Fireproof rock wool board for ship and preparation method thereof

Abstract

The present application relates to the field of building fire prevention technology, in particular to a fireproof rock wool board for ships and a preparation method thereof. The present application overcomes the problems of easy shrinkage, pulverization and collapse of rock wool board in fire, and poor salt mist aging resistance. By using titanate surface layer and high-density basalt wool activated in the subsurface as core material, using modified linear phenolic epoxy resin containing DOPO derivative, hexaphenoxycyclotriphosphazene and self-ceramization filler as reinforcing layer matrix, the present application covers active fire extinguishing modification of resin, high-pressure pulse activation of rock wool interface and three-stage gradient pressure synergistic curing process; through gas phase free radical capture mechanism, chemical fire extinguishing is realized, and by using low-melting glass powder and kaolin to construct dense ceramic skeleton in situ at high temperature, the obtained fireproof rock wool board for ships has A-grade non-combustibility, low smoke and non-toxic, and excellent high-temperature structural integrity.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of building fire protection technology, in particular to a fireproof rock wool board for ships and a preparation method thereof. BACKGROUND

[0002] With the increasingly stringent standards of the International Maritime Organization on ship fire safety, A-60 level fire-resistant partition structure has become the key defense line to protect the safety of life at sea and the survival ability of the ship. Rock wool board, as a typical inorganic non-metallic porous thermal insulation material, is widely used in the fireproof and thermal insulation system of various ship cabin partitions, deck ceilings and engine room equipment due to its low thermal conductivity, excellent heat preservation and sound absorption and noise reduction performance, as well as wide raw material sources. In particular, high-density rock wool board prepared with basalt as the main raw material has good chemical stability and certain mechanical strength at room temperature, and is an indispensable core material in the field of ship outfitting.

[0003] However, the general rock wool board for ships in the prior art still has technical defects that cannot be ignored in terms of fireproof performance when facing extreme high-temperature environments. First, in order to give the rock wool board the necessary compressive and tensile strength, ordinary thermosetting phenolic resin is often used as a binder in traditional processes; this kind of organic polymer material has limited heat resistance and will undergo intense pyrolysis and oxidation reaction at the initial stage of fire, resulting in complete failure of the bonding network, causing the rock wool fibers to lose their binding and powdering, peeling, or even collapsing, and losing the heat barrier function. Second, ordinary rock wool fibers themselves will soften and sinter when the temperature exceeds 800℃, and lack rigid skeleton support at high temperatures, resulting in serious linear shrinkage deformation of the board during A-60 level fire resistance testing, producing penetrating cracks, causing the backfire surface to rise too quickly or the flame to penetrate. In addition, the existing interface modification technology relies on traditional silane coupling agents, which are prone to hydrolysis reaction in the high-humidity and high-salt environment of the ocean, resulting in a significant decrease in the strength of the organic-inorganic interface after long-term service, further deteriorating the structural integrity of the material in the event of a fire.

[0004] In order to solve the problem of imperfect fireproof performance of traditional fireproof rock wool board, a fireproof rock wool board for ships and a preparation method thereof are proposed. SUMMARY

[0005] The present application aims to provide a fireproof rock wool board for ships and a preparation method thereof. The fireproof rock wool board for ships is prepared by using a high-density basalt wool activated by a titanate surface layer and a subsurface layer as a core material, using a modified linear phenolic epoxy resin containing a DOPO derivative, hexaphenoxycyclotriphosphazene and a self-ceramization filler as a reinforcing layer matrix, covering active fire-retardant modification of the resin, high-pressure pulse activation of the rock wool interface and a three-stage gradient pressure synergistic curing process. The chemical fire extinguishing is realized by a gas phase free radical capture mechanism, and a dense ceramic skeleton is constructed in situ by using low-melting glass powder and kaolin at high temperature, so that the fireproof rock wool board for ships has the advantages of A-grade non-combustibility, low smoke, non-toxicity and excellent high-temperature structural integrity.

[0006] To achieve the above-mentioned purpose, the present application provides the following technical scheme:

[0007] The present application provides a preparation method of a fireproof rock wool board for ships, and the preparation method is as follows: linear phenolic epoxy resin is added to a four-necked reaction kettle, the phenolic epoxy resin is F-51, the CAS is 28064-14-4, and the epoxy equivalent weight is 178 g / eq; under the protection of inert gas, microencapsulated fire extinguishing agent, flame-retardant synergist and fluxing glass powder are added, and after high-speed shearing dispersion, high-temperature resistant curing agent, ceramic skeleton filler and solvent are added, and self-ceramization resin slurry is prepared by degassing; the mixed micron-sized filler includes microencapsulated DOPO with a particle size of 5-10 μm, hexaphenoxycyclotriphosphazene with a particle size of 2-5 μm and low-melting glass powder with a particle size of 3-4 μm; the high-temperature resistant curing agent is 4,4'-diaminodiphenyl sulfone; the ceramic skeleton filler is flaky kaolin treated by calcination at 1250 DEG C; and the internal composition of the flaky kaolin treated by calcination at 1250 DEG C is changed from kaolinite phase to mullite phase.

[0008] The self-ceramization process of the self-ceramization resin slurry is as follows: stage one: resin decomposition and skeleton exposure (300-450 DEG C) the organic resin matrix is decomposed and carbonized by heat; at this time, the microencapsulated DOPO releases free radicals to extinguish fire, and the phosphazene promotes carbonization; the low-melting glass powder and the calcined kaolin, which are originally wrapped by the resin, begin to contact each other;

[0009] Stage two: liquid phase generation and bonding (480-600 DEG C) when the temperature reaches 480 DEG C, the low-melting glass powder begins to melt and becomes a high-viscosity liquid phase (like high-temperature glue), which quickly wets and coats the incombustible calcined kaolin particles and the fibers on the surface of the rock wool;

[0010] Stage three: eutectic reaction and porcelain formation (>800 DEG C) as the temperature continues to rise, the oxides (B2O3, SiO2) in the liquid phase glass powder react with the kaolin (Al2O3·SiO2) to generate a new high-temperature stable phase (such as mullite phase);

[0011] Final form: After cooling, a hard ceramic shell of rock wool fiber-kaolin skeleton-glass phase matrix trinity is formed, which blocks oxygen and heat, realizing self-ceramization.

[0012] Direct introduction of DOPO will affect the curing kinetics of epoxy resin (consumption of epoxy group) and reduce the glass transition temperature (Tg), so it is introduced in the form of microcapsulation. The preparation method of microcapsulated 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide is as follows: 10 parts of melamine and 20 parts of 37% formaldehyde aqueous solution are added to a three-necked flask, and the pH value is adjusted to 8.5-9.0 with triethanolamine;

[0013] 100 parts of deionized water are added to the reaction kettle, stirring is started, 3 parts of solid SMA-1000 powder are added, then 25% ammonia water is added dropwise, the pH value is adjusted to 8.5-9.0, and the temperature is raised to 90°C. Stirring at constant temperature for 40 min, under this condition, the anhydride ring in the SMA molecule undergoes ring-opening hydrolysis reaction to generate water-soluble styrene-maleic acid ammonium salt, and the solution changes from turbidity to clear and transparent.

[0014] The dissolved SMA aqueous solution is cooled to 60°C, and DOPO powder is added for high-speed shear emulsification; after emulsification, 10% citric acid solution is slowly added dropwise to adjust the pH value to 4.0-5.0 (at this time, the SMA partial group is protonated, but it still remains stable at the interface), and then melamine-formaldehyde prepolymer is added dropwise for coating reaction. Stir at 70°C for 45 min until the solution becomes transparent to prepare MF prepolymer solution; SMA is SMA-2000, and CAS is 9011-13-6;

[0015] The prepared MF prepolymer solution is slowly added to the DOPO suspension, the temperature is raised to 75°C, and low-speed stirring is carried out at 300 r / min. The pH value is maintained in an acidic environment of 4-5 to catalyze polycondensation. The reaction is carried out for 3 h, and the MF is in situ cross-linked and deposited on the surface of DOPO to form a capsule wall; filtration, washing with warm water for 3 times to remove unreacted substances, drying in a 100°C oven to constant weight to obtain a white powder with an average particle size of 5-10 μm and a coating rate of 86.4%.

[0016] The basalt wool board is surface treated to obtain a surface treated basalt wool board.

[0017] The self-ceramization resin slurry is scraped onto the alkali-free glass fiber grid cloth to obtain a semi-cured reinforced prepreg; the areal density of the alkali-free glass fiber grid cloth is 220 g / m², the mesh size is 4 mm×4 mm, and the grade is E.

[0018] The surface treated hard aluminum alloy foil, the surface treated basalt wool board and the semi-cured reinforced prepreg are laminated and gradiently cured to obtain a fireproof basalt wool board for ships.

[0019] Preferably, the basalt wool board is sprayed on both sides with an interface activation liquid; the interface activation liquid is prepared from isopropyl tri(dioctyl pyrophosphoric acyloxy) titanate coupling agent and epoxy resin. During the later processing, one end of the titanate holds the rock wool, and the other end of the long chain extends to the outside, and a small amount of epoxy resin is pre-dissolved in the activation liquid. Small molecule epoxy will preferentially penetrate into the micropores of the rock wool fibers and physically entangle or partially react with the long chain of the titanate; after drying, not only a single molecular coupling layer is formed on the surface of the rock wool, but also a very thin epoxy-rich pre-hung bottom layer is formed, which greatly improves the compatibility with the main resin in the subsequent process and prevents false adhesion.

[0020] Preferably, the gradient curing is one-stage exhaust and wetting, two-stage crosslinking and molding, and three-stage stress relief; the physical meaning of wetting is the degree of resin melt infiltration into rock wool fibers. At 120°C, the resin is in a molten state, the viscosity is at a minimum, but the curing reaction has not yet begun; low-viscosity fluid produces strong capillary siphon effect, can penetrate into the deep layer of rock wool fiber bundle (penetration depth can reach 3-5mm), and at the same time displace the air in the interstitial space of the fibers. This is the key physical window to prevent air bubbles from exploding in the subsequent high temperature and high pressure stage; if this wetting stage is missing, the resin will instantly solidify and block the surface at high temperature and high pressure, and the internal air cannot be discharged, forming dry spots and air inclusions.

[0021] Preferably, the flame retardant synergist is hexaphenoxycyclotriphosphazene; the fluxing glass powder is a low-melting-point glass powder. The low-melting-point glass powder has a softening point of 480°C and a flow point of 530°C-550°C; phenolic epoxy resin begins to undergo main chain rupture and pyrolytic carbonization at 400°C-450°C, at which point the resin matrix begins to lose adhesion, and the glass powder softens at 480°C, which is exactly at the critical point where the organic adhesion fails, providing seamless liquid physical adhesion to prevent the material from disintegrating during the transition from organic to inorganic; if the softening point is too high (>700°C), the board will powderize due to the lack of adhesive in the 450°C-700°C range; if the softening point is too low (<300°C), the glass powder will melt too early, blocking the escape channel of the resin decomposition gas, causing the board to bubble and swell; the silica content in the glass powder is 35%-40%, the boron oxide content is 25%-30%, the zinc oxide content is 15%-20%, the Na2O and K2O (alkali metal oxide) content is 10%-12%, and the aluminum oxide content is 3%-5%.

[0022] The application further provides a ship fireproof rock wool board, and the structure of the ship fireproof rock wool board is sequentially arranged from top to bottom as an aluminum alloy foil layer, a semi-cured reinforced prepreg layer, a surface treated basalt wool board, a semi-cured reinforced prepreg layer and an aluminum alloy foil layer.

[0023] Compared with the prior art, the application has the following beneficial effects:

[0024] 1、The application realizes the leap from passive thermal insulation to active chemical fire extinguishing by introducing the organic phosphorus hetero-fused derivative and cyclotriphosphazene synergistic system into the resin matrix; when heated, the active phosphorus-containing radicals rapidly enter the gas phase area, efficiently capture the key radicals that maintain the combustion chain reaction, and instantaneously cut off the flame propagation path; at the same time, the nitrogen-phosphorus synergistic effect promotes the rapid dehydration of the matrix into carbon and the release of inert gas, significantly reduces the smoke and toxic gas concentration, effectively solves the hidden danger of flammability and high toxicity of traditional boards, and significantly improves the safety of escape in ship fire.

[0025] 2、In view of the defect that rock wool is prone to shrinkage and pulverization at high temperature, the application constructs a self-ceramization skeleton system based on low-melting-point glass powder and calcined kaolin; the fluxing components undergo liquid phase transformation at high temperature, tightly bond the kaolin skeleton and rock wool fibers, and in-situ convert into a hard and dense ceramic composite shell; the high-temperature adhesive mechanism effectively compensates for the volume loss caused by organic ablation, gives the board excellent dimensional stability, ensures that it does not crack or collapse under the impact of intense fire, and maintains excellent thermal insulation integrity.

[0026] 3、In view of the erosion of the interface in the high-humidity salt spray environment of the ocean, the application selects a titanium acid ester coupling agent with better hydrolysis resistance to deeply activate the core material. The long-chain structure of the titanium acid ester can form a stable coordination bond with the fiber surface and construct a hydrophobic barrier, effectively blocking the attack of water molecules and chloride ions; the application overcomes the drawbacks of traditional adhesive layers that are prone to hydrolysis and peeling in a humid environment, ensures that the board still maintains a high strength retention rate and a low water absorption rate after long-term service, and significantly prolongs the service life of the material in harsh sea conditions.

[0027] 4、The application adopts a high-pressure pulse spraying and gradient curing synergistic process to solve the problem of difficult control of internal defects in thick boards. High-pressure pulse deeply implants active components into the deep layer of fibers, eliminating the hidden danger of weak skin-core bonding force; gradient temperature and pressure control realizes full degassing and densification during the rheological window period of the resin, avoiding high-temperature board explosion; the vertical tensile strength and compression bearing capacity of the board are improved, so that it can withstand the continuous low-frequency vibration during ship navigation without delamination or fatigue failure, realizing the dual reinforcement of structure and function.

[0028] 5、The application selects linear phenolic epoxy resin with extremely high heat resistance and aromatic amine curing agent to construct a rigid network with high crosslinking density. The system is rich in benzene ring structure, greatly improves the glass transition temperature of the material, and delays the heat transfer in the initial stage of fire. At the same time, the high-temperature pyrolysis of the matrix can generate a high-yield carbon skeleton, which is supported by inorganic fillers, greatly enhances the mechanical strength of the carbon layer, effectively prevents the structure from collapsing due to the premature softening and flowing of the matrix, and ensures the reliability at extremely high temperature. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 The preparation method flow chart of the fireproof rock wool board for ships of the application. DETAILED DESCRIPTION

[0030] The technical solutions in the embodiments of the application will be clearly and completely described below with reference to the drawings in 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.

[0031] Please refer to Figure 1 The application provides a fireproof rock wool board for ships and a preparation method thereof, and the technical solutions are as follows:

[0032] Example 1 99.8 parts of linear phenol aldehyde epoxy resin were put into a four-port reaction kettle equipped with a mechanical stirrer, a precision thermometer, a nitrogen inlet and a reflux condenser; under a stirring speed of 100 r / min, the oil bath was heated to 110-120°C, and vacuum dehydration was performed under a vacuum degree of less than -0.098 MPa for 1.0-1.5 h until the water content in the resin was less than 0.03% to prevent the generation of bubbles in subsequent curing; then, the vacuum was released, dry nitrogen was introduced for protection, and the temperature of the reaction kettle was reduced to 90°C; at this temperature, 20.3 parts of microencapsulated 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide as a primary extinguishing agent, 14.5 parts of halogen-free flame-retardant synergist hexaphenoxycyclotriphosphazene and 30.1 parts of borosilicate low-melting glass powder with a softening point of 480°C were sequentially added to the kettle; after the addition was completed, the stirring speed was increased to 2000 r / min for high-speed shearing dispersion, and uniform mixing was maintained at 90°C for 45 min; the temperature of the reaction liquid was reduced to 75°C, 28 parts of 4,4'-diamino diphenyl sulfone as a high-temperature resistant curing agent and 19.8 parts of flaky kaolin were added to the reaction system; in order to reduce the viscosity of the system to facilitate impregnation, an appropriate amount of anhydrous butanone was added as a solvent (about 15% of the total amount of the resin), and stirring was continued at 75°C for 30 min until the curing agent was completely dissolved and the system was in a uniform suspension state; after the reaction was completed, the system was naturally cooled to room temperature, and was placed under a negative pressure of -0.09 MPa for 20 min to remove bubbles, thereby preparing a self-ceramizing active extinguishing resin slurry with a viscosity of 3500-4500 mPa·s;

[0033] In a liquid preparation tank, 100 parts of anhydrous ethanol were weighed; under a low-speed stirring state of 300 r / min, 3.5 parts of isopropyl tri(dioctyl pyrophosphato) titanate coupling agent and 2 parts of E-51 were slowly added dropwise, and stirring was performed for 30 min to make them fully dissolved, thereby preparing an interfacial activation liquid; a high-density basalt wool board with a thickness of 50 mm and a density of 159.2 kg / m³ was selected as a core material, and the average diameter of the fibers of the core material was controlled to be 4-5 μm; the basalt wool board was placed in a closed high-pressure pulse spraying chamber, an interfacial activation liquid was sprayed in an atomized form on the surface and deep fibers of the basalt wool board by using a pulse nozzle with a pressure of 0.8 MPa, and the spraying amount was controlled to be 201.0 g / m²; then, the treated basalt wool board was sent into a 105°C air-drying oven, and was dried for 15 min to completely volatilize the ethanol solvent, thereby obtaining a surface-treated basalt wool board;

[0034] Alkali-free glass fiber mesh cloth as the reinforcing framework; using a precision knife coater, the prepared self-ceramization active fire-retardant resin slurry is coated on the glass fiber mesh cloth, the knife gap is adjusted to control the resin content at 48%-52%, and a semi-cured reinforced prepreg is prepared; two pieces of hard aluminum alloy foil with a thickness of 0.05 mm and a surface treated by corona to a surface tension greater than 42 dyne / cm are selected; in the mold, the five-layer symmetric laminated assembly is carried out in the order of aluminum alloy foil-semi-cured reinforced prepreg-titanate activated rock wool board-semi-cured reinforced prepreg-aluminum alloy foil; during the assembly process, micro-pressure needs to be applied to each layer to ensure that there is no obvious air inclusion between the layers.

[0035] The assembled laminated plate blank is sent into a hot press with multi-stage temperature and pressure control functions, and a gradient curing program is strictly implemented; the first stage (exhaust and wetting zone): the temperature is set to 120℃, the pressure is set to 0.2MPa, and the holding time is 20min; the resin viscosity is reduced from 3500-4500mPa·s to 150-300mPa·s, and the rock wool surface is penetrated under low pressure, while the interlayer volatile components are discharged; the second stage (crosslinking and forming zone): the temperature is raised to 180℃, the pressure is increased to 0.40MPa, and the holding time is 63min; a high-temperature-resistant steel limiting pad with a height of 50mm (consistent with the thickness of the finished product) is placed around the mold. When the hot press pressure plate contacts the limiting block, it stops, and the pressure displayed at this time is mainly borne by the limiting block; this stage initiates the ring-opening addition reaction of epoxy groups and amine groups to build a three-dimensional network with high crosslinking density, and high pressure forces the low-melting-point glass powder to tightly engage with the rock wool fibers; the third stage (stress relief zone): the pressure remains unchanged, the temperature is reduced to 60℃, and the mold is opened after 30min of holding; the internal stress generated due to the difference in thermal expansion coefficient is eliminated by slow cooling, and finally the finished product is obtained.

[0036] Examples 2-6 are different from Example 1 in that the following multi-factor variables are adjusted, as shown in Table 1; the parts are all mass parts.

[0037] Table 1 Preparation method of fireproof rock wool board for ships

[0038] ;

[0039] .

[0040] Comparative Examples 1-8 are different from Example 1 in that the following preparation conditions are changed, as shown below.

[0041] In Comparative Example 1, the amount of linear phenolic epoxy resin is increased to 130 parts, and the corresponding mass ratio of the curing agent is increased.

[0042] In Comparative Example 2, the amount of linear phenolic epoxy resin is reduced to 70 parts.

[0043] Comparative Example 3 does not add microencapsulated DOPO derivatives, and an equal amount of ordinary silica powder is used instead.

[0044] Comparative Example 4 does not add calcined kaolin, but instead an equal amount of ordinary calcium carbonate filler is added.

[0045] Comparative Example 5 does not add low-melting glass powder.

[0046] Comparative Example 6 replaces the titanate coupling agent with an equal amount of ordinary amino silane (KH-550).

[0047] Comparative Example 7 only uses surface spraying for the interfacial activation liquid, without high-pressure pulses, but the spraying amount is kept consistent.

[0048] Comparative Example 8 reduces the second-stage forming pressure from 1.5 MPa to 0.1 MPa of contact pressure.

[0049] Test Example 1

[0050] The fire safety and smoke toxicity tests were conducted on the fireproof rock wool boards for ships prepared in the examples and comparative examples, mainly including non-combustibility test, smoke toxicity test, and limiting oxygen index test.

[0051] The non-combustibility test refers to GB / T5464-2010, and the sample is placed in a tube furnace at 750°C. The average temperature rise in the furnace (ΔT), mass loss rate (Δm), and continuous combustion time (t f ) during the test are tested. This is the key to determining whether the material meets the A-level non-combustibility.

[0052] The smoke toxicity test refers to GB / T8627-2007, which measures the optical density of the material under specific combustion conditions and calculates the smoke density rating (SDR). The lower the SDR value, the smaller the smoke emission, and the higher the safety of escape.

[0053] The limiting oxygen index test (LOI) refers to GB / T2406.2-2009, which measures the minimum oxygen concentration required to maintain combustion in a mixture of oxygen and nitrogen gas. The higher the LOI, the better the flame retardancy. The final test results are summarized in Table 2.

[0054] Table 2 Fire safety and smoke toxicity test results of Examples 1-5 and Comparative Examples 1, 3, and 8

[0055]

[0056] As can be seen from the data in Table 2, Examples 1-5 all successfully passed the stringent Class A non-combustibility test standard. Examples 3 and 4, with the lowest total amount of organic matter, had the smallest fire load, the best performance in terms of temperature rise and mass loss rate in the furnace, and the highest oxygen index, indicating that reducing the amount of organic binder is crucial to improving fire performance; although the amount of resin in Example 5 was increased, resulting in a slight increase in temperature rise and smoke emission compared to the standard group, it was still within the acceptable range; this proves that the nitrogen-phosphorus-titanium synergistic flame retardant system in the present application has strong suppression ability, and even in the case of slightly higher organic content, it can effectively inhibit combustion through chemical blocking.

[0057] The excessive amount of resin in Comparative Example 1 resulted in overall failure, and resin is an organic polymer that is essentially a fuel; when the resin content exceeds a critical value, the endothermic / dilution effect of the flame retardant cannot offset the exothermic effect of the resin combustion; excessive epoxy resin decomposes violently at 750°C, releasing a large amount of volatile flammable gases such as alkanes and aromatic hydrocarbon fragments, resulting in a sharp loss of control of the furnace temperature and a large amount of black smoke-free carbon produced by incomplete combustion, which is directly judged as non-Class A material. The LOI of Comparative Example 3 decreased significantly from 39.2% in Example 1 to 31.4%, and the duration of sustained combustion was extended to 9.5s, close to the unqualified edge; the microencapsulated DOPO derivative used in the comparative example mainly plays a gas-phase flame-retardant role, releasing PO· free radicals when it decomposes under heat, which can quickly capture highly active H· and OH· free radicals in the flame chain reaction like scavengers; Comparative Example 3 removes this component, losing the active fire extinguishing ability to cut off the combustion chain. Although the remaining phosphazene and filler can play a condensed-phase charring flame-retardant role, they cannot inhibit flame propagation in the gas phase, so once the material is ignited, it is more difficult for the flame to self-extinguish, resulting in a significant decrease in the oxygen index; hexaphenoxy cyclotriphosphazene plays a dual role as a charring foaming agent and a smoke suppressant in this system, and the nitrogen element contained in it releases inert gas N2 at high temperatures, causing the molten resin to expand and form a porous carbon layer; the phosphorus element promotes the dehydration and crosslinking of the resin to form carbon; without this component, the resin in the comparative example cannot form a dense and fluffy expanded carbon layer to encapsulate the internal decomposition products. A large amount of incompletely burned organic particulate smoke directly escapes into the air, resulting in a sharp increase in smoke emission, and the lack of thermal insulation protection of the expanded carbon layer also slightly increases the temperature rise in the furnace.

[0058] Test Example 2

[0059] The ship fireproof rock wool boards of Example 3, Example 4, and Comparative Examples 2, 6-7 were subjected to physical and mechanical and weather resistance tests; the tensile strength perpendicular to the board surface, salt spray aging resistance, and water absorption were tested;

[0060] The tensile strength perpendicular to the panel surface was tested according to EN 1607:2013, the sample was bonded between two rigid metal plates, a tensile load was applied in the perpendicular direction at a constant speed of 10 mm / min until failure, the maximum load was recorded and the tensile strength (kPa) was calculated; this index directly reflects the interlaminar bonding force and the ability to resist negative wind pressure and vibration;

[0061] The salt spray aging resistance was tested according to ASTM B117-19, the sample was continuously exposed in a 35℃±2℃, 5% NaCl salt spray environment for 1000h; after taking out, it was adjusted to room temperature, dried and then its vertical tensile strength was tested according to EN 1607; ;

[0062] The water absorption rate was tested according to standard GB / T10299-2011, the sample was completely immersed in water for 24h, the mass change before and after water absorption was measured, and the water absorption per unit area (kg / m²) was calculated; the final test results are summarized in Table 3.

[0063] Table 3 Physical and mechanical test results and weather resistance

[0064]

[0065] The above test results show that although the linear phenolic epoxy resin dosage of Example 3 and Example 4 is lower than that of Example 1, the test results show that its initial vertical tensile strength is still as high as 22kPa or more, and the strength retention rate is maintained at 93% or more. Even if the total amount of adhesive is reduced, that is, the risk of poor adhesion is reduced, the titanate coupling agent can still ensure the formation of high-density chemical bonding points between inorganic fibers and organic matrix, strong chemical bonding not only provides sufficient initial strength, but also blocks the penetration channel of water molecules at the microscopic level, ensuring low water absorption and excellent aging resistance; the above results show the effectiveness of titanate interface activation and high-pressure pulse penetration on the mechanical properties and weather resistance of the fireproof rock wool board for ships.

[0066] The performance of Comparative Example 2 is lower than that of Example 3 and Example 4; the resin content of the resin of the comparative example is too low, resulting in a collapse of strength; this group is in a serious state of poor glue, and the volume of the resin matrix is insufficient to continuously coat the rock wool fibers and fill the gap between the fibers, resulting in a large number of connected pores inside, the load transmission path is interrupted, the stress is concentrated on the unbound fiber nodes, resulting in premature fracture; and the capillary siphon effect caused by the connected pores is significant, causing moisture to quickly invade the interior, destroying the material structure. The initial strength of Comparative Example 6 is comparable to that of the examples, but the strength drops sharply to 12.9 kPa after aging; the Si-O-Si bond formed by the silane coupling agent has high strength in the dry state, but in a high temperature and high humidity and salt spray environment, the Si-O bond with lower bond energy is prone to reverse hydrolysis reaction and re-break into silanol groups, thereby causing the interface between the resin layer and the rock wool fibers to gradually delaminate during the aging process, and the macroscopic performance is a significant decrease in strength, while the coordination bond and hydrophobic long chain structure formed by the titanate in the examples effectively resist the attack of water molecules; the above results prove the hydrolysis resistance advantage of titanate over silane.

[0067] The absence of high-pressure pulse process in Comparative Example 7 results in weak interfacial bonding, and only surface roller coating is used, the activation liquid does not penetrate into the deep layer of rock wool, forming a weak interfacial layer, although the fibers at a depth of about 0.5 mm on the surface layer of the rock wool board are bonded, the deep layer fibers are still in a loose state, in the vertical tensile test, the failure does not occur at the resin-fiber interface, but at the subcutaneous tissue below the surface layer of the rock wool board, i.e. cohesive failure in the substrate; the core function of the high-pressure pulse process is to implant chemical anchors into the deep layer of rock wool 3-5 mm through physical impact, and to construct a gradient composite reinforcement layer, thereby avoiding such shallow peeling, and the absence of the above process results in a decrease in mechanical property test results.

[0068] Test Example 3

[0069] The fireproof rock wool boards for ships prepared from Example 5, Example 6, Comparative Example 4, Comparative Example 5 and Comparative Example 8 were tested for high temperature resistance and load resistance; the fire resistance limit and integrity test and the compression strength test were mainly aimed at simulating the structural stability of the rock wool board under the self-weight and external load in the ship fire.

[0070] The fire resistance limit and integrity test refers to the method of GB / T 9978.1-2008, and the standard size (2440 mm x 1220 mm) rock wool board is installed on the vertical combustion furnace frame; according to the standard temperature rising curve (ISO 834), heating for 60 min (furnace temperature rises to about 945℃); the average temperature rise on the back fire surface needs to be ≤140℃, the high temperature line shrinkage rate is the size change of the board in length and width direction after cooling, the lower the shrinkage rate, the more dense the structure, the stronger the ability to prevent fire from spreading; the integrity evaluation is to observe whether there is flame penetration, whether the cotton layer collapses or seriously peels off during the test.

[0071] The compressive strength was tested according to the standard GB / T 13480-2014, the sample was compressed at room temperature with a constant rate, and the compressive stress at 10% relative deformation was recorded. This index reflects the crosslinking density and mechanical load resistance of the board. The final test index is shown in Table 4.

[0072] Table 4 Test results of high temperature resistance and load resistance

[0073]

[0074] Table 4 test data shows that although examples 5 and 6 use a higher resin content, resulting in an increase in the heat of combustion, the test results show that the backfire surface temperature rise is still lower than the standard limit, and the high temperature linear shrinkage is controlled within 1.2%, which is much better than the national standard requirement of 2.0%. The above test results are mainly due to the high content of ceramic filler system. On the basis of high resin content, the proportion of low melting point glass powder and calcined kaolin is increased. The heat generated by the combustion of organic resin promotes the rapid melting of glass powder, quickly bonds the kaolin skeleton with rock wool fibers, forming a thicker and denser ceramic insulation layer. This layer of composite ceramic shell effectively compensates for the volume loss caused by the decomposition of organic matter, achieving zero shrinkage or even micro-expansion effect.

[0075] The absence of the ceramic framework - calcined kaolin in Comparative Example 4 resulted in severe shrinkage, over-standard temperature rise on the back face, and through cracks on the board; at high temperature of 900°C, the low melting point glass powder completely liquefied with extremely low viscosity, and due to the lack of rigid framework support of high melting point (>1700°C) calcined kaolin, the liquid phase glass could not maintain its shape and would flow and drip under the action of gravity, and after the rock wool fibers lost the binding of the binder, sintering shrinkage occurred, resulting in a decrease in the overall size of the board and the generation of wide cracks, and the direct penetration of the flame through the cracks led to the loss of control of the back face temperature. The integrity of Comparative Example 5 was rated as powdering and falling off, and the cotton layer lost strength and collapsed; this group only contained calcined kaolin, and the melting point of kaolin itself was extremely high, and it was in a solid phase at the temperature of the ship fire (about 945°C) and could not melt, and due to the lack of liquid phase bridging provided by the low melting point glass powder, after the organic resin was decomposed and carbonized, there was no adhesion between the kaolin powder and the rock wool fibers, and the surface carbon layer would be peeled off in powder form under the action of air flow disturbance or slight vibration, and the internal rock wool would be directly exposed to the flame, rapidly powdered and lost structural support. The insufficient curing pressure of Comparative Example 8 led to a double decrease in structural strength and fire resistance, and bulging deformation occurred during the fire resistance test; the low pressure led to insufficient density inside the board, and there were a large number of macroscopic pores between the fibers and the resin, which directly weakened the compression bearing capacity; and during the rapid heating stage of the fire resistance test, the gas enclosed in the pores rapidly expanded; due to the loose resin crosslinked network, the internal pressure could not be resisted, leading to the surface of the board to be peeled off or bulged in an explosive manner, which destroyed the continuity of the insulation layer and led to the invasion of hot gas into the interior, accelerating the structural collapse.

[0076] Although embodiments of the present application have been shown and described, it is to be understood that various modifications, substitutions, replacements and changes can be made to these embodiments without departing from the principles and spirit of the present application, and the scope of the present application is defined by the appended claims and their equivalents.

Claims

1. A method for preparing fireproof rock wool board for ships, characterized in that, The preparation method is as follows: 99.8 parts of linear phenolic epoxy resin are added to a four-necked reactor. Under inert gas protection, 20.3 parts of microencapsulated fire extinguishing agent, 14.5 parts of flame retardant synergist hexaphenoxycyclotriphosphazene, and 30.1 parts of low-melting-point glass powder are added. After high-speed shear dispersion, 28.0 parts of high-temperature resistant curing agent 4,4'-diaminodiphenyl sulfone, 19.8 parts of ceramicized skeleton filler calcined kaolin, and solvent are added. After degassing, ceramicized resin slurry is obtained. The microencapsulated fire extinguishing agent is microencapsulated 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide. Surface-treated basalt wool boards are obtained by surface treatment of basalt wool boards. The surface treatment is as follows: 100 parts of anhydrous ethanol are weighed in a mixing tank; 3.5 parts of isopropyl tris(dioctyl pyrophosphate oxy) titanate coupling agent and 2 parts of epoxy resin E-51 are slowly added dropwise under low-speed stirring at 300 r / min, and stirred for 30 min to fully dissolve them, thus preparing an interface activation solution; a high-density basalt wool board with a thickness of 50 mm and a density of 159.2 kg / m³ is selected as the core material, and the average diameter of the fibers in the core material is controlled at 4-5 μm. The rock wool board was placed in a sealed high-pressure pulse spraying chamber. Using a pulse nozzle with a pressure of 0.8 MPa, the interface activation liquid was sprayed on both sides of the rock wool board surface and deep fibers in the form of atomization. The spraying amount was controlled at 201.0 g / m². Then, the treated rock wool board was sent to a forced-air drying oven at 105℃ and dried for 15 minutes to completely evaporate the ethanol solvent. The self-ceramicized resin slurry is coated onto an alkali-free glass fiber mesh to obtain a semi-cured reinforced prepreg. The fireproof rock wool board for ships is obtained by laminating surface-treated hard aluminum alloy foil, surface-treated basalt rock wool board, and semi-cured reinforced prepreg, followed by gradient curing. The gradient curing process is as follows: The first stage is the venting and wetting zone: the temperature is set at 120℃, the pressure is set at 0.2MPa, and the holding time is 20min; during this stage, the resin viscosity decreases from 3500-4500mPa·s to 150-300mPa·s, penetrating into the surface layer of the rock wool under low pressure; The second stage is the crosslinking and molding zone: the temperature is raised to 180℃, the pressure is increased to 0.40MPa, and the holding time is 63min. Place high-temperature resistant steel limit pads with a height of 50mm around the mold; the third stage is the stress relief zone: keep the pressure constant, reduce the temperature to 60℃, keep it at that temperature for 30 minutes, and then open the mold; the penetration depth is 3-5mm.

2. The method for preparing a fireproof rock wool board for ships according to claim 1, characterized in that, The microencapsulated fire extinguishing agent is prepared by preparing a melamine-formaldehyde prepolymer solution; preparing a core material dispersion containing a styrene-maleic anhydride copolymer hydrolysate; adding the melamine-formaldehyde prepolymer solution dropwise into the core material dispersion; and obtaining the product through in-situ coating, curing, and post-treatment.

3. The method for preparing a fireproof rock wool board for ships according to claim 2, characterized in that, The preparation steps of the core material dispersion are as follows: styrene-maleic anhydride copolymer is added to deionized water, an alkaline regulator is added to adjust the pH value to alkaline, and the mixture is heated and stirred to hydrolyze and dissolve it, resulting in a clear SMA hydrolysate; the 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide powder is added to the SMA hydrolysate for shear dispersion, and then an acidic regulator is added to adjust the pH value to acidic.

4. The method for preparing a fireproof rock wool board for ships according to claim 2, characterized in that, The in-situ coating and curing process involves heating the mixed system and continuously stirring the reaction; the post-treatment includes filtration, warm water washing, and drying.

5. A fireproof rock wool board for ships, characterized in that, The fireproof rock wool board for ships is obtained by the preparation method described in any one of claims 1-4; the structure of the fireproof rock wool board for ships, from top to bottom, consists of an aluminum alloy foil layer, a semi-cured reinforced prepreg layer, a surface-treated basalt rock wool board, a semi-cured reinforced prepreg layer, and an aluminum alloy foil layer.

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