On the steady shear behavior of hydrophobic fumed silica suspensions in PPG and PEG of low molecular weight
Source abstract
Abstract
Fumed silica with n-hexadecane molecules anchored onto its surface (Aerosil®R816) was dispersed in polypropylene glycol of low molecular weight (PPG400). This system showed a complex steady shear behavior: shear-thickening between two shear-thinning regions. Only shear-thinning behavior was observed when R816 was dispersed in polyethylene glycol of low molecular weight (PEG200). To conciliate both experimental results, Raman spectra of linear hexadecane, n-hexadecane/PPG400, and n-hexadecane/PEG200 mixtures were obtained. Results pointed out a distinct population of conformers could exist in each n-hexadecane-polymer mixture. More specifically, alkyl chains acquired straighter conformation in the PPG400 solvent, while the same alkyl chains showed globular conformations in PEG200.
Source: openalex_inverted_index · Quality: baseline
Research context
OpenAlex topics: Surfactants and Colloidal Systems · Advanced Polymer Synthesis and Characterization · Polymer Nanocomposites and Properties
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
DECEM, Universidad de las Fuerzas Armadas, Sangolquí, Ecuador
Departamento de Física Aplicada II, Universidad de Málaga, Málaga, Spain
Departamento de Ingeniería Mecánica, Térmica y de Fluidos, Universidad de Málaga, Málaga, Spain
Funding
Secretaría de Educación Superior, Ciencia, Tecnología e Innovación
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