Self-leveling high-strength cement adhesive for porcelain insulators and preparation method thereof

Abstract

The application belongs to the technical field of electric power high voltage, and discloses a self-leveling high-strength cement adhesive for porcelain insulator and a preparation method thereof; the cement adhesive comprises a base material, an additive and water; the additive is 0.1wt%-1.4wt% of the base material; the water is 16wt%-25wt% of the base material; the base material is prepared from the following components in percentage by mass: 40wt%-60wt% of Portland cement, 30wt%-60wt% of porcelain sand and 3wt%-10wt% of silicon powder; the additive comprises polycarboxylic acid compound water reducing agent, anti-cracking agent, defoaming agent and polyether modified organic silicon; the cement adhesive prepared by the application has a strength of more than or equal to 100MPa, and has the characteristics of self-leveling, high mechanical property, moderate elastic modulus, short forming time and good application prospect when being installed in porcelain and steam curing at 40-50℃ for 4-8h.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of electric power high voltage technology, and in particular to a self-leveling high-strength cement adhesive for porcelain insulators and a preparation method thereof. BACKGROUND

[0002] Porcelain insulators are mainly used for the external insulation of high-voltage power transmission and supply lines, ultra-high-voltage power transmission and supply lines, and power station electrical equipment, and therefore must have high external insulation performance. The main components of porcelain insulators are porcelain pieces, cement adhesives, and fittings. The cement adhesive is extremely important as the main material connecting the porcelain pieces and the fittings, and the cement adhesives of most enterprises are currently filled by hand and then vibrated to be compacted, which is low in efficiency.

[0003] However, with the increasing requirements for the performance and quality of products, automated adhesive production has become a necessary trend, and the cement adhesive must be self-leveling without vibration, so how to achieve high strength of the cement adhesive while achieving long-term self-leveling performance has become a key technology.

[0004] To solve the above technical problems, the prior art CN201310703097.8 discloses a cement adhesive, and the strength of the cement adhesive can reach 100 MPa only after 24 hours of molding, 3 days of curing in water at 35-45℃, which is low in efficiency and long in turnover time. The prior art CN202210822440.X uses modified graphene to improve and enhance the performance of the adhesive, but the process of modified graphene is complex, and the amount of modified graphene is large (20-30% of Portland cement), which greatly increases the preparation cost and hinders large-scale industrial application. In addition, the compressive strength of the adhesive can reach 100 MPa only after 2 days of natural curing. The current curing process cycle is long, which greatly increases the inventory pressure and affects the overall production efficiency of porcelain insulators. It is also a technical difficulty and key technology for the entire industry to achieve self-leveling, high strength, and rapid curing and molding. Therefore, improvements need to be made to meet the production and market demand.

[0005] Therefore, the present application provides a self-leveling high-strength cement adhesive for porcelain insulators and a preparation method thereof. SUMMARY

[0006] In order to solve the above-mentioned deficiencies in the prior art, the application provides a self-leveling high-strength cement adhesive for porcelain insulators and a preparation method thereof. The application uses artificial porcelain sand to replace the traditional aggregate with silicon dioxide as the main component, which can not only improve the strength of the cement adhesive, but also greatly reduce the potential risks caused by the alkali-aggregate reaction of traditional river sand. The spherical silicon powder combined with the self-made leveling agent can not only realize the self-leveling of the adhesive and reduce manual operation, but also greatly improve the workability of the cement adhesive with less loss of fluidity. Moreover, the application adopts a steam curing system, which can greatly reduce the production cycle of the cement adhesive, reduce the inventory pressure, greatly reduce the production cost, realize the dual goals of quality improvement and cost reduction, and thus greatly improve and expand the application and market competitiveness of the cement adhesive.

[0007] The self-leveling high-strength cement adhesive for porcelain insulators and the preparation method thereof are achieved by the following technical solutions.

[0008] The first object of the application is to provide a self-leveling high-strength cement adhesive for porcelain insulators, which comprises a base material, an additive, and water. The amount of the additive is 0.1wt% to 1.4wt% of the base material. The amount of the water is 16wt% to 25wt% of the base material.

[0009] The preparation raw materials of the base material include the following components in terms of mass percentage:

[0010] The silicate cement is 40wt% to 60wt%, the porcelain sand is 30wt% to 60wt%, and the silicon powder is 3wt% to 10wt%. The total amount of each preparation raw material of the base material is 100wt%.

[0011] The additive includes a polycarboxylic acid compound water reducing agent, a crack resistance agent, a defoaming agent, and a leveling agent. The leveling agent is a polyether modified organosilicon.

[0012] Further, the amount of the polycarboxylic acid compound water reducing agent is 0.1wt% to 0.3wt% of the base material.

[0013] The amount of the crack resistance agent is 0.1wt% to 0.3wt% of the base material.

[0014] The amount of the defoaming agent is 0.1wt% to 0.3wt% of the base material.

[0015] The amount of the leveling agent is 0.1wt% to 0.5wt% of the base material.

[0016] Further, the polyether modified organosilicon is prepared by the following steps:

[0017] S1, mixing polymethylhydrosiloxane and polyether F-6 to obtain mixture A;

[0018] The mass ratio of the polymethylhydrosiloxane and the polyether F-6 is 1:1.8-2.2.

[0019] S2, uniformly dispersing a catalyst in the mixture A to obtain mixture B;

[0020] S3, performing reflux heating treatment on the mixture B, when the temperature rises to 78-82℃, nitrogen is introduced, then toluene is added, and then the temperature is continuously raised to 105-115℃ for constant temperature reaction for 6-10h, after the reaction is completed, the toluene is removed, and the polyether modified silicone is obtained.

[0021] Further, the catalyst is chloroplatinic acid isopropanol solution; the mass concentration of chloroplatinic acid in the isopropanol solution is 1wt%;

[0022] And the mass ratio of the catalyst to the mixture A is 1.0wt%-2.0wt%:1.

[0023] Further, the mass ratio to the mixture B is 0.15-0.25:1.

[0024] Further, the Portland cement is 525# P I type or P II type cement.

[0025] Further, the porcelain sand is porcelain sand with aluminum content ≥80%, and the particle size is 30-70 mesh.

[0026] Further, the purity of the silicon powder is ≥99%, the silicon powder is spherical and the particle size is 10-200nm.

[0027] Further, the polycarboxylic acid compound water reducing agent is prepared by the following steps:

[0028] Mixing lithium salt into polycarboxylic acid water reducing agent to obtain the polycarboxylic acid compound water reducing agent;

[0029] Wherein, the lithium salt is lithium nitrate or lithium carbonate; and the amount of lithium salt added is 15wt%-25wt% of the polycarboxylic acid water reducing agent.

[0030] Further, the anti-cracking agent is polypropylene fiber, and the length of the polypropylene fiber is 5.5-6.56mm, and the aspect ratio is 5-10.

[0031] Further, the defoaming agent is a hydrocarbon compound with a purity of ≥98%.

[0032] Further, the leveling agent is polyether modified silicone.

[0033] The second object of the present application is to provide a preparation method of the self-leveling high-strength cement adhesive, characterized in that the method comprises the following steps:

[0034] Step 1, the base material, the additive and water are weighed according to the above-mentioned proportion, and are prepared for use; wherein, the base material is prepared according to the following mass percentage ratio, and each preparation raw material is weighed according to the corresponding mass:

[0035] 40wt%-60wt% of Portland cement, 30wt%-60wt% of porcelain sand and 3wt%-10wt% of silica powder;

[0036] Step 2, the Portland cement, the porcelain sand and the silica powder are uniformly mixed to obtain the base material;

[0037] Step 3, the base material and the additive are uniformly mixed, water is added and stirred uniformly to obtain the self-leveling high-strength cement adhesive for porcelain insulator.

[0038] Compared with the prior art, the present application has the following beneficial effects:

[0039] The present application uses Portland cement, porcelain sand and silica powder as the base material of the cement adhesive, mixes them with polycarboxylic acid complexing water reducing agent, anti-cracking agent, defoaming agent, leveling agent and water to form the cement adhesive. The cement adhesive for porcelain insulator prepared by the present application has high compressive strength, high flexural strength and fast molding time, which can greatly improve the site turnover period of the product, greatly improve the production efficiency, and the preparation method is simple and easy to operate, which is beneficial to popularization and large-scale production.

[0040] The present application uses artificial porcelain sand as aggregate instead of the traditional aggregate with silicon dioxide as the main component, and the artificial porcelain sand has high strength and the main component is aluminum oxide, which can not only improve the strength of the cement adhesive, but also greatly reduce the potential risk of traditional river sand alkali aggregate reaction.

[0041] The present application uses spherical silica powder as the preparation raw material of the base material, which has a nanoscale spherical structure, has a ball effect, and can also synergize with the additive, which not only realizes the self-leveling of the adhesive, reduces manual operation, but also has less loss of fluidity, greatly improves the operability of the cement adhesive.

[0042] And the present application adopts a steam curing system, which has short molding time, greatly reduces the production cycle of the cement adhesive, reduces the inventory pressure, greatly reduces the production cost, realizes the dual goals of quality improvement and cost reduction, and greatly improves and broadens the application and market competitiveness of the cement adhesive. BRIEF DESCRIPTION OF DRAWINGS

[0043] Figure 1The SEM image of the silicon micro powder used in the application. DETAILED DESCRIPTION

[0044] The technical solutions in the embodiments of the application will be described clearly and completely below. The common silicon micro powder used in the following embodiments of the application is purchased from Hubei Siman New Material Co., Ltd., and the common leveling agent is purchased from Shandong Yousuo Chemical Technology Co., Ltd.

[0045] The application provides a self-leveling high-strength cement adhesive, which comprises a base material, an additive and water; the amount of the additive is 0.1wt%-1.4wt% of the base material; and the amount of the water is 16wt%-25wt% of the base material.

[0046] The base material is prepared from the following components by mass percentage:

[0047] The base material is prepared from the following components by mass percentage:

[0048] The additive comprises a polycarboxylic acid compound water reducing agent, a crack resistance agent, a defoaming agent and a leveling agent; and the leveling agent is a polyether modified organic silicon.

[0049] The application further provides a preparation method of the self-leveling high-strength cement adhesive, which comprises the following steps:

[0050] Step 1: according to the above-mentioned proportion, the corresponding mass of the base material, the additive and the water are weighed and prepared for use.

[0051] The base material is prepared from the following components by mass percentage:

[0052] The base material is prepared from the following components by mass percentage:

[0053] It should be noted that the Portland cement used in the application is selected from 525#P I type or P II type cement, and the 525#P I type and P II type cement have high strength and high comprehensive cost performance.

[0054] The present application considers that the aggregate adopted by the prior art is mainly composed of silicon dioxide, and long-term use will cause alkali aggregate reaction, resulting in the risk of material strength damage, therefore, the present application adopts artificial porcelain sand as the aggregate to replace the traditional aggregate mainly composed of silicon dioxide, and the artificial porcelain sand has high strength and the main component is aluminum oxide, which can avoid or reduce the alkali aggregate reaction. The present application also considers that the particle size of the aggregate is too large or too small, which is not conducive to the comprehensive performance of the cementing agent prepared by the artificial porcelain sand, therefore, the present application limits the aluminum content and particle size of the artificial porcelain sand, and requires that the artificial porcelain sand has an aluminum content of ≥80% and a particle size of 30-70 mesh. The artificial porcelain sand can not only improve the strength of the cementing agent, but also greatly reduce the potential risk caused by the traditional river sand alkali aggregate reaction.

[0055] The silicon powder adopted by the present application has a purity of ≥99%, and the silicon powder is spherical and has a particle size of 10-200 nm. The morphology of the spherical silicon powder adopted by the present application is shown in Figure 1 Figure 1 As can be seen, the high-purity silicon dioxide microstructure of the silicon powder adopted by the present application is in the nanometer level of spherical shape, the minimum is 10-20 nanometers, and the maximum is 200 nanometers, all of which are spherical. Such structure gives the silicon dioxide a ball-like effect, and the addition of the silicon dioxide to the cementing agent can make the cementing agent have good self-leveling performance. The spherical silicon powder adopted by the present application and the leveling agent prepared by the present application can synergistically realize the self-leveling of the cementing agent, reduce manual operation, and greatly improve the operability of the cementing agent.

[0056] It should be further pointed out that the additives adopted by the present application include polycarboxylic acid compound water reducing agent, anti-cracking agent, defoaming agent, and leveling agent; and the amount of the additives is 0.1wt%-1.4wt% of the base material; and preferably, the amount of the polycarboxylic acid compound water reducing agent is 0.1wt%-0.3wt% of the base material; the amount of the anti-cracking agent is 0.1wt%-0.3wt% of the base material; the amount of the defoaming agent is 0.1wt%-0.3wt% of the base material; and the amount of the leveling agent is 0.1wt%-0.5wt% of the base material.

[0057] In order to make the prepared cementing agent have better early strength, the polycarboxylic acid compound water reducing agent adopted by the present application is prepared by the following steps: mixing lithium salt into polycarboxylic acid water reducing agent and mixing to obtain, so as to improve the early strength of the cementing agent by adding lithium salt; and wherein the lithium salt is lithium nitrate or lithium carbonate; and the amount of the lithium salt is 15wt%-25wt% of the polycarboxylic acid water reducing agent.

[0058] ​The anti-cracking agent used in the present application is polypropylene fiber to prevent or inhibit the generation of fine cracks on the surface of the prepared cement adhesive.

[0059] In order to improve the defoaming effect, the defoaming agent used in the present application is a hydrocarbon compound with a purity of ≥98%, which can be selected from liquid ethylene glycol or glycerol.

[0060] The polyether-modified silicone used in the present application is prepared by the following steps: S1, uniformly mixing polymethylhydrogen siloxane (PMHS) and polyether F-6 and then performing an addition reaction to obtain a mixture A; S2, uniformly dispersing a catalyst in the mixture A to obtain a mixture B; S3, performing a reflux heating treatment on the mixture B, when the temperature rises to 78-82℃, nitrogen is introduced, then toluene is added, and then the temperature is continuously raised to 105-115℃ for constant temperature reaction for 6-10h, after the reaction is completed, toluene is removed by reduced pressure distillation, and the polyether-modified silicone is obtained. The mass ratio of the polymethylhydrogen siloxane and the polyether F-6 is 1:1.8-2.2; and the mass ratio of the added toluene to the mixture B is 0.15-0.25:1. The catalyst used is chloroplatinic acid isopropyl alcohol solution, and the mass ratio of the catalyst to the mixture A is 1.0wt%-2.0wt%:1. Using chloroplatinic acid isopropyl alcohol solution as the catalyst not only has a low dosage but also has obvious catalytic effect.

[0061] Step 2, uniformly mixing the portland cement, porcelain sand and silicon powder to obtain a base material;

[0062] Step 3, uniformly mixing the base material with the anti-cracking agent, water reducing agent, defoaming agent and leveling agent, adding water and stirring uniformly to obtain the cement adhesive;

[0063] The water is used in an amount of 16wt%-25wt% of the base material.

[0064] In the present application, each preparation raw material is added and mixed according to the above steps to ensure that each component is fully mixed to obtain a self-leveling high-strength cement adhesive for porcelain insulators with uniform components.

[0065] Example 1

[0066] The present embodiment provides a cement adhesive, and its preparation method is as follows:

[0067] 1) According to the following mass percentage ratio, the corresponding mass of each preparation raw material is weighed and prepared:

[0068] 60wt% of portland cement, 30wt% of artificial porcelain sand and 10wt% of high-purity spherical silicon powder.

[0069] 2) Mix the above weighed 60wt% of Portland cement, 30wt% of artificial porcelain sand, and 10wt% of high-purity spherical silica powder to obtain a base material;

[0070] 3) Mix 0.2wt% of polycarboxylic acid compound water reducing agent, 0.1wt% of polypropylene fiber as a crack resistant agent, 0.2wt% of defoaming agent, and 0.3wt% of leveling agent to the total weight of the base material, and then mix 18wt% of water to the total amount of the base material to obtain a self-leveling high-strength cement adhesive for porcelain insulators.

[0071] The adhesive is glued into the porcelain piece, and steam curing is performed at a temperature of 40-50°C for 6h, and the adhesive has excellent strength performance, with a 3d compressive strength of 117.1MPa, a 3d flexural strength of 14.1MPa, a dry shrinkage rate of 0.03%, an elastic modulus of 41.8GPa, an 11d compressive strength of 124.6MPa, a flexural strength of 6.2MPa, a dry shrinkage rate of 0.06%, and an elastic modulus of 42.1GPa. In addition, the autoclave expansion rate is -0.026%, which is lower than the standard requirement of less than 0.1%, and the electromechanical failure strength is 668MPa, and the failure mode is foot long.

[0072] Example 2

[0073] The present embodiment provides a cement adhesive, and the preparation method thereof is as follows:

[0074] 1) The respective raw materials are weighed according to the following mass percentage ratio:

[0075] 60wt% of Portland cement, 32wt% of artificial porcelain sand, and 8wt% of high-purity spherical silica powder.

[0076] 2) Mix the above weighed 60wt% of Portland cement, 30wt% of artificial porcelain sand, and 10wt% of high-purity spherical silica powder to obtain a base material;

[0077] 3) Mix 0.2wt% of polycarboxylic acid compound water reducing agent, 0.1wt% of polypropylene fiber as a crack resistant agent, 0.2wt% of defoaming agent, and 0.3wt% of leveling agent to the total weight of the base material, and then mix 18wt% of water to the total amount of the base material to obtain a self-leveling high-strength cement adhesive for porcelain insulators.

[0078] The adhesive is glued into the porcelain piece, and the adhesive strength performance is excellent at a temperature of 40-50℃ for steam curing for 6h, with 3d compressive strength of 112.2MPa, 3d flexural strength of 13.8MPa, dry shrinkage of 0.03%, elastic modulus of 45.5GPa, 11d compressive strength of 120.2MPa, flexural strength of 15.3MPa, dry shrinkage of 0.06%, and elastic modulus of 45.9GPa. In addition, the autoclaved expansion rate is -0.026%, which is lower than the standard requirement of less than 0.1%, and the electromechanical failure strength is 674MPa, and the failure mode is foot long.

[0079] Example 3

[0080] The embodiment provides a cement adhesive, and a preparation method thereof is as follows:

[0081] 1) The preparation raw materials are weighed according to the following mass percentage ratio, and are ready for use:

[0082] 60wt% of silicate cement, 35wt% of artificial porcelain sand, and 5wt% of high-purity spherical silicon micro powder.

[0083] 2) The above weighed 60wt% of silicate cement, 30wt% of artificial porcelain sand, and 10wt% of high-purity spherical silicon micro powder are uniformly mixed to obtain a base material;

[0084] 3) 0.2wt% of polycarboxylic acid compound water reducing agent, 0.1wt% of polypropylene fiber as a crack resistance agent, 0.2wt% of defoaming agent, and 0.3wt% of leveling agent are added to the total weight of the base material, and are uniformly mixed; then 18wt% of water of the total amount of the base material is added and stirred to obtain a self-leveling high-strength cement adhesive for porcelain insulators.

[0085] The adhesive is glued into the porcelain piece, and the adhesive strength performance is excellent at a temperature of 40-50℃ for steam curing for 6h, with 3d compressive strength of 115.1MPa, 3d flexural strength of 13.5MPa, dry shrinkage of 0.03%, elastic modulus of 46.9GPa, 11d compressive strength of 121.3MPa, flexural strength of 15.8MPa, dry shrinkage of 0.04%, and elastic modulus of 47.1GPa. In addition, the autoclaved expansion rate is -0.025%, which is lower than the standard requirement of less than 0.1%, and the electromechanical failure strength is 672MPa, and the failure mode is foot long.

[0086] Example 4

[0087] The embodiment provides a cement adhesive, and a preparation method thereof is as follows:

[0088] 1) The preparation raw materials are weighed according to the following mass percentage ratio, and are ready for use:

[0089] 0wt% of Portland cement, 40wt% of artificial porcelain sand, 10wt% of high-purity spherical silicon micro powder.

[0090] 2) Mix the weighed 60wt% of Portland cement, 30wt% of artificial porcelain sand, and 10wt% of high-purity spherical silicon micro powder to obtain a base material;

[0091] 3) Add 0.2wt% of polycarboxylic acid compound water reducing agent, 0.1wt% of polypropylene fiber as a crack resistance agent, 0.2wt% of a defoaming agent, and 0.3wt% of a leveling agent to the total weight of the base material, and mix uniformly; then add 17wt% of water to the total amount of the base material, and mix uniformly to obtain a self-leveling high-strength cement adhesive for porcelain insulators.

[0092] The adhesive is glued into the porcelain piece, and steam curing is performed at a temperature of 40-50°C for 6h, and the adhesive has excellent strength performance, with a 3d compressive strength of 118.1MPa, a 3d flexural strength of 12.9MPa, a dry shrinkage rate of 0.02%, an elastic modulus of 47.2GPa, an 11d compressive strength of 122.9MPa, a flexural strength of 14.7MPa, a dry shrinkage rate of 0.04%, and an elastic modulus of 47.5GPa. In addition, the autoclaved expansion rate is -0.025%, which is lower than the standard requirement of less than 0.1%, and the electromechanical failure strength is 668MPa, and the failure mode is foot long.

[0093] Example 5

[0094] The present embodiment provides a cement adhesive, and the preparation method thereof is as follows:

[0095] 1) The respective raw materials are weighed according to the following mass percentage ratio:

[0096] 50wt% of Portland cement, 45wt% of artificial porcelain sand, and 5wt% of high-purity spherical silicon micro powder.

[0097] 2) Mix the weighed 60wt% of Portland cement, 30wt% of artificial porcelain sand, and 10wt% of high-purity spherical silicon micro powder to obtain a base material;

[0098] 3) Add 0.2wt% of polycarboxylic acid compound water reducing agent, 0.1wt% of polypropylene fiber as a crack resistance agent, 0.2wt% of a defoaming agent, and 0.3wt% of a leveling agent to the total weight of the base material, and mix uniformly; then add 17wt% of water to the total amount of the base material, and mix uniformly to obtain a self-leveling high-strength cement adhesive for porcelain insulators.

[0099] The adhesive is glued into the porcelain piece, and the strength performance of the adhesive is excellent after steam curing at 40-50℃ for 6h, with 3d compressive strength of 108.5MPa, 3d flexural strength of 12.8MPa, dry shrinkage of 0.02%, elastic modulus of 47.8GPa, 11d compressive strength of 123.8MPa, flexural strength of 13.2MPa, dry shrinkage of 0.04%, and elastic modulus of 48.3GPa. In addition, the autoclave expansion rate thereof is -0.024%, which is lower than the standard requirement of less than 0.1%, and the electromechanical failure strength is 664MPa, and the failure mode is foot long.

[0100] Example 6

[0101] The present embodiment provides a cement adhesive, and the preparation method thereof is as follows:

[0102] 1) The respective raw materials are weighed according to the following mass percentage ratio:

[0103] 30wt% of Portland cement, 60wt% of artificial porcelain sand, and 10wt% of high-purity spherical silicon micro powder.

[0104] 2) The weighed 60wt% of Portland cement, 30wt% of artificial porcelain sand, and 10wt% of high-purity spherical silicon micro powder are uniformly mixed to obtain a base material;

[0105] 3) 0.2wt% of polycarboxylic acid compound water reducing agent, 0.1wt% of polypropylene fiber as a crack resistance agent, 0.2wt% of defoaming agent, and 0.3wt% of leveling agent are added to the total weight of the base material, and then uniformly mixed; then 16wt% of water is added to the total amount of the base material and stirred to obtain a self-leveling high-strength cement adhesive for porcelain insulators.

[0106] The adhesive is glued into the porcelain piece, and the strength performance of the adhesive is excellent after steam curing at 40-50℃ for 6h, with 3d compressive strength of 123.8MPa, 3d flexural strength of 142.2MPa, dry shrinkage of 0.02%, elastic modulus of 49.3GPa, 11d compressive strength of 34.2MPa, flexural strength of 9.8MPa, dry shrinkage of 0.05%, and elastic modulus of 49.9GPa. In addition, the autoclave expansion rate thereof is -0.023%, which is lower than the standard requirement of less than 0.1%, and the electromechanical failure strength is 682MPa, and the failure mode is foot long.

[0107] Comparative Example 1

[0108] The difference between the present comparative example and Example 1 is only that:

[0109] In the present comparative example, the artificial porcelain sand in Example 1 is replaced by ordinary river sand.

[0110] Comparative Example 2

[0111] The present comparative example differs from Example 1 only in that:

[0112] The present comparative example replaces the high-purity spherical silicon micro-powder of Example 1 with ordinary silicon micro-powder having a purity of 92%.

[0113] Comparative Example 3

[0114] The present comparative example differs from Example 1 only in that:

[0115] The present comparative example replaces the high-purity spherical silicon micro-powder of Example 1 with ordinary silicon micro-powder having a purity of 92%;

[0116] and the comparative example replaces the polyether-modified organosilicon leveling agent of Example 1 with a commercially available ordinary leveling agent;

[0117] Experimental Section

[0118] The mechanical properties of the cementitious adhesives prepared in Examples 1-6 and Comparative Examples 1-3 were tested, and the test results are shown in Table 1.

[0119] Table 1: Test results of the mechanical properties of the cementitious adhesives prepared in Examples 1-6 and Comparative Examples 1-3

[0120]

[0121]

[0122] Referring to the test results in Table 1, it can be seen from a comparison of Examples 1-6 and Comparative Example 1 that the cementitious adhesives for porcelain insulators prepared in Examples 1-6 all have high compressive strength, high flexural strength, and fast setting time, which can greatly improve the site turnover period of the product and greatly improve the production efficiency.

[0123] From the test results of Comparative Example 1 and Example 1, it can be seen that the water addition amount for achieving self-leveling in Comparative Example 1 is 24% of the total amount of the base material, while the water addition amount in Example 1 is 18%. The overall performance of Comparative Example 1 is significantly lower than that of Example 1, with a 3d compressive strength of 88.5 MPa, a 3d flexural strength of 8.9 MPa, a drying shrinkage of 0.04%, an elastic modulus of 34.6 GPa, an 11d compressive strength of 95.5 MPa, a flexural strength of 11.4 MPa, a drying shrinkage of 0.09%, and an elastic modulus of 37.2 GPa. Compared with the 11d performance of Example 1, the 11d compressive strength is reduced by 29.1 MPa, and the flexural strength is reduced by 5.2 MPa, but the elastic modulus is reduced by 7.2 MPa, and the drying shrinkage is increased by 0.03%. In addition, the autoclaved expansion rate is -0.032%, which is lower than the standard requirement of 0.1%, and the electromechanical failure strength is 638 MPa, and the failure mode is all foot length.

[0124] From the test results of Comparative Example 2 and Example 1, it can be seen that the water addition amount for achieving self-leveling in Comparative Example 2 is 24% of the total amount, while the water addition amount in Example 1 is 18%, and the comprehensive performance of Comparative Example 2 is obviously lower than that of Example 1, with 3d compressive strength of 92.5 MPa, 3d flexural strength of 11.2 MPa, dry shrinkage of 0.04%, elastic modulus of 36.8 GPa, 11d compressive strength of 105.2 MPa, flexural strength of 12.6 MPa, dry shrinkage of 0.08%, and elastic modulus of 37.1 GPa. Compared with the 11d performance of Example 1, the 11d compressive strength of Comparative Example 2 is reduced by 19.4 MPa, the flexural strength is reduced by 3.1 MPa, but the elastic modulus is reduced by 5.0 MPa, and the dry shrinkage is increased by 0.02%. In addition, the autoclaved expansion rate thereof is -0.028%, which is lower than the standard requirement of less than 0.1%, and the electromechanical failure strength is 657 MPa, and the failure mode is foot long.

[0125] From the test results of Comparative Example 3 and Example 1, it can be seen that the water addition amount for achieving self-leveling in Comparative Example 3 is 25% of the total amount, while the water addition amount in Example 1 is 18%, and the comprehensive performance of Comparative Example 3 is obviously lower than that of Example 1, with 3d compressive strength of 82.3 MPa, 3d flexural strength of 7.6 MPa, dry shrinkage of 0.05%, elastic modulus of 32.4 GPa, 11d compressive strength of 88.5 MPa, flexural strength of 7.8 MPa, dry shrinkage of 0.09%, and elastic modulus of 32.6 GPa. Compared with the 11d performance of Example 1, the 11d compressive strength of Comparative Example 3 is reduced by 36.1 MPa, the flexural strength is reduced by 9.5 MPa, but the elastic modulus is reduced by 9.5 MPa, and the dry shrinkage is increased by 0.03%. In addition, the autoclaved expansion rate thereof is -0.028%, which is lower than the standard requirement of less than 0.1%, and the electromechanical failure strength is 626 MPa, and the failure mode is foot long.

[0126] Obviously, the above-described examples are only some of the embodiments of the present application, but not all the embodiments. Based on the examples in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of protection of the present application.

Claims

1. A self-leveling high-strength cement mortar for porcelain insulators, characterized in that, The base material, the additive, and water; the additive is 0.1wt%-1.4wt% of the base material; the water is 16wt%-25wt% of the base material; The base material is prepared from the following components by mass percentage: Silicate cement 40wt%-60wt%, porcelain sand 30wt%-60wt%, and silicon powder 3wt%-10wt%, and the total amount of each component is 100wt%; The additive includes polycarboxylic acid compound water reducing agent, anti-cracking agent, defoaming agent, and leveling agent; and the leveling agent is polyether modified silicone; The polyether modified silicone is prepared by the following steps: S1, mixing polymethylhydrogen siloxane and polyether F-6 to obtain mixture A; The mass ratio of the polymethylhydrogen siloxane and the polyether F-6 is 1:1.8-2.2; S2, uniformly dispersing the catalyst in the mixture A to obtain mixture B; S3, refluxing and heating the mixture B, when the temperature rises to 78-82℃, nitrogen is introduced, then toluene is added, and then the temperature is continuously raised to 105-115℃ for constant temperature reaction for 6-10h, after the reaction is completed, the toluene is removed, and the polyether modified silicone is obtained; The purity of the silicon powder is ≥99%, the silicon powder is spherical and the particle size is 10-200nm; The amount of the leveling agent is 0.1wt%-0.5wt% of the base material.

2. The self-leveling high-strength cement mortar for porcelain insulators according to claim 1, characterized in that, The amount of the polycarboxylic acid compound water reducing agent is 0.1wt%-0.3wt% of the base material; The amount of the anti-cracking agent is 0.1wt%-0.3wt% of the base material; The amount of the defoaming agent is 0.1wt%-0.3wt% of the base material.

3. The self-leveling high-strength cementing agent for porcelain insulators according to claim 1, characterized in that, The catalyst is isopropanol solution of chloroplatinic acid; the mass concentration of chloroplatinic acid in the isopropanol solution is 1wt%; The mass ratio of the catalyst and the mixture A is 1.0wt%-2.0wt%:

1.

4. The self-leveling high-strength cementing agent for porcelain insulators according to claim 1, characterized in that, The mass ratio of the toluene and the mixture B is 0.15-0.25:

1.

5. The self-leveling high-strength cementing agent for porcelain insulators according to claim 1, characterized in that, The silicate cement is 525# P I type or P II type cement; The porcelain sand is porcelain sand with aluminum content ≥80% and particle size of 30-70 mesh.

6. The self-leveling high strength cement mortar for porcelain insulators according to claim 1, characterized in that, The polycarboxylic acid compound water reducing agent is prepared by the following steps: Mixing lithium salt into polycarboxylic acid water reducing agent to obtain the polycarboxylic acid compound water reducing agent; The lithium salt is lithium nitrate or lithium carbonate; and the amount of the lithium salt is 15wt%-25wt% of the polycarboxylic acid water reducing agent.

7. The self-leveling high-strength cementing agent for porcelain insulators according to claim 1, characterized in that, The anti-cracking agent is polypropylene fiber, and the length of the polypropylene fiber is 5.5-6.56mm and the aspect ratio is 5-10.

8. The self-leveling high-strength cementing agent for porcelain insulators according to claim 1, characterized in that, The defoaming agent is hydrocarbon with purity ≥98%.

9. A method for preparing the self-leveling high-strength cementing agent for porcelain insulators according to any one of claims 1-8, characterized in that, The following steps are included: Step 1, weighing the corresponding mass of the base material, the additive, and the water according to the above ratio for standby; wherein the base material is weighed according to the following mass percentage ratio: Silicate cement 40wt%-60wt%, porcelain sand 30wt%-60wt%, and silicon powder 3wt%-10wt%; Step 2, mixing the portland cement, porcelain sand and silicon powder to obtain a base; Step 3, mixing the base with the auxiliary agent, and adding water to stir uniformly, thus obtaining the self-leveling high-strength cement adhesive for porcelain insulators.

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