Synthesis And Performance Evaluation Of Hydrophobically Associating Polymers

As an important energy and chemical raw material,petroleum is a limited non-renewable resource.With the massive exploitation of oil,its reserves are falling drastically.In order to meet human needs,new mining technologies must be researched and developed.Partially hydrolyzed polyacrylamides used domestically have a very limited application due to poor temperature and shear resistance.Therefore,in order to improve the temperature-resistance and shear resistance of additives during oil extraction,the synthesis and research of hydrophobically associating polymers have received attention in recent years.In this paper,two types of hydrophobic monomers were synthesized and reacted with monomeric acrylamide(AM)and methacryloyloxyethyltrimethylarmmonium chloride(DMC)to prepare terpolymers,and then we studied the performance of the copolymer.Using 33.0%dimethyl amine solution and allyl chloride as raw materials,the intermediate dimethylallylamine was prepared by halogenation reaction,and then the intermediate and bromohexadecane were used as raw materials,acetone as solvent,and quatemization was carried out.A hydrophobic quaternary ammonium salt monomer,ADMA-16,was prepared by the reaction.A double-tailed hydrophobic monomer PMB-16 was synthesized using phenylethylamine,hexadecane hexadecane and methacryloyl chloride as raw materials.The structures of the two hydrophobic monomers were characterized by FTIR and 'HMNR.The results showed that the experimental product was consistent with the target product.AM and DMC were selected as the reaction materials.Ternary hydrophobic associative polymers were synthesized by free-radical aqueous solution polymerization and hydrophobic monomer copolymerization.They were named PADA and PADM,respectively.The single-factor experiment was used to screen out the best seven synthesis conditions for preparing the polymer.The copolymers were characterized by IR and 'HNMR spectra.The results showed that the copolymers were consistent with the target products.The performance of the polymer PADA as a fracturing fluid drag reducer was tested.The results show that the critical association concentration of the polymer PADA is 0.33%;the polymer PADA has good temperature resistance and salt resistance;High shear and alternating shear experiments show that the polymer has good shear thinning and shear recovery;experimentally found that the polymer solution meets the law of power law fluid,flow index n value is less than 1.0,polymer solution The system is pseudoplastic fluid,and the consistency coefficient K value is large,indicating that the thickening property of the polymer is good;the anti-expansion property of the polymer PADA is good;when the concentration is 0.5%,the anti-expansion rate can reach 82.6%;the polymer solution After the rubber breakage,the residue content was 0 mg/L.There was no solid residue after gel breaking.The gel breaking performance was good.The friction coefficient of the polymer solution was tested at different concentrations.The higher the polymer solution mass fraction,the higher the friction coefficient.The lower the ratio,the more important it is that the hydrophobic association has a certain effect on the resistance reduction rate.The performance of the copolymer PADM cross-linked system for fracturing fluids was tested.The experimental results show that the critical associative concentration of polymer PADM is 0.32%and the polymer solution has resistance to temperature and salt;zirconium acetylacetonate is used as a cross-linking agent,and the optimal crosslinking conditions are selected:cross-linking ratio is 100:0.9,temperature is 60 degrees celsius and the cross-linking pH value is 6.0 to prepare the PADM cross-linking system.The rheological properties of the fracturing fluid system are studied.The experimental results show that the fracturing fluid system can withstand 120 degrees celsius and has a good shear.Shear stability and shear recovery;conforms to the power law model,is pseudoplastic fluid;has better viscoelasticity than HPG cross-linking system,and can well satisfy fracturing fluid carrying Sand requires a low content of broken glue residue and is a low-damage fracturing fluid system.