Synthesis and solution behavior of hydrophobically associating polyacrylamide containing capsaicin‐like moieties

Abstract

A novel hydrophobically associating polyacrylamide (PAAHO) of acrylamide, 2-acrylamide-2-methylpropane sulfonate, capsaicin-like monomer N-(4-hydroxy-3-methoxy-benzyl) acrylamide (HMBA), and hydrophobic monomer octadecyl acrylate was synthesized by micellar copolymerization and characterized by fourier transform infrared spectrum, ultraviolet-visible spectrum, and thermogravimetric analysis, respectively. By adjusting various factors, a series of PAAHOs with different block structures were prepared. The hydrophobic association properties were then studied by viscometry and fluorescence spectrometry. Solution behavior was examined with respect to polymer concentration, ionic strength, and temperature. Also, the antibacterial activity was investigated. Results show that initiator amount influenced not only the molecular weight but also the yield and composition of resulting copolymers. PAAHOs possess strong thickening capability, and the hydrophobic association is enhanced as hydrophobe content increases. PAAHOs have excellent viscosity retention in brine solution and exhibit unique rheological behavior including a salt-thickening response. Incorporation of HMBA greatly improves the thermal stability of PAAHO. Moreover, PAAHO is endowed with considerable antibacterial activity against Escherichia coli and Staphylococcus aureus.

Hydrophobically Modified Polyacrylamide Synthesis and Application in Water Treatment

“…Meanwhile, hydrolyzed acrylamide or other hydrophilic comonomers such as acrylic acid and sodium acrylate have been used to increase viscosity of the system 11,13,14 . In addition, sulfonate-containing monomers including vinyl sulfonate, 4-vinyl benzene sulfonate and 2-acrylamido-2-methylpropanesulfonic acid (AMPS) have been used to replace acrylic acid and improve the salt sensitivity of the resulting copolymer [15][16][17] . Moreover, N-vinyl pyrrolidinone (NVP) has sometimes been used to make the resulting copolymer more resistant to base-catalyzed hydrolysis of acrylamide 18,19 .…”

Hydrophobically associating polyacrylamide derivatives with double bond for enhanced solution properties

“…HAPAMs have better stability with respect to salts than unmodified ones, because the enhancement of solution polarity can strengthen the hydrophobic interactions. Moreover, it is possible for HAPAMs to decrease irreversible mechanical degradation since the physical links are disrupted with increasing shear rate but reform with shear rate decreasing . Hydrophobic groups tend to associate together to minimize their exposure to the solvent through intra‐ and intermolecular interactions in aqueous solutions.…”

Rheological evaluation of synthesized template‐hydrophobically modified acrylamide based copolymers in brine

“…Addition of small amount of electrolyte salt to aqueous solution of hydrophobically modified acrylamide‐based copolymers helps to increase the solution polarization, and reinforcing the hydrophobic association . As a result of the hydrophobic groups association, the hydrodynamic size of the polymer increases and their aqueous solutions give attractive rheological properties and, simultaneously, further stability in salinity compared with the unmodified one in addition to the viscosity enhancement . Accordingly, these hydrophobically associating copolymers have a great potential to be used as the mobility controller in reservoirs with a high level of brininess and a high concentration of monovalent and divalent ions …”

“…30,31 As a result of the hydrophobic groups association, the hydrodynamic size of the polymer increases and their aqueous solutions give attractive rheological properties and, simultaneously, further stability in salinity compared with the unmodified one in addition to the viscosity enhancement. 32,33 Accordingly, these hydrophobically associating copolymers have a great potential to be used as the mobility controller in reservoirs with a high level of brininess and a high concentration of monovalent and divalent ions. [34][35][36] Consequently, in recent years, there has been a significant progressive interest about the synthesis and investigation of the solution properties of acrylamide-based copolymers.…”