Abstract:Compared with other acid gelling agents, amphoteric gelling agents have the advantages of low price and convenient synthesis and can improve the viscosity of acid based on supramolecular effect of gelling agents. Hence, amphoteric gelling agents have wild application prospect in acidizing fracturing field. Two amphoteric gelling agents were synthesized from acrylamide (AM), 2-acrylamide-2-methylpropanesulfonic acid (AMPS), dimethyl diallyl ammonium chloride (DMDAAC) and methacryloyloxyethyl trimethyl ammonium chloride (DMC) by free radical aqueous solution polymerization. The results indicated that acid dissolving time of two amphoteric gelling agents less than 40 min. The viscous acid containing the compound of two amphoteric gelling agents mixed in a certain mass ratio was 39 mPa·s at room temperature (25°C) and 170S-1and was 15 mPa·s at 160°C and 170S-1 after continuous shear for 90min, which demonstrated that the compound had excellent viscosity increasing property, temperature resistance and shear resistance performance