Composite green building template and preparation method thereof

Abstract

The invention relates to a composite green building template and a preparation method thereof, and belongs to the technical field of building materials. Polypropylene particles, glass fibers, a silane coupling agent, talcum powder, a reinforcing agent and an antioxidant serve as raw materials, the composite green building template is prepared, the polypropylene particles and the reinforcing agent are ground and smashed, then the mixed powder, the glass fibers, the silane coupling agent, the talcum powder and the antioxidant are stirred and mixed together, a prefabricated material is obtained, and the prefabricated material is subjected to heat treatment to obtain the composite green building template. Finally, the prefabricated material is subjected to hot pressing sintering, and the composite green building formwork is obtained. According to the composite green building template, the polypropylene-glass fiber composite material is used, use of wood is reduced, low carbon and environment friendliness are achieved, and the prepared building template has good impact resistance and tensile strength, is not prone to deformation and has excellent flame retardance.

Description

Technical Field

[0001] The present invention belongs to the technical field of building materials, and in particular relates to a composite green building template and a preparation method thereof. Background Art

[0002] A building formwork is a temporary support structure, fabricated into the desired shape according to design requirements. It allows concrete structures and components to be formed and maintained in their desired positions and dimensions, while also bearing the formwork's own weight and external loads. It serves as the formwork and support for concrete pouring, and is crucial for ensuring the quality, safety, and progress of concrete projects, as well as reducing costs.

[0003] With the continuous development of the construction industry, building formwork technology is also constantly improving. From traditional wooden formwork and bamboo formwork to modern steel formwork and plastic formwork, wooden formwork is made of wood and has the advantages of low cost and easy processing. However, wooden formwork has poor durability and is prone to warping, degumming, bulging, shelling, cracking, etc. after repeated use, requiring frequent replacement. The production of wooden formwork requires a large amount of wood, leading to excessive deforestation of forest resources, which is not conducive to environmental protection requirements. Although steel formwork has good strength and durability, it is heavy, making it difficult to transport and install. In addition, the material of the steel formwork itself may suffer surface damage in high temperature or humid environments, affecting the accuracy of the steel formwork. Plastic composite formwork solves the defects of wooden formwork and steel formwork, with the advantages of being light and fast, recyclable ring plates, low weight, and good mechanical strength. However, plastic building formwork still has some shortcomings. Since the base plastic itself is flammable, it lacks sufficient safety. Compared with steel formwork, the mechanical strength of plastic building formwork is still lower. Therefore, in usage scenarios with high load-bearing requirements, plastic formwork cannot replace steel formwork. Based on this, the present invention provides a composite green building formwork and a preparation method thereof. Summary of the Invention

[0004] The object of the present invention is to provide a composite green building template and a preparation method thereof, so as to solve the problems mentioned in the above background technology.

[0005] The purpose of the present invention can be achieved through the following technical solutions: A composite green building template comprises the following raw materials in parts by weight: 100 parts of polypropylene particles, 40-60 parts of glass fiber, 3-8 parts of silane coupling agent, 8-12 parts of talc powder, 16-20 parts of reinforcing agent, and 2-3 parts of antioxidant; A method for preparing a composite green building template comprises the following steps: The first step is to weigh the raw materials according to their mass: 100 parts of polypropylene particles, 40-60 parts of glass fiber, 3-8 parts of silane coupling agent, 8-12 parts of talc powder, 16-20 parts of reinforcing agent, and 2-3 parts of antioxidant; The second step is to grind the polypropylene particles and the reinforcing agent and pass them through a 300-mesh sieve, and then add the sieved mixed powder, glass fiber, silane coupling agent, talc powder, and antioxidant into a blender and stir and mix them evenly to obtain a prefabricated material; The third step is to add the prefabricated material into the mold, vacuum hot press sintering, and then cool to room temperature to obtain a composite green building template.

[0006] Furthermore, the glass fiber is alkali-free glass fiber.

[0007] Furthermore, the silane coupling agent is KH-550.

[0008] Furthermore, the specification of the talcum powder is 325 mesh.

[0009] Furthermore, the antioxidant is 1010 antioxidant.

[0010] Furthermore, in the second step, the mixing speed condition is 300-400 rpm, and the stirring and mixing time condition is 30-60 min.

[0011] Furthermore, the conditions for vacuum hot pressing sintering in the third step are: vacuum degree 0.004-0.01 MPa, sintering pressure 30-40 MPa, sintering temperature 220-240° C., and holding time 2 h.

[0012] Furthermore, the enhancer is prepared by the following steps: Step 1, 4-maleimidophenol, triethylamine, isopropanol, and sodium hydroxide solution are mixed in a three-necked flask, a condenser and a thermometer are installed, magnetic stirring is turned on, and the system temperature is raised to 70-75°C. Chloroform is then added dropwise to the three-necked flask, and the mixture is reacted at a temperature of 70-75°C for 4-6 hours. After the reaction is completed, the mixture is extracted with ethyl acetate, and the organic layer is separated with a separatory funnel. The organic layer is rotary evaporated to remove the solvent, and the remaining solid is recrystallized to obtain a cross-linking monomer; Step 2: Mix the cross-linking monomer, diphenylphosphine chloride, aluminum chloride, and N,N-dimethylformamide in a three-necked flask, install a condenser and a thermometer, turn on magnetic stirring, and react at a temperature of 75-80°C for 6-8h. After the reaction is completed, the solvent is removed by rotary evaporation, and the remaining solid is subjected to silica gel column chromatography to obtain the enhancer.

[0013] Preferably, the sodium hydroxide solution used in step 1 is a sodium hydroxide aqueous solution with a mass fraction of 30 to 40%.

[0014] Furthermore, the amount ratio of 4-maleimidophenol, triethylamine, isopropyl alcohol, sodium hydroxide solution and chloroform used in step 1 is 0.1 mol: 0.02-0.03 mol: 6-10 mL: 30-40 g: 22-26 mL.

[0015] Furthermore, the amount ratio of the cross-linking monomer, diphenylphosphine chloride, aluminum oxide, and N,N-dimethylformamide used in step 2 is 0.04 mol: 0.04 mol: 0.01-0.015 mol: 40-60 mL.

[0016] Beneficial effects of the present invention: The present invention uses polypropylene particles, glass fibers, silane coupling agents, talcum powder, reinforcing agents, and antioxidants as raw materials to prepare a composite green building template. The present invention comprises the following steps: firstly grinding and pulverizing the polypropylene particles and the reinforcing agent, then stirring and mixing the mixed powder with the glass fibers, silane coupling agents, talcum powder, and antioxidants to obtain a prefabricated material, and finally hot-pressing and sintering the prefabricated material to obtain the composite green building template. The preparation method of the present invention improves the impact resistance and tensile strength of the prepared building template by adding glass fibers to the polypropylene material, and also improves the shape stability of the building template.

[0017] The invention uses 4-maleimidophenol and chloroform as raw materials, adds isopropyl alcohol as a cosolvent, and undergoes a Reimer-Tierman reaction in an alkaline environment under triethylamine catalysis conditions to obtain a crosslinking monomer. The crosslinking monomer is then used as a raw material, and an esterification reaction is performed by utilizing the hydroxyl group of the crosslinking monomer and diphenylphosphinyl chloride to obtain a reinforcing agent. The reinforcing agent contains double bonds and aldehyde groups, can be copolymerized with polypropylene monomers to be combined in polymer molecular chains, and reacts with the amino group of a silane coupling agent to increase the crosslinking density of the material and the interfacial bonding strength between polypropylene and glass fiber, thereby improving the mechanical properties of the material. In addition, the phosphonate structure in the reinforcing agent can be decomposed at high temperature to form a heat-insulating and oxygen-isolating protective carbon layer, so that the prepared material has a flame-retardant effect and improves the safety performance of the material.

[0018] The composite green building template of the present invention uses polypropylene-glass fiber composite material, reduces the use of wood, is low-carbon and environmentally friendly, and the prepared building template has good impact resistance and tensile strength, is not easy to deform, and is flame retardant. DETAILED DESCRIPTION

[0019] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention. Example 1

[0020] A reinforcing agent is prepared by the following steps: Step 1, 0.1 mol 4-maleimidophenol, 0.02 mol triethylamine, 6 mL isopropanol, and 30 mL of a 40% mass fraction sodium hydroxide aqueous solution were mixed in a three-necked flask, a condenser and a thermometer were installed, magnetic stirring was turned on, and the system temperature was raised to 70°C. Then, 22 mL of chloroform was added dropwise to the three-necked flask, and the reaction was carried out at a temperature of 70°C for 4 hours. After the reaction was completed, the mixture was extracted with ethyl acetate, and the organic layer was separated with a separatory funnel. The organic layer was rotary evaporated to remove the solvent, and the remaining solid was recrystallized to obtain a cross-linking monomer; Step 2: 0.04 mol of cross-linking monomer, 0.04 mol of diphenylphosphinoyl chloride, 0.01 mol of aluminum chloride, and 40 mL of N,N-dimethylformamide were mixed in a three-necked flask, equipped with a condenser and a thermometer, and magnetic stirring was turned on. The mixture was reacted at a temperature of 75° C. for 6 h. After the reaction was completed, the solvent was removed by rotary evaporation, and the remaining solid was subjected to silica gel column chromatography to obtain the enhancer. Example 2

[0021] A reinforcing agent is prepared by the following steps: Step 1, 0.1 mol 4-maleimidophenol, 0.025 mol triethylamine, 8 mL isopropanol, and 35 mL of a 35% by mass sodium hydroxide aqueous solution were mixed in a three-necked flask, a condenser and a thermometer were installed, magnetic stirring was turned on, and the system temperature was raised to 72°C. Then, 24 mL of chloroform was added dropwise to the three-necked flask, and the reaction was carried out at a temperature of 72°C for 5 hours. After the reaction was completed, the mixture was extracted with ethyl acetate, and the organic layer was separated with a separatory funnel. The organic layer was rotary evaporated to remove the solvent, and the remaining solid was recrystallized to obtain a cross-linking monomer; Step 2: 0.04 mol of cross-linking monomer, 0.04 mol of diphenylphosphinoyl chloride, 0.012 mol of aluminum chloride, and 50 mL of N,N-dimethylformamide were mixed in a three-necked flask, equipped with a condenser and a thermometer, and magnetic stirring was turned on. The mixture was reacted at 77° C. for 7 h. After the reaction was completed, the solvent was removed by rotary evaporation, and the remaining solid was subjected to silica gel column chromatography to obtain the enhancer. Example 3

[0022] A reinforcing agent is prepared by the following steps: Step 1, 0.1 mol 4-maleimidophenol, 0.03 mol triethylamine, 10 mL isopropanol, and 40 mL of a 30% by mass sodium hydroxide aqueous solution were mixed in a three-necked flask, a condenser and a thermometer were installed, magnetic stirring was turned on, and the system temperature was raised to 75 ° C. Then, 26 mL of chloroform was added dropwise to the three-necked flask, and the reaction was carried out at a temperature of 75 ° C for 6 hours. After the reaction was completed, the mixture was extracted with ethyl acetate, and the organic layer was separated with a separatory funnel. The organic layer was rotary evaporated to remove the solvent, and the remaining solid was recrystallized to obtain a cross-linking monomer; Step 2: 0.04 mol of a cross-linking monomer, 0.04 mol of diphenylphosphinoyl chloride, 0.015 mol of aluminum chloride, and 60 mL of N,N-dimethylformamide were mixed in a three-necked flask, equipped with a condenser and a thermometer, and magnetic stirring was turned on. The mixture was reacted at 80° C. for 8 h. After the reaction was completed, the solvent was removed by rotary evaporation, and the remaining solid was subjected to silica gel column chromatography to obtain the enhancer. Example 4

[0023] A composite green building template comprises the following raw materials in parts by mass: 100 parts of polypropylene particles, 40 parts of alkali-free glass fiber, 3 parts of silane coupling agent KH-550, 8 parts of 325-mesh talc powder, 16 parts of the reinforcing agent obtained in Example 1, and 2 parts of 1010 antioxidant; A method for preparing a composite green building template comprises the following steps: The first step is to weigh the raw materials by mass: 100 parts of polypropylene particles, 40 parts of alkali-free glass fiber, 3 parts of silane coupling agent KH-550, 8 parts of 325 mesh talc, 16 parts of the reinforcing agent obtained in Example 1, and 2 parts of 1010 antioxidant; In the second step, the polypropylene particles and the reinforcing agent obtained in Example 1 were ground and passed through a 300-mesh sieve, and the sieved mixed powder, alkali-free glass fiber, silane coupling agent KH-550, 325-mesh talc, and 1010 antioxidant were added into a blender and stirred at a speed of 300 rpm for 30 minutes to obtain a prefabricated material; The third step is to add the prefabricated material into the mold, keep it warm for 2 hours under the conditions of vacuum degree 0.004MPa, sintering pressure 30MPa, and sintering temperature 220℃, and then cool it to room temperature to obtain a composite green building template. Example 5

[0024] A composite green building template comprises the following raw materials in parts by weight: 100 parts of polypropylene particles, 50 parts of alkali-free glass fiber, 6 parts of silane coupling agent KH-550, 10 parts of 325-mesh talc, 18 parts of the reinforcing agent obtained in Example 2, and 2.5 parts of 1010 antioxidant; A method for preparing a composite green building template comprises the following steps: The first step is to weigh the raw materials by mass: 100 parts of polypropylene particles, 50 parts of alkali-free glass fiber, 6 parts of silane coupling agent KH-550, 10 parts of 325 mesh talc, 18 parts of the reinforcing agent obtained in Example 2, and 2.5 parts of 1010 antioxidant; In the second step, the polypropylene particles and the reinforcing agent obtained in Example 2 were ground and passed through a 300-mesh sieve, and the sieved mixed powder, alkali-free glass fiber, silane coupling agent KH-550, 325-mesh talc, and 1010 antioxidant were added into a blender and stirred at a speed of 350 rpm for 45 minutes to obtain a prefabricated material; The third step is to add the prefabricated material into the mold, keep it warm for 2 hours under the conditions of vacuum degree 0.007MPa, sintering pressure 35MPa, and sintering temperature 230℃, and then cool it to room temperature to obtain a composite green building template. Example 6

[0025] A composite green building template comprises the following raw materials in parts by weight: 100 parts of polypropylene particles, 60 parts of alkali-free glass fiber, 8 parts of silane coupling agent KH-550, 12 parts of 325-mesh talc powder, 20 parts of the reinforcing agent obtained in Example 3, and 3 parts of 1010 antioxidant; A method for preparing a composite green building template comprises the following steps: The first step is to weigh the raw materials by mass: 100 parts of polypropylene particles, 60 parts of alkali-free glass fiber, 8 parts of silane coupling agent KH-550, 12 parts of 325 mesh talc, 20 parts of the reinforcing agent obtained in Example 3, and 3 parts of 1010 antioxidant; In the second step, the polypropylene particles and the reinforcing agent obtained in Example 3 were ground and passed through a 300-mesh sieve, and the sieved mixed powder, alkali-free glass fiber, silane coupling agent KH-550, 325-mesh talc, and 1010 antioxidant were added into a blender and stirred at a speed of 400 rpm for 60 minutes to obtain a prefabricated material; The third step is to add the prefabricated material into the mold, keep it warm for 2 hours under the conditions of vacuum degree 0.01MPa, sintering pressure 40MPa, and sintering temperature 240℃, and then cool it to room temperature to obtain a composite green building template.

[0026] Comparative Example 1 A composite green building template comprises the following raw materials in parts by mass: 100 parts of polypropylene particles, 60 parts of alkali-free glass fiber, 8 parts of silane coupling agent KH-550, 12 parts of 325 mesh talc powder, and 3 parts of 1010 antioxidant; A method for preparing a composite green building template comprises the following steps: The first step is to weigh the raw materials according to their mass: 100 parts of polypropylene particles, 60 parts of alkali-free glass fiber, 8 parts of silane coupling agent KH-550, 12 parts of 325 mesh talc powder, and 3 parts of 1010 antioxidant; The second step is to grind the polypropylene particles and pass them through a 300-mesh sieve, and add the sieved mixed powder, alkali-free glass fiber, silane coupling agent KH-550, 325-mesh talc, and 1010 antioxidant into a blender and stir at a speed of 400 rpm for 60 minutes to obtain a prefabricated material; The third step is to add the prefabricated material into the mold, keep it warm for 2 hours under the conditions of vacuum degree 0.01MPa, sintering pressure 40MPa, and sintering temperature 240℃, and then cool it to room temperature to obtain a composite green building template.

[0027] Comparative Example 2 A composite green building template comprises the following raw materials in parts by weight: 100 parts of polypropylene particles, 12 parts of 325-mesh talc powder, and 3 parts of 1010 antioxidant; A method for preparing a composite green building template comprises the following steps: The first step is to weigh the raw materials according to their mass fractions: 100 parts of polypropylene particles, 12 parts of 325 mesh talc powder, and 3 parts of 1010 antioxidant; The second step is to grind the polypropylene particles and pass them through a 300-mesh sieve, and then add the sieved mixed powder, 325-mesh talc powder, and 1010 antioxidant into a blender and stir at a speed of 400 rpm for 60 minutes to obtain a prefabricated material; The third step is to add the prefabricated material into the mold, keep it warm for 2 hours under the conditions of vacuum degree 0.01MPa, sintering pressure 40MPa, and sintering temperature 240℃, and then cool it to room temperature to obtain a composite green building template.

[0028] Comparative Example 3 This comparative example is a commercially available polypropylene building template.

[0029] Performance tests were performed on the composite green building templates of Examples 4 to 6 and Comparative Examples 1 to 2, and the commercially available polypropylene building template of Comparative Example 3. Impact resistance was tested in accordance with the national standard GB / T1843-2008 "Determination of Izod Impact Strength of Plastics," and tensile properties were tested in accordance with the national standard GB / T 1040.1-2006 "Determination of Tensile Properties of Plastics." Each group of building templates was cut into strips and then tested for vertical flame retardancy in accordance with the national standard GB / T2408-2021 "Determination of Combustion Properties of Plastics - Horizontal and Vertical Methods." The test results are shown in Table 1. Table 1 project <![CDATA[Impact strength / (KJ / m 2 )]]> Tensile properties / MPa Flame retardant grade Example 4 12.4 56.34 V-0 Example 5 13.6 58.29 V-0 Example 6 13.9 59.17 V-0 Comparative Example 1 11.2 47.56 V-2 Comparative Example 2 5.3 22.48 V-2 Comparative Example 3 10.4 45.72 V-1 As can be seen from Table 1, the mechanical properties and flame retardant properties of the composite green building formwork of the present invention in Examples 4 to 6 are better than those of the commercially available polypropylene building formwork. Comparative Examples 1 and 2 were used to conduct control experiments on the glass fiber and reinforcing agent added in the present invention. It can be seen that the addition of glass fiber can greatly improve the mechanical properties of the building formwork, and the addition of the reinforcing agent prepared by the present invention can further improve the mechanical properties of the polypropylene building formwork and give the building formwork good flame retardancy. In summary, the building formwork prepared by the present invention has excellent mechanical properties and good flame retardancy, and can be widely used in the construction field.

[0030] The above is a detailed introduction to a composite green building formwork and its preparation method provided by the present invention. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core ideas, including the best mode, and also enables any technician in this field to practice the present invention, including the manufacture and use of any device or system, and the implementation of any combination method. It should be pointed out that for ordinary technicians in this technical field, the present invention can also be improved and modified in a number of ways without departing from the principles of the present invention. In particular, as long as there is no structural conflict, the various features in the embodiments disclosed in the present invention can be combined with each other in any way. The reason why these combinations are not exhaustively described in this specification is simply for the sake of omitting space and saving resources. Therefore, the present invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A composite green building template, characterized in that: The invention comprises the following raw materials in parts by weight: 100 parts of polypropylene particles, 40-60 parts of glass fiber, 3-8 parts of silane coupling agent, 8-12 parts of talc powder, 16-20 parts of reinforcing agent, and 2-3 parts of antioxidant; Wherein, the reinforcing agent is prepared by the following steps: 4-Maleimidophenol, triethylamine, isopropyl alcohol, and sodium hydroxide solution are mixed and the system temperature is raised to 70-75°C. Chloroform is then added to the system and the system temperature is controlled at 70-75°C for reaction to obtain a crosslinking monomer. The crosslinking monomer, diphenylphosphine chloride, aluminum chloride, and N,N-dimethylformamide are then mixed and the system temperature is controlled at 75-80°C for reaction to obtain an enhancer.

2. A composite green building template according to claim 1, characterized in that: The sodium hydroxide solution used in step 1 is a sodium hydroxide aqueous solution with a mass fraction of 30 to 40%.

3. A composite green building template according to claim 1, characterized in that: The amount ratio of 4-maleimidophenol, triethylamine, isopropyl alcohol, sodium hydroxide solution and chloroform used in step 1 is 0.1 mol: 0.02-0.03 mol: 6-10 mL: 30-40 g: 22-26 mL.

4. A composite green building template according to claim 1, characterized in that: The amount ratio of the cross-linking monomer, diphenylphosphine chloride, aluminum oxide, and N,N-dimethylformamide used in step 2 is 0.04 mol: 0.04 mol: 0.01-0.015 mol: 40-60 mL.

5. A method for preparing a composite green building template according to any one of claims 1 to 4, characterized in that: The method comprises the following preparation steps: The polypropylene and the reinforcing agent are ground and passed through a 300-mesh sieve, and the sieved mixed powder is stirred and mixed with glass fiber, silane coupling agent, talcum powder, and antioxidant, and then added into a mold. After vacuum hot pressing and sintering, the composite green building template is cooled to room temperature to obtain the composite green building template.

6. The method for preparing a composite green building template according to claim 5, characterized in that: The glass fiber is alkali-free glass fiber, and the silane coupling agent is KH-550.

7. The method for preparing a composite green building template according to claim 5, characterized in that: The specification of the talcum powder is 325 mesh.

8. The method for preparing a composite green building template according to claim 5, characterized in that: The antioxidant is 1010 antioxidant.

9. The method for preparing a composite green building template according to claim 5, characterized in that: In the second step, the mixing speed condition is 300-400 rpm, and the stirring and mixing time condition is 30-60 min.

10. The method for preparing a composite green building template according to claim 5, characterized in that: The conditions for vacuum hot pressing sintering in the third step are: vacuum degree 0.004-0.01 MPa, sintering pressure 30-40 MPa, sintering temperature 220-240° C., and holding time 2 h.