Rheological Properties in Aqueous Solution for Hydrophobically Modified Polyacrylamides Prepared in Inverse Emulsion Polymerization

Abstract

Inverse emulsion polymerization technique was employed to synthesize hydrophobically modified polyacrylamide polymers with hydrophobe contents near to feed composition. Three different structures were obtained: multisticker, telechelic, and combined. NDimethyl-acrylamide (DMAM), n-dodecylacrylamide (DAM), and n-hexadecylacrylamide (HDAM) were used as hydrophobic comonomers. The effect of the hydrophobe length of comonomer, the initial monomer, and surfactant concentrations on shear viscosity was studied. Results show that the molecular weight of copolymer increases with initial monomer concentration and by increasing emulsifier concentration it remained almost constant. Shear viscosity measurements results show that the length of the hydrophobic comonomer augments the hydrophobic interactions causing an increase in viscosity and that the polymer thickening ability is higher for combined polymers.

Application of Hybrid Polymer Containing POSS as High-Temperature- and High-Salt-Resistant Fluid Loss Additive in Water-Based Drilling Fluids

“…The fluid loss additive PAAD was prepared to refer to the reverse emulsion polymerization method , (Figure ). First, 5 g of OV-POSS was dissolved in 75 mL of toluene.…”

Microflow Mechanism of Oil Displacement by Viscoelastic Hydrophobically Associating Water-Soluble Polymers in Enhanced Oil Recovery

“…It also can tolerate high salinities [23,24]. The viscosity can increase rapidly when the concentration is larger than the critical association concentration because of the network structure formed by the association of molecules, as shown in Figure 2 [25]. HAWP have been tested to be shear-stable at high flow rates.…”

Preparation of ammonium polyacrylate thickener via inverse emulsion polymerization: paste forming ability and rheological property

“…through solution polymerization, 25,26 emulsion polymerization, [27][28][29] and inverse emulsion polymerization. [30][31][32] Among them, inverse emulsion polymerization is the most commonly used method to synthesize thickeners, because the product prepared by this method has a high paste rate. For example, in order to prepare a highly stable acrylamide based thickener, Rivera et al 33 use Isopar K/Exxol D40 as the continuous phase, acrylamide, acrylic acid (AA), and ammonium acrylate as the comonomers, Span 80/Hypermer 1083 as the emulsifier, the polymer of alkyl methacrylate and methacrylic acid as the dispersant, N,N'-methylene-bis-acrylamide (MBA) as the crosslinking agent, sodium hypophosphite as the branching agent, and sodium bromate/sodium pyrosulfite as the redox initiator system.…”

“…At present, researchers have prepared polyacrylic acid synthetic thickeners with different structures through solution polymerization, 25,26 emulsion polymerization, 27–29 and inverse emulsion polymerization. 30–32 Among them, inverse emulsion polymerization is the most commonly used method to synthesize thickeners, because the product prepared by this method has a high paste rate. For example, in order to prepare a highly stable acrylamide based thickener, Rivera et al.…”