A Systematic Investigation on the Properties of Silica Nanoparticles "Multipoint"-Grafted with Poly(2-acrylamido-2-methylpropanesulfonate- co-acrylic Acid) in Extreme Salinity Brines and Brine-Oil Interfaces

Hyunsu Park; Sehyeong Lim; Jeewon Yang; Chaesu Kwak; Jieun Kim; Jieun Kim; Shin Sik Choi; Chae Bin Kim; Joohyung Lee

doi:10.1021/acs.langmuir.9b03692

A Systematic Investigation on the Properties of Silica Nanoparticles "Multipoint"-Grafted with Poly(2-acrylamido-2-methylpropanesulfonate- co-acrylic Acid) in Extreme Salinity Brines and Brine-Oil Interfaces

Langmuir. 2020 Mar 31;36(12):3174-3183. doi: 10.1021/acs.langmuir.9b03692. Epub 2020 Mar 12.

Authors

Hyunsu Park¹, Sehyeong Lim¹, Jeewon Yang¹, Chaesu Kwak¹, Jieun Kim¹, Jieun Kim¹, Shin Sik Choi², Chae Bin Kim³, Joohyung Lee¹

Affiliations

¹ Department of Chemical Engineering, Myongji University, 116 Myongji-ro, Cheoin-gu, Yongin, Gyeonggi-do 17058, Korea.
² Department of Food and Nutrition, Myongji University, 116 Myongji-ro, Cheoin-gu, Yongin, Gyeonggi-do 17058, Korea.
³ Department of Polymer Science and Engineering, Pusan National University, 2 Busandaehak-ro, Geumjeong-gu, Busan 46241, Korea.

PMID: 32101011
DOI: 10.1021/acs.langmuir.9b03692

Abstract

Nanoparticles (NPs) may have great potential for various subsurface applications, including oil and gas recovery, reservoir imaging, and environmental remediation. One of the important challenges for these downhole applications is to achieve colloidal stability in subsurface media at high salinity and high temperature. It has been previously shown that several functional NPs "multipoint"-grafted with anionic poly(2-acrylamido-2-methyl-1-propanesulfonate-co-acrylic acid; AMPS-co-AA) exhibited remarkable colloidal stabilities in specific environments mimicking the harsh subsurface aquatic media, such as the American Petroleum Institute (API) brine. However, many important properties of such particles, other than the colloidal stabilities, must be studied in a more systematic fashion for a wide range of salt concentrations (C_s). Herein, we investigate various properties of the silica (SiO₂) NPs multipoint-grafted with poly(AMPS-co-AA), SiO₂-g-poly(AMPS-co-AA), in NaCl and CaCl₂ solutions across a range of salinities. The brush behavior of the grafted random copolymers was investigated in both salt solutions from salt-free conditions up to extreme salinities. The particles displayed brine-oil interfacial activity with increasing C_s, stabilizing oil-in-brine emulsions as Pickering emulsifiers. A high internal phase emulsion (HIPE) with an internal oil phase of up to 80 vol % could be formed in CaCl₂ solutions at high C_s, which exhibited gel-like behaviors.