Effect of Sodium Dodecyl Benzene Sulfonate on Water-Soluble Hydrophobically Associating Polymer Solutions
Notice bibliographique
Résumé
Abstract The dramatic drop in viscosity of polymer solutions raised problems encountered in the processes of enhanced oil recovery (EOR). One of the approaches to solve the problem is to use the shear thickening of the water-soluble hydrophobically associating polymers (HAP) at some shear rate region. The work presented in this paper focused on the effect of sodium dodecycl benzene sulfonate (SDBS) on the rheological behavior of specific-modified HAP aqueous solutions. The viscosities of polymer solutions from dilute, unentangled semi-dilute, to entangled semi-dilute regime were examined as a function of shear rate and concentration of SDBS. It was found that SDBS enhanced the shear thickening in entangled semi-dilute regime. The result was explained in terms of the balance between inter- and intra-chain liaisons and the effect of SDBS on the chain dimensions of the polymer. Fluorescent data showed that SDBS was associated with the hydrophobic groups of the polymer, generating a number of microdomains. These microdomains strengthened the structure viscosity of the polymer solutions. The addition of SDBS to HAP solution also helped to build up a reversible molecular structure and even a temporarily three-dimensional network in aqueous solutions via binding SDBS with hydrophobes of the polymer chains. The network structure resulted in significant increase in viscosity of the polymer solutions. Consequently, the SDBS/HAP systems could be used as thickeners for the fluids used in EOR processes. Introduction Water-soluble polymers are widely used in oilfield operations such as drilling, polymer flooding, chemical flooding and profile modification. Water-soluble hydrophobically associating polymers (HAP) are similar to conventional water-soluble polymers except that a very small portion of hydrophobic comonomer (<1%)(1,2) is incorporated into the polymer backbone. Above the overlap concentration, these polymer chains associate intermolecularly in solution, significantly increasing hydrodynamic size and inherent viscosity. This is of great importance in enhanced oil recovery (EOR). Interactions between HAP and surfactants have been well documented(2–5). Addition of surfactants to polymer solutions can influence the microenviroment of both components. Surfactants associate with the polymer or form micelles, meanwhile the polymer chains tend to reconform to associate with the surfactant. It has been commonly accepted that such systems form hydrophobic microdomains(3,4) through the association of surfactants on hydrophobes of polymers, which cause the polymer chains extension or prevent association of polymer and surfactant by forming micelle around the pendant groups(5). The most obvious change after adding surfactants to HAP is the viscosity(3), which responses to the reconformation of the polymer chains. It is often assumed that the viscosity of plastic fluid consists of structure viscosity and non-structure viscosity(6). Non-structure viscosity is determined by the hydrodynamic size of a single molecule, whereas structure viscosity is controlled by the size and strength of the three-dimensional network. Compared to the non-structure viscosity, structure viscosity is more easily influenced by the shear stress. The polymer solution could be divided into dilute, unentangled semi-dilute, entangled semi-dilute, and high concentration regimes according to the types of HAP molecular associations.
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Scores du classifieur distillé par catégorie (deux têtes)
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,000 | 0,000 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,000 |
| Bibliométrie | 0,000 | 0,000 |
| Études des sciences et des technologies | 0,000 | 0,000 |
| Communication savante | 0,000 | 0,000 |
| Science ouverte | 0,000 | 0,000 |
| Intégrité de la recherche | 0,000 | 0,000 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,001 | 0,000 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
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Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».