PHYSICOCHEMICAL AND RHEOLOGICAL CHARACTERIZATION OF COMPLEX COAGULANTS DERIVED FROM WEAK AND MEDIUM ANIONIC POLYMERS AND MEDIUM CATIONIC SURFACTANT

2012 ◽  
Vol 11 (1) ◽  
pp. 29-35
Author(s):  
Constantin Bobirica ◽  
Liliana Bobirica ◽  
Gabriel Dabija ◽  
Mihaela Mihai
Keyword(s):  
Cationic Surfactant ◽  
Rheological Characterization ◽  
Anionic Polymers

Rheological Characterization of Drag-Reducing Cationic Surfactant Solution: Shear and Elongational Viscosities of Dilute Solutions

2003 ◽  
Author(s):  
Yasuo Kawaguchi ◽  
Jinjia Wei ◽  
Bo Yu ◽  
Ziping Feng
Keyword(s):  
Cationic Surfactant ◽  
Surfactant Solution ◽  
Model Parameters ◽  
Rheological Characterization ◽  
Giesekus Model ◽  
Turbulent Drag ◽  
Different Temperatures ◽  
Cetyltrimethyl Ammonium ◽  
Parameter Values

Shear viscosities of one kind of turbulent drag-reducing cationic surfactant solution, Cetyltrimethyl ammonium chloride (CTAC)/Sodium salicylate (NaSal) aqueous solution, were experimentally investigated by use of a stress controlled Reometer. The concentration and temperature of the solution ranged from 50 to 200 ppm and 20 to 40°C, respectively. The Giesekus model was found to fit the measured shear viscosities well for different temperatures and concentrations of the surfactant solution and the model parameter values obtained by fitting were correlated with temperature at certain solution concentrations. The temperature was found to have a large influence on the viscoelasticity of the surfactant solution. By using the model parameters obtained from the correlations, 70 percent of the measured shear viscosities agreed with the prediction by the Giesekus model within ±27.3 percent. The elongational viscosities of CTAC/NaSal surfactant solution were also experimentally investigated by use of an oppositing jet Reometer. The measured data were lower than the prediction by the Giesekus model.

Rheological characterization of tack and viscoelasticity of compositions of crepe coating used in the Yankee dryer

TAPPI Journal ◽  
2019 ◽  
Vol 18 (11) ◽  
pp. 641-649
Author(s):  
JOSHUA OMAMBALA ◽  
CARL MCINTYRE
Keyword(s):  
Normal Force ◽  
Weight Ratio ◽  
Good Combination ◽  
Rheological Characterization ◽  
Nonlinear Viscoelastic ◽  
Coating Composition ◽  
Linear And Nonlinear ◽  
Work Done ◽  
Tissue Production

The vast majority of tissue production uses creping to achieve the required set of properties on the base sheet. The Yankee coating helps to develop the desired crepe that in turn determines properties such as bulk and softness. The adhesion of the sheet to the Yankee surface is a very important characteristic to consider in achieving the desired crepe. The coating mix usually consists of the adhesive, modifier, and release. A good combination of these components is essential to achieving the desired properties of the tissue or towel, which often are determined by trials on the machine that can be time consuming and lead to costly rejects. In this paper, five compositions of an industrial Yankee coating adhesive, modifier, and release were examined rheologically. The weight ratio of the adhesive was kept constant at 30% in all five compositions and the modifier and release ratios were varied. The normal force and work done by the different compositions have been shown at various temperatures simulating that of the Yankee surface, and the oscillatory test was carried out to explain the linear and nonlinear viscoelastic characteristic of the optimal coating composition.

CHEMICAL AND RHEOLOGICAL CHARACTERIZATION OF A VEGETABLE-BASED EMULSION

2019 ◽  
Author(s):  
Luiz Eduardo Rodrigues Vieira ◽  
Leonardo Rosa Ribeiro da Silva ◽  
Felipe Chagas Rodrigues de Souza ◽  
Wisley Sales ◽  
Álisson Rocha Machado
Keyword(s):  
Rheological Characterization

RHEOLOGICAL CHARACTERIZATION OF PERUVIAN COPPER ORE SLURRIES

2020 ◽  
Author(s):  
Joel López Bonilla ◽  
Cesar Celis ◽  
Danmer Maza
Keyword(s):  
Rheological Characterization ◽  
Copper Ore

scholarly journals Toward Physicochemical and Rheological Characterization of Different Injectable Hyaluronic Acid Dermal Fillers Cross-Linked with Polyethylene Glycol Diglycidyl Ether

Polymers ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 948
Author(s):  
Nicola Zerbinati ◽  
Sabrina Sommatis ◽  
Cristina Maccario ◽  
Maria Chiara Capillo ◽  
Giulia Grimaldi ◽  
...  
Keyword(s):  
Hyaluronic Acid ◽  
Polyethylene Glycol ◽  
Biological Activities ◽  
Diglycidyl Ether ◽  
Dermal Filler ◽  
Cross Linking ◽  
Matrix Structure ◽  
Dermal Fillers ◽  
Rheological Characterization

(1) Background: Injectable hyaluronic acid (HA) dermal fillers are used to restore volume, hydration and skin tone in aesthetic medicine. HA fillers differ from each other due to their cross-linking technologies, with the aim to increase mechanical and biological activities. One of the most recent and promising cross-linkers is polyethylene glycol diglycidyl ether (PEGDE), used by the company Matex Lab S.p.A., (Brindisi, Italy) to create the HA dermal filler PEGDE family. Over the last few years, several studies have been performed to investigate the biocompatibility and biodegradability of these formulations, but little information is available regarding their matrix structure, rheological and physicochemical properties related to their cross-linking technologies, the HA content or the degree of cross-linking. (2) Methods: Seven different injectable HA hydrogels were subjected to optical microscopic examination, cohesivity evaluation and rheological characterization in order to investigate their behavior. (3) Results: The analyzed cross-linked dermal fillers showed a fibrous “spiderweb-like” matrix structure, with each medical device presenting different and peculiar rheological features. Except for HA non cross-linked hydrogel 18 mg/mL, all showed an elastic and cohesive profile. (4) Conclusions: The comparative analysis with other literature works makes a preliminary characterization of these injectable medical devices possible.

scholarly journals Rheological Characterization of a Concentrated Phosphate Slurry

Fluids ◽  
2021 ◽  
Vol 6 (5) ◽  
pp. 178
Author(s):  
Souhail Maazioui ◽  
Abderrahim Maazouz ◽  
Fayssal Benkhaldoun ◽  
Driss Ouazar ◽  
Khalid Lamnawar
Keyword(s):  
Flow Behavior ◽  
Continuous Phase ◽  
Raw Material ◽  
Rheological Characterization ◽  
Phosphate Ore ◽  
Insoluble Particles ◽  
Experimental Protocols ◽  
Solid Liquid

Phosphate ore slurry is a suspension of insoluble particles of phosphate rock, the primary raw material for fertilizer and phosphoric acid, in a continuous phase of water. This suspension has a non-Newtonian flow behavior and exhibits yield stress as the shear rate tends toward zero. The suspended particles in the present study were assumed to be noncolloidal. Various grades and phosphate ore concentrations were chosen for this rheological investigation. We created some experimental protocols to determine the main characteristics of these complex fluids and established relevant rheological models with a view to simulate the numerical flow in a cylindrical pipeline. Rheograms of these slurries were obtained using a rotational rheometer and were accurately modeled with commonly used yield-pseudoplastic models. The results show that the concentration of solids in a solid–liquid mixture could be increased while maintaining a desired apparent viscosity. Finally, the design equations for the laminar pipe flow of yield pseudoplastics were investigated to highlight the role of rheological studies in this context.

Sign in / Sign up

Export Citation Format

Share Document