Sulfonate lycine type hydrophobic associated polymer and preparation method thereof

Abstract

The present invention discloses a sulfonate lycine type hydrophobic associated polymer and a preparation method thereof. A preparation process of the sulfonate lycine type hydrophobic associated polymer comprises the following steps: firstly, mixing acrylamide and acrylic acid in an aqueous solution; adjusting pH of the system to be around 6 to 8; adding 3-(dimethylamino propyl methacrylamide) propanesulfonate, N-aryl-N-alkyl (methyl) acrylamide and lauryl sodium sulfate and stirring till the solution is clear; and after nitrogen is introduced for deoxidization, adding a photoinitiator azobis (isobutylamidine hydrochloride) for performing polymerization under photoinitiation conditions. The sulfonate lycine type hydrophobic associated polymer integrates the advantages of a two-tailed hydrophobic associated polymer and the advantages of a lycine type polymer, such that the viscosifying property, the temperature resistance, the salt resistance and the hydrolysis resistance of the sulfonate lycine type hydrophobic associated polymer are remarkably improved.

Claims

1. A sulfonate lycine hydrophobic associated polymer, comprising the following structural formula: ##STR00002## wherein in the formula, x, y, m, and n are percentages of first structural units, wherein x is 75% to 85%, m is 0.01% to 1.0%, n is 0.01% to 0.5%, and y is 1-x-m-n; a, b are numbers of second structural units, wherein a is 11, 13 or 15, and b is 1 or 2; R1 is CH.sub.3 or H; and a viscosity average molecular weight of the sulfonate lycine hydrophobic associated polymer is from 100 to 10,000,000.

2. A preparation method of the sulfonate lycine hydrophobic associated polymer according to claim 1, sequentially comprising the following steps: (1) adding acrylamide and acrylic acid to distilled water and stirring uniformly to obtain a first solution, adjusting pH of the first solution to 6-8 with sodium hydroxide to obtain a second solution, adding 3-(dimethylamino propyl methacrylamide) propanesulfonate, hydrophobic monomer N-aryl-N-alkyl (methyl) acrylamide and a surfactant lauryl sodium sulfate to the second solution to obtain a third solution and stirring till the third solution is clear, wherein the acrylamide accounts for 20-21.5 wt %, the acrylic acid accounts for 3.5-5 wt %, the 3-(dimethylamino propyl methacrylamide) propanesulfonate accounts for 0.2-1.0 wt %, the N-aryl-N-alkyl (methyl) acrylamide accounts for 0.2-0.6 wt % and the lauryl sodium sulfate accounts for 0.4-0.8 wt %, wt % refers to the mass fraction of the above substances in a reaction system; (2) introducing nitrogen to the third solution for 15 minutes to remove dissolved oxygen in the third solution to obtain a fourth solution; and (3) adding a photoinitiator to the fourth solution to obtain a fifth solution, and reacting the fifth solution for 3-5 hours at 10-30 C. under a photoinitiation device to obtain viscous white colloid, the viscous white colloid is the sulfonate lycine hydrophobic associated polymer.

3. The preparation method of the sulfonate lycine hydrophobic associated polymer according to claim 2, wherein the photoinitiator is azobis (isobutylamidine hydrochloride).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is an infrared spectrum of a sulfonate lycine type hydrophobic associated polymer.

(2) FIG. 2 is a viscosity-concentration relationship curve of the sulfonate lycine type hydrophobic associated polymer.

(3) FIG. 3 is a viscosity-salinity relationship curve of the sulfonate lycine type hydrophobic associated polymer.

(4) FIG. 4 is a viscosity-aging days relationship curve of the sulfonate lycine type hydrophobic associated polymer.

DETAILED DESCRIPTION OF THE EMBODIMENTS

(5) The present invention is described below in detail according to the drawings and the examples.

I. Preparation of Sulfonate Lycine Type Hydrophobic Associated Polymer

Example 1

(6) weighing acrylamide (10 g), acrylic acid (2.5 g), adding distilled water and stirring uniformly, and adjusting pH to 7; then, adding 3-(dimethylamino propyl methacrylamide) propanesulfonate (0.1 g), N-aryl-N-lauryl methacrylamide and lauryl sodium sulfate (0.3 g), then adding a certain amount of distilled water such that the total mass of the solution reaches 50 g, and stirring till the solution is clear; introducing nitrogen for 15 min to remove dissolved oxygen in water; and adding an initiator v50 (0.1-0.2 wt % of total monomer mass), placing under a photoinitiation device, and reacting for 3 h.

Example 2

(7) weighing acrylamide (10 g), acrylic acid (2.5 g), adding distilled water and stirring uniformly, and adjusting pH to 7; then, adding 3-(dimethylamino propyl methacrylamide) propanesulfonate (0.1 g), N-aryl-N-lauryl methacrylamide (0.1 g) and lauryl sodium sulfate (0.3 g), then adding a certain amount of distilled water such that the total mass of the solution reaches 50 g, and stirring till the solution is clear; introducing nitrogen for 15 min to remove dissolved oxygen in water; and adding an initiator v50 (0.1-0.2 wt % of total monomer mass), placing under a photoinitiation device, and reacting for 3 h.

II. Structural Characterization of Sulfonate Lycine Type Hydrophobic Associated Polymer

(8) FIG. 1 is an infrared spectrum of the polymer synthesized in the example 1.

(9) As can be seen from FIG. 1, a characteristic absorption peak of stretching vibration of NH of primary amide appears at 3408 cm.sup.1; characteristic absorption peaks of antisymmetric stretching vibration and symmetrical stretching vibration of methylene appear at 2981 cm.sup.1 and 2897 cm.sup.1; a characteristic absorption peak of carbonyl appears at 1640 cm.sup.1; a stretching vibration peak of a benzene ring skeleton appears at 1531 cm.sup.1; an in-plane bending vibration absorption peak of methylene appears at 1398 cm.sup.1; a stretching vibration absorption peak of CN in quaternary ammonium salt appears at 1320 cm.sup.1; symmetrical and asymmetric vibration absorption peaks of SO3.sup. appear at 1088 cm.sup.1 and 1049 cm.sup.1; an out-of-plane rocking characteristic peak of primary amide-NH.sub.2 appears at 615 cm.sup.1.

III. Viscosifying Effect Analysis of Sulfonate Lycine Type Hydrophobic Associated Polymer

(10) The polymer synthesized in the example 1 is prepared into polymer solutions of different concentrations. A viscosity-concentration relationship curve of the polymer is measured at room temperature and at a shear rate of 7.34 s.sup.1 (as shown in FIG. 2). As can be seen from FIG. 2, the sulfonate lycine type hydrophobic associated polymer has lower critical association concentration and a good viscosifying effect which reaches 743.7 mPa.Math.s at 2000 mg/L.

IV. Sensitivity to Salt of Sulfonate Lycine Type Hydrophobic Associated Polymer

(11) A study is made for the sensitivity to salt of the polymer synthesized in the example 1. The prepared hydrophobic associated polymer is prepared into a 2000 mg/L polymer solution at different salinities. A change relationship of the apparent viscosity of the polymer solution along with the salinity is measured at room temperature and at a shear rate of 7.34 s.sup.1 (as shown in FIG. 3). As can be seen from FIG. 3, with the increase of NaCl concentration, the apparent viscosity of the polymer presents a trend of decrease-increase-decrease, and the viscosity of the polymer solution can still be maintained at 50% or more under high salinity 120,000 of NaCl, showing a favorable salt resistance effect.

V. Anti-Aging Property of Sulfonate Lycine Type Hydrophobic Associated Polymer

(12) The anti-aging property of the polymer synthesized in the example 1 is evaluated. The prepared hydrophobic associated polymer is prepared into a 2000 mg/L polymer solution, deoxidant is added to the solution and then the mixture is placed in a vial, and sealed. The mixture is aged in a 90 C. oven, and the viscosity of the polymer solution is measured at regular time.

(13) As can be seen from FIG. 4, the viscosity is stable after the polymer solution is aged for about 30 d. At a temperature of 90 C. and a salinity (NaCl) of 1010.sup.4 mg/L, the viscosity of the polymer solution can still be maintained at 60 mPa.Math.s or more, showing good resistance to temperature, salt and aging.