A thermosetting composite polystyrene foam insulation board with a pore blocking structure and a preparation method thereof

Abstract

The present application relates to the technical field of building insulation materials, and discloses a thermosetting composite polystyrene foam insulation board with a pore blocking structure and a preparation method thereof. The thermosetting composite polystyrene foam insulation board with the pore blocking structure comprises a porous board substrate formed by a cement-based gelling material and EPS particles, and a blocking structure formed by expanded microspheres is arranged in at least partially connected pores in the board substrate, so as to reduce the gas flowability and heat transfer in the board. The preparation method comprises the following steps: introducing a treatment liquid containing expandable microspheres into the pores in the thermosetting composite polystyrene foam insulation board, so that the unexpanded expandable microspheres are at least partially retained in the pores in the board; then, the board is subjected to a heating treatment, so that the expandable microspheres are volumetrically expanded in the pores in the board, thereby forming the blocking structure; finally, the board is subjected to a drying treatment. According to the present application, the connected pores in the board are blocked by post-treatment, the continuous air heat transfer path formed by the connected pores in the board is weakened, and the heat conductivity of the board is reduced. In the premise of not significantly increasing the density of the board and not substantially reducing the mechanical properties, the heat insulation performance of the thermosetting composite polystyrene foam insulation board is improved.

Description

Technical Field

[0001] This invention relates to the field of building insulation materials technology, specifically to a thermosetting composite polystyrene foam insulation board that reduces thermal conductivity by forming an expanded microsphere blocking structure in the internal pores of the board, and its preparation method. Background Technology

[0002] Thermosetting composite polystyrene foam insulation board is a type of composite insulation material formed with cement-based cementitious materials as the continuous phase and EPS particles as lightweight aggregate. This type of material has certain fire resistance, thermal insulation performance, dimensional stability and mechanical properties, and has been widely used in building exterior wall insulation, fire barriers and prefabricated buildings in recent years.

[0003] Existing thermosetting composite polystyrene foam insulation boards are typically produced by mixing EPS particles with cement slurry and then pressing them into shape. Due to the packing structure between EPS particles and the coating characteristics of the cement slurry, the board usually contains a large number of interconnected millimeter-sized irregular pores and gas channels. Air easily forms continuous heat transfer paths within these interconnected channels, thereby enhancing the internal heat transfer effect of the board and making it difficult to form a stable closed insulation structure inside the board.

[0004] Therefore, there is a significant bottleneck in reducing the thermal conductivity of existing thermosetting composite polystyrene foam insulation boards. According to the industry standard JG / T 536-2017, the thermal conductivity of 050 grade boards must be below 0.050 W / (m·K), and the compressive strength must be no less than 0.15 MPa. However, due to the inherent structural characteristics of thermosetting composite polystyrene foam insulation boards, achieving these specifications is quite challenging.

[0005] Currently, the industry typically reduces the thermal conductivity of boards by adding low-thermal-conductivity lightweight fillers such as aerogel to the cement slurry system. However, this approach usually leads to a significant decrease in mechanical properties and a significant increase in cost, limiting its widespread application.

[0006] Existing technologies mostly focus on adjusting the material composition, while relatively little attention is paid to the treatment of the internal interconnecting channels of the sheet material itself. In particular, there is a lack of a method that can post-process and seal the internal interconnecting pores of the sheet material without significantly increasing the sheet density and with minimal reduction in mechanical properties, thereby reducing the thermal conductivity. Summary of the Invention

[0007] (a) Purpose of the invention The purpose of this invention is to provide a thermosetting composite polystyrene foam insulation board with a pore-blocking structure and its preparation method. By forming an expanded microsphere blocking structure in the pores inside the board, the continuous gas heat transfer path formed by the interconnected channels inside the board is weakened, thereby reducing the thermal conductivity of the board.

[0008] Meanwhile, the present invention also provides a method for preparing a thermosetting composite polystyrene foam insulation board with a pore-blocking structure.

[0009] (II) Technical Solution 1. A thermosetting composite polystyrene foam insulation board with a pore-blocking structure A thermosetting composite polystyrene foam insulation board with a pore-blocking structure includes a porous board matrix formed by cement-based cementitious materials and EPS particles. The board matrix is ​​characterized in that at least some of the interconnected pores inside the board matrix are provided with a blocking structure formed by expanded microspheres to reduce the gas flow and heat transfer inside the board.

[0010] Preferably: (1) The expandable microspheres are microspheres that can expand in volume when heated, and should be hydrophilic low-temperature expandable type; (2) The expanded microspheres form a locally closed-cell barrier structure inside the pores of the insulation board; (3) The blocking structure is distributed at the narrowing of the channel, the wall of the channel, or the pore node.

[0011] 2. A method for preparing a thermosetting composite polystyrene foam insulation board with a pore-blocking structure. A method for preparing a thermosetting composite polystyrene foam insulation board with a pore-blocking structure includes the following steps: Step 1: Preparation of a liquid system containing expandable microspheres Expandable microspheres are added to a liquid medium, along with a viscosity modifier that can improve the system's viscosity, suspension stability, or adhesion, to form a treatment solution.

[0012] Step 2: Pore permeation treatment The treatment liquid is introduced into the internal pores of the thermosetting composite polystyrene foam insulation board by a permeation method, so that the treatment liquid can enter at least some of the interconnected pores inside the board.

[0013] During this process, expandable microspheres enter the internal pores of the board along with the treatment liquid and remain at least partially inside the pores.

[0014] Step 3: Heating and expansion treatment The permeation-treated board is heated, causing the expanded microspheres to expand in volume within the pores of the board, thereby forming a blockage structure.

[0015] Step 4: Drying treatment The boards are dried to remove residual moisture and stabilize the board structure.

[0016] (III) Beneficial Effects Compared with the prior art, the present invention has the following advantages: 1. Reduce the heat transfer path of continuous gas. By forming an in-situ expansion and blocking structure inside the plate, the continuous gas heat transfer path formed by the connecting channels is weakened, thereby reducing the heat transfer effect inside the plate.

[0017] 2. Reduce thermal conductivity The thermal conductivity of the microsphere aggregates formed after the expandable microspheres expand when heated is usually significantly lower than that of the thermosetting composite polystyrene foam insulation board matrix, which can further reduce the overall thermal conductivity of the insulation board.

[0018] 3. Minimal impact on bulk density Since expandable microspheres can expand tens of times in volume when heated, and their density is generally 15-25 kg / m³, the amount of expandable microspheres required to fill the pores inside the insulation board is small and will not significantly increase the density of the insulation board.

[0019] 4. Minimal impact on mechanical properties Since the expandable microspheres are mainly distributed in the pores inside the board, and the aggregate strength of the expanded microspheres is low, they will not significantly damage the original cement skeleton structure of the board and have little impact on the mechanical properties of the insulation board.

[0020] 5. Suitable for continuous production It is suitable for continuous permeation and continuous heating processes and has the potential for continuous production. Attached Figure Description

[0021] Figure 1 Existing cross-sectional view of thermosetting composite polystyrene foam insulation board; Figure 2 Cross-sectional view of thermosetting composite polystyrene foam insulation board with pore-blocking structure; Detailed Implementation

[0022] The present invention will be further described below with reference to the embodiments, but the scope of protection of the present invention is not limited to the following embodiments.

[0023] Any equivalent substitutions, modifications, improvements, or combinations made by those skilled in the art to this invention without departing from the technical concept of this invention shall fall within the protection scope of this invention.

[0024] The parts not described in detail in this invention can all be implemented using conventional techniques in the field.

[0025] Example 1 A method for preparing a thermosetting composite polystyrene foam insulation board with a pore-blocking structure specifically includes the following steps: (1) Preparation of treatment solution Prepare a treatment solution containing expanded microspheres: The mass percentage of microsphere foaming powder is 1.5~2.5%, and 0~0.5% HPMC and 0.5~1.0% PVA are added and stirred to form a uniform treatment solution.

[0026] in: The microsphere foaming powder used is Dongjin Cell-ms140ws or similar hydrophilic low-temperature expandable microspheres; The amount of HPMC and PVA added can be adjusted according to the viscosity requirements of the treatment solution to ensure that the treatment solution has a viscosity that allows the expanded microspheres to remain suspended stably and improves their retention capacity inside the pores.

[0027] (2) Infiltration treatment of boards Place the thermosetting composite polystyrene foam insulation board on the negative pressure support platform and connect a vacuum pump to the underside of the board.

[0028] Subsequently, the treatment liquid is applied to the upper surface of the board. Under the action of pressure difference, the treatment liquid penetrates the board from top to bottom along the internal interconnected pores.

[0029] During the infiltration process, some of the unexpanded microspheres enter the pores inside the board and remain on the pore walls, at the narrowing of the pores, and in the pore node areas.

[0030] (3) Tunnel microwave expansion treatment The permeation-treated boards are then fed into a tunnel-type microwave heating device for continuous heating treatment.

[0031] By controlling the track speed and microwave output power, the internal temperature of the plate material reaches 85-90°C when it leaves the microwave area. The unexpanded microspheres expand in volume when heated and form a blocking structure in the pores inside the plate material.

[0032] The microwave heating is mainly used to trigger the expansion of the microspheres, rather than to complete the overall drying of the board.

[0033] (4) Drying treatment After the microwave expansion treatment is completed, the board is dried to remove residual moisture and stabilize the board structure.

[0034] The drying methods are natural air drying, hot air drying, or low-temperature drying.

[0035] (5) Examples of the properties of the obtained sheet material Under the conditions of this embodiment, after treating the thermosetting composite polystyrene foam insulation board, the thermal conductivity can be reduced and the density change can be minimized.

[0036] The initial performance indicators of the thermosetting composite polystyrene foam insulation board used in this embodiment are: thermal conductivity 0.052W / (m·K), compressive strength 0.20MPa, and oven-dry density 126kg / m³.

[0037] After processing by the method of this embodiment, the performance indicators of the thermosetting composite polystyrene foam insulation board with pore blockage structure are as follows: thermal conductivity 0.046 W / (m·K), compressive strength 0.19 MPa, and oven-dry density 127 kg / m³.

[0038] The performance data described above are typical test results obtained under specific process conditions in this embodiment and should not be construed as limiting the treatment effect of the present invention. The actual treatment effect may vary depending on the plate structure, porosity, type of expandable microspheres, composition of the treatment solution, and process conditions.

Claims

1. A thermosetting composite polystyrene foam insulation board with a pore-blocking structure, comprising a porous board matrix formed of cementitious material and EPS particles, characterized in that: The substrate contains at least some interconnected pores with a blocking structure formed by expandable microspheres.

2. The thermosetting composite polystyrene foam insulation board according to claim 1, characterized in that: The expandable microspheres are microspheres that can expand in volume when heated.

3. The thermosetting composite polystyrene foam insulation board according to claim 1, characterized in that: The blocking structures are distributed at the narrowing of the duct, at the duct wall, or at the pore nodes.

4. A method for preparing a thermosetting composite polystyrene foam insulation board with a pore-blocking structure as described in any one of claims 1 to 3, characterized in that, Includes the following steps: (1) Prepare a treatment solution containing expandable microspheres; (2) The treatment liquid is introduced into the internal pores of the thermosetting composite polystyrene foam insulation board, so that the expandable microspheres are at least partially retained in the internal pores of the board. (3) The plate is heated to cause the expandable microspheres to expand in volume, thereby forming a blocking structure in the pores inside the plate; (4) Dry the board.

5. The preparation method according to claim 4, characterized in that: The treatment solution contains a viscosity modifier that can improve the viscosity, suspension stability, or adhesion of the system.

6. The preparation method according to claim 4, characterized in that: The treatment solution is introduced into the internal pores of the board through pressure differential penetration, immersion penetration, or capillary penetration.

7. The preparation method according to claim 4, characterized in that: The heating process employs one or more of microwave heating, hot air heating, or infrared heating.

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