonic, I3/1 and Φ31, deduced from Fourier Transform analysis of Large Amplitude Oscillatory Shear (LAOS ) experiments were used to differentiate the effect of irradiation and the effect of multiwalled carbon nanotubes (MWCNT) concentration in PP/MWCNT nanocomposites. Alternatively, studies of elastic and viscous non linearities that give shear thinning and thickening or strain softening and hardening were carried out for the same purpose. Using both methods to analyse LAOS data, the conclusion was the same: The influence of MWCNTs is noticed at low/intermediate γo strains (10 - 100 %), whereas the effect of irradiation is rather observed at strains above 100 %. This marks a difference with respect to small amplitude oscillatory flow measurements, which are not valid to distinguish between the respective rheological effects of irradiation and MWCNT in polymer nanocomposites. SEC-MALLS-IR-VI analysis was used to determine the long chain branching degree λ of irradiated polypropylene, but this technique is very difficult to be applied for nanocomposites. Face to this shortcoming, an empirical correlation between λ and the value of the I3/1 plateau when γo tends to infinite, found for irradiated neat PP, was used to evaluate the long chain branching degree of nanocomposites.

Cite this publication as follows:
Fernandez M, Huegun A, Munoz ME, Anton S: Nonlinear oscillatory shear flow as a tool to characterize irradiated polypropylene/MWCNT nanocomposites, Appl. Rheol. 25 (2015) 45154.

Marina Neophytou, Stella Pourgouri, Anton.S Kanellopoulos, Michael Petrou, Ioannis Ioannou, Georgios Georgiou, Andreas Alexandrou
Determination of the rheological parameters of self-compacting concrete matrix using slump flow test

Appl. Rheol. 20:6 (2010) 62402 (12 pages)

The classification of a concrete mixture as self-compacting (SCC) is performed by a series of empirical characterization tests that have been designed to assess not only the flowability of the mixture but also its segregation resistance and filling ability. The objective of the present work is to correlate the rheological parameters of SCC matrix, yield stress and plastic viscosity, to slump flow measurements. The focus of the slump flow test investigation was centered on the fully yielded flow regime and an empirical model relating the yield stress to material and flow parameters is proposed. Our experimental data revealed that the time for a spread of 500 mm which is used in engineering practice as reference for measurement parameters, is an arbitrary choice. Our findings indicate that the non-dimensional final spread is linearly related to the non-dimensional yield-stress. Finally,there are strong indications that the non-dimensional viscosity of the mixture is associated with the non-dimensional final spread as well as the stopping time of the slump flow; this experimental data set suggests an exponential decay of the final spread and stopping time with viscosity.

Cite this publication as follows:
Neophytou M, Pourgouri S, Kanellopoulos A, Petrou M, Ioannou I, Georgiou GC, Alexandrou A: Determination of the rheological parameters of self-compacting concrete matrix using slump flow test, Appl. Rheol. 20 (2010) 62402.

Goretti Goikoetxeaundia, Mercedes Fernandez, Maria Eugenia Munoz, Anton.Santamaria
Rheology applied to investigate roofing membranes: The case of an ecological alternative

Appl. Rheol. 19:6 (2009) 62305 (8 pages)

The viscoelastic performance indicators of a commercial roofing membrane and an ecological bituminous membrane, which contains EVA copolymer from disused greenhouses and filler from landfill, are investigated. Rheological methods reveal as a useful tool to investigate basic and technical aspects of these materials. It is shown that using an extrusion rheometer adapted to measure the flexibility at low temperatures and measuring the tackiness by means of a plate-plate rheometer, constitute basic experiments that help to develop new membranes. Under these premises, it is demonstrated that the ecological membrane is a performing material, whose sole shortcoming is a slightly higher application temperature.

Cite this publication as follows:
Goikoetxeaundia G, Fernandez M, Munoz ME, Santamaria A: Rheology applied to investigate roofing membranes: The case of an ecological alternative, Appl. Rheol. 19 (2009) 62305.


© Applied Rheology 2024