Polymer gel temporary plugging agent as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of temporary plugging agents, and particularly relates to a polymer gel temporary plugging agent and a preparation method and application thereof. The polymer gel temporary plugging agent provided by the invention is a novel temporary plugging agent taking a ternary comb polymer of sodium p-styrenesulfonate, alpha-olefin and 2-(6-isocyanate hexylamine amide)-6-methyl-4-[h]-pyrimidone as a main agent. The temporary plugging agent has the advantages of good thermal stability and water solubility, strong tensile strength and viscosity capacity, excellent temporary plugging performance and high recovery rate after washing, and has the advantages of obvious fracture growth effect and low formation damage.

Description

Technical Field

[0001] The present invention belongs to the technical field of temporary plugging agents, and particularly relates to a polymer gel temporary plugging agent, a preparation method thereof, and an application thereof. Background Art

[0002] With the continuous development of oilfield exploitation, the development stage of medium and high water cut in old oilfields has arrived, and the proportion of low-yield and low-efficiency wells has gradually increased, bringing new challenges to oilfield production and exploitation. In order to improve the exploitation efficiency, refracturing technology has become an important potential tapping means. However, traditional refracturing technology has problems such as poor well selection conditions and poor potential tapping effects. To overcome these problems, diversion fracturing technology has emerged as the times require. This technology introduces a temporary plugging agent during the fracturing process to temporarily plug both sides and the front end of the fracture, increase the net pressure in the fracture, force the formation of a new branched fracture system, effectively communicate the unexploited "dead oil area", and thus increase the single-well output. This technology has been studied and applied in many oilfields in China.

[0003] However, the main components of existing temporary plugging agents are mostly starch, which has poor water solubility, low molecular weight, insufficient compressive strength, and the plugging removal time cannot be accurately controlled. Therefore, it cannot meet the precise requirements for fracturing pressure and plugging removal timing. This limits the application scope and efficiency of diversion fracturing technology. To solve these problems, this patent proposes a new type of temporary plugging agent mainly composed of a ternary comb-shaped polymer of sodium styrene sulfonate, α-olefin, and 2-(6-isocyanatohexylamino amide)-6-methyl-4-[h]-pyrimidinone. This temporary plugging agent has the advantages of good thermal stability and water solubility, strong tensile strength and viscosity ability, excellent temporary plugging performance, and high recovery rate after water washing. The fracturing growth effect is obvious, and the formation damage is low. This technological innovation is expected to overcome the limitations of traditional temporary plugging agents, improve the performance and controllability of diversion fracturing technology, and provide a more sustainable and efficient solution for oilfield exploitation.

[0004] Therefore, it is necessary to develop new temporary plugging agents to overcome the limitations of traditional temporary plugging agents, improve the performance and controllability of diversion fracturing technology, and provide a more sustainable and efficient solution for oilfield exploitation. Summary of the Invention

[0005] To solve the deficiencies of the existing technology, the present invention provides a polymer gel temporary plugging agent, a preparation method thereof, and an application thereof. This polymer gel temporary plugging agent is a new type of temporary plugging agent mainly composed of a ternary comb-shaped polymer of sodium styrene sulfonate, α-olefin, and 2-(6-isocyanatohexylamino amide)-6-methyl-4-[h]-pyrimidinone. This temporary plugging agent has the advantages of good water solubility, strong tensile strength and viscosity ability, excellent temporary plugging performance, and high recovery rate after water washing. The fracturing growth effect is obvious, and the formation damage is low.

[0006] The technical solution provided by the present invention is as follows:

[0007] A polymer gel temporary plugging agent comprises the following components in weight percentage: 55% - 80% of a comb-shaped structure polymer main agent, 5% - 10% of 500 - 800 mesh ultra-fine calcium carbonate powder, 5% - 10% of 100 - 300 mesh mica powder, 5 - 15% of plant fiber, and 5 - 10% of ceramic fiber. The comb-shaped structure polymer main agent is polymerized from sodium styrene sulfonate, α-olefin, and 2-(6-isocyanatohexylamido)-6-methyl-4-[h]-pyrimidinone as monomers.

[0008] The polymer provided by the above technical solution contains sodium styrene sulfonate, α-olefin, and 2-(6-isocyanatohexylamido)-6-methyl-4-[h]-pyrimidinone. Among them, a relatively high proportion of sodium styrene sulfonate ensures the water solubility of the polymer, effectively reduces the sensitivity of the comb-shaped polymer molecules to metal salt ions, and significantly improves the salt resistance performance. Even in a solution with a relatively high salinity, it can still maintain good plugging performance. At the same time, using the copolymer of sodium styrene sulfonate and α-olefin as the main chain helps to improve the stability and rigidity of the polymer chain, thus having a relatively high pressure-bearing capacity. In addition, introducing 2-(6-isocyanatohexylamido)-6-methyl-4-[h]-pyrimidinone units into the polymer side chain to form a comb-shaped polymer, which improves the water absorption and swelling ability of the polymer. Combining with the hydrogen bonds provided by the pyrimidine units, this polymer gel also has good self-healing ability and bonding ability, thus achieving good plugging of cracks.

[0009] Specifically, the 500 - 800 mesh ultra-fine calcium carbonate powder is selected from the prior art and can be purchased.

[0010] Specifically, the 100 - 300 mesh mica powder is selected from the prior art and can be purchased.

[0011] Specifically, the plant fiber is selected from any one of hemp and wheat straws, cotton fibers, walnut shells, or coconut shells, is selected from the prior art, can be purchased, and can play a role in bridging and connecting, increasing the strength of the temporary plugging agent.

[0012] Specifically, the ceramic fiber is selected from the prior art and can be purchased.

[0013] The sizes of the above components are complementary, and the combined use can improve the temporary plugging ability of the temporary plugging agent for different cracks, improve the strength of the temporary plugging agent, and play an overall role.

[0014] Specifically, the α-olefin is pentaerythritol allyl ether, and the structural formula of the comb-shaped structure polymer main agent is as follows:

[0015]

[0016] Specifically, the α-olefin is acrylamide, and the structural formula of the comb-shaped structure polymer main agent is as follows:

[0017]

[0018] In the above technical solution:

[0019] The present invention also provides a preparation method of the above polymer gel temporary plugging agent, comprising the following steps:

[0020] 1) Prepare a comb-shaped polymer main agent;

[0021] 2) Mix each component according to the amount in the formula to obtain it.

[0022] Specifically, in step 1), the preparation method of the comb-shaped polymer main agent comprises the following steps:

[0023] S1: Prepare a sodium styrene sulfonate-α-olefin binary copolymer by carrying out an alkenyl radical reaction on sodium styrene sulfonate and α-olefin;

[0024] S2: Carry out a graft reaction on the active hydrogen in the side chain of the binary copolymer obtained in step 1) with 2-(6-isocyanatohexylamino amide)-6-methyl-4-[h]-pyrimidinone to prepare the comb-shaped polymer main agent.

[0025] Specifically, the specific steps of step S1 are as follows: Add sodium styrene sulfonate, α-olefin, and catalyst I into deionized aqueous solution, mix evenly, heat to 100°C - 140°C, react for 4 - 10 hours, and after the reaction is completed, cool and dry to obtain a sodium styrene sulfonate-α-olefin binary copolymer.

[0026] Specifically, catalyst I includes an oxidizing agent and a reducing agent added successively, and the molar ratio of the oxidizing agent to the reducing agent is 3:(2 - 3). The oxidizing agent is selected from any one of hydrogen peroxide or persulfate; the reducing agent is selected from any one of bisulfite, sulfite, or thiosulfate.

[0027] Specifically, the specific steps of step S2 are as follows: Dissolve the sodium styrene sulfonate-α-olefin binary copolymer and 2-(6-isocyanatohexylamino amide)-6-methyl-4-[h]-pyrimidinone in solvent I, add a trace amount of basic catalyst II, mix evenly, react at 20°C - 60°C for 10 - 16 hours, and after the reaction is completed, cool, dry, and pulverize to obtain the comb-shaped polymer main agent.

[0028] Specifically, solvent I is selected from any one or more of N,N-dimethylformamide, methanol, ethanol, or dimethyl sulfoxide.

[0029] Specifically, the basic catalyst is selected from any one or more of sodium hydroxide or potassium hydroxide.

[0030] Specifically, the molar ratio of sodium styrene sulfonate, α-olefin, catalyst I, 2-(6-isocyanatohexylaminoamide)-6-methyl-4-[h]-pyrimidinone, and basic catalyst II is (1 - 1.3):(1 - 1.5):(0.01 - 0.03):(0.2 - 0.5):(0.01 - 0.03).

[0031] The present invention also provides an application of the polymer gel temporary plugging agent as a temporary plugging agent for oil and gas development.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] 1) The temporary plugging agent provided by the present invention has the advantages of good water solubility, strong tensile strength and viscosity ability, excellent temporary plugging performance, and high recovery rate after water washing. The fracturing growth effect is obvious and the formation damage is low.

[0034] 2) The temporary plugging agent provided by the present invention is composed of a polymer main agent and additive particles of different sizes, including 5% - 10% of 500 - 800 mesh ultrafine calcium carbonate powder, 5% - 10% of 100 - 300 mesh mica powder, 5 - 15% of plant fiber, and 5 - 10% of ceramic fiber, which further enhances the plugging ability of the additive for cracks of different sizes. The fiber component can play a bridging connection role and increase the strength of the temporary plugging agent.

[0035] 3) After the main agent of the temporary plugging agent provided by the present invention is washed by formation water for a long time, the core has a high permeability, good selective plugging and plugging removal performance, and reduces the damage to the formation. Specific Embodiments

[0036] The principles and features of the present invention are described below. The examples given are only used to explain the present invention and are not intended to limit the scope of the present invention.

[0037] Example 1

[0038] First, 0.1 mol of sodium styrene sulfonate, 0.15 mol of pentaerythritol allyl ether, and 0.001 mol of catalyst I (0.0006 mol of hydrogen peroxide and 0.0004 mol of sodium bisulfite) are added to 200 mL of deionized water solution, mixed evenly, heated to 100 °C, and reacted for 10 hours. After the reaction is completed, it is cooled and dried to obtain a sodium styrene sulfonate-α-olefin binary copolymer. Subsequently, the sodium styrene sulfonate-α-olefin binary copolymer and 0.05 mol of 2-(6-isocyanatohexylaminoamide)-6-methyl-4-[h]-pyrimidinone are dissolved in N,N-dimethylformamide, 0.003 mol of sodium hydroxide is added, mixed evenly, and reacted at 20 °C for 16 hours. After the reaction is completed, it is cooled, dried, and pulverized to obtain a comb-shaped polymer powder.

[0039] Subsequently, 5.5 g of comb-shaped polymer powder, 1 g of 500-mesh ultrafine calcium carbonate powder, 1 g of 100-mesh mica powder, 1.5 g of ramie and wheat straw, and 1 g of ceramic fiber were weighed and mixed evenly to obtain a polymer gel temporary plugging agent.

[0040] Example 2

[0041] The synthesis steps of the comb-shaped polymer powder were the same as those in Example 1. 6.5 g of comb-shaped polymer powder, 0.5 g of 500-mesh ultrafine calcium carbonate powder, 1 g of 100-mesh mica powder, 1.5 g of ramie and wheat straw, and 0.5 g of ceramic fiber were weighed and mixed evenly to obtain a polymer gel temporary plugging agent.

[0042] Example 3

[0043] The synthesis steps of the comb-shaped polymer powder were the same as those in Example 1. 8 g of comb-shaped polymer powder, 0.5 g of 500-mesh ultrafine calcium carbonate powder, 0.5 g of 100-mesh mica powder, 0.5 g of ramie and wheat straw, and 0.5 g of ceramic fiber were weighed and mixed evenly to obtain a polymer gel temporary plugging agent.

[0044] Example 4

[0045] First, 0.1 mol of sodium styrene sulfonate, 0.15 mol of acrylamide, and 0.001 mol of catalyst I (0.0005 mol of hydrogen peroxide and 0.0005 mol of sodium bisulfite) were added to 200 mL of deionized water solution, mixed evenly, heated to 120 °C, and reacted for 6 hours. After the reaction was completed, it was cooled and dried to obtain sodium styrene sulfonate-α-olefin binary copolymer. Subsequently, the sodium styrene sulfonate-α-olefin binary copolymer and 0.05 mol of 2-(6-isocyanatohexylamide)-6-methyl-4-[h]-pyrimidinone were dissolved in dimethyl sulfoxide, 0.003 mol of potassium hydroxide was added, mixed evenly, and reacted at 40 °C for 13 hours. After the reaction was completed, it was cooled, dried, and pulverized to obtain comb-shaped polymer powder.

[0046] Subsequently, 5.5 g of comb-shaped polymer powder, 1 g of 500-mesh ultrafine calcium carbonate powder, 1 g of 100-mesh mica powder, 1.5 g of cotton fiber, and 1 g of ceramic fiber were weighed and mixed evenly to obtain a polymer gel temporary plugging agent.

[0047] Example 5

[0048] The synthesis steps of the comb-shaped polymer powder were the same as those in Example 4. 6.5 g of comb-shaped polymer powder, 0.5 g of 500-mesh ultrafine calcium carbonate powder, 1 g of 100-mesh mica powder, 1.5 g of cotton fiber, and 0.5 g of ceramic fiber were weighed and mixed evenly to obtain a polymer gel temporary plugging agent.

[0049] Example 6

[0050] The synthesis steps of the comb-shaped polymer powder are the same as those in Example 4. Weigh 8 g of the comb-shaped polymer powder, 0.5 g of 500-mesh ultra-fine calcium carbonate powder, 0.5 g of 100-mesh mica powder, 0.5 g of cotton fiber, and 0.5 g of ceramic fiber, and mix them evenly to obtain the polymer gel temporary plugging agent.

[0051] Example 7

[0052] First, add 0.12 mol of sodium styrene sulfonate, 0.13 mol of acrylamide, and 0.003 mol of Catalyst I (0.002 mol of hydrogen peroxide and 0.001 mol of sodium thiosulfate) to 200 mL of deionized aqueous solution, mix them evenly, heat up to 140 °C, and react for 4 hours. After the reaction is completed, cool and dry to obtain the sodium styrene sulfonate-α-olefin binary copolymer. Subsequently, dissolve the sodium styrene sulfonate-α-olefin binary copolymer and 0.05 mol of 2-(6-isocyanatohexylamide)-6-methyl-4-[h]-pyrimidinone in dimethyl sulfoxide, add 0.003 mol of potassium hydroxide, mix them evenly, and react at 60 °C for 10 hours. After the reaction is completed, cool, dry, and pulverize to obtain the comb-shaped polymer powder.

[0053] Subsequently, weigh 5.5 g of the comb-shaped polymer powder, 1 g of 500-mesh ultra-fine calcium carbonate powder, 1 g of 100-mesh mica powder, 1.5 g of walnut shell, and 1 g of ceramic fiber, and mix them evenly to obtain the polymer gel temporary plugging agent.

[0054] Example 8

[0055] The synthesis steps of the comb-shaped polymer powder are the same as those in Example 7. Weigh 6.5 g of the comb-shaped polymer powder, 0.5 g of 500-mesh ultra-fine calcium carbonate powder, 1 g of 100-mesh mica powder, 1.5 g of walnut shell, and 0.5 g of ceramic fiber, and mix them evenly to obtain the polymer gel temporary plugging agent.

[0056] Example 9

[0057] The synthesis steps of the comb-shaped polymer powder are the same as those in Example 7. Weigh 8 g of the comb-shaped polymer powder, 0.5 g of 500-mesh ultra-fine calcium carbonate powder, 0.5 g of 100-mesh mica powder, 0.5 g of walnut shell, and 0.5 g of ceramic fiber, and mix them evenly to obtain the polymer gel temporary plugging agent.

[0058] Example 10

[0059] First, 0.13 mol of sodium styrene sulfonate, 0.1 mol of pentaerythritol allyl ether, and 0.0015 mol of catalyst I (0.001 mol of hydrogen peroxide and 0.0005 mol of sodium thiosulfate) were added to 200 mL of deionized aqueous solution, mixed evenly, heated to 120 °C, and reacted for 6 hours. After the reaction, it was cooled and dried to obtain a sodium styrene sulfonate-α-olefin binary copolymer. Subsequently, the sodium styrene sulfonate-α-olefin binary copolymer and 0.03 mol of 2-(6-isocyanatohexylamide)-6-methyl-4-[h]-pyrimidinone were dissolved in ethanol, 0.002 mol of potassium hydroxide was added, mixed evenly, and reacted at 60 °C for 10 hours. After the reaction, it was cooled, dried, and pulverized to obtain a comb-shaped polymer powder.

[0060] Subsequently, 5.5 g of the comb-shaped polymer powder, 1 g of 500-mesh ultra-fine calcium carbonate powder, 1 g of 100-mesh mica powder, 1.5 g of coconut shell, and 1 g of ceramic fiber were weighed and mixed evenly to obtain a polymer gel temporary plugging agent.

[0061] Example 11

[0062] The synthesis steps of the comb-shaped polymer powder were the same as those in Example 10. 6.5 g of the comb-shaped polymer powder, 0.5 g of 500-mesh ultra-fine calcium carbonate powder, 1 g of 100-mesh mica powder, 1.5 g of coconut shell, and 0.5 g of ceramic fiber were weighed and mixed evenly to obtain a polymer gel temporary plugging agent.

[0063] Example 12

[0064] The synthesis steps of the comb-shaped polymer powder were the same as those in Example 10. 8 g of the comb-shaped polymer powder, 0.5 g of 500-mesh ultra-fine calcium carbonate powder, 0.5 g of 100-mesh mica powder, 0.5 g of coconut shell, and 0.5 g of ceramic fiber were weighed and mixed evenly to obtain a polymer gel temporary plugging agent.

[0065] Example 13

[0066] First, 0.13 mol of sodium styrene sulfonate, 0.1 mol of pentaerythritol allyl ether, and 0.0015 mol of catalyst I (0.001 mol of hydrogen peroxide and 0.0005 mol of sodium thiosulfate) were added to 200 mL of deionized aqueous solution, mixed evenly, heated to 120 °C, and reacted for 6 hours. After the reaction, it was cooled and dried to obtain a sodium styrene sulfonate-α-olefin binary copolymer. Subsequently, the sodium styrene sulfonate-α-olefin binary copolymer and 0.01 mol of 2-(6-isocyanatohexylamide)-6-methyl-4-[h]-pyrimidinone were dissolved in methanol, 0.001 mol of potassium hydroxide was added, mixed evenly, and reacted at 60 °C for 10 hours. After the reaction, it was cooled, dried, and pulverized to obtain a comb-shaped polymer powder.

[0067] Subsequently, 5.5 g of comb-shaped polymer powder, 1 g of 500-mesh ultrafine calcium carbonate powder, 1 g of 100-mesh mica powder, 1.5 g of coconut shell, and 1 g of ceramic fiber were weighed and mixed evenly to obtain a polymer gel temporary plugging agent.

[0068] Example 14

[0069] The synthesis steps of the comb-shaped polymer powder were the same as those in Example 13. 6.5 g of comb-shaped polymer powder, 0.5 g of 500-mesh ultrafine calcium carbonate powder, 1 g of 100-mesh mica powder, 1.5 g of coconut shell, and 0.5 g of ceramic fiber were weighed and mixed evenly to obtain a polymer gel temporary plugging agent.

[0070] Example 15

[0071] The synthesis steps of the comb-shaped polymer powder were the same as those in Example 13. 8 g of comb-shaped polymer powder, 0.5 g of 500-mesh ultrafine calcium carbonate powder, 0.5 g of 100-mesh mica powder, 0.5 g of coconut shell, and 0.5 g of ceramic fiber were weighed and mixed evenly to obtain a polymer gel temporary plugging agent.

[0072] A 10 g / L temporary plugging agent aqueous solution was prepared with formation water. The adhesion ability of the temporary plugging agent was evaluated by measuring the adhesion force between the temporary plugging agent and the artificial core fracture surface under a pressure-bearing state. The temporary plugging agent aqueous solution was coated on the core fracture surface (7 cm long and about 2.5 cm in diameter), and a 4 MPa confining pressure was applied to the core using KTA-7000, and the external force when the upper and lower fracture surfaces of the core were separated was measured. The test results are shown in Tables 1 and 2.

[0073] Table 1 Composition of simulated formation water (g / L)

[0074] <![CDATA[CaCl 2 > <![CDATA[MgCl 2 ·6H 2 O]]> <![CDATA[Sodium 2 Sulfur Oxide 4 > <![CDATA[NaHCO 3 > NaCl KCl KI KBr 27.95 8.59 0.148 0.102 170.68 0.24 0.01 0.12

[0075] Table 2 Adhesion strength between the temporary plugging agent and the core wall under a 4 MPa confining pressure

[0076] Example Ring crush strength / MPa External force / N Fracture condition <![CDATA[Strength σ g-w <σ]]> 1 4 8.9 Self-fracture <![CDATA[σ g-w >σ]]> 2 4 9.9 Self-fracture <![CDATA[σ g-w >σ]]> 3 4 11.5 Self-fracture <![CDATA[σ g-w >σ]]> 4 4 7.8 Self-fracture <![CDATA[σ g-w >σ]]> 5 4 9.1 Self-fracture <![CDATA[σ g-w >σ]]> 6 4 10.4 Self-fracture <![CDATA[σ g-w >σ]]> 7 4 7.5 Self-fracture <![CDATA[σ g-w >σ]]> 8 4 8.3 Self-fracture <![CDATA[σ g-w >σ]]> 9 4 9.7 Self-fracture <![CDATA[σ g-w >σ]]> 10 4 7.1 Self-fracture <![CDATA[σ g-w >σ]]> 11 4 7.5 Self-fracture <![CDATA[σ g-w >σ]]> 12 4 8.4 Self-fracture <![CDATA[σ g-w >σ]]> 13 4 5.6 Fracture along the seam <![CDATA[σ g-w <σ]]> 14 4 6.3 Fracture along the seam <![CDATA[σ g-w <σ]]> 15 4 6.8 Fracture along the seam <![CDATA[σ g-w <σ]]>

[0077] It can be seen from Table 2 that in most examples, the temporary plugging agent fractured on its own fracture surface, and the tensile strength was above 7 N, indicating that the adhesion strength between the temporary plugging agent and the fracture surface was greater than the tensile strength at this time. And as the proportion of the comb-shaped polymer in the temporary plugging agent decreased, the tensile strength of the temporary plugging agent showed a downward trend. Reducing the proportion of 2-(6-isocyanatohexylamide)-6-methyl-4-[h]-pyrimidinone in the comb-shaped polymer seriously affected the adhesion performance of the polymer, and even fracture along the fracture occurred, and the adhesion strength between the temporary plugging agent and the fracture surface was less than the tensile strength.

[0078] The plugging and unplugging performance of the water-soluble temporary plugging agent was evaluated indoors using different batches of artificial cores, and the concentration of the temporary plugging agent was 10 g / L. The water-phase permeability of the fractured core before plugging was K0 Then, the temporary plugging agent was injected into the core fractures. After heating to 60 °C and aging for 30 min, the aqueous permeability K of the core after plugging was then measured. 1 And the core permeability K after the formation water scouring was measured. 2 The temporary plugging rate (F, %) and the plugging removal rate (δ, %) of the temporary plugging agent were calculated by formulas (1) and (2).

[0079]

[0080]

[0081] Table 3 Temporary plugging and plugging removal performances of the temporary plugging agent

[0082]

[0083]

[0084] As can be seen from Table 3, the temporary plugging rates of Examples 1, 2, 4, and 7 were all above 90%. After the formation water scouring, the core permeability recovered, and the plugging removal rates all reached above 94%. Moreover, as the core permeability gradually increased, the temporary plugging rate gradually decreased, and the recovery rate gradually increased. This shows that the temporary plugging agent has good selective temporary plugging and plugging removal performances.

[0085] From the data of Example 2 with different batches of artificial cores, it can be seen that as the core permeability gradually increases, the temporary plugging rate gradually decreases, and the recovery rate gradually increases. This shows that the temporary plugging agent has good selective temporary plugging and plugging removal performances.

[0086] The above are only the preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A polymer gel temporary plugging agent, characterized in that, it comprises the following components in weight percentage: 55% - 80% of a comb-shaped structure polymer main agent, 5% - 10% of 500 - 800 mesh ultra-fine calcium carbonate powder, 5% - 10% of 100 - 300 mesh mica powder, 5 - 15% of plant fiber, and 5 - 10% of ceramic fiber.

2. The polymer gel temporary plugging agent according to claim 1, characterized in that: the plant fiber is selected from any one of hemp and wheat straws, cotton fiber, walnut shell or coconut shell.

3. The polymer gel temporary plugging agent according to claim 1 or 2, characterized in that: the comb-shaped structure polymer main agent is polymerized from sodium styrene sulfonate, α-olefin and 2-(6-isocyanatohexylamine amide)-6-methyl-4-[h]-pyrimidinone as monomers.

4. The polymer gel temporary plugging agent according to claim 3, characterized in that: the α-olefin is pentaerythritol allyl ether, and the structural formula of the comb-shaped structure polymer main agent is as follows: the α-olefin is acrylamide, and the structural formula of the comb-shaped structure polymer main agent is as follows:

5. A preparation method of the polymer gel temporary plugging agent according to any one of claims 1 to 4, characterized in that, it comprises the following steps: 1) Prepare a comb-shaped structure polymer main agent; 2) Mix each component according to the amount of the formula to obtain it.

6. The preparation method of the polymer gel temporary plugging agent according to claim 5, characterized in that, in step 1), the preparation method of the comb-shaped structure polymer main agent comprises the following steps: S1: Prepare a sodium styrene sulfonate-α-olefin binary copolymer by carrying out an alkenyl free radical reaction with sodium styrene sulfonate and α-olefin; S2: Carry out a grafting reaction with 2-(6-isocyanatohexylamine amide)-6-methyl-4-[h]-pyrimidinone and the active hydrogen in the side chain of the binary copolymer obtained in step 1) to prepare the comb-shaped structure polymer main agent.

7. The preparation method of the polymer gel temporary plugging agent according to claim 6, characterized in that: the specific steps of step S1 are as follows: Add sodium styrene sulfonate, α-olefin, and catalyst I into a deionized aqueous solution, mix evenly, heat up to 100°C - 140°C, react for 4 - 10 hours, and after the reaction is completed, cool and dry to obtain a sodium styrene sulfonate-α-olefin binary copolymer; the specific steps of step S2 are as follows: Dissolve the sodium styrene sulfonate-α-olefin binary copolymer and 2-(6-isocyanatohexylamine amide)-6-methyl-4-[h]-pyrimidinone in solvent I, add a trace amount of basic catalyst II, mix evenly, react at 20°C - 60°C for 10 - 16 hours, and after the reaction is completed, cool, dry, and pulverize to obtain a comb-shaped structure polymer main agent.

8. The preparation method of the polymer gel temporary plugging agent according to claim 7, characterized in that: The molar ratio of sodium styrene sulfonate, α-olefin, catalyst I, 2-(6-isocyanatohexylaminoformamide)-6-methyl-4H-pyrimidinone, and basic catalyst II is (1 - 1.3):(1 - 1.5):(0.01 - 0.03):(0.2 - 0.5):(0.01 - 0.03); The catalyst I includes an oxidizing agent and a reducing agent added successively, and the molar ratio of the oxidizing agent to the reducing agent is 3:(2 - 3).

9. The preparation method of the polymer gel temporary plugging agent according to claim 8, characterized in that: The oxidizing agent is selected from any one of hydrogen peroxide or persulfate; The reducing agent is selected from any one of bisulfite, sulfite or thiosulfate; The solvent I is selected from any one or more of N,N-dimethylformamide, methanol, ethanol or dimethyl sulfoxide; The basic catalyst is selected from any one or more of sodium hydroxide or potassium hydroxide.

10. An application of the polymer gel temporary plugging agent according to any one of claims 1 to 4, characterized in that: It is used as a temporary plugging agent for oil and gas development.

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