HPAM‐g‐PEOPPO: Rheological modifiers in aqueous media of high temperature and high ionic strength

Abstract

Partially hydrolyzed polyacrylamide (HPAM) is widely used as thickener in enhanced oil recovery (EOR), but the high temperature and salinity of oil reservoirs can reduce the viscosity and lead to polymer precipitation. To improve the performance of HPAM in high‐salinity and high‐temperature environments, the responsive amino‐terminated poly(ethylene oxide‐co‐propylene oxide) (PEOPPO) (EO/PO = 19/03) was grafted onto a HPAM backbone. The copolymers were prepared in water using 1‐ethyl‐3‐[3‐(dimethylamino)‐propyl]carbodiimide hydrochloride/N‐hydroxysuccinimide (EDC/NHS) as activators. Structural characterization was performed by 1H NMR and Fourier transform infrared (FTIR) and the responsive behavior was investigated by UV–Vis and rheology. Spectroscopic analyses confirmed that copolymers were successfully synthesized. UV–Vis showed that copolymers have combined salt and thermoresponsive character. Rheology in saline medium (ionic strength = 3.75 mol.L−1) revealed that, contrary to unmodified HPAM, HPAM‐g‐PEOPPO have thermothickening behavior and also higher viscosity than HPAM at 70 °C, suggesting the utilization of these copolymers as rheological modifiers under harsh conditions of temperature and salinity, such as the ones found in EOR applications. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47453.

Tannic Acid-Modified Poly(acrylamide-co-acrylic acid): A Versatile Approach for Aqueous Viscosity Modulation

“…The 1 H NMR spectra of HPAM, TA, TA0.4, TA4, and TA10 are shown in Figure . The spectra exhibit typical −CH 2 (1) signals ranging from 1.65 to 1.76 ppm and −CH (2) signals ranging from 2.23 to 2.33 ppm, which are attributed to the backbone of the polymer . Additionally, in the spectra of pure TA, TA0.4, TA4, and TA10, a relevant signal from the aromatic −CH is observed at 7.08 ppm (3), consistent with the findings of Jing et al The relative percentage of acrylic acid in the polymer was determined from the integration of the 1 H NMR spectra.…”

“…The signals ranging from 2.23 to 2.33 ppm, which are attributed to the backbone of the polymer. 28 Additionally, in the spectra of pure TA, TA0.4, TA4, and TA10, a relevant signal from the aromatic −CH is observed at 7.08 ppm (3), consistent with the findings of Jing et al 27 The relative percentage of acrylic acid in the polymer was determined from the integration of the 1 H NMR spectra. The integration of the signal of the protons in the methylene close to the carboxylic acid was divided by the sum of this signal and the integration of the protons close to the carbonyl of the amide.…”

Remoção De Cromo Hexavalente Presente Em Soluções Sintéticas Diluídas Empregando Carvão Ativado Comercial E Carvão Vegetal Produzido a Partir Da Casca De Arroz

“…Ainda, no espectro do copolímero houve alargamento dos picos referentes à cadeia de HPAM, com o deslocamento na faixa de 1,40-1,95 ppm para os grupos -CH 2 da cadeia de HPAM, enquanto que os grupos -CH da cadeia principal estão em 1,96-2,85 ppm. (De Vos et al, 1994;Karakasyan et al, 2008;Mojarradi, 2010;D'este et al, 2014;Gupta et al, 2015;Marques et al, 2018;De Lima et al, 2019). (Li et al, 2017).…”

“…Por fim, o produto foi liofilizado. A síntese foi feita seguindo as proporções (Marques et al, 2018;De Lima et al, 2019) HPAM e dos grupos CH 3 pertencentes aos meros de óxido de propileno da PEOPPO (Atta et al, 2011), utilizando a seguinte equação (Equação 1):…”

Hydrophobic Dendritic Modification of a Poly(acrylamide-co-acrylic Acid) Copolymer with Behera′s Amine as Viscous Agent

“…These spectra display typical signals for −CH 2 (1) groups ranging from 1.6 to 1.8 ppm and −CH (2) groups ranging from 1.9 to 2.3 ppm, attributed to the polymer backbone. 28 Additionally, in the BA-HPAM spectra, BA exhibits three distinct signals: one at 1.3 ppm corresponding to the −CH 3 (3) groups, another at 3.6 ppm corresponding to −CH 2 (4), and a third at 3.7 ppm corresponding to another −CH 2 (5), differing in their molecular environment. Furthermore, the −CH 3 groups may overlap with the polymer chain due to a signal shift.…”