Organic-inorganic composite conductive cement-based material, preparation method and application thereof
By introducing conductive hydrogel precursors and conductive polymer particles into cement-based materials to form an interpenetrating network structure, the problem of balancing conductivity and mechanical properties of cement-based materials is solved, achieving both high-efficiency conductivity and improved flexural strength.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- SOUTH CHINA UNIV OF TECH
- Filing Date
- 2023-11-30
- Publication Date
- 2026-06-02
AI Technical Summary
When conductive fillers are introduced into existing cement-based materials, uneven dispersion or agglomeration is likely to occur, resulting in uneven conductive pathways, which affects mechanical properties and makes it difficult to simultaneously meet the requirements of excellent electrical and mechanical properties.
An organic-inorganic composite conductive cement-based material is used. By introducing a conductive hydrogel precursor solution into the cement-based material, an interpenetrating network structure is formed. Combined with conductive polymer particles, a uniform conductive pathway is constructed, and the bonding with the cement matrix is enhanced by hydroxyl, carboxyl and other groups.
It achieves a balance between electrical conductivity and mechanical properties, reduces resistivity, improves flexural strength, enhances material stability and continuous conductivity, and is suitable for large-scale application.
Smart Images
Figure BDA0004579377250000031 
Figure BDA0004579377250000041 
Figure BDA0004579377250000051
Abstract
Description
Technical Field
[0001] This invention relates to the field of building materials technology, specifically to an organic-inorganic composite conductive cement-based material, its preparation method, and its application. Background Technology
[0002] Cement-based materials possess excellent mechanical properties, simple preparation processes, and low costs, making them the most widely used basic building materials. With changing economic and social needs, the intelligentization of cement-based materials has become a research hotspot. Studies have found that the electrical conductivity of cement-based materials is a prerequisite for realizing their sensitivity and heat-sensitivity functions.
[0003] Currently, the conductivity of cement-based materials is mainly achieved by introducing conductive fillers (e.g., metallic conductive materials such as steel fibers and steel shavings; carbon-based conductive materials such as carbon nanotubes, carbon fibers, graphite powder, and carbon black). On one hand, direct contact between conductive fillers forms conductive pathways; on the other hand, when the conductive fillers are not in direct contact (requiring a sufficiently small distance between them), electrons can tunnel through the hydration products between the fillers, thus forming complete conductive pathways and ultimately achieving conductivity in the cement-based material. Therefore, constructing conductive pathways within cement-based materials is a reliable guarantee for achieving conductivity. However, due to significant differences in composition and density between conductive fillers and cement-based materials, conductive fillers are prone to uneven dispersion or even agglomeration. In such cases, to construct conductive pathways, it is necessary to increase the amount of conductive filler, but excessively high amounts can lead to a significant decrease in the mechanical properties of cement-based materials, making it difficult to fully meet the requirements of practical applications.
[0004] Therefore, developing a cement-based composite material that combines excellent electrical conductivity and excellent mechanical properties is of great significance. Summary of the Invention
[0005] The purpose of this invention is to provide an organic-inorganic composite conductive cement-based material, its preparation method, and its application.
[0006] The technical solution adopted in this invention is:
[0007] An organic-inorganic composite conductive cement-based material comprises the following raw materials in parts by weight:
[0008] Cementitious material: 100 parts;
[0009] Conductive hydrogel precursor solution: 5 parts to 30 parts;
[0010] Crosslinking agent: 0.02 parts to 0.08 parts;
[0011] Water: 25 to 50 parts;
[0012] The conductive hydrogel precursor solution comprises the following components in parts by weight:
[0013] Hydrogel monomer: 100 parts;
[0014] Conductive polymer particles: 0.5 parts to 2 parts;
[0015] Initiator: 0.1 to 2 parts;
[0016] Water: 50 to 180 parts.
[0017] Preferably, the cementing material is silicate cement or a mixture of silicate cement and at least one of blast furnace ore powder, steel slag, fly ash, and limestone powder.
[0018] Preferably, the crosslinking agent is at least one of N,N-dimethylacrylamide, N,N'-methylenebisacrylamide, and formaldehyde.
[0019] Preferably, the hydrogel monomer is at least one of acrylamide, sodium acrylate, and ethylene glycol.
[0020] Preferably, the conductive polymer particles are polypyrrole particles.
[0021] Preferably, the polypyrrole particles are prepared by the following method: adding an aqueous solution of polypyrrole and an aqueous solution of an initiator dropwise into a hydrochloric acid solution, reacting in an ice bath for 3 to 10 hours, and then filtering, washing and drying to obtain polypyrrole particles.
[0022] Preferably, the mass ratio of polypyrrole in the polypyrrole aqueous solution to initiator in the initiator aqueous solution is 1:0.02 to 0.10.
[0023] Preferably, the number-average molecular weight of the polypyrrole in the polypyrrole aqueous solution is 8000 to 12000.
[0024] Preferably, the initiator in the initiator aqueous solution is at least one of potassium persulfate and sodium bisulfite.
[0025] Preferably, the concentration of the initiator aqueous solution is 0.025 mol / L to 0.050 mol / L.
[0026] Preferably, the concentration of the hydrochloric acid solution is 0.2 mol / L to 0.8 mol / L.
[0027] Preferably, the particle size of the polypyrrole particles is 30 μm to 100 μm.
[0028] Preferably, the initiator is at least one selected from potassium persulfate, ammonium persulfate, ferrous sulfate, and sodium bisulfite.
[0029] Preferably, the resistivity of the organic-inorganic composite conductive cement-based material is 0.5 Ω·m to 1.5 Ω·m, the compressive strength is 35 MPa to 60 MPa, and the flexural strength is 15 MPa to 25 MPa.
[0030] A method for preparing an organic-inorganic composite conductive cement-based material as described above includes the following steps:
[0031] 1) Mix the hydrogel monomer, conductive polymer particles, initiator and water to obtain a conductive hydrogel precursor solution;
[0032] 2) Mix the cementitious material, conductive hydrogel precursor solution, crosslinking agent and water, then inject into the mold for molding, and then demold and cure at high temperature and room temperature to obtain organic-inorganic composite conductive cement-based material.
[0033] Preferably, the mixing method in step 1) is stirring, and the stirring time is 20 min to 80 min.
[0034] Preferably, the mixing method in step 2) is stirring, and the stirring time is 4 min to 10 min.
[0035] Preferably, the high-temperature curing in step 2) is carried out in an environment with a temperature of 50℃ to 85℃, and the curing time is 2h to 8h.
[0036] Preferably, the room temperature curing in step 2) is carried out in an environment with a temperature of 20℃~25℃, and the curing time is 5 days~10 days.
[0037] Application of an organic-inorganic composite conductive cement-based material as described above in the fabrication of piezoelectric sensors.
[0038] The beneficial effects of this invention are: the organic-inorganic composite conductive cement-based material of this invention has both excellent electrical conductivity and excellent mechanical properties, and its preparation method is simple and the production cost is low, making it suitable for large-scale promotion and application.
[0039] Specifically:
[0040] 1) In the organic-inorganic composite conductive cement-based material of the present invention, the conductive hydrogel network is formed synchronously with the hydration products, and an interpenetrating network structure is constructed. While ensuring the uniform distribution of conductive pathways, the flexural strength of the cement-based material is significantly improved.
[0041] 2) In the organic-inorganic composite conductive cement-based material of the present invention, the conductive polymer network is continuously distributed in the cement-based material, which is conducive to the passage of current, thereby achieving high-efficiency conductivity and reducing the resistivity of the cement-based material;
[0042] 3) The conductive hydrogel surface of the organic-inorganic composite conductive cement-based material of the present invention is rich in hydroxyl, carboxyl and other groups, which can chelate with metal cations through hydrogen bonds, thereby enhancing the stable bonding between the conductive hydrogel and the cement matrix and reducing the loss of mechanical properties of the cement-based material. Detailed Implementation
[0043] The present invention will be further explained and described below with reference to specific embodiments.
[0044] Example 1:
[0045] An organic-inorganic composite conductive cement-based material, the raw material composition of which is shown in the table below:
[0046] Table 1. Raw material composition of an organic-inorganic composite conductive cementitious material
[0047] raw material Quality cementing materials 100 Conductive hydrogel precursor solution 25 N,N-Dimethylacrylamide 0.06 water 50
[0048] Note:
[0049] Cementing material: Silicate cement, strength grade 52.5R.
[0050] The raw material composition of the conductive hydrogel precursor solution is shown in the table below:
[0051] Table 2. Raw material composition of conductive hydrogel precursor solution
[0052]
[0053]
[0054] The preparation method of the above-mentioned organic-inorganic composite conductive cement-based material is as follows:
[0055] 1) 50 mL of 30% polypyrrole (number average molecular weight of 8000) aqueous solution and 25 mL of 0.04 mol / L potassium persulfate aqueous solution were added dropwise to 9 mL of 0.3 mol / L hydrochloric acid solution. The mixture was then placed in an ice bath and reacted for 8 h. After filtration, washing and drying, polypyrrole particles were obtained.
[0056] 2) Mix acrylamide, polypyrrole particles, ammonium persulfate and water for 80 min to obtain a conductive hydrogel precursor solution;
[0057] 3) Mix the cementitious material, conductive hydrogel precursor solution, N,N-dimethylacrylamide and water for 5 minutes, then pour the mixture into a mold for molding. After demolding, cure the mixture at 55°C for 4 hours, and then at 20°C for 7 days (mixing, molding, demolding and curing are carried out in accordance with "GB / T 17671-2021 Cement Mortar Strength Test Method"). The organic-inorganic composite conductive cement-based material is then obtained.
[0058] Performance testing:
[0059] Tests showed that the resistivity of the organic-inorganic composite conductive cement-based material in this embodiment is 0.5 Ω·m, the compressive strength is 50 MPa, and the flexural strength is 20 MPa.
[0060] Note:
[0061] Resistivity: Tested in accordance with "GB / T 1692-2008 Determination of Resistivity of Vulcanized Rubber Insulation".
[0062] Compressive strength and flexural strength: Tested in accordance with "GB / T 17671-2021 Cement Mortar Strength Test Method".
[0063] Example 2:
[0064] An organic-inorganic composite conductive cement-based material, the raw material composition of which is shown in the table below:
[0065] Table 3. Raw material composition of an organic-inorganic composite conductive cement-based material
[0066] raw material Quality cementing materials 100 Conductive hydrogel precursor solution 8 N,N'-Methylenebisacrylamide 0.03 water 35
[0067] Note:
[0068] Cementitious material: It is a mixture of silicate cement (strength grade 52.5R), blast furnace ore powder (average particle size 6μm) and fly ash (particle size 3μm~15μm) in a mass ratio of 5:3:2.
[0069] The raw material composition of the conductive hydrogel precursor solution is shown in the table below:
[0070] Table 4. Raw material composition of conductive hydrogel precursor solution
[0071]
[0072] The preparation method of the above-mentioned organic-inorganic composite conductive cement-based material is as follows:
[0073] 1) 50 mL of 30% polypyrrole (number average molecular weight 9200) aqueous solution and 100 mL of 0.05 mol / L ferrous sulfate aqueous solution were added dropwise to 9 mL of 0.25 mol / L hydrochloric acid solution. The mixture was then placed in an ice bath and reacted for 6 h. After filtration, washing and drying, polypyrrole particles were obtained.
[0074] 2) Mix acrylamide, polypyrrole particles, potassium persulfate and water for 40 min to obtain a conductive hydrogel precursor solution;
[0075] 3) Mix the cementitious material, conductive hydrogel precursor solution, N,N'-methylenebisacrylamide and water for 8 minutes, then pour the mixture into a mold for molding. After demolding, cure the mixture at 80℃ for 6 hours, and then at 23℃ for 7 days (mixing, molding, demolding and curing are carried out in accordance with "GB / T 17671-2021 Cement Mortar Strength Test Method"). The organic-inorganic composite conductive cement-based material is then obtained.
[0076] Performance testing (testing method is the same as in Example 1):
[0077] Tests showed that the resistivity of the organic-inorganic composite conductive cement-based material in this embodiment is 1.2 Ω·m, the compressive strength is 40 MPa, and the flexural strength is 18 MPa.
[0078] Example 3:
[0079] An organic-inorganic composite conductive cement-based material, the raw material composition of which is shown in the table below:
[0080] Table 5. Raw material composition of an organic-inorganic composite conductive cement-based material
[0081] raw material Quality cementing materials 100 Conductive hydrogel precursor solution 10 N,N-Dimethylacrylamide 0.05 water 40
[0082] Note:
[0083] Cementing material: Silicate cement, strength grade 42.5R.
[0084] The raw material composition of the conductive hydrogel precursor solution is shown in the table below:
[0085] Table 6. Raw material composition of conductive hydrogel precursor solution
[0086]
[0087] The preparation method of the above-mentioned organic-inorganic composite conductive cement-based material is as follows:
[0088] 1) 50 mL of 30% polypyrrole (number average molecular weight of 10000) aqueous solution and 25 mL of 0.04 mol / L potassium persulfate aqueous solution were added dropwise to 9 mL of 0.3 mol / L hydrochloric acid solution. The mixture was then placed in an ice bath and reacted for 5 h. After filtration, washing and drying, polypyrrole particles were obtained.
[0089] 2) Sodium acrylate, polypyrrole particles, ferrous sulfate and water were stirred and mixed for 60 min to obtain a conductive hydrogel precursor solution;
[0090] 3) Mix the cementitious material, conductive hydrogel precursor solution, N,N-dimethylacrylamide and water for 6 minutes, then pour the mixture into a mold for molding. After demolding, cure the mixture at 65℃ for 5 hours, and then at 20℃ for 7 days (mixing, molding, demolding and curing are carried out in accordance with "GB / T 17671-2021 Cement Mortar Strength Test Method"). The organic-inorganic composite conductive cement-based material is then obtained.
[0091] Performance testing (testing method is the same as in Example 1):
[0092] Tests showed that the resistivity of the organic-inorganic composite conductive cement-based material in this embodiment is 0.8 Ω·m, the compressive strength is 56 MPa, and the flexural strength is 23 MPa.
[0093] Example 4:
[0094] An organic-inorganic composite conductive cement-based material, the raw material composition of which is shown in the table below:
[0095] Table 7. Raw material composition of an organic-inorganic composite conductive cementitious material
[0096]
[0097]
[0098] Note:
[0099] Cementitious material: It is a mixture of silicate cement (strength grade 42.5R), blast furnace ore powder (average particle size 6μm) and fly ash (particle size 3μm~15μm) in a mass ratio of 5:3:2.
[0100] The raw material composition of the conductive hydrogel precursor solution is shown in the table below:
[0101] Table 8. Raw material composition of conductive hydrogel precursor solution
[0102]
[0103] The preparation method of the above-mentioned organic-inorganic composite conductive cement-based material is as follows:
[0104] 1) 50 mL of 30% polypyrrole (number average molecular weight 11000) aqueous solution and 100 mL of 0.05 mol / L ferrous sulfate aqueous solution were added dropwise to 9 mL of 0.25 mol / L hydrochloric acid solution. The mixture was then placed in an ice bath and reacted for 7.5 h. After filtration, washing and drying, polypyrrole particles were obtained.
[0105] 2) Sodium acrylate, polypyrrole particles, sodium bisulfite and water were stirred and mixed for 50 min to obtain a conductive hydrogel precursor solution;
[0106] 3) Mix the cementitious material, conductive hydrogel precursor solution, N,N'-methylenebisacrylamide and water for 10 minutes, then pour the mixture into a mold for molding. After demolding, cure the mixture at 70°C for 3 hours, and then at 23°C for 7 days (mixing, molding, demolding and curing are carried out in accordance with "GB / T 17671-2021 Cement Mortar Strength Test Method"). The organic-inorganic composite conductive cement-based material is then obtained.
[0107] Performance testing (testing method is the same as in Example 1):
[0108] Tests showed that the resistivity of the organic-inorganic composite conductive cement-based material in this embodiment is 1.1 Ω·m, the compressive strength is 53 MPa, and the flexural strength is 21 MPa.
[0109] Example 5:
[0110] An organic-inorganic composite conductive cement-based material, the raw material composition of which is shown in the table below:
[0111] Table 9. Raw material composition of an organic-inorganic composite conductive cementitious material
[0112] raw material Quality cementing materials 100 Conductive hydrogel precursor solution 22 formaldehyde 0.05 water 50
[0113] Note:
[0114] Cementitious material: It is a mixture of silicate cement (strength grade 52.5R), blast furnace ore powder (average particle size 6μm) and steel slag (particle size 5μm~30μm) in a mass ratio of 5:3:2.
[0115] The raw material composition of the conductive hydrogel precursor solution is shown in the table below:
[0116] Table 10. Raw material composition of conductive hydrogel precursor solution
[0117]
[0118] The preparation method of the above-mentioned organic-inorganic composite conductive cement-based material is as follows:
[0119] 1) 50 mL of 30% polypyrrole (number average molecular weight 12000) aqueous solution and 100 mL of 0.05 mol / L ferrous sulfate aqueous solution were added dropwise to 9 mL of 0.3 mol / L hydrochloric acid solution. The mixture was then placed in an ice bath and reacted for 4 h. After filtration, washing and drying, polypyrrole particles were obtained.
[0120] 2) Mix ethylene glycol, polypyrrole particles, potassium persulfate and water for 65 min to obtain a conductive hydrogel precursor solution;
[0121] 3) Mix the cementitious material, conductive hydrogel precursor solution, formaldehyde and water for 7 minutes, then pour the mixture into a mold for molding. After demolding, cure the mixture in an environment at 60℃ for 5 hours, and then cure it in an environment at 25℃ for 7 days (mixing, molding, demolding and curing are carried out in accordance with "GB / T 17671-2021 Cement Mortar Strength Test Method"). The organic-inorganic composite conductive cement-based material is obtained.
[0122] Performance testing (testing method is the same as in Example 1):
[0123] Tests showed that the resistivity of the organic-inorganic composite conductive cement-based material in this embodiment is 0.6 Ω·m, the compressive strength is 45 MPa, and the flexural strength is 16 MPa.
[0124] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.
Claims
1. An organic-inorganic composite conductive cement-based material, characterized in that, Made from the following raw materials in parts by weight: Cementitious material: 100 parts; Conductive hydrogel precursor solution: 5 parts to 30 parts; Crosslinking agent: 0.02 parts to 0.08 parts; Water: 25 to 50 parts; The cementing material is silicate cement or a mixture of silicate cement and at least one of blast furnace ore powder, steel slag, fly ash, and limestone powder. The conductive hydrogel precursor solution is composed of the following components in parts by weight: Hydrogel monomer: 100 parts; Conductive polymer particles: 0.5 parts to 2 parts; Initiator: 0.1 to 2 parts; Water: 50 to 180 parts; The hydrogel monomer is at least one of acrylamide, sodium acrylate, and ethylene glycol; The conductive polymer particles are polypyrrole particles; The particle size of the polypyrrole particles is 30μm to 100μm; The organic-inorganic composite conductive cementitious material is prepared by a method including the following steps: 1) mixing hydrogel monomers, conductive polymer particles, initiators and water to obtain a conductive hydrogel precursor solution; 2) mixing cementitious materials, conductive hydrogel precursor solution, crosslinking agents and water, then injecting the mixture into a mold for molding, and then demolding and curing at high temperature and room temperature to obtain the organic-inorganic composite conductive cementitious material.
2. The organic-inorganic composite conductive cement-based material according to claim 1, characterized in that: The crosslinking agent is at least one of N,N-dimethylacrylamide, N,N'-methylenebisacrylamide, and formaldehyde.
3. The organic-inorganic composite conductive cement-based material according to claim 1, characterized in that: The polypyrrole particles are prepared by the following method: polypyrrole aqueous solution and initiator aqueous solution are added dropwise to hydrochloric acid solution, and then reacted in an ice bath for 3 to 10 hours. After filtration, washing and drying, polypyrrole particles are obtained.
4. The organic-inorganic composite conductive cement-based material according to claim 1 or 2, characterized in that: The initiator is at least one of potassium persulfate, ammonium persulfate, ferrous sulfate, and sodium bisulfite.
5. The application of an organic-inorganic composite conductive cement-based material as described in any one of claims 1 to 4 in the preparation of piezoelectric sensors.