Flame-retardant materials, polycarbonate composites and their preparation methods

Abstract

This invention discloses a flame-retardant material, a polycarbonate composite material, and a preparation method thereof, belonging to the field of flame-retardant technology. The flame-retardant material comprises a sulfonate flame retardant and a glass coating layer, wherein the glass coating layer covers the exterior of the sulfonate flame retardant; wherein the softening point temperature of the glass coating layer is 350℃-450℃. In this flame-retardant material, the sulfonate flame retardant promotes the formation of a char layer in the polycarbonate, and the molten glass coating layer stabilizes and strengthens the char layer, thereby improving the flame-retardant performance of the polycarbonate composite material. The glass coating layer also prevents moisture from contacting the sulfonate flame retardant, avoiding moisture absorption and dampness during storage.

Description

Technical Field

[0001] This invention relates to the field of flame retardant technology, and particularly to flame retardant materials, polycarbonate composite materials, and preparation methods. Background Technology

[0002] Polycarbonate (PC) has excellent heat resistance, impact resistance, dimensional stability and electrical insulation properties, and is commonly used in the manufacture of electrical products.

[0003] Because polycarbonate has poor flame retardant properties, it is usually mixed with sulfonate flame retardants to prepare polycarbonate composite materials with better flame retardant properties.

[0004] However, the existing technology involves simply mixing polycarbonate and sulfonate flame retardants, resulting in extremely low addition levels of sulfonate flame retardants to polycarbonate. This often leads to uneven dispersion of the flame retardant, resulting in poor flame retardant performance for thin-walled components. Furthermore, sulfonate flame retardants have poor water resistance and are prone to moisture absorption. All of these factors contribute to the deterioration of the flame retardant properties of polycarbonate composites. Summary of the Invention

[0005] In view of this, the present invention provides flame-retardant materials, polycarbonate composite materials and preparation methods, which can solve the technical problems existing in related technologies.

[0006] Specifically, the following technical solutions are included:

[0007] On the one hand, a flame retardant material is provided, the flame retardant material comprising: a sulfonate flame retardant and a glass coating layer, wherein the glass coating layer covers the outside of the sulfonate flame retardant;

[0008] The softening point temperature of the glass cladding layer is 350℃-450℃.

[0009] In some possible implementations, the sulfonate flame retardant includes at least one of potassium perfluorobutyl sulfonate, potassium diphenyl sulfonate, and sodium 2,4,5-trichlorobenzenesulfonate.

[0010] In some possible implementations, the particle size of the sulfonate flame retardant is 1 μm-5 μm, and / or the particle size of the flame retardant material is 10 μm-50 μm.

[0011] In some possible implementations, the raw materials for preparing the flame retardant material comprise the following components by mass percentage:

[0012] Glass preparation raw materials 45%-75%, sulfonate flame retardant 10%-35%, alkaline co-solvent 15%-20%;

[0013] The softening point temperature of the glass preparation raw material is 350℃-450℃.

[0014] In some possible implementations, the alkaline co-solvent is selected from NaOH solution and / or KOH solution with a concentration of 3 mol / L to 6 mol / L.

[0015] On the other hand, a method for preparing a flame-retardant material is provided, wherein the flame-retardant material is as described in any of the above descriptions;

[0016] The method for preparing the flame-retardant material includes:

[0017] The raw materials for preparing the flame retardant material are subjected to cold sintering treatment to obtain a glass-flame retardant composite, wherein the glass-flame retardant composite includes a sulfonate flame retardant and a glass layer covering the outside of the sulfonate flame retardant;

[0018] The glass-flame retardant composite is ground and purified to obtain the flame retardant material.

[0019] In some possible implementations, the cold sintering treatment of the raw materials for preparing the flame retardant material to obtain a glass-flame retardant composite includes:

[0020] Under a pressure of 300MPa-400MPa, the raw materials for preparing the flame retardant material are heated to 130℃-180℃ at a set heating rate, and after heat preservation and pressure treatment, the glass-flame retardant composite is obtained.

[0021] In another aspect, a polycarbonate composite material is provided, the polycarbonate composite material comprising the following components in weight percentages:

[0022] The composition includes 0.1%-2% of any of the above flame retardant materials, 91%-99.6% of polycarbonate resin, 0-5% of toughening agent, and 0.2%-2% of additives.

[0023] In some possible implementations, the toughening agent is selected from at least one of methyl methacrylate-silicone-acrylate terpolymer, methyl methacrylate-butadiene-styrene terpolymer, ethylene-1-octene copolymer, ethylene-methyl acrylate-glycidyl methacrylate terpolymer, maleic anhydride-grafted ethylene-propylene diene monomer (EPDM) rubber, maleic anhydride-grafted ethylene-1-octene copolymer, and chlorinated polyethylene.

[0024] In some possible implementations, the additive is selected from at least one of antioxidants and lubricants.

[0025] In another aspect, a method for preparing a polycarbonate composite material is provided, wherein the polycarbonate composite material is as described in any of the above descriptions;

[0026] The method for preparing the polycarbonate composite material includes: performing injection molding or extrusion processing on each component of the uniformly mixed polycarbonate composite material under a set temperature gradient to obtain the polycarbonate composite material.

[0027] In some possible implementations, the melt mass flow rate of the polycarbonate resin is 8 g / 10 min to 22 g / 10 min.

[0028] The beneficial effects of the technical solutions provided in the embodiments of the present invention include at least the following:

[0029] Firstly, by coating the sulfonate flame retardant with a glass coating, it is not only beneficial to increase the amount of flame retardant material added to the polycarbonate composite material, but also to make the flame retardant material more evenly dispersed in the polycarbonate composite material. The glass coating can also prevent moisture from contacting the sulfonate flame retardant, thus preventing the sulfonate flame retardant from absorbing water and becoming damp during storage.

[0030] Secondly, since the softening point of the glass cladding layer is relatively low (350℃-450℃), when this flame-retardant material is used in polycarbonate composites, the low softening point of the glass cladding layer melts upon heating, and the sulfonate flame retardant promotes the cross-linking of polycarbonate into char. The molten glass cladding layer not only forms a dense liquid glass film covering the polycarbonate surface, providing excellent heat and oxygen insulation, but also contains silicon with low surface free energy, allowing it to migrate to the polycarbonate surface and form a stable silicon-carbon compound or a continuous silica protective layer, thus stabilizing and strengthening the char layer. Therefore, the sulfonate flame retardant in this flame-retardant material promotes the formation of a char layer in polycarbonate, and the molten glass cladding layer stabilizes and strengthens the char layer, effectively preventing heat transfer and the release of flammable gases, significantly improving the flame-retardant performance of polycarbonate composites.

[0031] Third, the sulfonate flame retardant has a glass coating layer on the outside. Although its softening temperature is low, the glass coating layer itself has the strength and hardness of ceramics, which allows it to withstand the high temperature and strong shear conditions during the extrusion process of polycarbonate composite materials. This ensures that the glass coating layer of the flame retardant material is not damaged during the process, thereby playing a barrier role in polycarbonate composite materials and improving the flame retardant stability of polycarbonate composite materials.

[0032] Fourth, the synergistic flame-retardant performance between the glass coating and the sulfonate flame retardant is excellent and outstanding, and the flame-retardant mechanism is diversified, which enables the prepared flame-retardant material to achieve a flame-retardant level of 1.0mm V-0 and a flame-retardant level of 1.0mm WFI960℃. Detailed Implementation

[0033] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0034] On one hand, embodiments of the present invention provide a flame retardant material comprising: a sulfonate flame retardant and a glass coating layer, wherein the glass coating layer covers the outside of the sulfonate flame retardant; wherein the softening point temperature, also known as the melting temperature, of the glass coating layer is 350℃-450℃.

[0035] The flame-retardant material provided in this embodiment of the invention has at least the following advantages:

[0036] Firstly, by coating the sulfonate flame retardant with a glass coating, it is not only beneficial to increase the amount of flame retardant material added to the polycarbonate composite material, but also to make the flame retardant material more evenly dispersed in the polycarbonate composite material. The glass coating can also prevent moisture from contacting the sulfonate flame retardant, thus preventing the sulfonate flame retardant from absorbing water and becoming damp during storage.

[0037] Secondly, since the softening point of the glass cladding layer is relatively low (350℃-450℃), when this flame-retardant material is used in polycarbonate composites, the low softening point of the glass cladding layer melts upon heating, and the sulfonate flame retardant promotes the cross-linking of polycarbonate into char. The molten glass cladding layer not only forms a dense liquid glass film covering the polycarbonate surface, providing excellent heat and oxygen insulation, but also contains silicon with low surface free energy, allowing it to migrate to the polycarbonate surface and form a stable silicon-carbon compound or a continuous silica protective layer, thus stabilizing and strengthening the char layer. Therefore, the sulfonate flame retardant in this flame-retardant material promotes the formation of a char layer in polycarbonate, and the molten glass cladding layer stabilizes and strengthens the char layer, effectively preventing heat transfer and the release of flammable gases, significantly improving the flame-retardant performance of polycarbonate composites.

[0038] Third, the sulfonate flame retardant has a glass coating layer on the outside. Although its softening temperature is low, the glass coating layer itself has the strength and hardness of ceramics, which allows it to withstand the high temperature and strong shear conditions during the extrusion process of polycarbonate composite materials. This ensures that the glass coating layer of the flame retardant material is not damaged during the process, thereby playing a barrier role in polycarbonate composite materials and improving the flame retardant stability of polycarbonate composite materials.

[0039] Fourth, the synergistic flame-retardant performance between the glass coating and the sulfonate flame retardant is excellent and outstanding, and the flame-retardant mechanism is diversified, which enables the prepared flame-retardant material to achieve a flame-retardant level of 1.0mm V-0 and a flame-retardant level of 1.0mm WFI960℃.

[0040] In this embodiment of the invention, the softening point temperature of the glass cladding layer includes, but is not limited to, 350°C, 360°C, 370°C, 380°C, 390°C, 400°C, 410°C, 420°C, 430°C, 440°C, and 450°C.

[0041] Some suitable sulfonate flame retardants include at least one of potassium nonafluoro-1-butanesulfonate (PPFBS), potassium 3-(phenylsulfonyl)benzenesulfonate (KSS), and sodium 2,4,5-trichlorobenzenesulfonate (STB). All of these sulfonate flame retardants are suitable for polycarbonate composites and impart excellent flame retardant properties.

[0042] In some examples, the particle size of the sulfonate flame retardant is 1μm-5μm, including but not limited to: 1μm, 2μm, 3μm, 4μm, 5μm, etc.

[0043] In some examples, the particle size of the flame retardant material is 10μm-50μm, including but not limited to: 10μm, 15μm, 20μm, 25μm, 30μm, 35μm, 40μm, 45μm, 50μm, etc.

[0044] In some examples, the raw materials for preparing the flame retardant material include the following components in the following mass percentages: 45%-75% glass preparation raw materials, 10%-35% sulfonate flame retardant, and 15%-20% alkaline co-solvent; wherein the softening point temperature of the glass preparation raw materials is 350℃-450℃.

[0045] For glass preparation raw materials, it refers to raw materials that can be sintered to form glass. In this embodiment of the invention, a glass coating layer with a low softening point temperature is formed by using glass preparation raw materials with a softening point temperature of 350℃-450℃.

[0046] Through the synergistic effect of the components in the raw materials for flame retardant preparation, a glass coating layer can be formed on the surface of the sulfonate flame retardant after sintering.

[0047] For example, the glass preparation raw material includes at least a silicon dioxide component, which may be at least one of SiO2.B2O3, SiO2.ZnO and SiO2.P2O5, and the mass of the silicon dioxide component is at least 50% of the mass of the glass preparation raw material, and may further be 70%, 80%, 90% of the mass of the glass preparation raw material, etc.

[0048] For example, the alkaline co-solvent is selected from NaOH solution and / or KOH solution with a concentration of 3 mol / L to 6 mol / L.

[0049] The use of the aforementioned alkaline co-solvent serves two purposes. First, it enhances the dissolution effect of the sulfonate flame retardant, facilitating the uniform mixing of the sulfonate co-solvent and the glass preparation raw materials. Second, the alkaline co-solvent reacts with silica to form inorganic silicates, allowing the glass preparation raw materials to be surface-wetted and dissolved by the alkaline co-solvent.

[0050] For example, the mass percentage of glass preparation raw materials includes, but is not limited to, 45%, 46%, 47%, 48%, 49%, 50%, 51%, 52%, 53%, 54%, 55%, 56%, 57%, 58%, 59%, 60%, 61%, 62%, 63%, 64%, 65%, 66%, 67%, 68%, 69%, 70%, 71%, 72%, 73%, 74%, 75%, etc.

[0051] The mass percentage of sulfonate flame retardants includes, but is not limited to, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, 30%, 31%, 32%, 33%, 34%, and 35%.

[0052] The mass percentage of alkaline co-solvents includes, but is not limited to, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, etc.

[0053] On the other hand, embodiments of the present invention also provide a method for preparing a flame-retardant material, wherein the flame-retardant material is as described in any of the above descriptions.

[0054] The preparation method of this flame-retardant material includes: cold sintering the raw materials for preparing the flame-retardant material to obtain a glass-flame retardant composite, wherein the glass-flame retardant composite includes a sulfonate flame retardant and a glass layer coating the outside of the sulfonate flame retardant. The glass-flame retardant composite is then ground and purified to obtain the flame-retardant material.

[0055] The raw materials for preparing this flame-retardant material include the following components by mass percentage: 45%-75% glass preparation raw materials, 10%-35% sulfonate flame retardant, and 15%-20% alkaline co-solvent; wherein the softening point temperature of the glass preparation raw materials is 350℃-450℃. For details regarding the components in the raw materials for preparing the flame-retardant material, please refer to the above description, which will not be repeated here.

[0056] Cold sintering is a novel ceramic sintering technology that densifies ceramic powder within a relatively low temperature range under the action of an intermediate liquid phase and uniaxial pressure.

[0057] The cold sintering process comprises three stages: the first stage involves the introduction of the liquid phase and particle rearrangement. Selecting a suitable liquid phase is crucial for achieving densification during cold sintering, which requires the glass preparation raw materials to possess a certain degree of solubility in the liquid phase. In this embodiment of the invention, an alkaline co-solvent is used. On one hand, sulfonates are readily soluble in alkaline co-solvents, facilitating uniform mixing of sulfonates and glass preparation raw materials. On the other hand, SiO2 is the main component of low softening temperature glass powder; SiO2 and the alkaline co-solvent can react chemically to generate inorganic silicates, thereby enabling the glass powder to be wetted and dissolved by the alkaline co-solvent surface. The alkaline co-solvent uniformly wets the sulfonate and low softening temperature glass powder mixture, forming a liquid film on its surface. The alkaline co-solvent promotes localized dissolution of sharp particle surfaces and acts as a lubricant to facilitate particle rearrangement and sliding.

[0058] The second stage is dissolution-precipitation. The solid particles partially dissolve in the alkaline co-solvent. In the initial stage of heating, the solubility of the solid particles is increased. However, as the temperature rises further, the solvent evaporates faster, and the portion of the solid particles dissolved in the liquid phase becomes supersaturated and precipitates, forming an intermediate phase, thereby strengthening the contact between particles.

[0059] In the third stage, the partially dissolved and reprecipitated intermediate phase recrystallizes as the temperature and holding time increase. Under the action of alkaline co-solvent and extremely high pressure, SiO2 promotes the breakage of silicon-oxygen bonds, forming a series of silicon-oxygen tetrahedral units in a low-polymerization state. These low-polymerization silicon-oxygen tetrahedral units gradually repolymerize as sintering progresses, and after drying and solidification, form a high-strength glass body.

[0060] This invention provides flame-retardant materials prepared using a ceramic cold sintering-pulverization process. Through cold sintering, a glass coating layer with enhanced thermal stability is applied to the surface of the sulfonate flame retardant, thereby improving its thermal stability. The glass-flame retardant composite is then ground and purified to remove unbound sulfonate flame retardants, unreacted glass preparation materials, and excess alkaline co-solvents, resulting in a high-purity flame-retardant material. This preparation method offers advantages such as simple operation, high production efficiency, low energy consumption, and safety with no pollution.

[0061] In some examples, the raw materials for preparing flame retardant materials are subjected to cold sintering to obtain a glass-flame retardant composite, including: heating the raw materials for preparing flame retardant materials to 130℃-180℃ at a set heating rate under a pressure of 300MPa-400MPa, and then performing heat preservation and pressure holding treatment to obtain the glass-flame retardant composite.

[0062] By sintering the raw materials for flame retardant materials at a pressure of 300MPa-400MPa and a low temperature of 130℃-180℃, a glass coating layer can be stably formed on the surface of the sulfonate flame retardant. This avoids problems such as performance degradation and oxidative decomposition of the sulfonate flame retardant caused by high-temperature sintering.

[0063] The sintering temperatures include, but are not limited to, 130℃, 140℃, 150℃, 160℃, 170℃, and 180℃, and the sintering pressures include, but are not limited to, 300MPa, 310MPa, 320MPa, 330MPa, 340MPa, 350MPa, 360MPa, 370MPa, 380MPa, 390MPa, and 400MPa.

[0064] The embodiments of the present invention are based on the preparation of flame retardant materials by ceramic cold sintering-ball milling process. The present invention prepares a ceramic body doped with sulfonate by cold sintering process, and then crushes and grinds the ceramic body to a particle size of 10-50μm to obtain a sulfonate flame retardant with a transparent glass layer on the surface.

[0065] In some examples, the heating rate can be 8℃ / min-12℃ / min, including but not limited to 8℃ / min, 9℃ / min, 10℃ / min, 11℃ / min, 12℃ / min, etc., so that the temperature rise is stable and controllable.

[0066] In some implementations, embodiments of the present invention provide a method for preparing a flame-retardant material, the preparation steps of which are as follows:

[0067] Step 1, mixing, includes: adding alkaline co-solvent to the mixed powder of sulfonate flame retardant and glass preparation raw materials, grinding evenly, and preparing a paste.

[0068] Step 2, cold sintering, includes: placing the paste in a steel mold, applying pressure of 300MPa-400MPa to the steel mold using a uniaxial press, and heating the inside of the steel mold to 130℃-180℃ at a heating rate of 10℃ / min using heaters on the outer ring of the steel mold (for example, by arranging heaters on the outer wall of the steel mold), holding the temperature and pressure for 20min-30min to obtain the glass-flame retardant composite.

[0069] Step 3, grinding, includes: mechanically crushing the glass-flame retardant composite and grinding it in a ball mill to a particle size of 10μm-50μm to obtain product powder.

[0070] Step 4, washing with water, includes: washing the above product powder with distilled water until pH=7, and then filtering to obtain a filter cake.

[0071] Step 5, drying, which includes: placing the filter cake in an oven and drying it at 120℃-140℃ for 8-10 hours to obtain a flame retardant material with the desired composition.

[0072] On the other hand, embodiments of the present invention also provide a polycarbonate composite material comprising the following components in weight percentages: 0.1%-2% of any of the above flame retardant materials, 91%-99.6% of polycarbonate resin, 0-5% of toughening agent, and 0.2%-2% of additives.

[0073] For example, the mass percentage of flame-retardant materials includes, but is not limited to: 0.1%, 0.11%, 0.12%, 0.13%, 0.14%, 0.15%, 0.16%, 0.17%, 0.18%, 0.19%, 0.2%, etc. The mass percentage of polycarbonate resin includes, but is not limited to: 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, 99.1%, 99.2%, 99.3%, 99.4%, 99.5%, 99.6%, etc. The toughening agent's mass percentage includes, but is not limited to: 0.1%, 0.15%, 0.18%, 0.2%, 0.25%, 0.3%, 0.35%, 0.4%, 0.45%, 0.5%, 0.55%, 0.6%, 0.65%, 0.7%, 0.75%, 0.8%, 0.85%, 0.9%, 0.95%, etc. The mass percentage of the additives includes, but is not limited to: 0.2%, 0.25%, 0.3%, 0.35%, 0.4%, 0.45%, 0.5%, 0.55%, 0.6%, 0.65%, 0.7%, 0.75%, 0.8%, 0.85%, 0.9%, 0.95%, 1%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, 1.6%, 1.7%, 1.8%, 1.9%, 2%, etc.

[0074] Polycarbonate resin can give polycarbonate composites good mechanical strength and electrical insulation properties; toughening agents can improve the overall toughness of polycarbonate composites; flame retardants can give polycarbonate composites flame retardant properties; lubricants can reduce the friction between molecules inside polycarbonate, improve its processing performance, and increase production efficiency; antioxidants can extend the service life of polycarbonate composites.

[0075] The polycarbonate composite material provided in this invention, under the synergistic effect of the components in the above-mentioned mass ratio, exhibits excellent heat resistance, impact resistance, dimensional stability, and electrical insulation properties. Using the aforementioned flame-retardant material, the polycarbonate composite material can be endowed with excellent flame-retardant properties. The amount of flame-retardant material added is 0.1%-2%, which is relatively low, yet the flame-retardant efficiency is high. This overcomes the wall thickness limitation, and also provides excellent flame-retardant effects for thin-walled polycarbonate parts.

[0076] In addition, since the glass cladding layer is transparent glass, it does not affect the light transmittance of the system, resulting in the polycarbonate composite material having good light transmittance.

[0077] In some examples, the melt mass flow rate of the polycarbonate resin is 8 g / 10 min to 22 g / 10 min, which is advantageous for preparing polycarbonate composites by extrusion molding.

[0078] Some suitable toughening agents are selected from at least one of the following: methyl methacrylate-silicone-acrylate terpolymer, methyl methacrylate-butadiene-styrene terpolymer (MBS), ethylene-1-octene copolymer (POE), ethylene-methyl methacrylate-glycidyl methacrylate terpolymer (EMA-g-GMA), maleic anhydride-grafted ethylene propylene diene monomer (EPDM-g-MAH), maleic anhydride-grafted ethylene-1-octene copolymer (POE-g-MAH), and chlorinated polyethylene (CPE).

[0079] In some examples, the additive is selected from at least one of antioxidants and lubricants. For example, the antioxidant is selected from at least one of antioxidant 1076, antioxidant 1010, antioxidant 168, antioxidant 626, antioxidant PEPQ, and antioxidant 412S. The lubricant is selected from at least one of pentaerythritol stearate, Arkema L-1000, and polymeric wax.

[0080] In another aspect, embodiments of the present invention also provide a method for preparing a polycarbonate composite material, wherein the polycarbonate composite material is as described above.

[0081] The preparation method of the polycarbonate composite material includes: injection molding or extrusion processing of each component contained in the uniformly mixed polycarbonate composite material under a set temperature gradient to obtain the polycarbonate composite material.

[0082] The polycarbonate composite material comprises the following components by mass percentage: 0.1%-2% of any of the above-mentioned flame retardant materials, 91%-99.6% of polycarbonate resin, 0-5% of toughening agent, and 0.2%-2% of additives. The composition of each component in the polycarbonate composite material is described above and will not be repeated here.

[0083] Through injection molding or extrusion, the components of polycarbonate composite materials can be combined into one, forming a polycarbonate composite material with a uniform texture.

[0084] Furthermore, polycarbonate composites can be granulated to form granular polycarbonate composites for easier storage and application.

[0085] For example, under a set temperature gradient, a twin-screw extruder can be used to extrude and granulate the components of a uniformly mixed polycarbonate composite material, thereby obtaining the polycarbonate composite material.

[0086] The process parameters of the twin-screw extruder can be set as follows: Zone 1 temperature 240℃-245℃, Zone 2 temperature 250℃-255℃, Zone 3 temperature 260℃-265℃, Zone 4 temperature 270℃-275℃, Zone 5 temperature 270℃-275℃, Zone 6 temperature 270℃-275℃, Zone 7 temperature 270℃-275℃, Zone 8 temperature 270℃-275℃, Zone 9 temperature 275℃-280℃, Die head temperature 285℃-290℃, and the twin-screw extruder speed is 300r / min-500r / min.

[0087] By setting the process parameters of the twin-screw extruder as described above, it is possible to ensure that the components in the polycarbonate composite material are transformed from solid particles into a uniform melt, thereby achieving rapid extrusion molding of the polycarbonate composite material.

[0088] The flame-retardant material involved in the embodiments of the present invention has a glass coating layer on the outside of its sulfonate flame retardant. Its softening point temperature is 350-450℃, that is, its melting temperature is relatively low. It also has the strength and hardness of ceramics, which allows it to withstand the high temperature and strong shear conditions during the above-mentioned extrusion process. This ensures that the glass coating layer of the flame-retardant material is not damaged in this process, thereby playing a barrier role in the polycarbonate composite material, improving the flame-retardant stability of the polycarbonate composite material, and thus solving the problem of migration and uneven dispersion of sulfonate flame retardant due to moisture absorption.

[0089] In some examples, the melt mass flow rate of the polycarbonate resin is 8 g / 10 min to 22 g / 10 min, which is advantageous for preparing polycarbonate composites by extrusion molding.

[0090] In some implementations, embodiments of the present invention provide a method for preparing a polycarbonate composite material, the preparation steps of which are as follows:

[0091] Step 1, mixing, which includes: mixing the flame retardant, polycarbonate resin, toughening agent, and additives evenly, for example, by mixing for 3-5 minutes using a high-speed mixer.

[0092] Step 2, extrusion granulation, includes: adding the mixture prepared in step 1 into the hopper of a twin-screw extruder, and then performing melt extrusion and granulation through the twin-screw extruder.

[0093] The process parameters of the twin-screw extruder are set as follows: Zone 1 temperature 240℃-245℃, Zone 2 temperature 250℃-255℃, Zone 3 temperature 260℃-265℃, Zone 4 temperature 270℃-275℃, Zone 5 temperature 270℃-275℃, Zone 6 temperature 270℃-275℃, Zone 7 temperature 270℃-275℃, Zone 8 temperature 270℃-275℃, Zone 9 temperature 275℃-280℃, Die head temperature 285℃-290℃, and the twin-screw extruder speed is 300r / min-500r / min.

[0094] Preferred embodiments of the present invention will now be described in more detail. While preferred embodiments of the present invention are described below, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Where specific techniques or conditions are not specified in the embodiments, they are performed in accordance with techniques or conditions described in the literature in the art or according to the product instructions. Reagents or instruments whose manufacturers are not specified are all commercially available conventional products. In the following embodiments, unless otherwise specified, "%" refers to weight percentage.

[0095] Example 1

[0096] This embodiment 1 provides a flame retardant material, which includes potassium perfluorobutyl sulfonate and a glass coating layer covering the outside of the potassium perfluorobutyl sulfonate.

[0097] The raw materials for preparing this flame retardant material include the following components by mass percentage:

[0098] The glass preparation materials consist of 70% SiO2.P2O5, 10% potassium perfluorobutyl sulfonate, and 20% 5 mol / L KOH solution, wherein the softening point temperature of the glass preparation materials is 350℃.

[0099] The preparation method of this flame-retardant material is as follows:

[0100] KOH solution was added to a mixture of potassium perfluorobutyl sulfonate and glass preparation raw materials, and the mixture was ground until homogeneous to obtain a paste. The paste was placed in a steel mold, and pressure of 400 MPa was applied to the mold using a uniaxial press. The outer ring heater of the mold heated the interior to 150°C at a rate of 10°C / min, and the temperature and pressure were maintained for 30 minutes to obtain a glass-flame retardant composite. The glass-flame retardant composite was mechanically pulverized and ground in a ball mill to a particle size of 10 μm to obtain a product powder. The product powder was washed with distilled water until pH=7, and then filtered to obtain a filter cake. The filter cake was placed in an oven and dried at 120°C for 10 hours to obtain the flame retardant material.

[0101] Example 2

[0102] This embodiment 2 provides a flame retardant material, which includes potassium perfluorobutyl sulfonate and a glass coating layer covering the outside of the potassium perfluorobutyl sulfonate.

[0103] The raw materials for preparing this flame retardant material include the following components by mass percentage:

[0104] The glass preparation materials consist of 55% SiO2.P2O5, 25% potassium perfluorobutyl sulfonate, and 20% 5 mol / L NaOH solution, wherein the softening point temperature of the glass preparation materials is 370℃.

[0105] The preparation method of this flame-retardant material is as follows:

[0106] NaOH solution was added to a mixture of potassium perfluorobutyl sulfonate and glass preparation raw materials, and the mixture was ground until homogeneous to obtain a paste. The paste was placed in a steel mold, and pressure of 350 MPa was applied to the mold using a uniaxial press. The outer ring heater of the mold heated the interior to 160°C at a rate of 10°C / min, and the temperature and pressure were maintained for 25 minutes to obtain a glass-flame retardant composite. The glass-flame retardant composite was mechanically pulverized and ground in a ball mill to a particle size of 20 μm to obtain a product powder. The product powder was washed with distilled water until pH=7, and then filtered to obtain a filter cake. The filter cake was placed in an oven and dried at 130°C for 9 hours to obtain the flame retardant material.

[0107] Example 3

[0108] This embodiment 3 provides a flame retardant material, which includes potassium perfluorobutyl sulfonate and a glass coating layer covering the outside of the potassium perfluorobutyl sulfonate.

[0109] The raw materials for preparing this flame retardant material include the following components by mass percentage:

[0110] The glass preparation materials consist of 50% SiO2.P2O5, 35% potassium perfluorobutyl sulfonate, and 15% 15 mol / L KOH solution, wherein the softening point temperature of the glass preparation materials is 380℃.

[0111] The preparation method of this flame-retardant material is as follows:

[0112] KOH solution was added to a mixture of potassium perfluorobutyl sulfonate and glass preparation raw materials, and the mixture was ground until homogeneous to obtain a paste. The paste was placed in a steel mold, and pressure of 380 MPa was applied to the mold using a uniaxial press. The outer ring heater of the mold heated the interior to 180°C at a rate of 10°C / min, and the temperature and pressure were maintained for 20 minutes to obtain a glass-flame retardant composite. The glass-flame retardant composite was mechanically pulverized and ground in a ball mill to a particle size of 50 μm to obtain a product powder. The product powder was washed with distilled water until pH=7, and then filtered to obtain a filter cake. The filter cake was placed in an oven and dried at 140°C for 8 hours to obtain the flame retardant material.

[0113] Example 4

[0114] The only difference from Example 1 is that the sulfonate flame retardant is replaced with potassium diphenyl sulfonate.

[0115] Example 5

[0116] The only difference from Example 2 is that the sulfonate flame retardant in this example is replaced with potassium diphenyl sulfonate.

[0117] Example 6

[0118] The only difference from Example 3 is that the sulfonate flame retardant in this example is replaced with potassium diphenyl sulfonate.

[0119] Example 7

[0120] This embodiment 7 provides a polycarbonate composite material, the raw materials for which the polycarbonate composite material is prepared include the following components in mass percentage:

[0121] The composition consists of 97% polycarbonate resin, 2% flame retardant material prepared in Example 1, 0.5% antioxidant 1076, and 0.5% pentaerythritol stearate.

[0122] The preparation method of this polycarbonate composite material is as follows:

[0123] The components of the raw materials for preparing polycarbonate composite materials are mixed evenly, melt-blended using a twin-screw extruder, and then water-cooled and hot-cut into granules to obtain granular polycarbonate composite materials. The process parameters of the twin-screw extruder are as follows: zone 1 temperature 240℃, zone 2 temperature 250℃, zone 3 temperature 260℃, zone 4 temperature 270℃, zone 5 temperature 270℃, zone 6 temperature 270℃, zone 7 temperature 270℃, zone 8 temperature 275℃, zone 9 temperature 280℃, die head temperature 290℃, and the twin-screw extruder speed is 350 r / min.

[0124] Example 8

[0125] This embodiment 8 provides a polycarbonate composite material, the raw materials for which the polycarbonate composite material is prepared include the following components in mass percentage:

[0126] 96% polycarbonate resin, 1% flame retardant material prepared in Example 2, 1.5% methyl methacrylate-silicone-acrylate terpolymer, 0.5% antioxidant 1076, and 1% pentaerythritol stearate.

[0127] The preparation method of this polycarbonate composite material is as follows:

[0128] The components of the raw materials for preparing polycarbonate composite materials are mixed evenly, melt-blended using a twin-screw extruder, and then water-cooled and hot-cut into granules to obtain granular polycarbonate composite materials. The process parameters of the twin-screw extruder are as follows: zone 1 temperature 242℃, zone 2 temperature 252℃, zone 3 temperature 265℃, zone 4 temperature 272℃, zone 5 temperature 275℃, zone 6 temperature 275℃, zone 7 temperature 275℃, zone 8 temperature 275℃, zone 9 temperature 280℃, die head temperature 290℃, and the twin-screw extruder speed is 400 r / min.

[0129] Example 9

[0130] Example 9 provides a polycarbonate composite material, the raw materials for which the polycarbonate composite material is prepared include the following components in mass percentage:

[0131] 92.9% polycarbonate resin, 0.1% flame retardant material prepared in Example 3, 5% methyl methacrylate-butadiene-styrene terpolymer, 1% antioxidant 1076, and 1% pentaerythritol stearate.

[0132] The preparation method of this polycarbonate composite material is as follows:

[0133] The components of the raw materials for preparing polycarbonate composite materials are mixed evenly, melt-blended using a twin-screw extruder, and then water-cooled and hot-cut into granules to obtain granular polycarbonate composite materials. The process parameters of the twin-screw extruder are as follows: zone 1 temperature 243℃, zone 2 temperature 255℃, zone 3 temperature 265℃, zone 4 temperature 275℃, zone 5 temperature 272℃, zone 6 temperature 272℃, zone 7 temperature 275℃, zone 8 temperature 275℃, zone 9 temperature 280℃, die head temperature 290℃, and the twin-screw extruder speed is 450 r / min.

[0134] Example 10

[0135] This embodiment 10 provides a polycarbonate composite material, the raw materials for which the polycarbonate composite material is prepared include the following components in mass percentage:

[0136] The composition includes 95.4% polycarbonate resin, 2% flame retardant material prepared in Example 4, 2% ethylene-1-octene copolymer, 0.3% antioxidant 1076, and 0.3% pentaerythritol stearate.

[0137] The preparation method of this polycarbonate composite material is as follows:

[0138] The components of the raw materials for preparing polycarbonate composite materials are mixed evenly, melt-blended using a twin-screw extruder, and then water-cooled and hot-cut into granules to obtain granular polycarbonate composite materials. The process parameters of the twin-screw extruder are as follows: zone 1 temperature 244℃, zone 2 temperature 253℃, zone 3 temperature 262℃, zone 4 temperature 271℃, zone 5 temperature 271℃, zone 6 temperature 273℃, zone 7 temperature 273℃, zone 8 temperature 273℃, zone 9 temperature 278℃, die head temperature 282℃, and the twin-screw extruder speed is 500 r / min.

[0139] Example 11

[0140] This embodiment 11 provides a polycarbonate composite material, the raw materials for which the polycarbonate composite material is prepared include the following components in mass percentage:

[0141] The composition includes 96% polycarbonate resin, 0.8% flame retardant material prepared in Example 5, 3% maleic anhydride-grafted EPDM rubber, 0.1% antioxidant 1076, and 0.1% pentaerythritol stearate.

[0142] The preparation method of this polycarbonate composite material is as follows:

[0143] The components of the raw materials for preparing polycarbonate composite materials are mixed evenly, melt-blended using a twin-screw extruder, and then water-cooled and hot-cut into granules to obtain granular polycarbonate composite materials. The process parameters of the twin-screw extruder are as follows: zone 1 temperature 242℃, zone 2 temperature 254℃, zone 3 temperature 263℃, zone 4 temperature 270℃, zone 5 temperature 270℃, zone 6 temperature 275℃, zone 7 temperature 275℃, zone 8 temperature 275℃, zone 9 temperature 276℃, die head temperature 289℃, and the twin-screw extruder speed is 420 r / min.

[0144] Example 12

[0145] This embodiment 12 provides a polycarbonate composite material, the raw materials for which the polycarbonate composite material is prepared include the following components in mass percentage:

[0146] The composition includes 96.5% polycarbonate resin, 0.1% flame retardant material prepared in Example 6, 3% chlorinated polyethylene, 0.2% antioxidant 1076, and 0.2% pentaerythritol stearate.

[0147] The preparation method of this polycarbonate composite material is as follows:

[0148] The components of the raw materials for preparing polycarbonate composite materials are mixed evenly, melt-blended using a twin-screw extruder, and then water-cooled and hot-cut into granules to obtain granular polycarbonate composite materials. The process parameters of the twin-screw extruder are as follows: zone 1 temperature 244℃, zone 2 temperature 253℃, zone 3 temperature 264℃, zone 4 temperature 274℃, zone 5 temperature 274℃, zone 6 temperature 274℃, zone 7 temperature 274℃, zone 8 temperature 274℃, zone 9 temperature 279℃, die head temperature 290℃, and twin-screw extruder speed 460 r / min.

[0149] Comparative Example 1

[0150] The only difference from Example 7 is that uncoated potassium perfluorobutyl sulfonate flame retardant was used in this comparative example.

[0151] Comparative Example 2

[0152] The only difference from Example 8 is that uncoated potassium perfluorobutyl sulfonate flame retardant was used in this comparative example.

[0153] Comparative Example 3

[0154] The only difference from Example 9 is that uncoated potassium perfluorobutyl sulfonate flame retardant was used in this comparative example.

[0155] Comparative Example 4

[0156] The only difference from Example 10 is that uncoated potassium diphenyl sulfonate flame retardant was used in this comparative example.

[0157] Comparative Example 5

[0158] The only difference from Example 11 is that uncoated potassium diphenyl sulfonate flame retardant was used in this comparative example.

[0159] Comparative Example 6

[0160] The only difference from Example 12 is that uncoated potassium diphenyl sulfonate flame retardant was used in this comparative example.

[0161] Test case

[0162] In this test example, the polycarbonate composite material particles prepared in Examples 7-12 and Comparative Examples 1-6 were injection molded into strips or templates and their physical properties were tested. The test results are shown in Table 1.

[0163] The specific test methods for the relevant performance indicators are as follows:

[0164] Notched impact strength of cantilever beam: tested according to GB / T1843;

[0165] Vertical burning performance: tested according to UL94;

[0166] Glow wire flammability index (GWFI): Tested according to GB / T16915;

[0167] Humid heat aging: Place the sample in a constant temperature and humidity test chamber, set the temperature to 75℃ and the humidity to 85%RH, and leave it for 168 hours.

[0168] Table 1

[0169]

[0170] As shown in Table 1, for polycarbonate composite materials without moisture heat aging, none of the polycarbonate composite materials with a thickness of less than 2.0 mm in Comparative Examples 1-6 could achieve the UL94 V-0 rating. Furthermore, only the 2.0 mm thickness achieved a glow wire performance at 960°C. In contrast, all thicknesses of polycarbonate composite materials in Examples 7-12 achieved the UL94 V-0 rating, and the glow wire performance also reached 960°C. This demonstrates that the coated sulfonate flame-retardant material prepared in the embodiments of this invention exhibits a synergistic flame-retardant effect between the core sulfonate flame retardant and the low-melting-point glass coating layer, resulting in a more diversified flame-retardant mechanism and a significantly improved flame-retardant capability.

[0171] As shown in Table 1, the flame retardant properties of the polycarbonate composites in Comparative Examples 1-6 all showed a significant decrease after wet heat aging treatment. This is because Comparative Examples 1-6 used uncoated sulfonate flame retardants. Sulfonates are small-molecule flame retardants with strong water absorption, which easily migrate to the surface of the polycarbonate composite under high temperature and humidity conditions, resulting in uneven dispersion of the flame retardant and thus reducing the flame retardant properties of the polycarbonate composite. In contrast, the flame retardant properties of the polycarbonate composites in Examples 7-12 remained unchanged, indicating that the glass coating layer played an excellent barrier role, significantly reducing the moisture absorption problem of the flame retardant and thus significantly improving the flame retardant stability of the polycarbonate composite.

[0172] In embodiments of the present invention, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. The term "multiple" refers to two or more unless otherwise expressly defined.

[0173] In the embodiments of this invention, the term "and / or" is merely a description of the relationship between associated objects, indicating that there can be three relationships. For example, A and / or B can represent three situations: A exists alone, A and B exist simultaneously, and B exists alone.

[0174] The above description is merely for the purpose of enabling those skilled in the art to understand the technical solutions of the present invention, and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A flame-retardant material, characterized in that, The flame retardant material includes: a sulfonate flame retardant and a glass coating layer, wherein the glass coating layer covers the outside of the sulfonate flame retardant; The softening point temperature of the glass cladding layer is 350℃-450℃. The glass cladding layer is prepared from glass preparation raw materials. The glass preparation raw materials include at least silicon dioxide. The silicon dioxide is at least one of SiO2.B2O3, SiO2.ZnO and SiO2.P2O5. The mass of the silicon dioxide is at least 50% of the mass of the glass preparation raw materials. The sulfonate flame retardant includes at least one of potassium perfluorobutyl sulfonate, potassium diphenyl sulfonate, and sodium 2,4,5-trichlorobenzenesulfonate.

2. The flame-retardant material according to claim 1, characterized in that, The sulfonate flame retardant has a particle size of 1μm-5μm, and / or the flame retardant material has a particle size of 10μm-50μm.

3. The flame-retardant material according to any one of claims 1-2, characterized in that, The raw materials for preparing the flame retardant material include the following components by mass percentage: Glass preparation raw materials 45%-75%, sulfonate flame retardant 10%-35%, alkaline co-solvent 15%-20%; The softening point temperature of the glass preparation raw material is 350℃-450℃.

4. The flame-retardant material according to claim 3, characterized in that, The alkaline co-solvent is selected from NaOH solution and / or KOH solution with a concentration of 3mol / L-6mol / L.

5. A method for preparing a flame-retardant material, characterized in that, The flame-retardant material is as described in any one of claims 1-4; The method for preparing the flame-retardant material includes: The raw materials for preparing the flame retardant material are subjected to cold sintering treatment to obtain a glass-flame retardant composite, wherein the glass-flame retardant composite includes a sulfonate flame retardant and a glass layer covering the outside of the sulfonate flame retardant; The glass-flame retardant composite is ground and purified to obtain the flame retardant material.

6. The method for preparing the flame-retardant material according to claim 5, characterized in that, The raw materials for preparing the flame-retardant material are subjected to cold sintering treatment to obtain a glass-flame-retardant composite, comprising: Under a pressure of 300MPa-400MPa, the raw materials for preparing the flame retardant material are heated to 130℃-180℃ at a set heating rate, and after heat preservation and pressure treatment, the glass-flame retardant composite is obtained.

7. A polycarbonate composite material, characterized in that, The polycarbonate composite material comprises the following components in the indicated mass percentages: The flame retardant material according to any one of claims 1-4 comprises 0.1%-2%, polycarbonate resin 91%-99.6%, toughening agent 0-5%, and additives 0.2%-2%.

8. The polycarbonate composite material according to claim 7, characterized in that, The toughening agent is selected from at least one of the following: methyl methacrylate-organosilicon-acrylate terpolymer, methyl methacrylate-butadiene-styrene terpolymer, ethylene-1-octene copolymer, ethylene-methyl acrylate-glycidyl methacrylate terpolymer, maleic anhydride-grafted ethylene-propylene diene monomer (EPDM) rubber, maleic anhydride-grafted ethylene-1-octene copolymer, and chlorinated polyethylene.

9. The polycarbonate composite material according to claim 7, characterized in that, The additive is selected from at least one of antioxidants and lubricants.

10. A method for preparing a polycarbonate composite material, characterized in that, The polycarbonate composite material is as described in any one of claims 7-9; The method for preparing the polycarbonate composite material includes: performing injection molding or extrusion processing on each component of the uniformly mixed polycarbonate composite material under a set temperature gradient to obtain the polycarbonate composite material.

11. The polycarbonate composite material according to claim 10, characterized in that, The melt flow rate of the polycarbonate resin is 8 g / 10 min to 22 g / 10 min.

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