Heat-preservation high-elasticity glass fiber felt

Abstract

A preparation method of the heat-preservation high-elasticity glass fiber felt comprises the following steps: 1) modifying glass fibers; 2) performing alkali treatment on the hollow glass beads; 3) cutting the modified glass fibers into long modified glass fibers and short modified glass fibers; respectively carding, screening and mixing to form uniform long modified glass fiber filaments and short modified glass fiber filaments; 4) adding the alkali-treated hollow glass beads into an epoxy resin binder, respectively dipping glass fiber filaments into the epoxy resin binder, taking out the glass fiber filaments, and respectively paving the glass fiber filaments on a mesh belt to form long and short modified glass fiber mesh meshes; the method comprises the following steps of (1) preparing long and short modified glass fiber silk screens, (2) laminating the long and short modified glass fiber silk screens layer by layer to form an original felt, forming a single-layer secondary felt, laminating multiple layers of the single-layer secondary felt, extruding and tightening to form a primary felt, (6) baking, elastically releasing and shaping the primary felt, and (7) trimming, sealing and cutting off the formed felt baked at high temperature to obtain the finished heat-preservation high-elasticity glass fiber felt.

Description

Technical Field

[0001] The invention relates to a glass fiber-based thermal insulation material, in particular to a glass fiber felt. Background Art

[0002] Elastic felt made of glass fiber is mainly used for the insulation of LNG storage tanks. It is installed between the inner and outer tank walls, generally between the inner tank wall and the expanded perlite layer, to relieve the pressure of the expanded perlite on the inner tank side caused by the temperature change caused by the feeding or withdrawal of the tank. With the increasing application of LNG natural gas, the corresponding demand for tank insulation materials is also increasing. Glass fiber, as the raw material of elastic felt, has good insulation, strong heat resistance, good corrosion resistance, high mechanical strength and The Chinese patent document CN117107440A discloses a high and low temperature resistant glass fiber mat. The modified glass fiber is used to improve the dispersion performance of the glass fiber and the combination performance with the curing agent, and a high temperature resistant curing agent is used, thereby improving the performance of the glass fiber mat. However, in further research, we found that the thermal insulation performance of this glass fiber mat is not very ideal and the density is too large. Therefore, providing a glass fiber mat with better thermal insulation performance, lower density and equivalent or better tensile performance has become an urgent problem to be solved in the prior art. Summary of the invention

[0003] In order to solve the above technical problems, the present invention provides a new glass fiber mat, which is improved on the basis of the existing glass fiber mat to obtain a glass fiber mat with better thermal insulation performance and high elasticity. The technical solution adopted by the present invention is to provide a thermal insulation high elastic glass fiber mat, and the preparation method of the glass fiber mat includes: 1) Glass fiber modification: Add glass fiber to toluene, stir for 20-30 minutes, then add toluene solution of 2,4-diisocyanate, mix well, pass nitrogen protection, react at 80-90°C for 2-4 hours, wait for the product to cool, filter and separate the solid sample, wash, and vacuum dry to obtain isocyanate-modified glass fiber; add isocyanate-modified glass fiber to xylene, stir for 20-30 minutes, then add sodium lignin sulfonate and catalyst, mix well, pass nitrogen protection, react at 50-60°C for 1-3 hours, filter and dry after the reaction is completed to obtain modified glass fiber. 2) Alkali treatment of hollow glass microspheres The hollow glass microspheres are immersed in an alkali metal hydroxide solution with a concentration of 0.1-0.2 mol / L for alkali treatment at a temperature of 50-60° C. for a treatment time of 1-3 h. After the treatment, the alkali-treated hollow glass microspheres are washed with purified water and dried to obtain alkali-treated hollow glass microspheres.

[0004] 3) Cutting the modified glass fiber into long modified glass fiber with a length of 145-150 mm and short modified glass fiber with a length of 45-50 mm; combing, screening and mixing the long and short modified glass fibers respectively to form uniform long modified glass fiber filaments and short modified glass fiber filaments; 4) Add alkali-treated hollow glass microspheres to epoxy resin binder, immerse long modified glass fiber filaments and short modified glass fiber filaments in epoxy resin binder respectively, take them out after complete immersion, and lay them on mesh belts respectively to form long and short modified glass fiber meshes, wherein the mass ratio of alkali-treated hollow glass microspheres to epoxy resin binder is 2-5:100; 5) The long and short modified glass fiber meshes are stacked in the order of one layer of long modified glass fiber mesh and one layer of short modified glass fiber mesh to form an original felt with a thickness of 9.5-10.5 mm, and then the original felt is folded and bent to form a single-layer secondary felt with the same length and width, and then the single-layer secondary felt is stacked in multiple layers, and then extruded and tightened to form a primary felt; 6) Send the primary felt into a high-temperature tunnel furnace to bake, release its elasticity and shape it; 7) After high-temperature baking, the formed glass fiber felt is trimmed, sealed and cut to obtain a finished thermal insulation high-elastic glass fiber felt.

[0005] The thermal insulation high-elastic glass fiber felt further has a fiber diameter of 8-10 μm and a true density of the hollow glass microspheres of 0.15-0.2 g / ml, preferably 3MK20 / K15 / S15 hollow glass microspheres.

[0006] Furthermore, in step 1), the catalyst is dibutyltin dilaurate.

[0007] Furthermore, in step 4), the epoxy resin adhesive comprises the following raw materials in parts by weight: 70-80 parts of epoxy resin, 5-10 parts of modified polyamide amine curing agent, 1-3 parts of toughening agent, and 1-5 parts of white carbon black.

[0008] Furthermore, in step 4), the mass ratio of the alkali-treated hollow glass microspheres to the epoxy resin adhesive is 3-4:100.

[0009] The heat-insulating high-elastic glass fiber mat provided by the present invention is compared with the glass fiber mat in the prior art. By optimizing the ratio and specification of the hollow glass microspheres added to the binder and performing alkali treatment on the surface of the hollow glass microspheres, it is unexpectedly found that when the addition ratio is appropriate, the tensile strength and heat insulation performance of the glass fiber mat can be maintained or improved while the product density is reduced. In particular, the further preferred addition ratio of the hollow glass microspheres can significantly reduce the material density of the glass fiber mat, improve the tensile strength, and significantly reduce the thermal conductivity. DETAILED DESCRIPTION

[0010] In order to make the present invention clearer and more specific, the technical solution of the present invention is further described in detail below. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0011] 1. Preparation of epoxy resin adhesive 5 g of polyamide amine and 100 mL of toluene were mixed and stirred evenly, and then 3.5 g of 4-maleimide butyric acid, 0.5 g of 1,3-dicyclohexylcarbodiimide and 0.05 g of 4-dimethylaminopyridine were added, and the mixture was reacted at 50° C. for 8 h. After the reaction was completed, the solvent was removed by distillation under reduced pressure, and the mixture was washed and dried in vacuo to obtain a modified polyamide amine curing agent; wherein the number of terminal active amino groups of the polyamide amine was 4, and then 80 parts of bisphenol A epoxy resin E-51, 10 parts of modified polyamide amine curing agent, 3 parts of epoxidized SBS and 5 parts of white carbon black were mixed evenly, stirred at room temperature for 2 h, and discharged to obtain an epoxy resin adhesive.

[0012] 2. A method for making a heat-insulating high-elastic glass fiber felt includes the following steps 1) Glass fiber modification 5 g of glass fiber with a diameter of 8 μm was added to 100 mL of toluene, stirred at a speed of 1200 r / min for 30 min, then 4.2 g of toluene-2,4-diisocyanate was added, mixed evenly, nitrogen was passed through for protection, and the reaction was carried out at 80°C for 3 h. After the product was cooled, the solid sample was filtered and separated, washed, and vacuum dried to obtain isocyanate-modified glass fiber; 2 g of isocyanate-modified glass fiber was added to 60 mL of xylene, stirred at a speed of 1200 r / min for 20 min, then 5.2 g of sodium lignin sulfonate and 0.1 g of dibutyltin dilaurate were added, mixed evenly, nitrogen was passed through for protection, and the reaction was carried out at 50°C for 2 h. After the reaction was completed, it was filtered and dried to obtain modified glass fiber.

[0013] 2) Alkali treatment of hollow glass microspheres The 3MK20 hollow glass microspheres were immersed in a sodium hydroxide solution with a concentration of 0.1 mol / L for alkali treatment at a temperature of 50°C to 60°C for 3 hours. After the treatment, the alkali-treated hollow glass microspheres were washed with purified water and dried to obtain alkali-treated hollow glass microspheres.

[0014] 3) Cutting the modified glass fiber into long modified glass fiber with a length of 150 mm and short modified glass fiber with a length of 50 mm; 4) Add alkali-treated hollow glass microspheres to epoxy resin binder, immerse long modified glass fiber filaments and short modified glass fiber filaments in epoxy resin binder respectively, take them out after complete immersion, and lay them on a mesh belt moving at 0.5 m / min to form long and short modified glass fiber meshes; the mass ratio of alkali-treated hollow glass microspheres to epoxy resin binder is A:100 5) The long and short modified glass fiber meshes are stacked in the order of one layer of long modified glass fiber mesh and one layer of short modified glass fiber mesh to form an original felt with a thickness of 9.5 mm, and then the original felt is folded and bent to form a single-layer secondary felt of 50 mm × 50 mm, and then the single-layer secondary felt is stacked in multiple layers, and then squeezed and tightened to form a primary felt. 6) Send the primary felt into a high-temperature tunnel furnace, bake it at 180°C for 5 minutes, and then release its elasticity and set it; 7) After high-temperature baking, the formed glass fiber felt is trimmed, sealed and cut to obtain heat-insulating and highly elastic glass fiber felt.

[0015] The relevant parameters of the embodiments and comparative examples are shown in the table below.

[0016] The heat-insulating high-elastic glass fiber felts prepared in the examples and comparative examples were cut into test samples that met the specifications, and the density (GB / T5480-2017), tensile strength (GB / T17911-2018), and thermal conductivity at 0°C (GB / T10294-2008) of the samples were tested respectively. The results are shown in the following table

[0017] The test results show that the glass fiber felt samples obtained in Examples 1 to 4, compared with the comparative example referring to the CN117107440A technical solution, have a reduced density while basically maintaining equivalent or better tensile and thermal insulation properties. In particular, the samples provided in Examples 2 / 3 have a significantly reduced material density while improving tensile strength and significantly reducing thermal conductivity.

Claims

1. A thermal insulation high elastic glass fiber felt, characterized in that: The preparation method of the glass fiber mat comprises: 1) Glass fiber modification: Add glass fiber to toluene, stir for 20-30 minutes, then add toluene solution of 2,4-diisocyanate, mix well, pass nitrogen protection, react at 80-90°C for 2-4 hours, wait for the product to cool, filter and separate the solid sample, wash, and vacuum dry to obtain isocyanate-modified glass fiber; add isocyanate-modified glass fiber to xylene, stir for 20-30 minutes, then add sodium lignin sulfonate and catalyst, mix well, pass nitrogen protection, react at 50-60°C for 1-3 hours, filter and dry after the reaction is completed to obtain modified glass fiber. 2) Alkali treatment of hollow glass microspheres The hollow glass microspheres are immersed in an alkali metal hydroxide solution with a concentration of 0.1-0.2 mol / L for alkali treatment at a temperature of 50-60° C. for a treatment time of 1-3 h. After the treatment, the hollow glass microspheres are washed with purified water and dried to obtain alkali-treated hollow glass microspheres; 3) Cutting the modified glass fiber into long modified glass fiber with a length of 145-150 mm and short modified glass fiber with a length of 45-50 mm; combing, screening and mixing the long and short modified glass fibers respectively to form uniform long modified glass fiber filaments and short modified glass fiber filaments; 4) Add alkali-treated hollow glass microspheres to epoxy resin binder, immerse long modified glass fiber filaments and short modified glass fiber filaments in epoxy resin binder respectively, take them out after complete immersion, and lay them on mesh belts respectively to form long and short modified glass fiber meshes, wherein the mass ratio of alkali-treated hollow glass microspheres to epoxy resin binder is 2-5:100; 5) The long and short modified glass fiber meshes are stacked in the order of one layer of long modified glass fiber mesh and one layer of short modified glass fiber mesh to form an original felt with a thickness of 9.5-10.5 mm, and then the original felt is folded and bent to form a single-layer secondary felt with the same length and width, and then the single-layer secondary felt is stacked in multiple layers, and then extruded and tightened to form a primary felt; 6) Send the primary felt into a high-temperature tunnel furnace to bake, release its elasticity and shape it; 7) After high-temperature baking, the formed glass fiber felt is trimmed, sealed and cut to obtain a finished thermal insulation high-elastic glass fiber felt.

2. The heat-insulating high-elastic glass fiber mat according to claim 1, characterized in that: The fiber diameter of the glass fiber is 8-10 μm, and the true density of the hollow glass microspheres is 0.15-0.2 g / ml.

3. The heat-insulating high-elastic glass fiber mat according to claim 1, characterized in that: In step 1), the catalyst is dibutyltin dilaurate.

4. The heat-insulating high-elastic glass fiber mat according to claim 1, characterized in that: In step 4), the epoxy resin adhesive comprises the following raw materials in parts by weight: 70-80 parts of epoxy resin, 5-10 parts of modified polyamide amine curing agent, 1-3 parts of toughening agent, and 1-5 parts of white carbon black.

5. A thermal insulation high elastic glass fiber mat as claimed in any one of claims 1 to 4, characterized in that: Step 4) The mass ratio of the alkali-treated hollow glass microspheres to the epoxy resin adhesive is 3-4:100.

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