Thermal insulation material with high flame retardance and preparation method thereof

Abstract

According to the invention, the insulating material according to the invention is produced from raw materials containing the following components: a. 30-70% by weight of expanded perlite, b. 10-30% by weight of hydrophobic silica, c. 10-30% by weight of an aqueous dispersion, e. The invention relates to an aqueous flame-retardant composition comprising the following raw materials: (a) an aqueous flame retardant selected from the group consisting of aqueous polyurethane dispersions, aqueous polychloroprene dispersions, aqueous polyacrylate dispersions and mixtures of at least two of these dispersions, d. 3 to 25 wt% of expandable graphite, e. 0 to 15 wt% of a halogen-free flame retardant, and f. 0.2 to 2.5 wt% of a hydrophobing agent, where the amounts are all relative to the total weight of the raw materials. The invention also provides a preparation method of the thermal insulation material and a product containing the thermal insulation material.

Description

Technical Field

[0001] The invention relates to a thermal insulation material and a preparation method thereof, as well as a product containing the thermal insulation material. Background Art

[0002] With the booming construction industry and the modernization of buildings, the consumption of thermal insulation materials (also known as insulation panels and insulation materials) in construction projects has increased annually. Exterior wall insulation effectively blocks the conduction of heat energy and is highly effective. It not only saves winter heating costs but is also more environmentally friendly than other heating methods.

[0003] Currently, the thermal protection materials used in my country primarily include organic and inorganic materials. Organic thermal protection materials offer excellent insulation and energy-saving properties, but are flammable. Inorganic thermal protection materials, on the other hand, are safe and reliable, but offer poor thermal protection. Polyurethane rigid foam thermal protection material is a new composite material that offers thermal insulation, heat preservation, and waterproofing. Its thermal conductivity is low, at only 0.022-0.033 W / (m*K), which is half that of extruded sheet and significantly lower than Class A flame-retardant thermal protection materials. It has the lowest thermal conductivity of current thermal protection materials and can be applied to building exterior walls for insulation and heat preservation. However, as a polyurethane rigid foam thermal protection material is an organic thermal protection material, its maximum flame retardancy can only reach or fall below Class B1 according to GB8624-2016, "Classification on Burning Behavior for Building Materials," and therefore fails to meet the Class A flame retardancy requirements for thermal protection materials in the construction industry.

[0004] At present, common Class A flame retardant thermal protection materials on the market include foamed cement boards, vacuum insulation panels, foamed glass, glass wool, inorganic thermal insulation mortar, rock wool boards, foamed ceramic boards, etc. Foamed cement boards have excellent thermal protection properties, but have high water absorption, poor long-term weather resistance, and are prone to collapse problems. The vacuum degree of vacuum insulation panels is difficult to maintain. Once they are damaged, the thermal insulation performance of the board drops sharply. In addition, existing construction techniques result in too many board joints and thermal bridges, which pose a great risk of moisture condensation. The thermal conductivity of foamed glass is 0.062W / (m*K), and its thermal insulation and insulation efficiency is low, and the cost is expensive. Glass wool has good thermal protection properties, but its acidity coefficient is ≤1.6. It cannot be plastered and cannot meet the requirements of the exterior wall thermal protection system. The thermal conductivity of inorganic thermal insulation mortar is 0.070W / (m*K), its thermal insulation and insulation efficiency is low, and construction is difficult. Rock wool boards have excellent thermal protection and fire resistance, but their inherent strength is low, and they have poor waterproof performance and poor material stability. Foamed ceramic boards are non-flammable, but their thermal conductivity is 0.055W / (m*K), and their thermal insulation and heat insulation efficiency are low.

[0005] Expanded perlite thermal protection materials made using water glass as an adhesive have become a popular product in the thermal protection materials field due to their low cost, simple production process, and excellent thermal protection. However, expanded perlite thermal protection materials made using water glass as an adhesive inherently contain high concentrations of sodium ions, which causes the Si-O-Si bonds that function as an adhesive to reversibly degrade. Consequently, the thermal protection material suffers from a significant loss of mechanical strength after a period of use, resulting in poor weather resistance. The degradation of the Si-O-Si bonds also causes sodium ions to migrate to the exterior of the wall, leading to alkali backflow on the wall surface, resulting in mottled or even peeling walls.

[0006] CN106045459B discloses an expanded perlite thermal protection material made using a multimetallic phosphate adhesive. The multimetallic phosphate adhesive is based on aluminum hydroxide, Group IIA metal oxides, and transition metal oxides. A polymer emulsion, such as styrene-acrylic emulsion, JS emulsion, emulsified asphalt, or modified acrylic emulsion, is used as the adhesive. The expanded perlite thermal protection material has a Class A flame retardancy rating, low bond strength, and a thermal conductivity of 0.060 W / m*K, but also exhibits low thermal insulation and insulation efficiency.

[0007] CN105948642B discloses a hydrophobically modified expanded perlite thermal protection material, which includes cement, fly ash, propyltrimethoxysilane, polyacrylate emulsion, modified expanded perlite, sodium dodecylbenzenesulfonate, additives, quicklime, PP fiber hydroxypropyl methylcellulose, bentonite, and the like. The processing of this thermal protection material is complex, time-consuming, and has low production efficiency. The thermal protection material has a flame retardancy rating of Class A and a thermal conductivity of 0.050 W / m*K, indicating low thermal insulation and insulation efficiency.

[0008] CN105948637B discloses a fiber-reinforced modified expanded perlite thermal protection material and its production method. The modified expanded perlite thermal protection material is made from cement, fly ash, PP fiber, and other organic or inorganic substances and industrial and mining waste. The material is heated to 1000-1300°C for expansion and then sprayed with silicone for hydrophobic treatment. The resulting modified expanded perlite thermal protection material has a Class A flame retardant rating, relatively low bond strength, and a thermal conductivity of 0.051 W / (m*K). However, it also exhibits low thermal insulation and heat retention efficiencies.

[0009] CN103803885A relates to an inorganic modified insulation board and a manufacturing method thereof. The solution is: its components and component qualities are as follows: expanded perlite, foamed cement particles, foamed ceramic particles, expanded glass particles, crystalline alginate light particles, expanded graphite, or oxide microbead particles, or a mixture of two or more thereof; expandable polystyrene particles, modified expandable polystyrene particles, extruded polystyrene particles, or modified extruded polystyrene particles; modified polyurethane rigid foam, or phenol- or polyurea-modified particles, or one or two thereof, or a mixture thereof; the inorganic gelling material is ordinary cement, aluminum-magnesium cement, stone cement, rapid-hardening cement, or water glass, or one or a mixture of at least two thereof; the waterproofing agent is calcium hardate, mechanical silicon, or pyruvic acid emulsion; the flame retardant is aluminum oxide, aluminum oxide, polyaluminum silicate, or red wax; and fly ash and / or graphite. The thermal conductivity of this solution is 40-60mW / mK; the insulation efficiency is low.

[0010] CN103821236A, CN102249600A, CN105948641B, CN105967581A, and CN105967581A disclose modified waterproof insulation boards based on different materials, such as expanded perlite, chemical microbeads, and nano-silica sol, and their production methods. However, these methods have the common disadvantage of low thermal conductivity and insulation efficiency.

[0011] CN115973484A discloses a thermal insulation material based on expanded perlite, aqueous polyurethane dispersion, expanded graphite and a water repellent. The use of hydrophobic silica as an additional component is not disclosed.

[0012] Currently, China has implemented energy-saving standards of 65%-75%, and high-rise building insulation must use flame-retardant Class A materials. If buildings are to meet these energy-saving and flame-retardant standards, they urgently need Class A high-flame-retardant insulation materials that possess excellent flame retardancy, low thermal conductivity, high adhesion, and high mechanical strength to meet environmental protection, energy conservation, and emission reduction requirements.

[0013] It is hoped to develop a new thermal insulation material that meets the above requirements. SUMMARY OF THE INVENTION

[0014] The object of the present invention is to provide a thermal insulation material and a preparation method thereof, as well as a product containing the thermal insulation material.

[0015] The thermal insulation material according to the present invention is made of raw materials containing the following components:

[0016] a. 30-70 wt% expanded perlite,

[0017] b. 10% to 30% by weight of hydrophobic silica,

[0018] c. 10% to 30% by weight of an aqueous dispersion selected from the group consisting of aqueous polyurethane dispersions, aqueous polychloroprene dispersions, aqueous polyacrylate dispersions and mixtures of at least two of these dispersions,

[0019] d. 3% to 25% by weight of expandable graphite,

[0020] e. 0-15 wt% of halogen-free flame retardant and

[0021] f. 0.2 wt% to 2.5 wt% of a hydrophobic agent,

[0022] The above amounts are all relative to the total weight of the raw materials.

[0023] According to one aspect of the present invention, a method for preparing the thermal insulation material provided by the present invention is provided, wherein component a) expanded perlite, component b) hydrophobic silica, component c) an aqueous dispersion selected from: an aqueous polyurethane dispersion, an aqueous polychloroprene dispersion, an aqueous polyacrylate dispersion, and a mixture of at least two of these dispersions, component d) expandable graphite, component e) a halogen-free flame retardant, and component f) a hydrophobizing agent are mixed in any manner and dried to obtain the thermal insulation material.

[0024] According to another aspect of the present invention, a product is provided, comprising the thermal insulation material provided according to the present invention.

[0025] The thermal insulation material of the present invention has low density, low thermal conductivity, high water repellency and high oxygen index, and the thermal insulation material is not damaged after being burned. The thermal insulation material of the present invention has good mechanical strength, flame retardancy and thermal insulation performance.

[0026] Details

[0027] The present invention provides that the thermal insulation material according to the present invention is made from raw materials containing the following components: a. 30% to 70% by weight of expanded perlite, b. 10% to 30% by weight of hydrophobic silica, c. 10% to 30% by weight of an aqueous dispersion selected from the group consisting of aqueous polyurethane dispersions, aqueous polychloroprene dispersions, aqueous polyacrylate dispersions, and mixtures of at least two of these dispersions, d. 3% to 25% by weight of expandable graphite, e. 0% to 15% by weight of a halogen-free flame retardant, and f. 0.2% to 2.5% by weight of a hydrophobizing agent, wherein the above amounts are all relative to the total weight of the raw materials. The present invention also provides a method for preparing the thermal insulation material and an article containing the thermal insulation material.

[0028] The solid of the dispersion of the present invention refers to the solid component of the dispersion or the effective component of the dispersion.

[0029] Insulation materials

[0030] The thermal insulation material preferably meets at least one of the following characteristics:

[0031] A. ≤250kg / m3 measured according to GB / T 5486-2008 3 , preferably 90-250kg / m 3 , more preferably 110kg / m 3 -200kg / m 3 density;

[0032] B. Thermal conductivity ≤46mw / mK 30-46mw / mK measured at 25°C according to GB / T 10294-2008; and

[0033] C. Oxygen index ≥43, preferably 43-100, measured according to GB / T2406.2-2009,

[0034] D. Hydrophobicity measured according to GB / T 10299-2011 of ≥95%, preferably 95%-100%.

[0035] Component a) Expanded perlite

[0036] The expanded perlite of the present invention is a natural acidic glassy volcanic rock and a non-metallic mineral.

[0037] Preferably, the expanded perlite is derived from one or more of the following: perlite, retinite, and obsidian.

[0038] The expanded perlite is preferably perlite sand.

[0039] The expanded perlite preferably meets at least one of the following characteristics:

[0040] i. A volume expansion coefficient of 4-20, preferably 4-10, measured according to "JC / T 209-2012Standard";

[0041] ii. 30kg / m3 measured according to JC / T209-2012 3 -120 kg / m 3 , preferably 60kg / m 3 -120kg / m 3 density;

[0042] iii. a thermal conductivity of 20 mW / mK-70 mW / mK, preferably 25 mW / mK-60 mW / mK, more preferably 25 mW / mK-45 mW / mK, measured according to GB / T 10294 or GB / T 10295;

[0043] iv. a product hydrophobicity of not less than 95% measured according to GB / T 10299; and

[0044] v. A closed porosity of less than 10% as measured in accordance with Appendix D of JC / T 1042-2007.

[0045] The volume expansion coefficient of expanded perlite is tested as follows: 5 mL of expanded perlite is placed in a 30 mL porcelain crucible, which is then placed in a high-temperature furnace preheated to 250°C-450°C for 8-20 minutes. The expanded perlite is removed and allowed to cool. The volume of the expanded perlite is recorded as V1. The crucible is then quickly poured into a 1000°C porcelain evaporating dish and immediately returned to the high-temperature furnace for 10-20 seconds. After expansion, the crucible is cooled and transferred to a 10 mL graduated cylinder, which is shaken up and down to prevent any change. The volume of the expanded perlite is recorded as V2, and the volume expansion coefficient = V2 / V1.

[0046] The amount of expanded perlite is preferably 40% to 66% by weight relative to the total weight of the raw materials.

[0047] Component b) hydrophobic silica

[0048] Hydrophilic silica can be prepared, for example, by flame hydrolysis of chlorosilanes and is chemically very pure. It carries silanol groups on its surface. Therefore, it has a high affinity for water, is hydrophilic, and is completely wetted by water. Alkyl or alkoxy groups can be chemically anchored to its surface by reaction of the silanol groups with organosilicon compounds. The resulting product is then no longer wetted by water and is hydrophobic.

[0049] Suitable hydrophobizing agents are, for example, organochlorosilanes or organobromosilanes of the formula:

[0050] R 1 R 2 R 3 SiHal, R 1 R 2 SiHal2 or R 1 SiHal3, wherein Hal can be Br or Cl, preferably Cl, and wherein R 1 、R 2 and R 3 may be the same or different and each is a C1-C6 alkyl group, a fluoroalkyl group, an aryl group or an arylalkyl group. 1 、R2 and R 3 Each is preferably a C1-C3 alkyl group, but each is more preferably a methyl group.Most preferably, the hydrophobizing agent is chlorotrimethylsilane or dimethyldichlorosilane.

[0051] Further suitable hydrophobizing agents are, for example, organosiloxanes or organosilazanes of the formula:

[0052] (R 1 R 2 R 3 Si)2X, where R 1 、R 2 and R 3 may be the same or different and are each C1-C6 alkyl, fluoroalkyl, aryl or arylalkyl, and wherein X is O or NH. 1 、R 2 and R 3 Each is preferably C1-C3 alkyl, and X is O or NH. More preferably, R 1 、R 2 and R 3 is methyl, and X is O or NH, in which case the hydrophobic agent is hexamethyldisiloxane or hexamethyldisilazane.

[0053] Further suitable hydrophobic agents are, for example, 1 R 2 SiO units, preferably 3, 4 or 5 R 1 R 2 SiO unit cyclic organosiloxane, where R 1 and R 2 may be the same or different and are each a C1-C6 alkyl group, a fluoroalkyl group, an aryl group or an arylalkyl group. 1 and R 2 Each is preferably a C1-C3 alkyl group. 1 and R 2 More preferred is methyl, in which case the hydrophobic agent is hexamethylcyclotrisiloxane or octamethylcyclotetrasiloxane or decamethylcyclopentasiloxane.

[0054] Further suitable hydrophobic agents are, for example, 1 R 2 R 3 Si-O-[(SiR 1 R 2 )-O] n -SiR 1 R 2 R 4 A linear organosiloxane wherein n is an integer from 0 to 15, R 1 and R 2may be the same or different and are each a C1-C6 alkyl group, a fluoroalkyl group, an aryl group or an arylalkyl group, R 3 and R 4 can be the same or different and are each hydroxy, C1-C6 alkyl, fluoroalkyl, aryl or arylalkyl. 1 and R 2 Can be C1-C3 alkyl, and more advantageously, each is methyl. In a preferred embodiment, the linear organosiloxane is octamethyldisiloxane (n is 1, and R 1 -R 4 is methyl). Also preferred are hydroxyl-terminated linear organosiloxanes in which R 3 is a hydroxyl group, and R 4 is a C1-C6 alkyl group, preferably a methyl group, or R 3 and R 4 are all hydroxyl groups, such as HO-[Si(CH3)2-O-] 15 H.

[0055] Further suitable hydrophobic agents are, for example, 1 Z 2 Z 3 Si-(CH2)xY organosiloxane, where Z 1 、Z 2 and Z 3 may be the same or different and each is a C1-C6 alkoxy group (ie, OR', wherein R' = C1-C6 alkyl) or a C1-C6 alkyl group, provided that Z 1 、Z 2 and Z 3 At least one of the above is a C1-C6 alkoxy group, and wherein x is an integer from 1 to 10, and wherein Y is methyl, fluoroalkyl, aryl or arylalkyl, -NH2, -N3, -SCN, -CH=CH2, -OOC(CH2)CH=CH2, -OCH2-CH(O)CH2, -NH-COO-CH3, -NH-COO-CH2-CH3, -NH-(CH2)3Si(OR")3 (wherein R" is C1-C6 alkyl), -Sx-(CH2)3Si(OR")3 (wherein R" is C1-C6 alkyl). A preferred organosiloxane of the above formula is (R'O)3Si-(CH2)xY, wherein R' is C1-C6 alkyl, preferably methyl, and wherein x is an integer from 1 to 10, and wherein Y is methyl, fluoroalkyl, aryl or arylalkyl, for example trimethoxyoctylsilane.

[0056] The hydrophobic agents mentioned above are intended to be examples only. Other suitable hydrophobic agents may also be used.

[0057] Those skilled in the art will readily recognize the conditions under which the aforementioned hydrophobization reaction can be carried out and the means by which the resulting hydrophobized silica can be recovered. Suitable methods are described, for example, in US 6,344,240 B, US 2006 / 0292192 A1, and US 5,776,240 B.

[0058] Suitable hydrophobic silicas that can be used to prepare the thermal insulation materials of the present invention are available under the trade name Purchased, for example, as H13L, H15, H15L, H20, H30, H2000, H17 and H18.

[0059] Component c) Aqueous Dispersion

[0060] The amount of aqueous dispersion is preferably 15% to 30% by weight, most preferably 15% to 25% by weight, relative to the total weight of the raw materials.

[0061] The solid content of the aqueous dispersion is preferably 10 wt% to 70 wt%, more preferably 30 wt% to 65 wt%, and most preferably 35 wt% to 60 wt%, relative to the total weight of the aqueous dispersion.

[0062] The aqueous dispersion has a minimum heat activation temperature of the adhesive layer of preferably 40°C to 120°C, most preferably 50°C to 100°C.

[0063] The aqueous dispersion may be added to the raw materials in the form of a dispersion, or may be obtained by adding in the form of a solid polymer and water followed by mixing, and is most preferably added directly in the form of a dispersion.

[0064] The aqueous dispersion is selected from the group consisting of aqueous polyurethane dispersions, aqueous polychloroprene dispersions, aqueous polyacrylate dispersions and mixtures of at least two of these dispersions.

[0065] Suitable aqueous polyurethane dispersions are preferably one or more of the following: anionic aqueous polyurethane dispersions and nonionic aqueous polyurethane dispersions, most preferably anionic aqueous polyurethane dispersions.

[0066] The anionic aqueous polyurethane dispersion contains hydrophilic anionic groups, preferably in an amount of 0.1 to 15 milliequivalents per 100 grams of polyurethane solids, and most preferably in an amount of 1.6 to 14 milliequivalents per 100 grams of polyurethane solids.

[0067] The residual content of the organic solvent in the aqueous polyurethane dispersion is preferably less than 1.0 wt % relative to the total weight of the aqueous polyurethane dispersion.

[0068] The aqueous polyurethane dispersion comprises a polyurethane polymer and water, wherein the polyurethane polymer has a melting enthalpy greater than 3 J / g, preferably 20 J / g to 100 J / g, most preferably 30 J / g to 50 J / g, and the melting enthalpy is measured by DSC measurement in the range of 20° C. to 100° C. in the first heating curve according to DIN 65467:1999.

[0069] Suitable aqueous polyurethane dispersions according to the invention are available under the trade name U is commercially available from Covestro Polymer Co., Ltd., as e.g. U53, U54, U56, U58, U62 and U8755.

[0070] Suitable aqueous polychloroprene dispersions according to the invention are, for example, "Ullmanns dertechnischen Chemie", Vol. 9, p. 366, Verlag Urban und Schwarzenberg, Munich-Berlin 1957; "Encyclopedia of Polymer Science and Technology", Vol. 3, pp. 705-730, John Wiley, New York 1965; "Methoden der Organischen 30 Chemie" (Houben-Weyl) XIV / 1, 738f. Georg Thieme Verlag Stuttgart 1961, WO-A 02 / 24825 (p. 3, line 26 - p. 7, line 4), DE-A 3002734 (p. 8, line 23 - p. 12, line 9), US-A The preparation of aqueous polychloroprene dispersions by emulsion polymerization of chloroprene optionally containing ethylenically unsaturated monomers copolymerizable with chloroprene in an aqueous alkaline medium is disclosed in WO-A 02 / 24825 (column 2, line 9 to column 4, line 45) or in WO-A 2009027013. Particularly preferred aqueous polychloroprene dispersions are prepared by continuous polymerization as described, for example, in Example 2 of WO-A 02 / 24825 and in Example 6 of DE 3002734, where the amount of chain transfer agent can be varied between 0.01% and 0.3%.

[0071] Suitable aqueous polychloroprene dispersions according to the invention are available under the trade name C is commercially available from Covestro Polymer Co., Ltd., as e.g. C 74, C 84, C 2325 and C 2372.

[0072] Suitable aqueous polyacrylate dispersions are aqueous primary or secondary polyacrylate dispersions comprising polyacrylate polymers and water.

[0073] Suitable aqueous polychloroprene dispersions according to the invention are available under the trade name A is commercially available from Covestro Polymer Co., Ltd., as e.g. A 2846, A 2427 and A 2457.

[0074] Component d) expandable graphite

[0075] The expandable graphite preferably meets at least one of the following characteristics:

[0076] I. a particle size of 50 mesh to 200 mesh, preferably 80 mesh to 180 mesh, more preferably 100 mesh to 150 mesh, measured according to GB T 3520-2008 graphite fineness test method; and

[0077] II. The expansion ratio is 50-500, and the expansion ratio is measured according to GB 10698-1989.

[0078] The amount of expandable graphite is preferably 5% to 25% by weight relative to the total weight of the raw materials.

[0079] Component e) halogen-free flame retardant

[0080] The halogen-free flame retardant is preferably a phosphorus-containing flame retardant, more preferably a powdered intumescent phosphorus-containing flame retardant, and most preferably ammonium polyphosphate.

[0081] The amount of the halogen-free flame retardant is preferably 0-12.5 wt % relative to the total weight of the raw materials.

[0082] Component f) hydrophobic agent

[0083] The hydrophobic agent is preferably a polysiloxane water repellent, most preferably a powdered polysiloxane water repellent.

[0084] The amount of the hydrophobizing agent is preferably 0.5 to 2.5 wt % relative to the total weight of the raw materials.

[0085] Preparation method

[0086] The method for preparing the thermal insulation material comprises at least the following steps:

[0087] 1. Component a) expanded perlite, component b) hydrophobic SiO2, component c) an aqueous dispersion selected from the group consisting of aqueous polyurethane dispersions, aqueous polychloroprene dispersions, aqueous polyacrylate dispersions and mixtures of at least two of these dispersions, component d) expandable graphite, component e) a halogen-free flame retardant and component f) a hydrophobizing agent are mixed in any manner, and

[0088] 2. Dry to obtain thermal insulation material.

[0089] The aqueous dispersion (component c) can be added as is. However, the polymer and water can also be added as a single component in the first step. The mixture in the first step is stirred, preferably at an absolute pressure of ≥20 to ≤101,325 kPa, more preferably ≥60 to ≤95 kPa, and most preferably ≥62 to ≤92 kPa (absolute pressure is relative to a perfect vacuum of 0 kPa). This allows at least a portion of the hydrophobic silica to be filled into at least a portion of the at least partially open cells of the expanded perlite.

[0090] "Vacuum degree," as the name implies, refers to the degree of vacuum. It is a key parameter for vacuum extraction equipment such as vacuum pumps, micro vacuum pumps, micro air pumps, micro suction pumps, and micro suction pumps. "Vacuum" refers to a gas pressure within a given space that is less than 101,325 kPa (101,325 kPa is standard atmospheric pressure).

[0091] There are two ways to determine the vacuum level:

[0092] i) "Absolute pressure" and "absolute vacuum" (i.e., how much higher the pressure is than the "theoretical vacuum" (p vac-theor. =0KPa).

[0093] In practice, the absolute pressure of a vacuum pump is between 0 and 101.325 kPa. The absolute pressure should be measured at 20°C and an altitude of 0°C using an absolute pressure gauge. The initial value of the instrument used to measure vacuum (absolute vacuum gauge) is 101.325 kPa (i.e., standard atmospheric pressure).

[0094] ii) “Relative pressure” and “relative vacuum” (i.e., how much lower the pressure is than “atmospheric pressure”).

[0095] "Relative vacuum" refers to the difference between the pressure of the object being measured and the atmospheric pressure at the measurement site. This is measured using a standard vacuum gauge. In the absence of a vacuum (i.e., at normal pressure), the gauge's initial value is 0. When measuring a vacuum, the value ranges from 0 to -101.325 kPa (usually expressed as a negative number).

[0096] For example, there is a micro vacuum pump PH2506 B with a measurement value of -75 kPa. This means that the pump can draw a vacuum state of 75 kPa lower than the atmospheric pressure at the measurement site.

[0097] The term "vacuum degree" commonly used in the international vacuum industry is also the most scientific symbol of absolute pressure. It refers to "ultimate vacuum, absolute vacuum, and absolute pressure." However, due to its simple measurement methods and instrumentation, "relative vacuum degree" (relative pressure, gauge pressure, negative pressure) is very common and easy to measure. It is inexpensive and readily available, making it widely used. In theory, the two can be converted to each other, and the conversion method is as follows:

[0098] Relative vacuum = absolute vacuum (absolute pressure) - air pressure at the measurement location

[0099] For example, if the absolute pressure of the micro vacuum pump VM8001 is 80 kPa, its relative vacuum is approximately 80-100 = -20 kPa (assuming the pressure at the measurement site is 100 kPa). This should be displayed as -0.02 MPa on a normal vacuum gauge.

[0100] The mixture obtained from the first step can be poured into a mold cavity and optionally vibrated to compact the mixture and to release gases, such as air, that are optionally trapped in the mixture.

[0101] The second step of the above method is a drying step, which preferably includes one or more of the following methods: microwave heating, infrared heating, conventional heating and vacuum drying.

[0102] Preferred is a combination of vacuum drying and heating, wherein the drying temperature is preferably ≥60°C to ≤120°C and the absolute pressure is in the range of ≥20 to ≤101,325 kPa, more preferably ≥60 to ≤95 kPa, most preferably ≥62 to ≤92 kPa.

[0103] A preferred method for preparing the thermal insulation material is as follows: component a) expanded perlite, component b) hydrophobic silica, component c) aqueous dispersion, component d) expandable graphite, component e) halogen-free flame retardant and component f) hydrophobic agent are mixed in any manner, preferably uniformly stirred at an absolute pressure of ≥20 to ≤101,325 kPa, more preferably ≥60 to ≤95 kPa, most preferably ≥62 to ≤92 kPa to obtain a mixture, the mixture is placed in a mold cavity (wherein the pressure and temperature may be increased), gradually vibrated and pressurized to compact the mixture, and gas in the mixture is discharged, and then the temperature of the mold cavity is gradually increased at an absolute pressure of ≥20 to ≤101,325 kPa, more preferably ≥60 to ≤95 kPa, most preferably ≥62 to ≤92 kPa, preferably to ≥60°C to ≤120°C to dry the thermal insulation material, thereby reducing the moisture content to less than 3%, preferably less than 2%, and removing the thermal insulation material from the mold cavity.

[0104] Products

[0105] The articles are primarily structural products of current industry products and are preferably prefabricated building structural elements. Example

[0106] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which the invention belongs. In the event that the definition of a term used in this specification conflicts with the meaning commonly understood by those skilled in the art to which the invention belongs, the definition given herein shall prevail.

[0107] Unless otherwise indicated, all numbers expressing quantities of ingredients, reaction conditions, and so forth used in the specification and claims are to be understood as modified by the term “about.” Accordingly, unless indicated to the contrary, the numerical parameters set forth herein are approximations that may vary depending upon the desired properties to be obtained.

[0108] As used herein, the expression "and / or" means one or all of the referenced elements.

[0109] As used herein, "comprising" and "including" include the stated elements individually and the presence of other elements in addition to the stated elements.

[0110] Unless otherwise stated, all percentages herein are by weight.

[0111] Unless otherwise stated, all analyses and measurements in the present invention were performed at 23±2°C.

[0112] The oxygen index of the thermal insulation material is measured according to GB / T2406.2-2009, and the qualified value is not less than 43 (≥43). The higher the oxygen index, the better the flame retardancy.

[0113] The density of the insulation material is measured according to GB / T 5486-2008, and the qualified value is not higher than 250kg / m 3 (≤250kg / m 3 ). The lower the density, the lighter the material.

[0114] The thermal conductivity of the thermal insulation material is measured according to GB / T 10294-2008, and the qualified value is not higher than 46 mW / mK (≤46 mW / mK) at 25° C. The lower the thermal conductivity, the better the thermal insulation performance of the material.

[0115] The fire test of the thermal insulation material is carried out according to GB 8624-2012 Class A test. If there is no damage after the fire, the thermal insulation material is qualified, otherwise it is unqualified.

[0116] The hydrophobicity of the thermal insulation material is measured according to GB / T 10299-2011, and the qualified value is ≥95%. The higher the hydrophobicity, the better the thermal insulation performance of the material.

[0117] Raw materials and reagents

[0118] 44V20: Polymeric diphenylmethane diisocyanate (PMDI), NCO content 30.5%-31.5%, viscosity 140-260 mPa·s.

[0119] 48BA003: Polyurethane liquid composition.

[0120] U42: Aqueous polyurethane dispersion having a melting enthalpy of less than 3 J / g, a solid content of 48-52 wt % and a minimum heat activation temperature of the adhesive layer of 80-100° C., and is commercially available from Covestro Polymer Co., Ltd.

[0121] U58: an aqueous polyurethane dispersion having a melting enthalpy of 40.06 J / g, a solid content of 50±1 wt % and a minimum heat activation temperature of the adhesive layer of 50° C.-70° C., and is commercially available from Covestro Polymer Co., Ltd.

[0122] U54: an aqueous polyurethane dispersion having a melting enthalpy of 37.60 J / g, a solid content of 50±1 wt % and a minimum heat activation temperature of the adhesive layer of 60-70° C., and is commercially available from Covestro Polymer Co., Ltd.

[0123] U56: an aqueous polyurethane dispersion having a melting enthalpy of 44.00 J / g, a solid content of 49-51 wt % and a minimum heat activation temperature of the adhesive layer of 55-65° C., and is commercially available from Covestro Polymer Co., Ltd.

[0124] U8755: an aqueous polyurethane dispersion having a melting enthalpy of 39.68 J / g, a solid content of 45 wt % and a minimum heat activation temperature of the adhesive layer of 80-100° C., and is commercially available from Covestro Polymer Co., Ltd.

[0125] U62: Aqueous polyurethane dispersion having a melting enthalpy of 37.25 J / g, a solid content of 50±1 wt % and a minimum heat activation temperature of the adhesive layer of 50° C.-70° C., and is commercially available from Covestro Polymer Co., Ltd.

[0126] U 53: an aqueous polyurethane dispersion having a melting enthalpy of 41.55 J / g, a solid content of 40 wt % and a minimum heat activation temperature of the adhesive layer of 60-70° C., and is commercially available from Covestro Polymer Co., Ltd.

[0127] C 84: A colloidal aqueous dispersion of a 2-chloroprene polymer having a high crystallization rate, a nonvolatile content of 54.5-55.5%, an apparent viscosity of approximately 100 mPa·s (by Brookfield test method), a pH of approximately 13, and is commercially available from Covestro Polymer Co., Ltd.

[0128] C 2325: A colloidal aqueous dispersion of a 2-chloroprene polymer having a high crystallization rate, a nonvolatile content of 54-56%, an apparent viscosity of approximately 100 mPa·s (by Brookfield test method), a pH of approximately 12, and is commercially available from Covestro Polymer Co., Ltd.

[0129] SP-60: Pearlite sand, with a volume expansion coefficient of 40 and a density of 60 kg / m 3 , thermal conductivity of 23-26 mW / mK and closed porosity <10%, and can be purchased from Xinyang Zhongkai Insulation Material Co., Ltd.

[0130] H20: Specific surface area is 200m 2 / g of a type of hydrophobic SiO2 particles treated with dimethylsilane, available from Wacker Chemie AG.

[0131] H2000: Specific surface area is 200m 2 / g of a type of hydrophobic SiO2 particles treated with hexamethylsilane, available from Wacker Chemie AG.

[0132] EG-E300: expandable graphite with a purity of 95%-99%, a particle size of 50 mesh-80 mesh, an expansion rate>300 mL / g, and can be purchased from Qingdao Rock Sea carbonmaterial Co. Ltd.

[0133] AP 422: Ammonium polyphosphate, available from Clariant.

[0134] SPH60+: polysiloxane water repellent, available from Dow Corning.

[0135] SPH50: polysiloxane water repellent, available from Dow Corning.

[0136] Z6683: a polysiloxane water repellent, available from Dow Corning, and Z6683 used in the examples of the present invention is an emulsion obtained by mixing Z6683 and deionized water at a mass ratio of 1:7.

[0137] Tables 1, 2, and 3 show the composition of the raw materials of the thermal insulation materials of the embodiments of the present invention and the comparative examples and the performance test results of the thermal insulation materials, including product density, thermal conductivity, oxygen index, whether the structure is damaged after fire, and hydrophobicity.

[0138] Preparation of thermal insulation materials of Examples 1 to 18 and Comparative Examples 3 to 8

[0139] Expanded perlite, hydrophobic silica, expandable graphite, a flame retardant, and a water repellent were weighed and placed in a plastic cup according to the amounts shown in Table 1, Table 2, or Table 3, and the mixture was gently stirred with a stirring rod for approximately 5 minutes until the mixture became homogeneous to obtain a powdery substance;

[0140] An appropriate amount of deionized water is added to wet the surface of the powder material, and the powder material is stirred with a stirring rod for about 5 minutes until the powder material is slightly wetted and stirring no longer generates dust.

[0141] The mixture is stirred under vacuum at an absolute pressure of 62 to 92 kPa for 20 to 30 minutes.

[0142] Adding a polyurethane or polychloroprene aqueous dispersion according to the amount shown in Table 1, Table 2, or Table 3, and vigorously stirring to uniformly disperse the aqueous dispersion on the surface of the powder substance to form a mixture;

[0143] The mixture was poured into a square mold, and the mold was leveled with a spatula, compacted, and then placed in a vacuum oven (absolute pressure 82 KPa) preheated to 60° C. to 120° C. and heat-dried until the water content of the mixture was less than 3%.

[0144] Preparation of thermal insulation material of Comparative Example 1

[0145] The liquid composition and Desmodur 44V20 were mixed according to the amounts shown in Table 1 to obtain a mixture;

[0146] The mixture was poured into a square mold, and the mold was leveled with a scraper, compacted, and then placed in a vacuum oven preheated to 60° C.-120° C. and heat-dried until the water content of the mixture was less than 3% to obtain a comparative example insulation material.

[0147] Preparation of thermal insulation material of Comparative Example 2

[0148] According to the amount shown in Table 1, expanded perlite was weighed and placed in a plastic cup, which was gently stirred with a stirring rod for about 5 minutes until it became homogeneous to obtain a powdered substance;

[0149] An appropriate amount of deionized water is added to wet the surface of the powder material, and the powder material is stirred with a stirring rod for about 5 minutes until the powder material is slightly wetted and stirring no longer generates dust.

[0150] The liquid composition and Desmodur 44V20 were added according to the amounts shown in Table 1 and mixed to obtain a mixture;

[0151] The mixture was poured into a square mold, and the mold was leveled with a scraper, compacted, and then placed in a vacuum oven preheated to 60° C. to 120° C. and heat-dried until the water content of the mixture was less than 3% to obtain a comparative example insulation material.

[0152]

[0153] The compound used in Comparative Example 1 48BA003 and The combination of 44V20 is a polyurethane rigid foam insulation system, and the insulation material obtained therefrom has a low oxygen index, and the material structure is broken after a fire.

[0154] In Comparative Example 2, expanded perlite was added to 48BA003 and 44V20 polyurethane rigid foam insulation system, and the insulation material obtained therefrom has a low oxygen index, and the material structure is damaged after fire.

[0155] The raw material system of Comparative Example 3 contains expanded perlite, C2325 and polysiloxane water repellent, and the thermal insulation material obtained therefrom has a low oxygen index, and the material structure is damaged after fire.

[0156] The raw material system of Comparative Example 4 contained 75.5 wt% expanded perlite and only 8 wt% C2325, which cannot produce molded insulation materials and cannot be tested for performance.

[0157] The raw material system of Comparative Example 5 contains U42 has a melting enthalpy of less than 3 J / g and can be formed into thermal insulation materials, but the resulting materials are too soft to be tested for performance.

[0158] According to Comparative Example 6 The combination of C2325 with expanded perlite, expandable graphite, and a polysiloxane water repellent, but without hydrophobic silica and flame retardants, resulted in an insulation with an oxygen index of 40, which is still below the target value of at least 43.

[0159] The thermal insulation materials of Examples 1-8 of the present invention all met the required density, thermal conductivity, and oxygen index. Furthermore, the materials did not break or collapse after being burned, and the flames were extinguished after the materials were removed from the fire. Therefore, the thermal insulation materials of the embodiments of the present invention had good mechanical strength, thermal insulation properties, and flame retardancy.

[0160] Table 2: Composition and performance test results of raw materials of thermal insulation materials of Examples 9-14 and Comparative Example 7

[0161]

[0162] The raw material system of Comparative Example 7 contained 71% expanded perlite and only 7.5% by weight of U58, which cannot produce molded insulation materials and cannot perform performance testing.

[0163] The raw materials of Examples 9-14 contain different aqueous polyurethane dispersions. The resulting thermal insulation materials meet the required density, thermal conductivity, and oxygen index. Furthermore, the materials do not break or collapse after being burned, and the flames are extinguished after the materials are removed from the fire. Therefore, the thermal insulation materials of the present invention have excellent mechanical strength, thermal insulation properties, and flame retardancy.

[0164] Table 3: Composition and performance test results of raw materials of thermal insulation materials of Examples 11-16 and Comparative Example 8

[0165]

[0166] The raw materials of Comparative Example 8 did not contain the polysiloxane water repellent, and the molded thermal insulation material could not balance the oxygen index and the ignition performance, and the thermal insulation material had low hydrophobicity.

[0167] The raw materials of embodiment 15-18 contain different polysiloxane water repellents, and the density, thermal conductivity and oxygen index of the thermal insulation material of molding can meet the requirements, and the material is not damaged and collapsed after the fire, and the flame is extinguished after the material is away from the fire. Therefore, the thermal insulation material of embodiments of the present invention has good mechanical strength, thermal insulation performance and flame retardancy. In addition, the thermal insulation material of embodiment 15-18 has high hydrophobicity, and the thermal insulation performance of thermal insulation material is good.

[0168] It will be apparent to those skilled in the art that the invention is not limited to the details set forth, and that the invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The embodiments herein are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description; furthermore, any changes which fall within the meaning and range of equivalence of the claims should be considered as part of the present invention.

Claims

1. A thermal insulation material, which is made of raw materials containing the following components: a. 30-70 wt% expanded perlite, b. 10% to 30% by weight of hydrophobic silica, c. 10% to 30% by weight of an aqueous dispersion selected from the group consisting of aqueous polyurethane dispersions, aqueous polychloroprene dispersions, aqueous polyacrylate dispersions and mixtures of at least two of these dispersions, d. 3% to 25% by weight of expandable graphite, e. 0-15 wt% of halogen-free flame retardant and f. 0.2 wt% to 2.5 wt% of a hydrophobic agent, The above amounts are all relative to the total weight of the raw materials.

2. The thermal insulation material according to claim 1, characterized in that The expanded perlite is derived from one or more of the following: perlite, resin stone, and obsidian.

3. The thermal insulation material according to claim 1 or 2, characterized in that The expanded perlite satisfies at least one of the following characteristics: i. A volume expansion coefficient of 4-20, preferably 4-10, measured according to "JC / T 209-2012Standard"; ii. 30kg / m3 measured according to JC / T209-2012 3 -120 kg / m 3 , preferably 60kg / m 3 -120kg / m 3 density; iii. a thermal conductivity of 20 mW / mK-70 mW / mK, preferably 25 mW / mK-60 mW / mK, more preferably 25 mW / mK-45 mW / mK, measured according to GB / T 10294 or GB / T 10295; iv. a product hydrophobicity of not less than 95% as measured in accordance with GB / T 10299; and v. A closed porosity of less than 10% as measured in accordance with Appendix D of JC / T 1042-2007.

4. The thermal insulation material according to any one of claims 1 to 3, characterized in that The hydrophobic silica has been hydrophobized by at least one hydrophobizing agent selected from organochlorosilanes, organobromosilanes, organosiloxanes or organosilazanes, preferably by at least one organosiloxane.

5. The thermal insulation material according to any one of claims 1 to 4, characterized in that The aqueous polyurethane dispersion comprises a polyurethane polymer and water, and the polyurethane polymer has a melting enthalpy greater than 3 J / g, and the melting enthalpy is measured by DSC measurement in the range of 20° C. to 100° C. in the first heating curve according to DIN 65467:1999.

6. The thermal insulation material according to any one of claims 1 to 5, characterized in that The aqueous polyurethane dispersion is one or more of the following: anionic aqueous polyurethane dispersion and nonionic aqueous polyurethane dispersion, and anionic aqueous polyurethane dispersion is most preferred.

7. The thermal insulation material according to any one of claims 1 to 6, characterized in that The expandable graphite satisfies at least one of the following characteristics: I. a particle size of 50 mesh to 200 mesh, preferably 80 mesh to 180 mesh, more preferably 100 mesh to 150 mesh, measured according to GB T 3520-2008 graphite fineness test method; and II. The expansion ratio is 50-500, and the expansion ratio is measured according to GB 10698-1989.

8. The thermal insulation material according to any one of claims 1 to 7, characterized in that The halogen-free flame retardant is a phosphorus-containing flame retardant, preferably a powdered intumescent phosphorus-containing flame retardant, and more preferably ammonium polyphosphate.

9. The thermal insulation material according to any one of claims 1 to 8, characterized in that The hydrophobic agent is a polysiloxane water repellent, preferably a powdered polysiloxane water repellent.

10. The thermal insulation material according to any one of claims 1 to 9, characterized in that It meets at least one of the following characteristics: A. ≤250kg / m3 measured according to GB / T 5486-2008 3 , preferably 90-250kg / m 3 , more preferably 110kg / m 3 -200kg / m 3 density; B. a thermal conductivity of ≤46 mw / mK, preferably 30-46 mw / mK, measured at 25°C according to GB / T 10294-2008; and C. Oxygen index ≥43, preferably 43-100, measured according to GB / T2406.2-2009, D. Hydrophobicity measured according to GB / T 10299-2011 of ≥95%, preferably 95%-100%.

11. A method for preparing a thermal insulation material according to any one of claims 1 to 10, comprising at least the following steps:

1. Component a) expanded perlite, component b) hydrophobic SiO2, c) an aqueous dispersion selected from the group consisting of aqueous polyurethane dispersions, aqueous polychloroprene dispersions, aqueous polyacrylate dispersions and mixtures of at least two of these dispersions, component d) expandable graphite, component e) a halogen-free flame retardant and component f) a hydrophobizing agent are mixed in any manner, and 2. Drying to obtain the thermal insulation material.

12. The method according to claim 11, wherein The mixture in the first step is stirred, preferably at an absolute pressure of ≥20 to ≤101,325 kPa, more preferably ≥60 to ≤95 kPa, most preferably ≥62 to ≤92 kPa.

13. The method according to claim 11 or 12, wherein the second step is performed by one or more of the following methods: microwave heating, infrared heating, conventional heating and vacuum drying.

14. The method according to claim 12, wherein the second step is carried out by a combination of vacuum drying and heating, wherein the drying temperature is preferably in the range of ≥60°C to ≤120°C, and the absolute pressure is preferably in the range of ≥20 to ≤101,325 kPa, more preferably ≥60 to ≤95 kPa, most preferably ≥62 to ≤92 kPa.

15. An article comprising the thermal insulation material according to any one of claims 1 to 10.

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