High-strength concrete pole and preparation method thereof

Abstract

The invention relates to the technical field of building materials, and discloses a high-strength concrete pole and a preparation method thereof. A semi-continuous seed emulsion polymerization method is adopted, a modified monomer is added to prepare a modified styrene-acrylic emulsion, pretreated recycled aggregate prepared from waste concrete and graphene oxide are added into the modified styrene-acrylic emulsion to obtain recycled aggregate, the recycled aggregate, cement, quartz sand, a polycarboxylic acid water reducer and water are mixed to prepare cement pole slurry, and the cement pole slurry is prepared into the concrete pole. And finally, the high-strength cement pole is prepared from the cement pole slurry and reinforcing steel bars through centrifugal forming and steam curing processes. The cement pole prepared by the invention has good mechanical properties.

Description

Technical Field

[0001] This invention relates to the field of building materials technology, specifically to a high-strength cement pole and its preparation method. Background Technology

[0002] As a key load-bearing component in infrastructure construction such as power, communications, and railways, the mechanical properties of cement poles directly affect the safety and durability of line erection. Currently, the industry generally uses reinforced concrete structures, manufactured through centrifugal molding and steam curing processes. In practical applications, most manufacturers add a small amount of recycled aggregate to cement poles to replace natural aggregate, thereby reducing production costs. However, recycled aggregate has disadvantages such as low strength, low bulk density, high porosity, high water absorption, and high crushing index, resulting in significantly lower performance than natural aggregate and consequently leading to the degradation of the mechanical properties of cement poles. Summary of the Invention

[0003] (a) Technical problems to be solved

[0004] To address the shortcomings of existing technologies, this invention provides a high-strength cement pole and its preparation method. The cement pole prepared by this invention exhibits excellent mechanical properties.

[0005] (II) Technical Solution

[0006] To achieve the above objectives, the present invention provides the following technical solution: a high-strength cement pole, comprising the following weight components: 150-180 parts by weight of waste concrete, 30-40 parts by weight of modified styrene-acrylic emulsion, 4-7 parts by weight of graphene oxide, 300-360 parts by weight of cement, 75-95 parts by weight of quartz sand, 3-6 parts by weight of polycarboxylate superplasticizer, 170-200 parts by weight of water, and 12-18 parts by weight of steel reinforcement.

[0007] Preferably, the method for preparing the modified styrene-acrylic emulsion includes the following steps:

[0008] (1) Under a nitrogen atmosphere, add 2.5-4.2g of sodium bisulfite to 30-60mL of deionized water solvent and stir to dissolve. Dissolve 3.4-5.7g of 2-(naphthyl-2-yl)ethylene oxide in 20-40mL of acetone solvent and add it dropwise to the sodium bisulfite solution at 35-45℃. The dropwise addition time is controlled at 1-1.5h. After the dropwise addition is completed, continue the reaction for 2-3h. After the reaction is completed, cool the reaction solution in an ice-water bath. Filter the crystals that precipitate after cooling and recrystallize to obtain intermediate 1.

[0009] (2) Add 2.6-3 mL of acetone and 1.5-2 mL of deionized water to the reactor as solvent. At 0-5℃, add 1.25-1.55 g of cyanuric chloride and stir to dissolve. Dissolve 1.9-2 g of intermediate 1 in 5-10 mL of acetone solvent and add it dropwise to the cyanuric chloride solution along with 2.9-3.1 g of sodium hydroxide solution. After the addition is complete, react for 1.5-3.5 h. Raise the temperature to 42-50℃ and dissolve 1-1.2 g of 1-(pyridin-4-yl)but-3-en-1-amine in 4-8 mL of acetone solvent and add it dropwise to the above reaction solution along with 2.9-3.1 g of sodium hydroxide solution. After the addition is complete, continue to react for 2-4 h. After the reaction is complete, filter, wash and vacuum dry to obtain the modified sulfonic acid functional monomer.

[0010] (3) Under a nitrogen atmosphere, add 1.52-1.6g of N-cyclohexyl monoethanolamine, 0.01-0.03g of potassium carbonate catalyst, and 0.02-0.04g of polymerization inhibitor to 60-80mL of tetrahydrofuran solvent, stir and mix, add 2.8-3.2g of acryloyloxypropyltrimethoxysilane, heat to 30-40℃ and react for 2.5-4.5h. After the reaction is completed, filter, wash and dry to obtain cyclohexylsilane intermediate;

[0011] (4) Add 1.7-1.8g of cyclohexylsilane intermediate and 0.25-0.35g of triethylamine acid-binding agent to 20-50mL of butanone solvent, stir to dissolve, add 0.75-0.85g of 10-undecenoyl chloride dropwise, after the addition is complete, react at 0-10℃ for 1.5-2.5h, then heat to 25-30℃ for 4-7h. After the reaction is complete, filter, remove the solvent by rotary evaporation to obtain the modified hydrophobic functional monomer;

[0012] (5) Add 0.06g of sodium dodecylbenzenesulfonate emulsifier to 15mL of deionized water and stir at 20℃ until emulsified and dispersed. Add 1g of styrene, 2.4g of butyl acrylate, 0.1g of acrylic acid, 0.2g of modified sulfonic acid functional monomer, and 0.3g of modified hydrophobic functional monomer to the mixture and stir to obtain a pre-emulsion. Add 5mL of deionized water and 0.08g of sodium dodecylbenzenesulfonate emulsifier to the reactor and heat to 72℃. Add 5% of the pre-emulsion and 0.01g of ammonium persulfate initiator to the mixture. After reacting for 25min, heat to 84℃ and continue to add the remaining pre-emulsion dropwise over a period of 2h. After the addition is complete, heat to 87℃ and keep warm for 1h. After the warming period, cool down to 30℃ and add 2mL of 9% sodium hydroxide solution to adjust the pH to 7. Filter to obtain the modified styrene-acrylic emulsion.

[0013] Preferably, the mass fraction of the sodium hydroxide solution in step (2) is 9.4%-10.6%.

[0014] Preferably, the polymerization inhibitor in step (3) is hydroquinone.

[0015] Preferably, the emulsifier in step (5) is sodium dodecylbenzenesulfonate.

[0016] Preferably, the initiator in step (5) is ammonium persulfate.

[0017] Preferably, the dripping time of the remaining pre-emulsion in step (5) is controlled at 2-2.5h.

[0018] Preferably, the preparation method of the high-strength cement pole is as follows: waste concrete is crushed, screened, and washed to obtain pretreated recycled aggregate; graphene oxide is added to modified styrene-acrylic emulsion and ultrasonically dispersed for 20-30 minutes; pretreated recycled aggregate is added to it and stirred for 10-15 minutes; it is then dried to obtain recycled aggregate; cement and quartz sand are added to it and stirred for 5-10 minutes; polycarboxylate superplasticizer and water are added and stirred for 15-25 minutes to obtain cement pole slurry; steel bars are cold-drawn, cut, and bent, and then tied into steel cages; the steel cages are placed in steel molds, and cement pole slurry is injected; the mixture is centrifuged and molded using a centrifuge, and steam-cured for 6-8 hours to obtain a high-strength cement pole.

[0019] (iii) Beneficial technical effects

[0020] This invention employs a semi-continuous seed emulsion polymerization method to prepare a modified styrene-acrylic emulsion by adding modified sulfonic acid functional monomers and modified hydrophobic functional monomers. Pretreated recycled aggregates made from waste concrete and graphene oxide are added to the modified styrene-acrylic emulsion to obtain recycled aggregates. The recycled aggregates, cement, quartz sand, polycarboxylate superplasticizer, and water are mixed to obtain a cement pole slurry. Finally, the cement pole slurry and reinforcing steel are centrifuged and steam-cured to produce a high-strength cement pole.

[0021] Modified styrene-acrylic emulsion, as an organic polymer, allows its molecular chains to penetrate the surface and internal pores of recycled aggregates, forming a continuous film. This reduces the internal porosity of concrete, optimizes structural density, reduces aggregate defects, and improves the interfacial transition zone between aggregates and the cement matrix, thereby enhancing the mechanical properties of cement. The sulfonic acid groups in the modified sulfonic acid functional monomers strengthen the calcium ion contact sites on the polymer chain segments, enhancing the chelation effect between the sulfonic acid groups and calcium ions in cement hydration products. This effectively improves the chemical bonding between aggregates and the cement matrix, further enhancing the mechanical properties of cement. The nitrogen atoms in the triazine and pyridine groups form hydrogen bonds with hydroxyl groups on the aggregate surface, further improving the bond strength between aggregates and modified styrene-acrylic emulsion. The silane groups in the modified hydrophobic functional monomers, after hydrolysis, react with hydroxyl groups on the aggregate surface to form stable siloxane bonds. The formation of a hydrophobic film blocks water molecule penetration, thereby improving the mechanical properties of the aggregate. The naphthyl, cyclohexyl, and long-chain alkyl groups on the polymer chain create a steric hindrance effect. This highly hydrophobic and sterically hindered structure can reduce polymer chain entanglement, thereby reducing the viscosity of the emulsion, increasing mechanical stability and cohesive strength, and thus improving the mechanical properties of cement. As a nanomaterial, graphene oxide can seal the pores in concrete through filling, improving its density. Graphene oxide can adsorb cement particles with its large specific surface area and high surface energy. At the same time, it promotes and guides the growth and crystallization of hydration products through nucleation effect, thereby forming "cluster" hydration products, further enhancing the density of concrete. Under the filling and hydration regulation effect of graphene oxide, the internal structure of concrete is dense and the mechanical properties are better. Attached Figure Description

[0022] Figure 1 It is the synthetic reaction formula for modified sulfonic acid functional monomers.

[0023] Figure 2 It is the synthetic reaction formula for modified hydrophobic functional monomers. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention are described clearly and completely. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] To better understand the above technical solutions, the following will provide a detailed description of the technical solutions in conjunction with the accompanying drawings and specific embodiments.

[0026] Example 1

[0027] (1) Under a nitrogen atmosphere, add 2.5 g of sodium bisulfite to 30 mL of deionized water solvent and stir to dissolve. Dissolve 3.4 g of 2-(naphthyl-2-yl)ethylene oxide in 20 mL of acetone solvent and add it dropwise to the sodium bisulfite solution at 35 °C. The dropwise addition time is controlled at 1 h. After the dropwise addition is completed, continue the reaction for 2 h. After the reaction is completed, cool the reaction solution in an ice-water bath. Filter the crystals that precipitate after cooling and recrystallize to obtain intermediate 1.

[0028] (2) Add 2.6 mL of acetone and 1.5 mL of deionized water to the reactor as solvent. At 0 °C, add 1.25 g of cyanuric chloride and stir to dissolve. Dissolve 1.9 g of intermediate 1 in 5 mL of acetone solvent and add it dropwise to the cyanuric chloride solution along with 2.9 g of sodium hydroxide solution with a mass fraction of 9.4%. After the addition is complete, react for 1.5 h. Raise the temperature to 42 °C and dissolve 1 g of 1-(pyridin-4-yl)but-3-en-1-amine in 4 mL of acetone solvent and add it dropwise to the above reaction solution along with 2.9 g of sodium hydroxide solution with a mass fraction of 9.4%. After the addition is complete, continue to react for 2 h. After the reaction is complete, filter, wash and vacuum dry to obtain the modified sulfonic acid functional monomer.

[0029] (3) Under a nitrogen atmosphere, 1.52 g of N-cyclohexyl monoethanolamine, 0.01 g of potassium carbonate catalyst, and 0.02 g of hydroquinone polymerization inhibitor were added to 60 mL of tetrahydrofuran solvent. The mixture was stirred and mixed. 2.8 g of acryloyloxypropyltrimethoxysilane was added to the mixture. The temperature was raised to 30 °C and the reaction was carried out for 2.5 h. After the reaction was completed, the mixture was filtered, washed and dried to obtain cyclohexylsilane intermediate.

[0030] (4) Add 1.7g of cyclohexylsilane intermediate and 0.25g of triethylamine acid-binding agent to 20mL of butanone solvent, stir to dissolve, add 0.75g of 10-undecenoyl chloride dropwise, after the addition is complete, react at 0℃ for 1.5h, then heat to 25℃ and react for 4h. After the reaction is complete, filter, remove the solvent by rotary evaporation, and obtain the modified hydrophobic functional monomer.

[0031] (5) Add 0.06g of sodium dodecylbenzenesulfonate emulsifier to 15mL of deionized water and stir at 20℃ until emulsified and dispersed. Add 1g of styrene, 2.4g of butyl acrylate, 0.1g of acrylic acid, 0.2g of modified sulfonic acid functional monomer, and 0.3g of modified hydrophobic functional monomer to the mixture and stir to obtain a pre-emulsion. Add 5mL of deionized water and 0.08g of sodium dodecylbenzenesulfonate emulsifier to the reactor and heat to 72℃. Add 5% of the pre-emulsion and 0.01g of ammonium persulfate initiator to the mixture. After reacting for 25min, heat to 84℃ and continue to add the remaining pre-emulsion dropwise. The dropwise addition time is controlled at 2h. After the dropwise addition is completed, heat to 87℃ and keep warm for 1h. After the warming is completed, cool down to 30℃ and add 2mL of sodium hydroxide solution with a mass fraction of 9% to adjust the pH value to 7. Filter to obtain modified styrene-acrylic emulsion.

[0032] (6) 150 parts by weight of waste concrete is crushed, screened and washed to obtain pretreated recycled aggregate. 4 parts by weight of graphene oxide is added to 30 parts by weight of modified styrene-acrylic emulsion and ultrasonically dispersed for 20 min. The pretreated recycled aggregate is added to it and stirred for 10 min. It is then dried to obtain recycled aggregate. 300 parts by weight of cement and 75 parts by weight of quartz sand are added to it and stirred for 5 min. 3 parts by weight of polycarboxylate superplasticizer and 170 parts by weight of water are added and stirred for 15 min to obtain cement pole slurry. 12 parts by weight of steel bars are cold-drawn, cut and bent and tied into steel cages. The steel cages are placed in steel molds and cement pole slurry is injected. The steel bars are centrifuged and molded by centrifuge and steam-cured for 6 h to obtain high-strength cement poles.

[0033] Example 2

[0034] (1) Under a nitrogen atmosphere, 4.2 g of sodium bisulfite was added to 60 mL of deionized water solvent and stirred to dissolve. 5.7 g of 2-(naphthyl-2-yl)ethylene oxide was dissolved in 40 mL of acetone solvent and added dropwise to the sodium bisulfite solution at 45 °C. The dropwise addition time was controlled at 1.5 h. After the dropwise addition was completed, the reaction was continued for 3 h. After the reaction was completed, the reaction solution was cooled in an ice-water bath. The crystals precipitated after cooling were filtered and recrystallized to obtain intermediate 1.

[0035] (2) Add 3 mL of acetone and 2 mL of deionized water to the reactor as solvents. At 5 °C, add 1.55 g of cyanuric chloride and stir to dissolve. Dissolve 2 g of intermediate 1 in 10 mL of acetone solvent and add it dropwise to the cyanuric chloride solution along with 3.1 g of sodium hydroxide solution with a mass fraction of 10.6%. After the addition is complete, react for 3.5 h. Raise the temperature to 50 °C and dissolve 1.2 g of 1-(pyridin-4-yl)but-3-en-1-amine in 8 mL of acetone solvent and add it dropwise to the above reaction solution along with 3.1 g of sodium hydroxide solution with a mass fraction of 10.6%. After the addition is complete, continue to react for 4 h. After the reaction is complete, filter, wash and vacuum dry to obtain the modified sulfonic acid functional monomer.

[0036] (3) Under a nitrogen atmosphere, 1.6 g of N-cyclohexyl monoethanolamine, 0.03 g of potassium carbonate catalyst, and 0.04 g of hydroquinone polymerization inhibitor were added to 80 mL of tetrahydrofuran solvent. The mixture was stirred and mixed. Then, 3.2 g of acryloyloxypropyltrimethoxysilane was added. The mixture was heated to 40 °C and reacted for 4.5 h. After the reaction was completed, the mixture was filtered, washed and dried to obtain cyclohexylsilane intermediate.

[0037] (4) Add 1.8g of cyclohexylsilane intermediate and 0.35g of triethylamine acid-binding agent to 50mL of butanone solvent, stir to dissolve, add 0.85g of 10-undecenoyl chloride dropwise, after the addition is complete, react at 10℃ for 2.5h, then heat to 30℃ and react for 7h. After the reaction is complete, filter, remove the solvent by rotary evaporation to obtain the modified hydrophobic functional monomer.

[0038] (5) Add 0.08 g of sodium dodecylbenzenesulfonate emulsifier to 20 mL of deionized water and stir at 30 °C until emulsified and dispersed. Add 1.4 g of styrene, 2.8 g of butyl acrylate, 0.3 g of acrylic acid, 0.5 g of modified sulfonic acid functional monomer, and 0.4 g of modified hydrophobic functional monomer to the mixture and stir to obtain a pre-emulsion. Add 10 mL of deionized water and 0.1 g of sodium dodecylbenzenesulfonate to the reactor for emulsification. The agent was heated to 78°C, and 10% of the pre-emulsion and 0.03g of ammonium persulfate initiator were added. After reacting for 45 minutes, the temperature was raised to 86°C, and the remaining pre-emulsion was added dropwise over a period of 2.5 hours. After the addition was complete, the temperature was raised to 89°C and kept at that temperature for 1.5 hours. After the holding time was completed, the temperature was lowered to 38°C, and 5mL of 11% sodium hydroxide solution was added to adjust the pH to 9. The mixture was then filtered to obtain the modified styrene-acrylic emulsion.

[0039] (6) 180 parts by weight of waste concrete is crushed, screened and washed to obtain pretreated recycled aggregate. 7 parts by weight of graphene oxide is added to 40 parts by weight of modified styrene-acrylic emulsion and ultrasonically dispersed for 30 min. The pretreated recycled aggregate is added to it and stirred for 15 min. It is then dried to obtain recycled aggregate. 360 parts by weight of cement and 95 parts by weight of quartz sand are added to it and stirred for 10 min. 6 parts by weight of polycarboxylate superplasticizer and 200 parts by weight of water are added and stirred for 25 min to obtain cement pole slurry. 18 parts by weight of steel bars are cold-drawn, cut and bent and tied into steel cages. The steel cages are placed in steel molds and cement pole slurry is injected. The steel bars are centrifuged and molded by centrifuge and steam-cured for 8 h to obtain high-strength cement poles.

[0040] Example 3

[0041] (1) Under a nitrogen atmosphere, 3.35 g of sodium bisulfite was added to 45 mL of deionized water solvent and stirred to dissolve. 4.55 g of 2-(naphthyl-2-yl)ethylene oxide was dissolved in 30 mL of acetone solvent and added dropwise to the sodium bisulfite solution at 40 °C. The dropwise addition time was controlled at 1.2 h. After the dropwise addition was completed, the reaction was continued for 2.5 h. After the reaction was completed, the reaction solution was cooled in an ice-water bath. The crystals precipitated after cooling were filtered and recrystallized to obtain intermediate 1.

[0042] (2) Add 2.8 mL of acetone and 1.8 mL of deionized water to the reactor as solvent. At 2 °C, add 1.4 g of cyanuric chloride and stir to dissolve. Dissolve 1.95 g of intermediate 1 in 8 mL of acetone solvent and add it dropwise to the cyanuric chloride solution along with 3 g of sodium hydroxide solution with a mass fraction of 10%. After the addition is complete, react for 2.5 h. Raise the temperature to 46 °C and dissolve 1.1 g of 1-(pyridin-4-yl)but-3-en-1-amine in 6 mL of acetone solvent and add it dropwise to the above reaction solution along with 3 g of sodium hydroxide solution with a mass fraction of 10%. After the addition is complete, continue to react for 3 h. After the reaction is complete, filter, wash and vacuum dry to obtain the modified sulfonic acid functional monomer.

[0043] (3) Under a nitrogen atmosphere, 1.56 g of N-cyclohexyl monoethanolamine, 0.02 g of potassium carbonate catalyst, and 0.03 g of hydroquinone polymerization inhibitor were added to 70 mL of tetrahydrofuran solvent. The mixture was stirred and mixed. Then, 3 g of acryloyloxypropyltrimethoxysilane was added. The mixture was heated to 35 °C and reacted for 3.5 h. After the reaction was completed, the mixture was filtered, washed and dried to obtain cyclohexylsilane intermediate.

[0044] (4) Add 1.75 g of cyclohexylsilane intermediate and 0.3 g of triethylamine acid-binding agent to 35 mL of butanone solvent, stir to dissolve, add 0.8 g of 10-undecenoyl chloride dropwise, after the addition is complete, react at 5 °C for 2 h, then raise the temperature to 28 °C and react for 5.5 h. After the reaction is complete, filter, remove the solvent by rotary evaporation, and obtain the modified hydrophobic functional monomer.

[0045] (5) Add 0.07 g of sodium dodecylbenzenesulfonate emulsifier to 18 mL of deionized water and stir at 25 °C until emulsified and dispersed. Add 1.2 g of styrene, 2.6 g of butyl acrylate, 0.2 g of acrylic acid, 0.35 g of modified sulfonic acid functional monomer, and 0.35 g of modified hydrophobic functional monomer to the mixture and stir to obtain a pre-emulsion. Add 8 mL of deionized water and 0.09 g of sodium dodecylbenzenesulfonate emulsifier to the reactor. The temperature was raised to 75℃, and 7.5% pre-emulsion and 0.02g ammonium persulfate initiator were added. After reacting for 35 minutes, the temperature was raised to 85℃, and the remaining pre-emulsion was added dropwise over a period of 2.2 hours. After the addition was complete, the temperature was raised to 88℃ and kept at that temperature for 1.2 hours. After the holding time was completed, the temperature was lowered to 34℃, and 3.5mL of 10% sodium hydroxide solution was added to adjust the pH to 8. The mixture was then filtered to obtain the modified styrene-acrylic emulsion.

[0046] (6) 165 parts by weight of waste concrete is crushed, screened and washed to obtain pretreated recycled aggregate. 5.5 parts by weight of graphene oxide is added to 35 parts by weight of modified styrene-acrylic emulsion and ultrasonically dispersed for 25 min. The pretreated recycled aggregate is added to it and stirred for 12 min. It is then dried to obtain recycled aggregate. 330 parts by weight of cement and 85 parts by weight of quartz sand are added to it and stirred for 8 min. 4.5 parts by weight of polycarboxylate superplasticizer and 185 parts by weight of water are added and stirred for 20 min to obtain cement pole slurry. 15 parts by weight of steel bars are cold-drawn, cut and bent and tied into steel cages. The steel cages are placed in steel molds and cement pole slurry is injected. The steel bars are centrifuged and molded by centrifuge and steam-cured for 7 h to obtain high-strength cement poles.

[0047] Example 4

[0048] (1) Under a nitrogen atmosphere, add 2.5 g of sodium bisulfite to 30 mL of deionized water solvent and stir to dissolve. Dissolve 3.4 g of 2-(naphthyl-2-yl)ethylene oxide in 20 mL of acetone solvent and add it dropwise to the sodium bisulfite solution at 35 °C. The dropwise addition time is controlled at 1 h. After the dropwise addition is completed, continue the reaction for 2 h. After the reaction is completed, cool the reaction solution in an ice-water bath. Filter the crystals that precipitate after cooling and recrystallize to obtain intermediate 1.

[0049] (2) Add 2.6 mL of acetone and 1.5 mL of deionized water to the reactor as solvent. At 0 °C, add 1.25 g of cyanuric chloride and stir to dissolve. Dissolve 1.9 g of intermediate 1 in 5 mL of acetone solvent and add it dropwise to the cyanuric chloride solution along with 2.9 g of sodium hydroxide solution with a mass fraction of 9.4%. After the addition is complete, react for 1.5 h. Raise the temperature to 42 °C and dissolve 1 g of 1-(pyridin-4-yl)but-3-en-1-amine in 4 mL of acetone solvent and add it dropwise to the above reaction solution along with 2.9 g of sodium hydroxide solution with a mass fraction of 9.4%. After the addition is complete, continue to react for 2 h. After the reaction is complete, filter, wash and vacuum dry to obtain the modified sulfonic acid functional monomer.

[0050] (3) Under a nitrogen atmosphere, 1.6 g of N-cyclohexyl monoethanolamine, 0.03 g of potassium carbonate catalyst, and 0.04 g of hydroquinone polymerization inhibitor were added to 80 mL of tetrahydrofuran solvent. The mixture was stirred and mixed. Then, 3.2 g of acryloyloxypropyltrimethoxysilane was added. The mixture was heated to 40 °C and reacted for 4.5 h. After the reaction was completed, the mixture was filtered, washed and dried to obtain cyclohexylsilane intermediate.

[0051] (4) Add 1.8g of cyclohexylsilane intermediate and 0.35g of triethylamine acid-binding agent to 50mL of butanone solvent, stir to dissolve, add 0.85g of 10-undecenoyl chloride dropwise, after the addition is complete, react at 10℃ for 2.5h, then heat to 30℃ and react for 7h. After the reaction is complete, filter, remove the solvent by rotary evaporation to obtain the modified hydrophobic functional monomer.

[0052] (5) Add 0.07 g of sodium dodecylbenzenesulfonate emulsifier to 18 mL of deionized water and stir at 25 °C until emulsified and dispersed. Add 1.2 g of styrene, 2.6 g of butyl acrylate, 0.2 g of acrylic acid, 0.35 g of modified sulfonic acid functional monomer, and 0.35 g of modified hydrophobic functional monomer to the mixture and stir to obtain a pre-emulsion. Add 8 mL of deionized water and 0.09 g of sodium dodecylbenzenesulfonate emulsifier to the reactor. The temperature was raised to 75℃, and 7.5% pre-emulsion and 0.02g ammonium persulfate initiator were added. After reacting for 35 minutes, the temperature was raised to 85℃, and the remaining pre-emulsion was added dropwise over a period of 2.2 hours. After the addition was complete, the temperature was raised to 88℃ and kept at that temperature for 1.2 hours. After the holding time was completed, the temperature was lowered to 34℃, and 3.5mL of 10% sodium hydroxide solution was added to adjust the pH to 8. The mixture was then filtered to obtain the modified styrene-acrylic emulsion.

[0053] (6) 165 parts by weight of waste concrete is crushed, screened and washed to obtain pretreated recycled aggregate. 5.5 parts by weight of graphene oxide is added to 35 parts by weight of modified styrene-acrylic emulsion and ultrasonically dispersed for 25 min. The pretreated recycled aggregate is added to it and stirred for 12 min. It is then dried to obtain recycled aggregate. 330 parts by weight of cement and 85 parts by weight of quartz sand are added to it and stirred for 8 min. 4.5 parts by weight of polycarboxylate superplasticizer and 185 parts by weight of water are added and stirred for 20 min to obtain cement pole slurry. 15 parts by weight of steel bars are cold-drawn, cut and bent and tied into steel cages. The steel cages are placed in steel molds and cement pole slurry is injected. The steel bars are centrifuged and molded by centrifuge and steam-cured for 7 h to obtain high-strength cement poles.

[0054] Example 5

[0055] (1) Under a nitrogen atmosphere, 3.35 g of sodium bisulfite was added to 45 mL of deionized water solvent and stirred to dissolve. 4.55 g of 2-(naphthyl-2-yl)ethylene oxide was dissolved in 30 mL of acetone solvent and added dropwise to the sodium bisulfite solution at 40 °C. The dropwise addition time was controlled at 1.2 h. After the dropwise addition was completed, the reaction was continued for 2.5 h. After the reaction was completed, the reaction solution was cooled in an ice-water bath. The crystals precipitated after cooling were filtered and recrystallized to obtain intermediate 1.

[0056] (2) Add 2.8 mL of acetone and 1.8 mL of deionized water to the reactor as solvent. At 2 °C, add 1.4 g of cyanuric chloride and stir to dissolve. Dissolve 1.95 g of intermediate 1 in 8 mL of acetone solvent and add it dropwise to the cyanuric chloride solution along with 3 g of sodium hydroxide solution with a mass fraction of 10%. After the addition is complete, react for 2.5 h. Raise the temperature to 46 °C and dissolve 1.1 g of 1-(pyridin-4-yl)but-3-en-1-amine in 6 mL of acetone solvent and add it dropwise to the above reaction solution along with 3 g of sodium hydroxide solution with a mass fraction of 10%. After the addition is complete, continue to react for 3 h. After the reaction is complete, filter, wash and vacuum dry to obtain the modified sulfonic acid functional monomer.

[0057] (3) Under a nitrogen atmosphere, 1.52 g of N-cyclohexyl monoethanolamine, 0.01 g of potassium carbonate catalyst, and 0.02 g of hydroquinone polymerization inhibitor were added to 60 mL of tetrahydrofuran solvent. The mixture was stirred and mixed. 2.8 g of acryloyloxypropyltrimethoxysilane was added to the mixture. The temperature was raised to 30 °C and the reaction was carried out for 2.5 h. After the reaction was completed, the mixture was filtered, washed and dried to obtain cyclohexylsilane intermediate.

[0058] (4) Add 1.7g of cyclohexylsilane intermediate and 0.25g of triethylamine acid-binding agent to 20mL of butanone solvent, stir to dissolve, add 0.75g of 10-undecenoyl chloride dropwise, after the addition is complete, react at 0℃ for 1.5h, then heat to 25℃ and react for 4h. After the reaction is complete, filter, remove the solvent by rotary evaporation, and obtain the modified hydrophobic functional monomer.

[0059] (5) Add 0.08 g of sodium dodecylbenzenesulfonate emulsifier to 20 mL of deionized water and stir at 30 °C until emulsified and dispersed. Add 1.4 g of styrene, 2.8 g of butyl acrylate, 0.3 g of acrylic acid, 0.5 g of modified sulfonic acid functional monomer, and 0.4 g of modified hydrophobic functional monomer to the mixture and stir to obtain a pre-emulsion. Add 10 mL of deionized water and 0.1 g of sodium dodecylbenzenesulfonate to the reactor for emulsification. The agent was heated to 78°C, and 10% of the pre-emulsion and 0.03g of ammonium persulfate initiator were added. After reacting for 45 minutes, the temperature was raised to 86°C, and the remaining pre-emulsion was added dropwise over a period of 2.5 hours. After the addition was complete, the temperature was raised to 89°C and kept at that temperature for 1.5 hours. After the holding time was completed, the temperature was lowered to 38°C, and 5mL of 11% sodium hydroxide solution was added to adjust the pH to 9. The mixture was then filtered to obtain the modified styrene-acrylic emulsion.

[0060] (6) 180 parts by weight of waste concrete is crushed, screened and washed to obtain pretreated recycled aggregate. 7 parts by weight of graphene oxide is added to 40 parts by weight of modified styrene-acrylic emulsion and ultrasonically dispersed for 30 min. The pretreated recycled aggregate is added to it and stirred for 15 min. It is then dried to obtain recycled aggregate. 360 parts by weight of cement and 95 parts by weight of quartz sand are added to it and stirred for 10 min. 6 parts by weight of polycarboxylate superplasticizer and 200 parts by weight of water are added and stirred for 25 min to obtain cement pole slurry. 18 parts by weight of steel bars are cold-drawn, cut and bent and tied into steel cages. The steel cages are placed in steel molds and cement pole slurry is injected. The steel bars are centrifuged and molded by centrifuge and steam-cured for 8 h to obtain high-strength cement poles.

[0061] Comparative Example 1

[0062] The difference between this comparative example and Example 5 is that step (5) does not contain the modified sulfonic acid functional monomer.

[0063] Comparative Example 2

[0064] The difference between this comparative example and Example 5 is that step (5) does not contain the modified hydrophobic functional monomer.

[0065] Comparative Example 3

[0066] The difference between this comparative example and Example 5 is that step (6) does not contain graphene oxide.

[0067] Referring to GB / T4623-2014 "Circular Concrete Poles", the simple-supported test method was used to determine the compressive strength, flexural strength, and crack resistance coefficient of the cement poles in Examples 1-5 and Comparative Examples 1-3. A load-bearing capacity test moment was applied for 3 minutes, the load was removed, and the poles were cured at room temperature for 28 days before their compressive strength and flexural strength were determined. The test results are shown in Table 1.

[0068] Table 1: Mechanical property tests.

[0069] project Compressive strength (MPa) Flexural strength (MPa) Crack resistance coefficient 28-day compressive strength (MPa) 28-day flexural strength (MPa) Example 1 213.9 64.9 2.2 155.6 59.7 Example 2 214.6 65.3 2.1 157.2 60.2 Example 3 215.5 66.1 2.1 158.4 62.0 Example 4 214.9 65.7 2.2 156.7 61.5 Example 5 216.0 65.8 2.2 159.5 62.8 Comparative Example 1 202.4 50.6 1.9 137.6 41.2 Comparative Example 2 197.5 46.3 1.9 132.6 35.9 Comparative Example 3 190.6 43.8 1.7 124.8 33.7

[0070] As shown in Table 1, the cement poles in Examples 1-5 of the present invention have better mechanical properties than the cement poles in Comparative Examples 1-3.

[0071] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0072] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

[0073] Those skilled in the art should understand that the above descriptions are merely several specific embodiments of the present invention, and not all embodiments. It should be noted that many modifications and improvements can be made by those skilled in the art, and all modifications or improvements not exceeding the scope of the claims should be considered within the protection scope of the present invention.

Claims

1. A high-strength cement pole, characterized in that, It includes the following components by weight: 150-180 parts by weight of waste concrete, 30-40 parts by weight of modified styrene-acrylic emulsion, 4-7 parts by weight of graphene oxide, 300-360 parts by weight of cement, 75-95 parts by weight of quartz sand, 3-6 parts by weight of polycarboxylate superplasticizer, 170-200 parts by weight of water, and 12-18 parts by weight of steel reinforcement.

2. The high-strength cement pole according to claim 1, characterized in that, The method for preparing the modified styrene-acrylic emulsion includes the following steps: (1) Under a nitrogen atmosphere, add 2.5-4.2g of sodium bisulfite to 30-60mL of deionized water solvent and stir to dissolve. Dissolve 3.4-5.7g of 2-(naphthyl-2-yl)ethylene oxide in 20-40mL of acetone solvent and add it dropwise to the sodium bisulfite solution at 35-45℃. The dropwise addition time is controlled at 1-1.5h. After the dropwise addition is completed, continue the reaction for 2-3h. After the reaction is completed, cool the reaction solution in an ice-water bath. Filter the crystals that precipitate after cooling and recrystallize to obtain intermediate 1. (2) Add 2.6-3 mL of acetone and 1.5-2 mL of deionized water to the reactor as solvent. At 0-5℃, add 1.25-1.55 g of cyanuric chloride and stir to dissolve. Dissolve 1.9-2 g of intermediate 1 in 5-10 mL of acetone solvent and add it dropwise to the cyanuric chloride solution along with 2.9-3.1 g of sodium hydroxide solution. After the addition is complete, react for 1.5-3.5 h. Raise the temperature to 42-50℃ and dissolve 1-1.2 g of 1-(pyridin-4-yl)but-3-en-1-amine in 4-8 mL of acetone solvent and add it dropwise to the above reaction solution along with 2.9-3.1 g of sodium hydroxide solution. After the addition is complete, continue to react for 2-4 h. After the reaction is complete, filter, wash and vacuum dry to obtain the modified sulfonic acid functional monomer. (3) Under a nitrogen atmosphere, add 1.52-1.6g of N-cyclohexyl monoethanolamine, 0.01-0.03g of potassium carbonate catalyst, and 0.02-0.04g of polymerization inhibitor to 60-80mL of tetrahydrofuran solvent, stir and mix, add 2.8-3.2g of acryloyloxypropyltrimethoxysilane, heat to 30-40℃ and react for 2.5-4.5h. After the reaction is completed, filter, wash and dry to obtain cyclohexylsilane intermediate; (4) Add 1.7-1.8g of cyclohexylsilane intermediate and 0.25-0.35g of triethylamine acid-binding agent to 20-50mL of butanone solvent, stir to dissolve, add 0.75-0.85g of 10-undecenoyl chloride dropwise, after the addition is complete, react at 0-10℃ for 1.5-2.5h, then heat to 25-30℃ for 4-7h. After the reaction is complete, filter, remove the solvent by rotary evaporation to obtain the modified hydrophobic functional monomer; (5) Add 0.06g of sodium dodecylbenzenesulfonate emulsifier to 15mL of deionized water and stir at 20℃ until emulsified and dispersed. Add 1g of styrene, 2.4g of butyl acrylate, 0.1g of acrylic acid, 0.2g of modified sulfonic acid functional monomer, and 0.3g of modified hydrophobic functional monomer to the mixture and stir to obtain a pre-emulsion. Add 5mL of deionized water and 0.08g of sodium dodecylbenzenesulfonate emulsifier to the reactor and heat to 72℃. Add 5% of the pre-emulsion and 0.01g of ammonium persulfate initiator to the mixture. After reacting for 25min, heat to 84℃ and continue to add the remaining pre-emulsion dropwise over a period of 2h. After the addition is complete, heat to 87℃ and keep warm for 1h. After the warming period, cool down to 30℃ and add 2mL of 9% sodium hydroxide solution to adjust the pH to 7. Filter to obtain the modified styrene-acrylic emulsion.

3. The high-strength cement pole according to claim 2, characterized in that, In step (2), the mass fraction of the sodium hydroxide solution is 9.4%-10.6%.

4. The high-strength cement pole according to claim 2, characterized in that, The polymerization inhibitor in step (3) is hydroquinone.

5. The high-strength cement pole according to claim 2, characterized in that, The emulsifier in step (5) is sodium dodecylbenzenesulfonate.

6. The high-strength cement pole according to claim 2, characterized in that, The initiator in step (5) is ammonium persulfate.

7. The high-strength cement pole according to claim 2, characterized in that, The dripping time of the remaining pre-emulsion in step (5) is controlled at 2-2.5h.

8. A method for preparing a high-strength cement pole as described in any one of claims 1-7, characterized in that, The preparation method of the high-strength cement pole is as follows: waste concrete is crushed, screened, and washed to obtain pretreated recycled aggregate. Graphene oxide is added to modified styrene-acrylic emulsion and ultrasonically dispersed for 20-30 minutes. The pretreated recycled aggregate is added to the emulsion and stirred for 10-15 minutes. The mixture is then dried to obtain recycled aggregate. Cement and quartz sand are added to the emulsion and stirred for 5-10 minutes. Polycarboxylate superplasticizer and water are added and stirred for another 15-25 minutes to obtain cement pole slurry. Reinforcing bars are cold-drawn, cut, and bent, and then tied into reinforcing cages. The reinforcing cages are placed in steel molds, and then cement pole slurry is injected. The mixture is then centrifuged and molded using a centrifuge and steam-cured for 6-8 hours to obtain a high-strength cement pole.

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