Process for producing a glass fiber fireproof thermal insulation core

Abstract

The application discloses a production process method of a glass fiber fireproof thermal insulation core material, belongs to the technical field of glass fiber processing, and utilizes ethylene glycol aqueous short-cut fibers, short-cut glass fibers and sodium silicate powder to uniformly mix to prepare a fiber glue mixture. The polyvinyl alcohol short-cut fibers are firstly mixed with the polyvinyl alcohol aqueous short-cut fibers and the short-cut glass fibers and the solid sodium silicate powder as a soluble template, are uniformly coated between the glass fiber mats in the interval layer, are bonded through hot pressing, and then the polyvinyl alcohol is removed after the polyvinyl alcohol hot water is heated, the polyvinyl alcohol is removed, the gap is formed, the device cost is low, the operation is simple, the production process is simple and environment-friendly, the human body is not harmed, the fireproof and flame-retardant performance is excellent, the thermal conductivity and the flame retardance are excellent, the vacuum glass fiber thermal insulation plate can be prepared by using the core material, the use of foamed plastic is reduced, the glass fiber fireproof thermal insulation core material is free of resin and other polymers, and energy consumption is reduced.

Description

Technical Field

[0001] This invention belongs to the field of glass fiber processing technology, specifically relating to a production process method for glass fiber fireproof and heat-insulating core material. Background Technology

[0002] Vacuum insulation panels are a type of high-efficiency insulation material made by filling a load-bearing core material into an aluminum-plastic composite gas barrier bag and then vacuum sealing it. To maintain a good vacuum environment inside the panel, a getter can also be added. The heat transfer of the internal gas is eliminated by vacuuming, thus reducing its thermal conductivity. Chinese patent CN106630651A discloses a type of glass fiber used to manufacture the core material of vacuum insulation panels, which reduces the content of CaO, MgO, B2O3, and Al. 2O3The content of oxides did not significantly affect the thermal conductivity of the core material, and no specific preparation method for the fireproof and heat-insulating core material was provided. Vacuum insulation panels use vacuum insulation materials and consist of three parts: a porous media material as the core material, a vacuum sealing membrane to ensure the vacuum level inside the panel, and a getter or desiccant to absorb various gases that permeate the membrane and enter the panel. In previous technologies, glass fiber core materials were manufactured using centrifugal blowing technology and prepared using wet forming technology. For example, (Xu TZ, Chen ZF, Zhou JM, et al. Ultrafine glass fiber core material produced by wet method[C] / / Advanced Materials Research. Trans Tech Publications Ltd,2012, 430: 1343-1347.). The cost of core material manufacturing accounts for more than 45% of the price of vacuum insulation panels, so the price of core material raw materials and manufacturing costs are key factors determining its widespread application. Currently, fumed silica is mainly used as the core material abroad, but its high price hinders its practical application in my country. Domestically, wet-process glass fiber is the main material, but its production process is complex and environmentally unfriendly, the product is not easily degradable, and it can easily cause harm to the human body, limiting the widespread use of VIP in the insulation field. Furthermore, Chinese patent CN201710609831.2 discloses a glass fiber core material coated with high-strength continuous carbon fibers, with the glass fiber conductors bonded together into a single cable conductor using cured high-temperature resistant epoxy resin. This core material is not used for insulation boards, but the bonding effect of polymer resin is also unsuitable for use in glass fiber insulation boards because the resin is not flame-retardant and will produce a large amount of toxic and harmful gases when burned. Chinese patent CN103274603A discloses a novel glass fiber, a vacuum insulation panel core material based on this glass fiber, and a preparation method thereof. This method employs a dry process, where molten glass is introduced into a centrifuge and rotated at high speed, causing the molten glass to be ejected from small holes in the centrifuge sidewall, forming fine glass streams. This process fiberizes the molten glass and limits the composition content of the glass fibers. However, the aforementioned dry and wet processes, including improvements to the glass fiber composition in CN106630651A and CN103274603A, are complex and require expensive equipment, failing to meet the objective requirements of raw material price and production cost for core materials. There is an urgent need in those skilled in the art to develop a production process for glass fiber fireproof and heat-insulating core materials to meet current application market and performance requirements. Summary of the Invention

[0003] In view of this, the present invention provides a production process for a glass fiber fireproof and heat-insulating core material.

[0004] A manufacturing process for a glass fiber fireproof and heat-insulating core material includes the following steps:

[0005] Step 1: After uniformly coating the needle-punched glass fiber mat with a fiber adhesive mixture, hot-pressing the adhesive, and then fixing it with a wire mesh clamp, a chopped needle-punched glass fiber mat board is obtained. The fiber adhesive mixture comprises a uniform mixture of polyvinyl alcohol water-soluble chopped fibers, chopped glass fibers, and solid sodium silicate powder. The coating amount of the fiber adhesive mixture is 420–450 g / m². 2 Step 2, Aging and Gel Coagulation: The short-cut needle-punched glass fiber mat obtained in Step 1 is placed in a drying room with a relative humidity of 70%, a temperature of 50°C, and a carbon dioxide content of 4% for 10 hours, or aged in air at room temperature and relative humidity of 60% for 15 days, or evenly blown onto the surface of the short-cut needle-punched glass fiber mat at 45°C, a carbon dioxide pressure of 0.6 MPa, and a blowing pressure of 0.35 MPa, one side at a time, for 100 seconds. Step 3, Adhesive Removal: The aged and gelled short-cut needle-punched glass fiber mat, which is fixed between wire mesh clamps, is immersed in hot water at 95-100°C for 1-2 hours to remove polyvinyl alcohol. After removing the polyvinyl alcohol, the wire mesh clamps are opened, and the mat is air-dried at room temperature to obtain the final product.

[0006] Fiberglass insulation board core material is a plate-shaped material made of fiberglass used inside vacuum insulation boards, which has a certain supporting and heat preservation function.

[0007] Core material is the material placed inside the insulation film bag of the heat insulation board, which plays a role in preventing the board from collapsing and reducing heat radiation.

[0008] Fiberglass mat is a felt-like sheet made of medium-grade fixed-length fiberglass. In the past, it was mainly used in conjunction with emulsified asphalt or petroleum asphalt coatings for building waterproofing projects.

[0009] The preferred unit area mass of fiberglass mat is 250–600 g / m². 2 For example, the mass per unit area is 450g / m². 2 Alkali-free glass chopped strand mat EMC450-1600 with a width of 1600mm.

[0010] Furthermore, the fiber adhesive mixture in the first step may also include ferrosilicon powder, the mass of which is 3% to 5% of the mass of solid sodium silicate.

[0011] Furthermore, the first step of uniformly coating the fiber adhesive mixture and then hot-pressing it specifically involves: evenly spreading a layer of fiber adhesive mixture on the surface of the needle-punched glass fiber mat using a scraper; spreading a roll of un-adhesive needle-punched glass fiber mat onto the surface of the needle-punched glass fiber mat to be adhesiveized; rolling it radially while spreading; applying another layer of fiber adhesive mixture; and repeating the above operation 2 to 4 times using a scraper and roller to obtain a composite assembly containing 3 to 5 layers of needle-punched glass fiber mat; and then hot-pressing it at 220 to 230°C and 0.3 to 0.4 MPa for 2 to 4 minutes.

[0012] Furthermore, the fiber adhesive mixture in the first step, by weight, comprises 13-15 parts of polyvinyl alcohol water-soluble chopped fibers, 45-50 parts of chopped glass fibers, and 13-17 parts of sodium silicate powder.

[0013] Furthermore, the polyvinyl alcohol water-soluble chopped fiber is a 1.56 dtex × 38 mm polyvinyl alcohol water-soluble chopped fiber with a melting point of 76–95 °C.

[0014] Polyvinyl alcohol (PVA) water-soluble short fibers, after treatment, dissolve in water under certain temperature conditions, achieving the effect of debinding. Simultaneously, PVA can be concentrated, recycled, and reused, and the hot water can also be reused.

[0015] Polyvinyl alcohol water-soluble short fibers can be completely dissolved in sufficient water at a certain temperature.

[0016] Furthermore, the chopped glass fibers have a length of 3–24 mm and a diameter of 10–14 μm.

[0017] Furthermore, the modulus of the sodium silicate powder is 3.1 to 3.4.

[0018] The beneficial effects of this invention are:

[0019] This invention utilizes a uniform mixture of polyvinyl alcohol (PVA) water-soluble chopped fibers, chopped glass fibers, and solid sodium silicate powder to create a fiber adhesive mixture. The PVA chopped fibers first act as a soluble template, uniformly mixing with the chopped glass fibers and solid sodium silicate powder. This mixture is then uniformly applied between interlayered glass fiber mats and bonded together by hot pressing, forming a chopped needle-punched glass fiber mat adhesive board. By controlling appropriate temperature and process, the PVA fibers do not undergo significant deformation, allowing the core material to be initially bonded and formed. Subsequently, through an aging gelation reaction, the solid sodium silicate fully reacts and gels with the chopped glass fibers and glass fiber mat, forming a chemical bond between the glass fiber mat and the chopped glass fibers, resulting in a multi-angled, multi-layered structure. At this stage, the chopped needle-punched glass fiber mat adhesive board exhibits both inorganic and organic bonding properties. Finally, by heating the PVA in hot water to remove the adhesive and create voids, the PVA is removed, yielding the glass fiber fireproof and heat-insulating core material.

[0020] The present invention has the following advantages over the prior art:

[0021] The production process of the glass fiber fireproof and heat-insulating core material disclosed in this invention has fewer production steps and advantages such as low equipment cost and simple operation compared with the existing dry or wet processes. However, its production process is simple and environmentally friendly, and will not cause harm to the human body. It has excellent fireproof and flame-retardant properties, and has superior thermal conductivity and flame retardancy. Using this core material, vacuum glass fiber insulation boards can be prepared. The heat insulation performance is more than 10 times that of traditional polyurethane foam. It has the characteristics of low weight and good high-temperature stability. It has a layered structure with fibers arranged at multiple angles, reducing the use of foamed plastics. In fact, the glass fiber fireproof and heat-insulating core material does not contain resin or other polymers, reducing energy consumption and making it green and environmentally friendly. It poses no harm to the human body during production and use. Implementation

[0022] Example

[0023] Raw materials prepared: Polyvinyl alcohol water-soluble chopped strand fiber (Ningxia Dadi Circulation SW-9 qualified product, 1.56 dtex × 38 mm), Bengbu Longquan silicon material LQ900 sodium silicate powder (modulus 3.4), Kunxinda ferrosilicon powder (particle size 1 mm, Si+Fe ≥ 95%, Al ≤ 2%, C ≤ 0.5%, P ≤ 0.04%, S ≤ 0.03%, Si ≥ 72%). The chopped glass fiber is WJ1001-103 fiber produced by Weijia Composite Materials Co., Ltd., with a nominal diameter of 10 μm, a chopped length of 18 mm, a longitudinal breaking strength of 120 N / 150 mm, and a transverse breaking strength of 120 N / 150 mm, and is EMC-450 alkali-free chopped glass fiber mat.

[0024] Production process for preparing glass fiber fireproof and heat-insulating core material using the above raw materials:

[0025] Step 1: After uniformly coating the needle-punched fiberglass mat with a fiber adhesive mixture and then hot-pressing it, the following steps are taken: A layer of fiber adhesive mixture is evenly spread on the surface of the needle-punched fiberglass mat using a scraper. A roll of un-adhesive needle-punched fiberglass mat is then laid onto the surface of the mat to be adhesiveized, and while spreading, it is rolled radially with a roller. Another layer of fiber adhesive mixture is then applied. This process is repeated twice using a scraper and roller to obtain a composite assembly containing three layers of needle-punched fiberglass mat. This assembly is then placed at 230℃. Hot-pressed at 0.4 MPa for 4 minutes, and fixed with a wire mesh clamp, a short-cut needle-punched glass fiber mat board is obtained. The mixture comprises 15 parts of polyvinyl alcohol water-soluble short-cut fibers, 50 parts of short-cut glass fibers, and 17 parts of sodium silicate powder. The fiber adhesive mixture may also include ferrosilicon powder, the mass of which is 5% of the mass of solid sodium silicate. The polyvinyl alcohol water-soluble short-cut fibers, short-cut glass fibers, solid sodium silicate powder, and ferrosilicon powder are uniformly mixed to form the fiber adhesive mixture. The coating amount of the fiber adhesive mixture is 450 g / m². 2 The second step, aging and gelling: The short-cut needle-punched glass fiber mat obtained in the first step is placed in a drying room with a relative humidity of 70%, a temperature of 50°C, and a carbon dioxide content of 4% for 10 hours to complete the process. The third step, glue removal: The aged and gelled short-cut needle-punched glass fiber mat, which is fixed between wire mesh clamps, is immersed in hot water at 100°C and heated for 2 hours to remove polyvinyl alcohol. After removing the polyvinyl alcohol, the wire mesh clamps are opened, and the mat is air-dried at room temperature to obtain the final product.

[0026] Product appearance: The core material surface is white, uniform, flat, and free of impurities, including hard objects such as glass fibers and rods.

[0027] Product performance: Thermal conductivity at 25℃ is 0.033W / (m·K), moisture content is 0.45%, slag ball content is 0.32%, combustion performance is A2 grade, compressive strength is 1.2MPa, and surface density is 4.6kg / ㎡.

[0028] Example

[0029] Raw materials prepared: 1.56 dtex × 38 mm water-soluble chopped polyvinyl alcohol (PVA) fiber (Chongqing Rongzhiwei RS-9F qualified product), 3.1% sodium silicate (Huaibei Rongzhu New Materials Co., Ltd.). The chopped glass fiber is WJ1001-101 fiber produced by Weijia Composite Materials Co., Ltd., with a nominal diameter of 10 μm, a chopped length of 4.5 mm, a longitudinal breaking strength of 40 N / 150 mm, and a transverse breaking strength of 40 N / 150 mm, as well as EMC-250 alkali-free chopped glass fiber mat.

[0030] Production process for preparing glass fiber fireproof and heat-insulating core material using the above raw materials:

[0031] Step 1: After uniformly coating the needle-punched glass fiber mat with a fiber adhesive mixture and then hot-pressing it, the following steps are taken: A layer of fiber adhesive mixture is evenly spread on the surface of the needle-punched glass fiber mat using a scraper. A roll of un-adhesive needle-punched glass fiber mat is then laid onto the surface of the mat to be coated. While spreading, it is rolled and pressed radially with a roller. Another layer of fiber adhesive mixture is then applied. This process is repeated four times using a scraper and roller to obtain a composite assembly containing five layers of needle-punched glass fiber mat. This assembly is then hot-pressed at 220℃ and 0.3MPa for 2 minutes and fixed with a wire mesh clamp to obtain a chopped needle-punched glass fiber mat adhesive sheet. The adhesive mixture consists of 13 parts of polyvinyl alcohol water-soluble chopped fiber, 45 parts of chopped glass fiber, and 13 parts of sodium silicate powder. The fiber adhesive mixture is a uniform mixture of polyvinyl alcohol water-soluble chopped fiber, chopped glass fiber, and solid sodium silicate powder. The coating amount of the fiber adhesive mixture is 420g / m². 2 Step 2, Aging and gelling: The short-cut needle-punched glass fiber mat obtained in Step 1 is aged in air at room temperature and relative humidity of 50% for 10 days. Step 3, De-gelling: The aged and gelled short-cut needle-punched glass fiber mat, which is fixed between wire mesh clamps, is immersed in hot water at 95°C and heated for 1 hour to remove polyvinyl alcohol. After removing the polyvinyl alcohol, the wire mesh clamps are opened, and the mat is air-dried at room temperature to obtain the final product.

[0032] Product appearance: The core material surface is white, uniform, flat, and free of impurities, including hard objects such as glass fibers and rods.

[0033] Product performance: Thermal conductivity at 25℃ is 0.031W / (m·K), moisture content is 0.43%, slag ball content is 0.33%, combustion performance is A2 grade, compressive strength is 1.1MPa, and surface density is 4.0kg / ㎡.

[0034] Example

[0035] The raw materials used are: 1.56 dtex × 38 mm polyvinyl alcohol water-soluble chopped strands (Wanwei S-8 qualified product), sodium silicate (Huaibei Rongzhu New Materials Co., Ltd.); 1.56 dtex × 38 mm Chongqing Rongzhiwei RS-9F qualified product, 3.4 g sodium silicate (Huaibei Rongzhu New Materials Co., Ltd.); and WJ1001-103 fiber (Nominal diameter 14 μm, average chopped length 30 mm) produced by Weijia Composite Materials Co., Ltd., Yongqiao Qidong Gas - Industrial Carbon Dioxide, EMC-600 alkali-free glass fiber chopped strand mat with longitudinal tensile strength 150 N / 150 mm and transverse tensile strength 150 N / 150 mm.

[0036] Production process for preparing glass fiber fireproof and heat-insulating core material using the above raw materials:

[0037] Step 1: After uniformly coating the needle-punched glass fiber mat with a fiber adhesive mixture and then hot-pressing it, the following steps are taken: A layer of fiber adhesive mixture is evenly spread on the surface of the needle-punched glass fiber mat using a scraper. A roll of un-adhesive needle-punched glass fiber mat is then laid onto the surface of the mat to be adhesiveized. While spreading, it is rolled and pressed radially with a roller. Another layer of fiber adhesive mixture is then applied. This process is repeated 6 times using a scraper and roller to obtain a composite assembly containing 5 layers of needle-punched glass fiber mat. This assembly is then hot-pressed at 230℃ and 0.35MPa for 3 minutes and fixed with a wire mesh clamp to obtain a chopped needle-punched glass fiber mat adhesive sheet. The adhesive mixture consists of 14 parts of polyvinyl alcohol water-soluble chopped fiber, 47 parts of chopped glass fiber, and 15 parts of sodium silicate powder. The fiber adhesive mixture is a uniform mixture of polyvinyl alcohol water-soluble chopped fiber, chopped glass fiber, and solid sodium silicate powder. The coating amount of the fiber adhesive mixture is 450g / m². 2 Step 2, Aging and gelling: The short-cut needle-punched glass fiber mat obtained in Step 1 is subjected to uniform blowing of carbon dioxide gas at 45℃ and a pressure of 0.6MPa and a blowing pressure of 0.35MPa on both sides of the short-cut needle-punched glass fiber mat surface, with each side being blown for 100s. Step 3, Adhesive removal: The aged and gelled short-cut needle-punched glass fiber mat surface, which is fixed between the wire mesh clamps, is immersed in hot water at 100℃ and heated for 2 hours to remove polyvinyl alcohol. After removing the polyvinyl alcohol, the wire mesh clamps are opened, and the mat is air-dried at room temperature to obtain the final product.

[0038] Product appearance: The core material surface is white, uniform, flat, and free of impurities, including hard objects such as glass fibers and rods.

[0039] Product performance: Thermal conductivity at 25℃ is 0.031W / (m·K), moisture content is 0.41%, slag ball content is 0.35%, combustion performance is A2 grade, compressive strength is 1.4MPa, and surface density is 5.1kg / ㎡.

[0040] Note: The reference thermal conductivity is based on the provisions of GB / T 10295-2008 Determination of Steady-State Thermal Resistance and Related Properties of Insulation Materials by Heat Flow Meter Method. The slag ball content is based on the provisions of JC / T 978-2012 Microfiber Glass Wool. The areal density is determined according to GB / T9914.3-2013 Test Methods for Reinforced Products Part 3: Determination of Mass per Unit Area. The combustion performance is judged according to the provisions of GB8624 Classification of Combustion Performance of Building Materials and Products. Three test specimens of 40mm×40mm×40mm nanoporous insulation board are prepared and tested according to GB / T 5486-2008. The three layers of nanoporous insulation board are stacked with a thickness compression of 20%, referring to the test methods of GB / T5486-2008 Inorganic Rigid Insulation Products.

[0041] In summary, it can be seen that the production process of the glass fiber fireproof and heat-insulating core material disclosed in this invention has low cost, is easy to operate, and has a very good market application prospect.

Claims

1. A production process for a glass fiber fireproof and heat-insulating core material, characterized in that, Includes the following steps: Step 1: After uniformly coating the needle-punched glass fiber mat with a fiber adhesive mixture, hot-pressing the adhesive, and then fixing it with a wire mesh clamp, a chopped needle-punched glass fiber mat board is obtained. The fiber adhesive mixture comprises a uniform mixture of polyvinyl alcohol water-soluble chopped fibers, chopped glass fibers, and solid sodium silicate powder. The coating amount of the fiber adhesive mixture is 420–450 g / m². 2 ; The process of uniformly coating the fiber adhesive mixture and then hot-pressing it involves: spreading a layer of fiber adhesive mixture evenly on the surface of the needle-punched glass fiber mat using a scraper; spreading an uncoated roll of needle-punched glass fiber mat onto the surface of the needle-punched glass fiber mat to be coated; rolling it with a roller while spreading it; applying another layer of fiber adhesive mixture; and repeating the above operation 2 to 4 times with a scraper and roller to obtain a composite assembly containing 3 to 5 layers of needle-punched glass fiber mat; and then hot-pressing it at 220 to 230°C and 0.3 to 0.4 MPa for 2 to 4 minutes. The fiber adhesive mixture, by weight, comprises 13-15 parts of polyvinyl alcohol water-soluble chopped fibers, 45-50 parts of chopped glass fibers, and 13-17 parts of sodium silicate powder; Step 2, Aging and gelling: The short-cut needle-punched glass fiber mat obtained in Step 1 is placed in a drying room with a relative humidity of 70%, a temperature of 50°C and a carbon dioxide content of 4% for 10 hours, or aged in air at room temperature and relative humidity of 50% for 10 days, or blown evenly on the surface of the short-cut needle-punched glass fiber mat at 45°C, a carbon dioxide pressure of 0.6MPa and a blowing pressure of 0.35MPa, and blown on both sides of the short-cut needle-punched glass fiber mat surface. When blowing on one side, the blowing time is maintained for 100 seconds. Step 3, glue removal: Immerse the aged, gelled short-cut needle-punched glass fiber mat board, which is fixed between the wire mesh clamps, in hot water at 95-100℃ for 1-2 hours to remove polyvinyl alcohol. Then, open the wire mesh clamps, remove the board, and air dry it at room temperature to obtain the final product.

2. The production process of the glass fiber fireproof and heat-insulating core material according to claim 1, characterized in that, The fiber adhesive mixture in the first step may also include ferrosilicon powder, the mass of which is 3% to 5% of the mass of solid sodium silicate.

3. The production process of the glass fiber fireproof and heat-insulating core material according to claim 1, characterized in that, The polyvinyl alcohol water-soluble short-cut fiber is a 1.56 dtex × 38 mm polyvinyl alcohol water-soluble short-cut fiber with a melting point of 76–95 °C.

4. The production process of the glass fiber fireproof and heat-insulating core material according to claim 1, characterized in that, The chopped glass fibers have a length of 3–24 mm and a diameter of 10–14 μm.

5. The production process of the glass fiber fireproof and heat-insulating core material according to claim 1, characterized in that, The modulus of the sodium silicate powder is 3.1 to 3.4.