TWI380969B - The composition and application of mica/born nitride ceramic composite powder - Google Patents

Description

Composition and application of mica/boron nitride composite ceramic powder

The invention relates to the composition and application of a composite material; the composite material is an inorganic composite powder composed of mica and boron nitride powder; the inorganic composite powder is used in the field of composite engineering plastics.

A composite material is defined as a heterogeneous solid material composed of two or more substances having different physical or chemical properties. In the composite material, one is usually a continuous phase, which is a matrix material; the other is a dispersed phase, which is a reinforcing material. In the prior art, there are quite a few examples of disperse phase materials using mica powder or boron nitride powder as composite materials, which increases the function and use of the composite material.

Taking the application of mica powder as an example: the Republic of China patent TW 127429 uses mica powder as an additive to produce fire-resistant composite sheets with good fire resistance, heat resistance and water resistance; the Republic of China patent TW 208697 publishes mica powder as ultraviolet light. Interrupting agent, used in the field of cosmetics; Republic of China public patent TW 200619293, with mica as additive material, applied to composite materials with high tensile strength, high elasticity and/or small thickness; Republic of China patent TW 557315 published with mica powder as A filler material for a car bumper that reduces cost and maintains impact strength and tensile strength. Based on the previous literature, mica powder in the application of engineering plastics, the benefits are to enhance the fire resistance, heat resistance, tensile strength, impact strength, UV resistance, heat distortion temperature, and electrical Insulation and other functions. However, the engineering plastics added to the mica powder The disadvantage is that the plastic color is dull and dull, and the thermal conductivity is PPP (~0.6W/mK).

Taking the application of boron nitride powder as an example: U.S. Patent No. 6,831,031 uses boron nitride as a plastic additive material for the field of high heat transfer engineering plastics; the Republic of China patent TW I326298 publishes the addition of boron nitride powder to the paint. It has the effect of heat dissipation and reflection. Based on the previous literature, boron nitride powder in the application of engineering plastics, the benefits of enhancing the thermal conductivity of plastics, reflective effects, and high whiteness. However, when boron nitride powder is used in the production of engineering composite plastics, the disadvantage is that the dispersion of boron nitride powder in plastics is poor and expensive, and the two main reasons are that boron nitride composite plastics cannot be used on a large scale. The field of application of consumer electronics.

The object of the present invention is to provide a composite ceramic powder which is a composite powder of mica and boron nitride powder sintered to each other, and is applied to a filling powder of a composite engineering plastic; and has the characteristics and functions of mica and boron nitride at the same time, and Solve the disadvantages of mica and boron nitride as filler powders, and provide good dispersibility and processability.

In addition, the present invention also proposes a ceramic powder composite plastic material with boron nitride/mica composite powder, which can solve the disadvantages of a single filler material: it solves the problem of dispersion of boron nitride filler and high cost; and also solves the problem of mica filling composite Plastic dull and dull colors. In addition, the ceramic powder composite plastic material has the functions and advantages of mica composite plastic and boron nitride composite plastic: excellent fire resistance, heat resistance, tensile strength, impact strength, UV resistance, electrical Functions and features such as insulation capacity, heat distortion temperature, heat transfer properties, thermal diffusion properties, low specific heat, gloss, whiteness, and low cost.

The composition of the boron nitride/mica composite ceramic powder 13 of the present invention comprises 90% to 10% by weight of boron nitride powder 11 and 10% to 90% by weight of mica powder 12, and the two solid powders The body is uniformly distributed, wherein the aforementioned mica powder is a scaly powder having an average particle diameter of 1 μm to 25 μm, and the powder type includes biotite, Phlogopite, Muscovite, sericite ( Sericite), Lipirolite, Zilnwaldite, or a mixture of the above; and boron nitride powder is a scaly, scaly or spherical powder having an average particle size of 1 to 50 μm. The body type includes hexagonal boron nitride, cubic boron nitride, dense boron nitride, or a mixed form of the above various types.

In the production process, the boron nitride powder 11 and the mica powder 12 described above are mixed and sintered at a high temperature to produce a boron nitride/mica composite ceramic powder 13. The sintering temperature is 300 ° C ~ 1250 ° C, and the sintering time is 1 ~ 12 hours.

In addition, the composite ceramic powder is treated with a coupling agent as a surface treatment to enhance the dispersion and bridging effect of the composite ceramic powder and the organic material, and the coupling agent is added in an amount of 0.2% to 3% by weight of the composite ceramic powder. The coupling agent type includes a silane (Sliane) coupling agent, a titanate coupling agent, a zirconate coupling agent, an organic chromium complex (Chromium Complex) coupling agent, or the like. A mixture of coupling agents.

The invention further comprises a boron nitride/mica composite plastic material, the composition comprising a boron nitride/mica composite ceramic powder, an organic resin, and a coupling agent. The organic resin type includes a thermoplastic resin, a thermosetting resin or a photocrosslinkable resin; and the coupling agent functions as a bridging agent for the inorganic powder and the organic resin, and contributes to dispersion of the inorganic powder, and the form thereof comprises A silane coupling agent, a titanate coupling agent, a zirconate coupling agent, an organic chromium complex coupling agent, or a mixture of the above various coupling agents.

The weight ratio of the boron nitride/mica composite ceramic powder to the boron nitride/mica composite plastic material is 20% to 70%; the weight of the coupling agent in the boron nitride/mica composite plastic material The ratio is 0.2% to 1%. The boron nitride/mica composite plastic material produced is a lustrous white, milky white, gray or dark brown composite engineering plastic; and is also an electrical insulating composite engineering plastic; it has better thermal properties than the plastic substrate, wherein Contains higher heat transfer coefficient, higher thermal diffusivity, lower specific heat, and higher heat emissivity. The higher the weight percentage of the boron nitride/mica composite ceramic powder, the better the thermal properties of the boron nitride/mica composite plastic material applied.

In the foregoing boron nitride/mica composite plastic material, the proportion of mica and boron nitride added is 10% to 90% by weight of mica powder and 90% to 10% by weight of boron nitride powder. When the proportion of the weight of the mica powder is higher, the dispersibility of the composite powder in the organic resin is better and the price is cheaper; and the higher the proportion of the weight of the boron nitride, the boron nitride applied/ The better the thermal properties of the mica composite plastic material, the higher the whiteness of the color.

Example

Preparing hexagonal boron nitride powder 11 and mica powder 12, uniformly mixing in a ratio of 1:1; and sintering the mixed powder at a temperature of 800 ° C to 1000 ° C for 2 to 5 hours to produce a boron nitride / mica composite Ceramic powder 13; treated with a 1% by weight silane coupling agent for the surface of the boron nitride/mica composite powder.

Then, the boron nitride/mica composite plastic material is produced by plastic injection molding technology, and the nylon 66 resin and the boron nitride/mica composite ceramic powder are separately transported by the twin-screw extruder; when the extruder for conveying the nylon 66 resin is stably operated, The boron nitride/mica composite ceramic powder can be discharged from the downstream side feed port; the boron nitride/mica composite ceramic powder and the nylon 66 resin are uniformly mixed, and the plastic injection molding operation is performed. The boron nitride/mica composite ceramic powder accounts for 40% by weight of the composite plastic material. In addition, nylon 66 plastic sheet was produced by injection molding technology as a control group for pattern and function comparison.

Fig. 1 and Fig. 2 are photographs and SEM images of nylon 66 plastic sheet 20 and boron nitride/mica composite plastic sheet 30, respectively. Fig. 2(a) shows that the boron nitride/mica composite plastic material 30 is a glossy white plastic. Figure 1 (b) shows the SEM image of nylon 66 plastic microstructure 201, which shows the fibrous microstructure of nylon 66 plastic; and Figure 2 (b) shows the microstructure of boron nitride/mica composite plastic material 301 It can be seen that two types of substances are mixed therein, which are nylon 66 plastic 14 and boron nitride/mica composite ceramic powder 13.

The thermal properties of nylon 66 plastic sheet and boron nitride/mica composite plastic sheet are tested by ISO-22007 (Hot Disk) method, and the thermal properties include thermal conductivity, thermal diffusion coefficient, and thermal diffusion coefficient (Thermal Diffusivity). Heat Capacity. Figure 3 shows the relationship between the proportion of boron nitride/mica composite powder and thermal properties. When the proportion of boron nitride/mica composite powder is 0%, it is pure nylon 66 plastic material; Figure 3 (a), (b), and (c) show that when the boron nitride/mica composite powder accounts for a higher percentage of weight, the heat transfer coefficient increases, the thermal diffusivity increases, and the specific heat decreases (ie, Compared with no heat accumulation phenomenon; when the added weight percentage of boron nitride/mica composite powder is 40%, the heat transfer coefficient is ~3 times that of nylon 66 plastic material, and the thermal diffusivity is pure nylon 66 plastic material~ 5 times, and the specific heat is ~0.5 times that of pure nylon 66 plastic material. The test results show that the boron nitride/mica composite powder can greatly improve the thermal properties of the composite plastic.

11‧‧‧ boron nitride powder

12‧‧‧mica powder

13‧‧‧Boron nitride/mica composite ceramic powder

14‧‧‧Nylon 66 plastic

20‧‧‧Nylon 66 plastic sheet

201‧‧‧Nylon 66 plastic microstructure

30‧‧‧Boron nitride/mica composite plastic sheet

301‧‧‧Non-boron nitride/mica composite plastic microstructure

Figure 1 is a (a) photo and (b) SEM image of a nylon 66 plastic sheet.

Figure 2 is a (a) photo and (b) SEM image of a boron nitride/mica composite plastic sheet.

Figure 3 is the thermal property test results of plastic materials (a) heat transfer coefficient, (b) thermal diffusivity, and (c) specific heat

13‧‧‧Boron nitride/mica composite ceramic powder

14‧‧‧Nylon 66 plastic

30‧‧‧Boron nitride/mica composite plastic sheet

301‧‧‧Non-boron nitride/mica composite plastic microstructure

Claims (23)

A composite ceramic powder comprising mica powder, which is a scaly powder; a boron nitride powder, which is a scaly, scaly or spherical powder; the composite ceramic powder is mixed and sintered Made as a filler for organic resins. The composite ceramic powder according to claim 1, wherein the mica powder has an average particle diameter of 1 μm to 25 μm; and the boron nitride powder has an average particle diameter of 1 μm to 50 μm. The composite ceramic powder according to claim 1, wherein the weight ratio of the mica powder to the composite ceramic powder is 10% to 90%. The composite ceramic powder according to claim 1, wherein the mica powder type comprises biotite, phlogopite, muscovite, sericite, lithium mica, iron lithium mica, or a mixture of the above. The composite ceramic powder according to claim 1, wherein the boron nitride powder comprises hexagonal boron nitride, cubic boron nitride, dense boron nitride, or a mixture of the above various types. The composite ceramic powder according to claim 1, wherein the sintering temperature of the sintering process is 300 ° C to 1250 ° C, and the sintering time is 1 to 12 hours. The composite ceramic powder according to claim 1, wherein the composite ceramic powder is treated with a coupling agent for enhancing the dispersion and bridging effect of the composite ceramic powder and the organic material; wherein the coupling agent type A silane coupling agent, a titanate coupling agent, a zirconate coupling agent, an organic chromium complex coupling agent, or a mixture of the above various coupling agents is contained. The composite ceramic powder according to claim 1, wherein the composite ceramic powder is used as a filler for an organic resin, wherein the organic resin comprises a thermoplastic resin, a thermosetting resin, a photocrosslinking resin, or the like. A mixture of various resins. A composite ceramic powder comprising mica powder, which is a scaly powder; a boron nitride powder, which is a scaly, scaly or spherical powder; a coupling agent, which is bonded to the surface of the powder; The composite ceramic powder is obtained by a mixing, sintering and surface coupling agent treatment process. The composite ceramic powder according to claim 9, wherein the mica powder has an average particle diameter of 1 μm to 25 μm; and the boron nitride powder has an average particle diameter of 1 μm to 50 μm. The composite ceramic powder according to claim 9 , wherein the weight ratio of the mica powder to the composite ceramic powder is 10% to 90%. The composite ceramic powder according to claim 9, wherein the mica powder type comprises biomica, phlogopite, muscovite, sericite, lithium mica, iron lithium mica, or a mixture of the above. The composite ceramic powder according to claim 9, wherein the boron nitride powder comprises hexagonal boron nitride, cubic boron nitride, dense boron nitride, or a mixed species of the above various types. The composite ceramic powder according to claim 9, wherein the sintering temperature of the sintering process is 300 ° C to 1250 ° C, and the sintering time is 1 to 12 hours. The composite ceramic powder according to claim 9, wherein the coupling agent is used for enhancing the dispersion and bridging effect of the composite ceramic powder and the organic material; wherein the coupling agent type comprises a silane coupling agent and a titanate. A coupling agent, a zirconate coupling agent, an organic chromium complex coupling agent, or a mixture of the above various coupling agents. A ceramic powder composite material comprising a composite ceramic powder, which is a composite powder of mica powder and boron nitride powder co-sintered; An organic resin, which serves as a matrix of a composite material; a coupling agent, which acts as a bridging agent for inorganic powders and organic resins, and facilitates dispersion and bridging of inorganic powders and organic substrates. For example, the composite ceramic powder described in claim 16 has a sintering process temperature of 300 ° C to 1250 ° C and a sintering time of 1 to 12 hours. The ceramic powder composite material according to claim 16, wherein the composite ceramic powder accounts for 20% to 70% by weight of the ceramic powder composite material. The ceramic powder composite material according to claim 16, wherein the organic resin comprises a thermoplastic resin, a thermosetting resin, a photocrosslinking resin, or a mixture of the above various resins. The ceramic powder composite material according to claim 16, wherein the coupling agent type comprises a silane coupling agent, a titanate coupling agent, a zirconate coupling agent, an organic chromium complex coupling agent, or A mixture of the above various coupling agents. The ceramic powder composite material according to claim 16 is a glossy white, milky white, gray, or dark brown composite engineering plastic. The ceramic powder composite material as claimed in claim 16 is an electrical insulation composite engineering plastic. The ceramic powder composite material as claimed in claim 16 is a thermally conductive composite engineering plastic; the composite ceramic powder added therein promotes the thermal properties of the ceramic powder composite material, wherein the thermal properties include an increase in heat transfer coefficient, Improve the thermal diffusivity, reduce the specific heat, and improve the heat radiation rate.