Rubber and plastic gradient porous heat preservation and sound insulation material and preparation method thereof

Abstract

The invention relates to the technical field of building materials, in particular to a rubber and plastic gradient porous heat preservation and sound insulation material and a preparation method thereof. Comprising the following steps: carrying out gradient calcination on kaolin to obtain metakaolin, carrying out gradient calcination on halloysite nanotubes, and carrying out nitrogen protection to obtain pretreated halloysite nanotubes; metakaolin, a composite activator, the pretreated halloysite nanotubes, aluminum powder and deionized water are mixed, subjected to high-speed shearing and vacuum defoaming, cured for 18-24 h and then subjected to high-pressure steam treatment and microwave treatment, and a porous material is obtained; the preparation method comprises the following steps: carrying out surface treatment on a porous material by using a silane coupling agent, carrying out melt blending on the treated porous material, ethylene propylene diene monomer and polypropylene, adding a composite foaming agent, carrying out compression molding, and setting a temperature gradient in a mold to obtain the rubber-plastic gradient porous heat-preservation and sound-insulation material. The kaolin material adopted by the rubber and plastic gradient porous heat preservation and sound insulation material is low in price, and the prepared finished product is good in heat preservation and sound insulation effect, high in compressive strength and suitable for being applied to multiple scenes.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of building materials, in particular to an oroplast gradient porous heat-insulating and sound-insulating material and a preparation method thereof. BACKGROUND

[0002] In the field of building, oroplast has become one of the main materials in the building industry due to low cost, and is widely used in the building industry. However, in the field of building, not only sufficient strength is required, but also good heat-insulating and sound-insulating effects are required. Under the condition of increasingly scarce energy, building energy saving is one of the important links related to the construction of low-carbon economy, the completion of energy saving and emission reduction targets and the sustainable development of economy in China. Therefore, a heat-insulating and sound-insulating material with good heat-insulating and sound-insulating effects and low energy consumption is needed. SUMMARY

[0003] In view of the above problems, the application provides an oroplast gradient porous heat-insulating and sound-insulating material and a preparation method thereof. The method is simple, and the prepared oroplast gradient porous heat-insulating and sound-insulating material has good heat-insulating and sound-insulating effects and low energy consumption.

[0004] In order to achieve the above purpose, the application provides a preparation method of an oroplast gradient porous heat-insulating and sound-insulating material, which comprises the following steps: S1, gradient calcination of kaolin is performed to obtain metakaolin, and gradient calcination of halloysite nanotubes is performed under nitrogen protection to obtain pretreated halloysite nanotubes; In the above reaction process, the kaolin loses crystal water step by step during gradient calcination, generates amorphous metakaolin, the layered structure of the kaolin is destroyed at high temperature, hydroxyl groups are released, high-activity silico-aluminate is formed, and active sites are provided for subsequent alkali activation. In the gradient calcination process, the layered structure is destroyed, amorphous substances are generated, and micropores and mesopores are formed in the amorphous phase in a disordered state. The halloysite nanotubes are gradient calcined to remove surface adsorbed water and organic matter, expose more hydroxyl groups and silico-alumina active sites, and enhance the binding capacity with the matrix. Nitrogen protection can avoid oxidation, retain the tubular structure of halloysite, and prevent high-temperature collapse.

[0005] S2, the metakaolin, the composite activator, the pretreated halloysite nanotubes, the aluminum powder and the deionized water are mixed, high-speed shearing is performed, vacuum defoaming is performed, and then curing is performed for 18-24 hours. Subsequently, high-pressure steam treatment and microwave treatment are performed to obtain a porous material; In the above reaction process, the metakaolin and the composite activator are mixed under high-speed shearing. In an alkaline environment, the silico-aluminate is depolymerized, the silicon-oxygen bond and the aluminum-oxygen bond are destroyed, and active monomers [SiO4] 4- , [AlO4] 5-, through the condensation of three-dimensional network gel, through high pressure steam treatment to promote secondary hydration reaction, high temperature and high pressure accelerate water molecule penetration, promote gel densification, form stable mesoporous, microwave radiation through dielectric heating to promote ion diffusion, both synergistically improve the porosity.

[0006] S3, the porous material is surface treated with silane coupling agent, then melt blended with ethylene propylene diene rubber, polypropylene in a twin screw extruder, then add composite foaming agent, mold forming, temperature gradient is set in the mold, obtain rubber plastic gradient porous thermal and sound insulation material.

[0007] The above process of silane coupling agent treatment of porous material surface, form Si-O-Si bond, enhance the interface bonding of ethylene propylene diene rubber, polypropylene, composite foaming agent is azodicarbonamide and H2O2, mold center high temperature makes azodicarbonamide decompose to generate N2, form microporous, low temperature edge promotes H2O2 decomposition to produce O2 form macroporous, realize the control of pore size grading.

[0008] Further, the kaolin is gradient calcined, the temperature rising rate is 8-10℃ / min at 25-600℃, and the temperature is kept for 1-1.5h, then the temperature is raised to 850℃ at a rate of 5-6℃ / min and calcined for 2-3h.

[0009] Further, the halloysite nanotube is gradient calcined, the temperature rising rate is 8-10℃ / min at 25-300℃, and the temperature is kept for 0.5-1h, then the temperature is raised to 650℃ at a rate of 5-6℃ / min and calcined for 3-4h.

[0010] Further, the composite activator is composed of water glass with modulus of 1.2-1.6 and NaOH, and the mass ratio of water glass to NaOH is 3-4:1.

[0011] Further, the metakaolin, composite activator, pretreated halloysite nanotube, aluminum powder and deionized water are mixed, and the mass ratio of metakaolin, composite activator, pretreated halloysite nanotube, aluminum powder and deionized water is 50-55:20-25:15-20:5-10:10-15.

[0012] Further, the high speed shearing is at a speed of 1200-1500rpm for 10-15min.

[0013] Further, the vacuum degassing is at a vacuum degree of 0.09-0.1MPa for 15-20min.

[0014] Further, the curing is at a temperature of 35-40℃ and a humidity of 80-85%.

[0015] Further, the high-pressure steam treatment has a temperature of 120-125 DEG C, saturated steam, and a time of 1-1.5 h.

[0016] Further, the microwave treatment has a power of 280-320 W and a time of 25-35 min.

[0017] Further, the porous material, the ethylene-propylene-diene rubber, the polypropylene, and the composite foaming agent in step S3 are 40-50 parts of the porous material, 20-30 parts of the ethylene-propylene-diene rubber, 15-20 parts of the polypropylene, and 5-10 parts of the composite foaming agent by weight.

[0018] Further, the composite foaming agent is composed of azodicarbonamide and H2O2, and the mass ratio of azodicarbonamide to H2O2 is 4-6:1.

[0019] Further, the melt blending has a barrel zone 1 temperature of 120-140 DEG C, a barrel zone 2 temperature of 140-160 DEG C, a barrel zone 3 temperature of 180-200 DEG C, and a die temperature of 170-180 DEG C, and a shear rate of 1200-1400 s -1 .

[0020] Further, the mold forming has a center temperature of 200-210 DEG C and an edge temperature of 160-180 DEG C.

[0021] The application also provides a preparation method of the rubber-plastic gradient porous thermal and sound insulation material.

[0022] In summary, the application has the following beneficial effects: The rubber-plastic gradient porous thermal insulation and sound insulation material prepared in the application adopts gradient calcination on kaolin and halloysite nanotubes, loses crystal water at 25-600 DEG C stage, gradually destroys the layered structure at 600-850 DEG C to form amorphous material, improves the reaction activity, and forms micropores and mesopores, can prevent partial crystal type conversion when directly calcined at 850 DEG C, reduces the reaction activity and excessive destruction of the layered structure to reduce the porosity, the halloysite nanotubes remove the surface adsorbed water and the residual organic matter in the channel at 25-300 DEG C stage, remove the structural hydroxyl at 300-650 DEG C to form amorphous silicate, optimize the pore of the tube wall, maintain the tubular structure, prevent the tube wall from being broken and the porosity from being reduced when directly calcined at 650 DEG C, the porous structure formed by adding metakaolin and halloysite nanotubes blocks the heat convection by closing the pores, and the gradient pore structure (mesopore, macropore and micropore) realizes the hierarchical blocking of the heat conduction path, the macropore absorbs low-frequency sound waves through Helmholtz resonance, the micropore dissipates energy through viscous damping and heat conduction, the mesopore inhibits the propagation of phonons through the quantum confinement effect, the gradient pore structure produces multi-stage scattering on the sound wave, destroys the coherence of the sound wave propagation, reduces the transmittance, the interface of the halloysite nanotube is rough, causes the sound wave to be diffusely reflected, and inhibits the energy transmission of the sound wave, the kaolin reduces the lattice distortion caused by thermal stress through gradient calcination, forms metakaolin after calcination, maintains the compressive strength, improves the reaction activity, generates C-S-H gel through alkali activation, the tubular structure of the halloysite nanotube forms a physical template in the mixing process, guides the directional growth of the gel network along the tube wall, the metakaolin gel fills the lumen of the halloysite nanotube to form a core-shell structure, the halloysite nanotube still maintains the tubular structure at high temperature, the Al-O-Al bond can absorb thermal stress, prevents cracking caused by phase transition of the metakaolin, maintains the high-strength skeleton, and the halloysite nanotube can reduce the damage of the tubular structure caused by thermal shock and oxidation through gradient calcination and nitrogen protection, and retains the tubular structure and strength. The rubber-plastic gradient porous thermal insulation and sound insulation material prepared in the application adopts the cheap kaolin material, has good thermal insulation and sound insulation effect, high compressive strength, and is suitable for multiple scene applications. DETAILED DESCRIPTION

[0023] The technical solutions in the embodiments of the application will be clearly and completely described below in combination with the embodiments of the application. Obviously, the described embodiments are only part of the embodiments of the application, rather than all the embodiments of the application. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the application.

[0024] The raw materials involved in the specific embodiments of the application are analytical pure. In addition, the particle size of the aluminum powder is 10-30 μm, the molecular weight of the polypropylene is 200000-500000, the concentration of H2O2 is 60%, the average diameter of the glass fiber is 5 μm, and the density is 48 kg / m 3 .

[0025] Example 1 A preparation method of an elastomer-plastic gradient porous thermal insulation and sound insulation material, comprising the following steps: S1, taking kaolin in a muffle furnace for gradient calcination, the temperature rising rate is 8 ℃ / min from 25-600 ℃, and the temperature is kept for 1 h, then the temperature is raised to 850 ℃ at a rate of 5 ℃ / min and calcined for 2 h, to obtain metakaolin, and taking halloysite nanotubes in a muffle furnace for gradient calcination, the temperature rising rate is 8 ℃ / min from 25-300 ℃, and the temperature is kept for 0.5 h, then the temperature is raised to 650 ℃ at a rate of 5 ℃ / min and calcined for 3 h, the whole process is protected by nitrogen, to obtain pretreated halloysite nanotubes; S2, mixing metakaolin, composite activator, pretreated halloysite nanotubes, aluminum powder and deionized water, the mass ratio of metakaolin, composite activator, pretreated halloysite nanotubes, aluminum powder and deionized water is 50:20:15:5:10, the composite activator is composed of sodium silicate with modulus 1.4 and NaOH, and the mass ratio is 3:1, then high-speed shearing (rotation speed 1200 rpm, time 15 min) is carried out, then vacuum degassing (vacuum degree 0.09 MPa, time 20 min) is carried out, then curing at temperature 35 ℃ and humidity 80% for 18 hours, then high-pressure steam treatment (temperature 120 ℃, saturated steam, time 1.5 h), then microwave treatment (power 280 W, time 35 min) is carried out, to obtain a porous material; S3, 40 parts of the porous material are immersed with silane coupling agent KH-550 (concentration 10%) for 10 min, the mass ratio of the porous material to the silane coupling agent KH-550 is 1:2, then melt blending with 20 parts of ethylene-propylene-diene rubber and 15 parts of polypropylene in a twin-screw extruder (barrel zone 1 temperature 120 ℃, barrel zone 2 temperature 140 ℃, barrel zone 3 temperature 180 ℃ and die head temperature 170 ℃, shear rate 1200 s -1 ), then 5 parts of composite foaming agent (azo dimethylamide and H2O2 mass ratio 4:1) is added, and molding is carried out, the temperature gradient is set in the mold (center temperature 200 ℃, edge temperature 160 ℃), to obtain an elastomer-plastic gradient porous thermal insulation and sound insulation material.

[0026] Example 2 A preparation method of an elastomer-plastic gradient porous thermal insulation and sound insulation material, comprising the following steps: S1, take kaolin in muffle furnace for gradient calcination, 25-600℃ heating rate is 9℃ / min, keep warm 1h, then with rate 5℃ / min to 850℃ calcination 2h, obtain metakaolin, take halloysite nanotube in muffle furnace for gradient calcination, 25-300℃ heating rate is 9℃ / min, keep warm 0.5h, then with rate 5℃ / min to 650℃ calcination 3h, nitrogen protection is carried out throughout the process, obtain pretreated halloysite nanotube; S2, the metakaolin, composite activator, pretreated halloysite nanotube, aluminum powder, deionized water is mixed, the mass ratio of metakaolin, composite activator, pretreated halloysite nanotube, aluminum powder, deionized water is 52:22:18:8:12, the composite activator is composed of modulus 1.4 sodium silicate and NaOH, the mass ratio is 4:1, then high speed shearing (rotating speed 1300rpm, time 12min), then vacuum degassing (vacuum degree 0.095MPa, time 18min), then curing at temperature 40℃, humidity 85% for 20 hours, then high pressure steam treatment (temperature 120℃, saturated steam, time 1.5h), then microwave treatment (power 300W, time 30min), obtain porous material; S3, 45 parts of porous material are immersed with silane coupling agent KH-550 (concentration 10%) for 10min, the mass ratio of porous material and silane coupling agent KH-550 is 1:2, then melt blending with 25 parts of ethylene propylene diene rubber, 18 parts of polypropylene in double screw extruder (barrel zone 1 temperature 140℃, barrel zone 2 temperature 160℃, barrel zone 3 temperature 190℃ and die head temperature 180℃, shear rate 1200s -1 ), then add 8 parts of composite foaming agent (azo dimethylamide and H2O2 mass ratio is 5:1), mold forming, set temperature gradient in the mold (center temperature is 205℃, edge temperature is 170℃), obtain rubber plastic gradient porous thermal insulation and sound insulation material.

[0027] Example 3 A method for preparing a rubber plastic gradient porous thermal insulation and sound insulation material, comprising the following steps: S1, take kaolin in muffle furnace for gradient calcination, 25-600℃ heating rate is 10℃ / min, keep warm 1h, then with rate 6℃ / min to 850℃ calcination 2h, obtain metakaolin, take halloysite nanotube in muffle furnace for gradient calcination, 25-300℃ heating rate is 10℃ / min, keep warm 0.5h, then with rate 6℃ / min to 650℃ calcination 3h, nitrogen protection is carried out throughout the process, obtain pretreated halloysite nanotube; S2, mix metakaolin, composite activator, pretreated halloysite nanotube, aluminum powder, deionized water, the mass ratio of metakaolin, composite activator, pretreated halloysite nanotube, aluminum powder, deionized water is 55:25:20:10:15, the composite activator is composed of sodium silicate with modulus 1.4 and NaOH, the mass ratio is 4:1, then high-speed shearing (rotation speed 1300 rpm, time 12 min), then vacuum degassing (vacuum degree 0.1 MPa, time 20 min), then curing at temperature 40℃, humidity 85% for 24 hours, then high-pressure steam treatment (temperature 125℃, saturated steam, time 1h), then microwave treatment (power 320W, time 25min), obtain porous material; S3, 50 parts of porous material are immersed with silane coupling agent KH-550 (concentration 10%) for 10 min, the mass ratio of porous material and silane coupling agent KH-550 is 1:2, then melt blending with 30 parts of ethylene propylene diene rubber and 20 parts of polypropylene in a twin-screw extruder (barrel zone 1 temperature 140℃, barrel zone 2 temperature 160℃, barrel zone 3 temperature 190℃ and die head temperature 180℃, shear rate 1200s -1 ), then add 10 parts of composite foaming agent (azo dimethylamide and H2O2 mass ratio 6:1), mold forming, set temperature gradient in the mold (center temperature 210℃, edge temperature 180℃), obtain rubber-plastic gradient porous thermal and sound insulation material.

[0028] Comparative Example 1 This comparative example is different from Example 3 in that halloysite nanotubes are directly calcined at 650℃ for 3h.

[0029] Comparative Example 2 This comparative example is different from Example 3 in that glass fibers are used instead of porous material.

[0030] Comparative Example 3 This comparative example is different from Example 3 in that the preparation method of a rubber-plastic gradient porous thermal and sound insulation material includes the following steps: S1, calcine kaolin in a muffle furnace, 25-600℃ at a rate of 10℃ / min, keep warm for 1h, then heat to 850℃ at a rate of 6℃ / min, calcine for 2h, obtain metakaolin, calcine halloysite nanotubes in a muffle furnace, 25-300℃ at a rate of 10℃ / min, keep warm for 0.5h, then heat to 650℃ at a rate of 6℃ / min, calcine for 3h, nitrogen protection throughout the process, obtain pretreated halloysite nanotubes; S2, the metakaolin, composite activator, pretreated halloysite nanotubes, aluminum powder, deionized water were mixed, the mass ratio of metakaolin, composite activator, pretreated halloysite nanotubes, aluminum powder, deionized water was 55:25:20:10:15, the composite activator was composed of modulus 1.4 water glass and NaOH, the mass ratio was 4:1, then high speed shearing (rotating speed 1300 rpm, time 12 min) was carried out, then vacuum degassing (vacuum degree 0.1 MPa, time 20 min) was carried out, then curing at temperature 40℃, humidity 85% for 24 hours, then high pressure steam treatment (temperature 125℃, saturated steam, time 1h), then microwave treatment (power 350W, time 25 min) was carried out, and the porous material was obtained; S3, 50 parts of the porous material were immersed with silane coupling agent KH-550 (concentration 10%) for 10 min, the mass ratio of the porous material and the silane coupling agent KH-550 was 1:2, then melt blending with 30 parts of ethylene propylene diene rubber and 20 parts of polypropylene in a twin-screw extruder (barrel zone 1 temperature 140℃, barrel zone 2 temperature 160℃, barrel zone 3 temperature 190℃ and die head temperature 180℃, shear rate 1200s -1 ), then 10 parts of composite foaming agent (azo dimethylamide and H2O2 mass ratio 6:1) was added, and molding (temperature 180℃) was carried out, and the rubber-plastic gradient porous thermal insulation and sound insulation material was obtained.

[0031] Performance test The rubber-plastic gradient porous thermal insulation and sound insulation materials prepared in examples 1-3 and comparative examples 1-3 were functionally tested.

[0032] Thermal insulation test: GB / T 10294-2008 "Determination of Steady-State Thermal Resistance and Related Properties of Thermal Insulation Materials - Guarded Hot Plate Method" was used to measure the thermal conductivity; Sound insulation test: GB / T 19889.3-2005 "Acoustics - Measurement of sound insulation in buildings and of building elements using sound statistical methods - Part 3: Measurement of airborne sound insulation in buildings and of building elements" was used to measure the sound insulation at 2000 Hz; Compressive strength test: the rubber-plastic gradient porous thermal insulation and sound insulation materials prepared in examples 1-3 and comparative examples 1-3 were prepared into 1200mm×800mm×50mm plates, and a universal testing machine Instron 5965 was used for testing, equipped with a compression clamp, the contact area was 50mm×50mm, the loading speed was 10 mm / min, and the compressive strength was calculated.

[0033] The test results are shown in Table 1: Table 1

[0034] As shown in Table 1, the rubber-plastic gradient porous thermal and sound insulation material prepared in the embodiments of the present application has excellent performance, low thermal conductivity, high sound insulation effect and high compressive strength, and the rubber-plastic gradient porous thermal and sound insulation material prepared in Example 2 has the best performance; the difference between Comparative Example 1 and Example 3 is that the halloysite nanotubes are directly calcined at 650℃ for 3h, and the results show that the thermal conductivity, sound insulation effect and compressive strength are not as good as those of Example 3; since the halloysite nanotubes are directly calcined at 650℃, the tubular structure is damaged and the wall collapses due to thermal shock, the compressive strength is reduced, the pore structure is changed, and the comprehensive performance is reduced; the difference between Comparative Example 2 and Example 3 is that the traditional thermal and sound insulation material glass fiber is used instead of the porous material, and the test results show that the thermal conductivity, sound insulation and compressive strength of Comparative Example 2 are similar to those of Example 3, indicating that the porous material prepared from kaolin can replace the thermal and sound insulation effect of glass fiber, and the price of kaolin is much lower than that of glass fiber, which can effectively reduce the energy consumption of the material; the difference between Comparative Example 3 and Example 3 is that the temperature is set to 180℃ during the step S3 of molding, resulting in low porosity of the prepared rubber-plastic gradient porous thermal and sound insulation material, and thus the thermal and sound insulation effect is reduced, and the comprehensive effect is not as good as that of Example 3.

[0035] In summary, the rubber-plastic gradient porous thermal and sound insulation material prepared in the embodiments of the present application has good thermal insulation, sound insulation and compressive effect, and the effect of Example 2 is the best, and the best embodiment of the present application is Example 2.

[0036] The above is only an example and description of the concept of the present application, and those skilled in the art can make various modifications or supplements or use similar ways to replace the described specific embodiments, as long as they do not deviate from the concept of the invention or exceed the scope defined by the present claims, and should belong to the protection scope of the present application.

Claims

1. A method for preparing a rubber-plastic gradient porous thermal insulation and sound insulation material, characterized in that, Includes the following steps: S1. Kaolin was subjected to gradient calcination to obtain metakaolin. Halloysite nanotubes were subjected to gradient calcination under nitrogen protection to obtain pretreated halloysite nanotubes. S2. Mix metakaolin, composite activator, pretreated halloysite nanotubes, aluminum powder, and deionized water, perform high-speed shearing, vacuum degassing, and then cure for 18-24 hours. Afterward, treat with high-pressure steam and microwave to obtain porous material. S3. The porous material is surface-treated with a silane coupling agent, then melt-blended with EPDM rubber and polypropylene in a twin-screw extruder, followed by the addition of a composite foaming agent, and then molded. A temperature gradient is set in the mold to obtain a rubber-plastic gradient porous thermal insulation and sound insulation material.

2. The method for preparing a rubber-plastic gradient porous thermal insulation and sound insulation material according to claim 1, characterized in that, The kaolin is subjected to gradient calcination, with a heating rate of 8-10℃ / min from 25-600℃, and then calcined at 850℃ for 2-3 hours at a rate of 5-6℃ / min.

3. The method for preparing a rubber-plastic gradient porous thermal insulation and sound insulation material according to claim 1, characterized in that, The halloysite nanotubes were subjected to gradient calcination, with a heating rate of 8-10℃ / min from 25-300℃, followed by calcination at 5-6℃ / min to 650℃ for 3-4 hours.

4. The method for preparing a rubber-plastic gradient porous thermal insulation and sound insulation material according to claim 1, characterized in that, The composite activator is composed of water glass with a modulus of 1.2-1.6 and NaOH, with a mass ratio of water glass to NaOH of 3-4:

1.

5. The method for preparing a rubber-plastic gradient porous thermal insulation and sound insulation material according to claim 1, characterized in that, The mixture consists of metakaolin, a composite activator, pretreated halloysite nanotubes, aluminum powder, and deionized water, with a mass ratio of 50-55:20-25:15-20:5-10:10-15.

6. The method for preparing a rubber-plastic gradient porous thermal insulation and sound insulation material according to claim 1, characterized in that, The vacuum degassing process is performed at a vacuum level of 0.09-0.1 MPa for 15-20 minutes.

7. The method for preparing a rubber-plastic gradient porous thermal insulation and sound insulation material according to claim 1, characterized in that, The porous material, EPDM rubber, polypropylene, and composite foaming agent mentioned in step S3 are, by weight, 40-50 parts porous material, 20-30 parts EPDM rubber, 15-20 parts polypropylene, and 5-10 parts composite foaming agent.

8. The method for preparing a rubber-plastic gradient porous thermal insulation and sound insulation material according to claim 1, characterized in that, The composite foaming agent is composed of azodicarbonamide and H2O2, with a mass ratio of azodicarbonamide to H2O2 of 4-6:

1.

9. The method for preparing a rubber-plastic gradient porous thermal insulation and sound insulation material according to claim 1, characterized in that, The molding process is performed at a temperature of 200-210°C at the center and 160-180°C at the edge.

10. A rubber-plastic gradient porous thermal insulation and sound insulation material prepared by the preparation method of the rubber-plastic gradient porous thermal insulation and sound insulation material according to any one of claims 1-9.

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