All-atom molecular dynamics simulation of acrylamide-based triblock copolymers with thermal responsive end blocks in a mixed salt solution containing divalent cations

Design of acrylamide-based thermoresponsive copolymer with potential capability for physical network formation in water: a molecular dynamics study

“…In fact, a large number of the interfacial water molecules in the first hydration shell got almost the same θ and f values. In this regard, the steric hindrance of the copolymer affects the θ and f values as well [18,20]. In addition, this analysis assists to detect the variation of hydrophilicity level of the copolymer blocks with changing the temperature.…”

“…In this study, the simulations of dilute copolymer solutions were implemented using LAMMPS software package developed at the Sandia National Laboratories [25]. Despite the various force fields used to characterize acrylamide-based polymers in aqueous solutions, Polymer Consistent Force Field (PCFF) force field was applied for the simulations because of its accuracy and efficiency [11,18,[26][27][28]. In the simulations, Nose-Hoover thermostat and Berendsen barostat were used to keep the temperature and the pressure constant, respectively.…”

“…Dispersive contribution to the non-bonded interactions was calculated via cut-off distance of 1.2 nm, and the long-range electrostatic contribution was also estimated using particle mesh Ewald (PME) [29]. In our previous work [18], the accuracy and efficiency of the PCFF force field and aforementioned simulation methodology were proved for the acrylamide-based copolymer in an aqueous solution via calculating the polymer physicochemical characteristics and their comparison with experimental results. In addition, the last forty percent of the main current simulations was used for data sampling and statistical analysis.…”

“…Their results showed that the designed copolymer structure led to changing the morphology to microphase-separated structures of inverse tapered block copolymers. In fact, the conformational behavior of a block copolymer in solution depends on the molecular feature of the blocks, i.e., the number of repeating units, fraction of the blocks, and on the interaction parameter between each block and media [17][18][19]. Also, the morphology of block copolymer in a solution can be controlled via changing the type of blocks and optimizing their lengths.…”

Investigation of Polyvinyl Alcohol–Phenolic Aldehyde–Polyacrylamide Gel for the Application in Saline Oil Reservoirs for Profile Modification

“…Therefore, it is necessary to adjust the saltwater content to reduce the viscosity of PAM solution and achieve the conditions suitable for PVA to participate in polymerization. 49 First, 1 wt % PAM solution was prepared by adjusting the different dosages of DI water and formation saltwater (SW). The mass fraction of PAM in PVA/ PAM/HMTA/HQ gelant solution was 0.6%, the mass fraction of PVA was 0.6%, and the cross-linking system (HQ−HMTA) was 0.6%.…”