A composite material for rubber-plastic parts and a preparation method and application thereof

Abstract

The application discloses a kind of composite materials for rubber and plastic fittings and its preparation method and application, it is related to material technical field, the raw material of the composite materials for rubber and plastic fittings includes following mass fraction: rubber and plastic matrix resin 100 parts, nano heat-conducting reinforcing agent 1-5 parts, rheological modifier 0.5-3 parts, anti-aging auxiliary agent 1-4 parts and functional filler 5-15 parts, the mass ratio of the nano heat-conducting reinforcing agent and the rheological modifier is 1: (0.2~0.8), by scientific proportioning rubber and plastic matrix resin, nano heat-conducting reinforcing agent, rheological modifier, anti-aging auxiliary agent and functional filler, make each component in the process of melt mixing produce synergistic effect, the process tolerance and product yield of this composite material are improved from formula source, effectively solve the problem that electronic rubber and plastic fittings precision is low under traditional process, compatibility is poor and service life is short.

Description

Technical Field

[0001] This invention relates to the field of materials technology, and in particular to a composite material for rubber and plastic parts, its preparation method, and its application. Background Technology

[0002] In the fields of industrial control equipment, new energy electronics, and precision consumer electronics, rubber and plastic protective components (such as sealing rings and insulating gaskets) play a crucial role. However, the industry currently mostly adopts the traditional segmented production process, in which raw material mixing, molding, and post-processing are carried out independently in separate steps. This process route has significant drawbacks: on the one hand, multiple material transfers and temperature changes lead to residual internal stress in the materials, making the finished products prone to problems such as large dimensional deviations, warping deformation, and numerous surface defects, making it difficult to meet high-precision assembly requirements; on the other hand, traditional fixed process parameters cannot be adapted to various differentiated materials such as modified silicone rubber, flame-retardant ABS, and soft TPE, resulting in high production switching costs and low efficiency. Furthermore, due to the lack of integrated stress relief and anti-aging treatment, the products are prone to cracking and performance degradation after long-term use. Summary of the Invention

[0003] The main objective of this invention is to propose a composite material for rubber and plastic parts, its preparation method, and its application. This invention aims to solve the problems that traditional fixed process parameters cannot be adapted to various differentiated materials such as modified silicone rubber, flame-retardant ABS, and soft TPE, and that production switching costs are high and long-term use is prone to cracking and performance degradation.

[0004] To achieve the above objectives, the present invention proposes a composite material for rubber and plastic parts, wherein the raw materials of the composite material for rubber and plastic parts comprise the following parts by weight: The mixture comprises 100 parts of rubber and plastic matrix resin, 1-5 parts of nano thermally conductive reinforcing agent, 0.5-3 parts of rheology modifier, 1-4 parts of anti-aging additive, and 5-15 parts of functional filler, wherein the mass ratio of the nano thermally conductive reinforcing agent to the rheology modifier is 1:(0.2~0.8).

[0005] In one embodiment, the rubber-plastic matrix resin is any one of modified silicone rubber, flame-retardant ABS, and flexible TPE; and / or, The rheology modifier includes at least one of acrylate copolymers, maleic anhydride graft copolymers, and silicone-polyurethane copolymers; and / or, The functional filler includes at least one of micron-sized magnesium hydroxide, graphene-like kaolin, and hollow glass microspheres.

[0006] In one embodiment, the nano-thermal conductive reinforcing agent is prepared from nano-reinforcing materials modified with a silane coupling agent and inorganic rigid particles: The nano-reinforcing material includes at least one of carbon nanotubes, carbon nanofibers, and graphene; and / or, The inorganic rigid particles include at least one of nano-alumina, nano-silicon oxide, and nano-magnesium oxide.

[0007] In one embodiment, the mass ratio of the inorganic rigid particles to the nano-reinforcing material is (3~25):1.

[0008] In one embodiment, the anti-aging additives include hindered amine light stabilizers and hindered phenolic antioxidants.

[0009] In one embodiment, the mass ratio of the hindered amine light stabilizer to the hindered phenolic antioxidant is 1:(1~2.5); and / or, The hindered amine light stabilizer includes light stabilizer CyasorbUV-3346 or light stabilizer 944; and / or, The hindered phenolic antioxidants include antioxidant 1010.

[0010] This invention also provides a method for preparing a composite material for rubber and plastic parts, comprising the following steps: S1. Premix the rubber and plastic matrix resin, rheology modifier and anti-aging additive to form a premix; S2. Mix the nano-thermal conductive reinforcing agent with the functional filler and perform in-situ surface modification to obtain the composite filler; S3. The premixed material and the compound filler are injected into a twin-screw extruder, and after melt mixing and extrusion granulation, a composite material for rubber and plastic parts is obtained.

[0011] In one embodiment, when the rubber-plastic matrix resin is modified silicone rubber, the melt flow rate of the composite material for rubber-plastic parts is 5-15 g / 10 min within a processing window of 180°C to 220°C; and / or, When the rubber and plastic matrix resin is flame-retardant ABS or soft TPE, the melt flow rate of the composite material for rubber and plastic parts is 10~25 g / 10min in the processing window of 200℃~230℃.

[0012] In one embodiment, in step S3, the temperature of each zone of the twin-screw extruder includes 170°C to 230°C.

[0013] This invention provides the application of the aforementioned composite material for rubber and plastic parts in industrial control equipment, new energy electronics, or precision consumer electronics.

[0014] In this invention, a material system with excellent comprehensive performance is constructed by introducing specific mass proportions of nano-thermal conductive reinforcing agents, rheology modifiers, anti-aging additives, and functional fillers, with rubber and plastic matrix resin as the main body. The synergistic effect of the rheology modifier and functional filler effectively improves melt flowability and dimensional stability, solving the problems of warpage and shrinkage; the nano-thermal conductive reinforcing agent improves density and mechanical strength while also meeting heat dissipation requirements; and the addition of the anti-aging additive significantly enhances the material's weather resistance. This invention, through the scientific proportioning of rubber and plastic matrix resin, nano-thermal conductive reinforcing agents, rheology modifiers, anti-aging additives, and functional fillers, enables each component to produce a synergistic effect during melt mixing. This composite material improves process tolerance and product yield from the formulation source, effectively solving the problems of low precision, poor compatibility, and short lifespan of electronic rubber and plastic parts under traditional processes. Detailed Implementation

[0015] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Where the manufacturers of reagents or instruments are not specified, they are all conventional products that can be purchased commercially. Furthermore, the meaning of "and / or" throughout the text includes three parallel solutions; for example, "A and / or B" includes solution A, or solution B, or a solution where both A and B are satisfied simultaneously. In addition, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by 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.

[0016] In the fields of industrial control equipment, new energy electronics, and precision consumer electronics, rubber and plastic protective components (such as sealing rings and insulating gaskets) play a crucial role. However, the industry currently mostly adopts the traditional segmented production process, in which raw material mixing, molding, and post-processing are carried out independently in separate steps. This process route has significant drawbacks: on the one hand, multiple material transfers and temperature changes lead to residual internal stress in the materials, making the finished products prone to problems such as large dimensional deviations, warping deformation, and numerous surface defects, making it difficult to meet high-precision assembly requirements; on the other hand, traditional fixed process parameters cannot be adapted to various differentiated materials such as modified silicone rubber, flame-retardant ABS, and soft TPE, resulting in high production switching costs and low efficiency. Furthermore, due to the lack of integrated stress relief and anti-aging treatment, the products are prone to cracking and performance degradation after long-term use.

[0017] In view of this, the present invention provides a composite material for rubber and plastic parts, wherein the raw materials of the composite material for rubber and plastic parts comprise the following parts by weight: The mixture comprises 100 parts of rubber and plastic matrix resin, 1-5 parts of nano thermally conductive reinforcing agent, 0.5-3 parts of rheology modifier, 1-4 parts of anti-aging additive, and 5-15 parts of functional filler, wherein the mass ratio of the nano thermally conductive reinforcing agent to the rheology modifier is 1:(0.2~0.8).

[0018] In this invention, a material system with excellent comprehensive performance is constructed by introducing specific mass proportions of nano-thermal conductive reinforcing agents, rheology modifiers, anti-aging additives, and functional fillers, with rubber and plastic matrix resin as the main body. The synergistic effect of the rheology modifier and functional filler effectively improves melt flowability and dimensional stability, solving the problems of warpage and shrinkage; the nano-thermal conductive reinforcing agent improves density and mechanical strength while also meeting heat dissipation requirements; and the addition of the anti-aging additive significantly enhances the material's weather resistance. This invention, through the scientific proportioning of rubber and plastic matrix resin, nano-thermal conductive reinforcing agents, rheology modifiers, anti-aging additives, and functional fillers, enables each component to produce a synergistic effect during melt mixing. This composite material improves process tolerance and product yield from the formulation source, effectively solving the problems of low precision, poor compatibility, and short lifespan of electronic rubber and plastic parts under traditional processes.

[0019] Specifically, the mass ratio of the nano-thermal conductive reinforcing agent to the rheology modifier can be 1:0.2, 1:0.3, 1:0.5, or 1:0.8. The rheology modifier introduced in this invention at a specific ratio undergoes microscopic entanglement with the long chains of the coupling agent on the surface of the nano-thermal conductive reinforcing agent, thus encapsulating the surface of the nano-thermal conductive reinforcing agent. This encapsulation layer triggers a unique 'shear thinning' behavior under strong shear force, acting as a microscopic 'ball bearing' at the phase interface between the matrix and the rigid filler, providing excellent molecular chain deentanglement and fluid lubrication, significantly reducing the macroscopic viscosity of the melt. This allows the internal microscopic thermal stress and mechanical orientation stress of the composite material to be efficiently and spontaneously relaxed and released during molding and cooling, resulting in a significant reduction in residual stress in the finished product. Consequently, the residual stress of the material of this invention is significantly reduced after undergoing severe thermal shock, greatly improving the dimensional accuracy of the product and fundamentally solving the problems of large dimensional deviations, warping deformation, and easy cracking caused by traditional segmented processes.

[0020] Specifically, taking carbon nanotubes and nano-alumina as examples, the nano-alumina (inorganic rigid particles) and multi-walled carbon nanotubes (nano-reinforced materials) after KH-550 surface modification are enriched with highly active amino functional groups. During melt extrusion, the carbon nanotubes with extremely high aspect ratios and the nano-alumina with high specific surface area spontaneously construct a continuous 'point-line' interwoven network through electrostatic attraction and hydrogen bonding induced by these surface functional groups, forming an in-situ self-assembled network. Heat can be conducted at high speed along this one-dimensional / three-dimensional phonon channel with extremely low interfacial thermal resistance, thus breaking the limitation of traditional thermally conductive materials requiring massive amounts of inorganic fillers, and achieving high thermal conductivity under low filler load.

[0021] In some embodiments of the present invention, the rubber-plastic matrix resin is any one of modified silicone rubber, flame-retardant ABS, and soft TPE.

[0022] Flame-retardant ABS can effectively improve the fire safety level and mechanical strength of materials, while soft TPE combines the high elasticity of rubber with the ease of processing of plastics. This flexible material selection strategy not only optimizes the weather resistance, chemical corrosion resistance and tactile experience of products, but also effectively meets the stringent material requirements of different fields such as medical devices, automotive parts and electronic products.

[0023] In some embodiments of the present invention, the rheology modifier includes at least one of acrylate copolymers, maleic anhydride graft copolymers, and silicone-polyurethane copolymers.

[0024] The rheology modifiers using the above materials have dual functional groups on their molecular chains that can unify the shear viscosity of silicone rubber, ABS, or TPE in the molten state. Combined with specific functional fillers, the materials not only have high adaptability to production, but also have excellent flame retardancy, lightweighting, or crack resistance.

[0025] In summary, by limiting specific categories of matrix resins, rheology modifiers, and functional fillers, the application of a single additive system across materials has been achieved. Specific copolymers such as acrylates, maleic anhydride grafts, or silicone-polyurethane, as rheology modifiers, can unify the shear viscosity of silicone rubber, ABS, or TPE—three materials with drastically different polarities and molecular chain structures—in the molten state through their dual functional groups on their molecular chains. Combined with specific functional fillers, the materials not only possess high adaptability to production but also excellent flame retardancy, lightweighting, or crack resistance.

[0026] In some embodiments of the present invention, the functional filler includes at least one of micron-sized magnesium hydroxide, graphene-like kaolin, and hollow glass microspheres.

[0027] Furthermore, the average particle size of the functional filler is 1~10μm.

[0028] In some embodiments of the present invention, the nano-thermal conductive reinforcing agent is prepared by nano-reinforcing materials modified with silane coupling agents and inorganic rigid particles.

[0029] High-strength one-dimensional nano-reinforcing materials, acting as a microscopic 'steel skeleton,' can withstand and stretch localized stress, while nano-inorganic rigid particles play a role in sliding lubrication and filling support when the matrix is ​​subjected to microscopic compression. This combination of rigidity and flexibility in the 'microscopic skeleton' enables the finished product to achieve extremely low residual stress.

[0030] Furthermore, the nano-reinforcing material includes at least one of carbon nanotubes, carbon nanofibers, and graphene, and the inorganic rigid particles include at least one of nano-alumina, nano-silicon oxide, and nano-magnesium oxide.

[0031] Furthermore, the mass ratio of the inorganic rigid particles to the nano-reinforcing material is (3~25):1, specifically, it can be 3:1, 5:1, 20:1 or 25:1.

[0032] If the proportion of inorganic rigid particles is too low, there will be too many one-dimensional linear carbon nanotubes in the system, which are prone to self-entanglement and aggregation, and there will be a lack of sufficient alumina to bridge the gaps, resulting in increased thermal resistance at the phonon conduction points. If the proportion is too high, the carbon nanotubes will be over-diluted, unable to form continuous long-distance one-dimensional pathways, and the thermal conductivity network will degenerate into isolated point contacts, resulting in a precipitous drop in thermal conductivity. Therefore, by adjusting the range to the above-mentioned range, a balance is achieved between rigid particles and reinforcing materials. A small amount of carbon nanotubes extend for a long time, while a large amount of nano-alumina acts as microscopic "ball bearings" and "transfer stations," filling the three-dimensional mesh between the carbon nanotubes. This spatial occupancy synergy minimizes the interfacial thermal resistance for phonon transmission, thereby macroscopically resulting in extremely high thermal conductivity and extremely low residual stress.

[0033] In some embodiments of the present invention, the anti-aging adjuvant includes hindered amine light stabilizers and hindered phenolic antioxidants, and the mass ratio of the hindered amine light stabilizers to the hindered phenolic antioxidants is 1:(1~2.5).

[0034] It should be noted that during the premixing and integrated continuous shear mixing process, the polarity of the hydrophilic and lipophilic dual functional groups in the rheology modifier with a specific structure is utilized to induce the hindered amine light stabilizer and the hindered phenolic antioxidant to segregate and migrate to the highly polar "resin-filler" phase interface under the spontaneous thermodynamic drive. The interface is anchored through the microscopic intermolecular hydrogen bonds between the hindered phenolic hydroxyl groups, the hindered amine groups and the coupling agent on the filler surface. After cooling and solidification, a coating layer is constructed in situ, forming a continuous molecular-level coating network that synergistically blocks the diffusion of oxygen and ultraviolet rays. This microscopically breaks the free radical aging transmission chain caused by heat, light and oxygen in the material, resulting in a significant improvement in the tensile strength and elongation at break retention rate of the components under long-term high temperature or variable and complex industrial control and new energy electronic environments, exhibiting excellent anti-aging and anti-performance degradation capabilities.

[0035] This invention also provides a method for preparing a composite material for rubber and plastic parts, comprising the following steps: S1. Premix the rubber and plastic matrix resin, rheology modifier and anti-aging additive to form a premix; S2. Mix the nano-thermal conductive reinforcing agent with the functional filler and perform in-situ surface modification to obtain the composite filler; S3. The premixed material and the compound filler are injected into a twin-screw extruder, and after melt mixing and extrusion granulation, a composite material for rubber and plastic parts is obtained.

[0036] The preparation method of this invention breaks through the drawbacks of traditional raw material mixing and molding, which are carried out in separate steps. By first premixing and coating, then modifying the filler in situ, and finally integrating the mixing in one step, the process of material transfer and thermal history switching is shortened. The seamless synergy between this process and the specific rheological formulation minimizes the residual stress accumulated by the material due to multiple temperature changes, and ensures the stability and uniformity of the composite material performance from the source of the preparation process.

[0037] In some embodiments of the present invention, when the rubber-plastic matrix resin is modified silicone rubber, the melt flow rate of the composite material for rubber-plastic parts is 5~15 g / 10min in a processing window of 180℃~220℃, and / or; When the rubber and plastic matrix resin is flame-retardant ABS or soft TPE, the melt flow rate of the composite material for rubber and plastic parts is 10~25 g / 10min in the processing window of 200℃~230℃.

[0038] For the two completely different types of processed melt characteristics, modified silicone rubber and flame-retardant ABS / soft TPE, a precise melt flow rate (MFR) quantification range is given. This proves that the formulation of the present invention can provide excellent melt flowability and homogeneity within the most suitable processing temperature window according to different resin matrices, avoiding local shear overheating or insufficient mold filling, and providing a standard quantifiable processing index for the flawless molding of high-precision protective accessories.

[0039] In some embodiments of the present invention, in step S3, the temperature of each zone of the twin-screw extruder includes 170°C to 230°C. Specifically, it varies depending on the provided rubber and plastic matrix resin and can be 170°C, 180°C, 190°C, 200°C, or 230°C. Within the above range, the thermally reactive functional groups in the rheology modifier fully react without causing thermal degradation of the anti-aging additives and matrix resin. Under this temperature control, integrated mixing can achieve the optimal state of the compound fillers and maximize the comprehensive protective performance of the composite material.

[0040] The composite material for rubber and plastic parts described in this invention is used in industrial control equipment, new energy electronics, or precision consumer electronics.

[0041] Experimental materials Flame-retardant ABS resin: Kingfa Science & Technology's FRABS-Active Flame Retardant Grade, JH960-V0.

[0042] Methyl vinyl silicone rubber: Methyl vinyl silicone rubber produced by Hoshine Silicon Industry Co., Ltd., grade HSR-201.

[0043] Soft SEBS / PP: Commercial TPE elastomer (brand name: KingfaTPE A55) manufactured by Kingfa Science & Technology Co., Ltd.

[0044] Preparation of the nano-thermal conductive reinforcing agent: Anhydrous ethanol and water were first mixed at a volume ratio of 9:1 to obtain a mixed solvent. Five parts of multi-walled carbon nanotubes (as nano-reinforcing materials) and 95 parts of nano-alumina (as inorganic rigid particles) were weighed and added to the mixed solvent, controlling the solid-liquid ratio at 1:10 (g / mL). Subsequently, 1% (by mass) of silane coupling agent KH-550 (equivalent to the total mass of multi-walled carbon nanotubes and nano-alumina) was added. The mixture was ultrasonically dispersed and continuously stirred for 2 hours under a 70℃ water bath. After the reaction, the mixture was filtered, and the filter cake was washed three times with anhydrous ethanol to remove residual free coupling agent from the surface. The filter cake was then randomly placed in an 80℃ vacuum oven and dried for 12 hours to obtain the surface-modified nano-thermal conductive reinforcing agent, which is denoted as the reinforcing agent in Table 1.

[0045] Preparation steps of anti-aging additive: It is composed of 1 part light stabilizer 944 and 1.5 parts antioxidant 1010, which is recorded as composite anti-aging agent in Table 1.

[0046] The rheology modifier is methyl methacrylate-butyl acrylate copolymer, manufactured by Shandong Ruifeng High-Tech Materials Co., Ltd., commercial model: ACR-401.

[0047] The technical solution of the present invention will be further described in detail below with reference to specific embodiments. It should be understood that the following embodiments are only used to explain the present invention and are not intended to limit the present invention.

[0048] Example 1 A method for preparing a composite material for rubber and plastic parts includes the following steps: S1. Weigh 100kg of halogen-free flame-retardant ABS resin, 1.35kg of rheology modifier (ACR-401), and 2.5kg of anti-aging additive. Put the above raw materials into a high-speed mixer and premix at 70℃ for 12 minutes to obtain a premix. S2. Weigh 3 kg of nano thermally conductive reinforcing agent and 10 kg of functional filler (hollow glass microspheres with a density of 0.37 g / cm³, an average particle size of 45 μm, and a compressive strength of 20.68 MPa), and stir at high speed for 5 min to obtain the compound filler; S3. The premix obtained in step S1 is fed into a co-rotating twin-screw extruder through the main feed port, and the compound filler obtained in step S2 is fed into the extruder through the side feed port. The screw speed is set to 300 rpm, the temperature of zone 1 (feeding zone) of the extruder is 160℃, the temperature of zones 2 to 5 (melt mixing zone) is 200℃, the temperature of zones 6 to 8 (venting shear zone) is 210℃ and vacuum devolatilization with a vacuum degree of -0.08MPa is activated, and the temperature of zone 9 (die zone) is 200℃. The melt is extruded in strips, cooled in a water-cooling tank, air-dried, and then fed into a pelletizer for pelletizing to obtain the rubber and plastic parts composite material of Example 1. The melt flow rate (MFR) of the rubber and plastic parts composite material obtained in this example is 16.2 g / 10min at 210℃ and 5kg load.

[0049] It should be noted that by replacing the halogen-free flame-retardant ABS resin with an equal mass of methyl vinyl silicone rubber, and controlling the temperature of the extruder zone 1 (feeding zone) at 60℃, the temperature of the melt mixing zone at 140℃~160℃, and the temperature of zone 9 (die zone) at 150℃, a composite material for rubber and plastic parts can be obtained.

[0050] The halogen-free flame-retardant ABS resin was replaced with an equal mass of soft SEBS / PP. The temperature of the extruder zone 1 (feeding zone) was controlled at 150°C, the temperature of the melt mixing zone was controlled at 180°C~200°C, and the temperature of zone 9 (die zone) was controlled at 180°C. The remaining steps were exactly the same as in Example 1, and a composite material for rubber and plastic parts was obtained.

[0051] Examples 2 to 5 use similar steps to those in Example 1 to prepare composite materials for rubber and plastic parts. The difference is that the materials and / or amounts of the composite materials for rubber and plastic parts are different. The mass ratio of the nano-thermal conductive reinforcing agent to the rheology modifier is denoted as m. For specific differences, please refer to Table 1.

[0052] Table 1

[0053] Performance testing The composite materials for rubber and plastic parts prepared in Examples 1-3 and Comparative Examples 1-4 were subjected to the following tests: 1. Internal residual stress test: Refer to GB / T7760 standard to determine the residual stress in the central area of ​​the injection-molded gasket.

[0054] 2. Melt Flow Rate (MFR) Test: A melt flow rate meter was used, referring to GB / T3682 standard. Silicone rubber-based samples were tested at 190℃ and 5kg; ABS and TPE-based samples were tested at 220℃ and 10kg.

[0055] 3. Accelerated hot air aging test: Place the sample in an aging test chamber with forced air circulation and age it continuously in hot air at 120℃ for 500 hours, referring to GB / T3512. Test the tensile strength and elongation at break before and after aging, and calculate the retention rate.

[0056] 4. Thermal conductivity test: The axial thermal conductivity of the sample at 25℃ was measured using a laser thermal conductivity meter (LFA) in accordance with GB / T22588 standard.

[0057] 5. Cyclic thermal shock and dimensional change rate test: The high-precision sealing gasket was placed in a thermal shock test chamber and kept at -40℃ for 30 minutes. Then, the temperature was switched to 150℃ within 10 seconds and kept at 150℃ for 30 minutes. This constituted one cycle, and a total of 100 cycles were performed. After the test, the surface was observed for warping and microcracks. The test results are shown in Table 2.

[0058] Table 2 Performance Test Results

[0059] As shown in Table 2: A comparison of Example 1 with Comparative Examples 1 and 2 shows that when the rheology modifier is lacking (Comparative Example 1) or when the rheology modifier is excessively deviated from the ratio (Comparative Examples 2 and 3), the internal residual stress of the material reaches as high as 2.89 MPa and 2.6 MPa, respectively. In contrast, the residual stress in Example 1 is only 1.1 MPa. In Comparative Example 2, the rheology modifier is insufficient to wet and disperse the high specific surface area nanofillers, leading to severe agglomeration of the fillers, a sharp increase in internal stress, and collapse of the thermally conductive network. In Comparative Example 3, the stress exceeds this range; excessive rheology modifier can over-isolate the nanoskeleton, increase interfacial thermal resistance, and cause microphase separation and surface precipitation defects under thermal shock. Furthermore, within this specific range, the nano-thermal conductive reinforcing agent, through its in-situ self-assembled continuous network, allows heat to be conducted at high speed along the phonon channels with extremely low interfacial thermal resistance, thus eliminating the need for massive amounts of fillers. During high-speed shearing, the rheology modifier functional groups coated on the surface of the nano-thermal conductive reinforcing agent undergo shear thinning, and the coating layer acts like microscopic "balls" to de-entangle and lubricate the fluid, significantly reducing the macroscopic viscosity of the melt and greatly reducing the residual stress of the finished product, thus preventing warping after 100 thermal shocks.

[0060] In traditional technologies, silicone rubber, flame-retardant ABS, and flexible TPE cannot use the same processing aid system due to their completely different polarities and molecular chains. However, the present invention (Examples 1, 2, and 3) maintains the melt flow rate (MFR) within an excellent processing window in three completely different matrices. This proves that the rheology modifier system unifies the shear viscosity performance of different matrices, achieving a breakthrough of "one formulation system suitable for multiple electronic rubber and plastic parts matrices".

[0061] Although Comparative Example 4 used the same matrix and rheology modifier as Example 1, its elongation at break after aging plummeted to 55.4% because the anti-aging additives were not formulated in the specific ratio of this invention. In contrast, Examples 1-3 all maintained an elongation at break above 85%. This is because the anti-aging additives and rheology modifiers formed a dense antioxidant / UV shielding coating at the network boundaries. This synergistic protection of the microstructure endows the composite material with an extremely long service life at high temperatures.

[0062] The above are merely preferred embodiments of the present invention and do not limit the patent scope of the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the patent protection scope of the present invention.

Claims

1. A composite material for rubber and plastic parts, characterized in that, The raw materials for the composite material used in rubber and plastic parts include the following parts by weight: The mixture comprises 100 parts of rubber and plastic matrix resin, 1-5 parts of nano thermally conductive reinforcing agent, 0.5-3 parts of rheology modifier, 1-4 parts of anti-aging additive, and 5-15 parts of functional filler, wherein the mass ratio of the nano thermally conductive reinforcing agent to the rheology modifier is 1:(0.2~0.8).

2. The composite material for rubber and plastic parts as described in claim 1, characterized in that, The rubber-plastic matrix resin is any one of modified silicone rubber, flame-retardant ABS, and soft TPE; and / or, The rheology modifier includes at least one of acrylate copolymers, maleic anhydride graft copolymers, and silicone-polyurethane copolymers; and / or, The functional filler includes at least one of micron-sized magnesium hydroxide, graphene-like kaolin, and hollow glass microspheres.

3. The composite material for rubber and plastic parts as described in claim 1, characterized in that, The nano-thermal conductive reinforcing agent is prepared from nano-reinforcing materials modified with silane coupling agents and inorganic rigid particles. The nano-reinforcing material includes at least one of carbon nanotubes, carbon nanofibers, and graphene; and / or, The inorganic rigid particles include at least one of nano-alumina, nano-silicon oxide, and nano-magnesium oxide.

4. The composite material for rubber and plastic parts as described in claim 3, characterized in that, The mass ratio of the inorganic rigid particles to the nano-reinforced materials is (3~25):

1.

5. The composite material for rubber and plastic parts as described in claim 1, characterized in that, The anti-aging additives include hindered amine light stabilizers and hindered phenolic antioxidants.

6. The composite material for rubber and plastic parts as described in claim 5, characterized in that, The mass ratio of the hindered amine light stabilizer to the hindered phenolic antioxidant is 1:(1~2.5); and / or, The hindered amine light stabilizer includes light stabilizer CyasorbUV-3346 or light stabilizer 944; and / or, The hindered phenolic antioxidants include antioxidant 1010.

7. The method for preparing the composite material for rubber and plastic parts according to any one of claims 1-6, characterized in that, Includes the following steps: S1. Premix the rubber and plastic matrix resin, rheology modifier and anti-aging additive to form a premix; S2. Mix the nano-thermal conductive reinforcing agent with the functional filler to obtain the composite filler; S3. The premixed material and the compound filler are injected into a twin-screw extruder, and after melt mixing and extrusion granulation, a composite material for rubber and plastic parts is obtained.

8. The composite material for rubber and plastic parts as described in claim 7, characterized in that, When the rubber-plastic matrix resin is modified silicone rubber, the melt flow rate of the composite material for rubber-plastic parts is 5~15 g / 10min within a processing window of 180℃~220℃; and / or, When the rubber and plastic matrix resin is flame-retardant ABS or soft TPE, the melt flow rate of the composite material for rubber and plastic parts is 10~25 g / 10min in the processing window of 200℃~230℃.

9. The method for preparing the composite material for rubber and plastic parts as described in claim 8, characterized in that, In step S3, the temperature of each zone of the twin-screw extruder ranges from 170°C to 230°C.

10. The application of a composite material for rubber and plastic parts as described in any one of claims 1-7, or a composite material for rubber and plastic parts prepared by the method described in claim 8 or 9, in industrial control equipment, new energy electronics, or precision consumer electronics.

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