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Thickener for its non-toxic, environmentally friendly, biocompatibility characteristics of lightly cross-linked polyacrylic acid (PAA), a wide range of applications in the biomedical field. In recent years, polyacrylic acid thickener thickening ability, electrical conductivity and high, greatly improve the battery discharge performance and storage performance by the great concern of the people. At home and abroad reported synthetic methods and processes used in the field thickener small, so the study has a good thickening ability and polyacrylic acid thickener electrolyte resistance is important. In this paper, the aqueous solution polymerization and precipitation polymerization prepared thickening ability, electrolyte resistance good polyacrylic acid thickener. (1) aqueous solution of polyacrylic acid thickener, the use of chitosan and maleic anhydride (maleic anhydride), acylation reaction, synthesis of a double bond-containing and water-soluble good N-maleic Chitosan (N -malely chitosan, N-MACH) crosslinker. By infrared analysis (IR), nuclear magnetic resonance (1H NMR) to characterize the structure of the resulting product, the results show that the molecular structure of the structure of the product obtained with theoretical product match. Homemade N-Malay chitosan (N-MACH) as a crosslinking agent, certain neutralization degree of acrylic acid (AA) monomer as the main raw material, ammonium persulfate - sodium bisulfite (APS-NaHSO3) The low-temperature initiator system, polyacrylic acid thickener prepared by aqueous solution free radical polymerization. Research in degree, cause and amount of crosslinking agent, thickener thickening properties, to determine the optimal reaction conditions. By infrared spectroscopy (IR), scanning electron microscopy (SEM), thermogravimetric (TGA) the product of the internal structure, surface structure, thermal properties were characterized. Performance tests show that: neutralized polyacrylic acid thickener viscosity increases with increasing amount of two approximate linear relationship, 0.5% of the thickener viscosities up to 54.3 Pa · s, added at a concentration of 0.005 mol · L-1 of NaCl the viscosity can still reach the 22.4 Pa · s, compared with the the traditional crosslinking agent N, N'-methylene-bis-acrylamide (NMBA) Preparation of the polyacrylic acid has improved greatly. (2) produced in the precipitation polymerization of polyacrylic acid P (AA-co-ODA) thickener C18 hydrophobic chain containing octadecyl acrylate (ODA) as the copolymerizable monomer, acrylic acid (AA) as the main raw material, a polymer of non-ionic Surfactant Hypenner B-246 as dispersing agent, azobisisobutyronitrile heptanenitrile (ABVN), as initiator, was prepared by the precipitation polymerization method with a long chain hydrophobic group of the polyacrylic acid thickener P (AA-co-ODA ). Orthogonal experiment to study the main factors and reaction conditions, to get the ideal synthesis process by univariate analysis. By infrared spectroscopy (IR), scanning electron microscopy (SEM), thermogravimetric (TGA) the product of the internal structure, surface structure, thermal properties were characterized. Performance tests show that: the performance of the neutralized polyacrylic acid, P (AA-co-ODA) thickener for non-Newtonian fluids, the rheological characteristics of the plastic fluid, its viscosity increases with the increase of the amount, 0.5% of the thickener viscosity up to 110 Pa · s, light transmission rate of up to 96.3%, added to a concentration of 0.005 mol · L-1 NaCl 41.2 Pa · s viscosity can be attained, polyacrylic acid and alkaline electrolyte solution with higher conductivity.
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