Antistatic flame-retardant safety helmet material and preparation method thereof

Abstract

This application relates to the field of polymer materials, specifically disclosing an antistatic and flame-retardant safety helmet material and its preparation method. The antistatic and flame-retardant safety helmet material comprises the following raw materials in parts by weight: 100 parts ABS; 18-24 parts phosphorus-nitrogen-based halogen-free composite flame retardant; 8-12 parts polymeric permanent antistatic agent; 4-6 parts ABS-g-MAH; 0.5-0.8 parts heat stabilizer; 0.5-1 part lubricant; and 0.02-0.05 parts color modifier. The preparation method is as follows: stepwise premixing; melt extrusion. The antistatic and flame-retardant safety helmet material of this application achieves a balance between durable antistatic properties and halogen-free flame retardancy.

Description

Technical Field

[0001] This application relates to the field of polymer materials, and more specifically, to an antistatic and flame-retardant safety helmet material and its preparation method. Background Technology

[0002] Currently, various industries are continuously raising their technical requirements for personal protective equipment (PPE). Especially in high-risk work areas such as petrochemicals, coal mining, power systems, and fire rescue, safety helmets have been upgraded from basic labor protection supplies to decisive equipment for ensuring the safety of workers' lives.

[0003] Currently, mainstream safety helmet materials in the domestic market face multiple technical bottlenecks. While protective products based on traditional engineering plastics such as ABS and PC possess basic impact protection, they suffer from limitations in antistatic efficiency (surface resistivity is generally around 10). 12 ~10 14 There are significant shortcomings in key indicators such as flame retardancy (Ω) and flame retardancy (afterflame time generally exceeds 15 seconds).

[0004] At the technical level, traditional material modification schemes have significant structural defects. Short-term antistatic agents mainly function through surface migration, and their durability is significantly affected by environmental humidity; while carbon black-based antistatic agents, although long-lasting, severely limit the color diversity of products. Regarding flame retardant systems, halogenated flame retardants have been gradually phased out due to the release of toxic fumes, but the synergistic mechanism between phosphorus-nitrogen halogen-free flame retardants and antistatic components has not yet been fully explored, making it difficult to achieve a balance in the overall performance of materials.

[0005] Therefore, developing high-performance safety helmet materials that achieve a balance between antistatic durability and halogen-free flame retardancy has become the key to overcoming the bottleneck in the industry's development. Summary of the Invention

[0006] To achieve a balance between antistatic durability and halogen-free flame retardancy in safety helmet materials, this application provides an antistatic and flame-retardant safety helmet material and its preparation method.

[0007] In a first aspect, this application provides an antistatic and flame-retardant safety helmet material, which adopts the following technical solution: A static-resistant and flame-retardant safety helmet material, comprising the following raw materials in parts by weight: 100 ABS sheets; 18-24 parts of phosphorus-nitrogen-based halogen-free composite flame retardant; 8-12 parts of polymeric permanent antistatic agent; 4-6 parts of ABS-g-MAH; Heat stabilizer 0.5–0.8 parts; Lubricant 0.5 to 1 part; Color adjuster 0.02 to 0.05 parts.

[0008] By adopting the above technical solution, ABS-g-MAH is used as a compatibilizer, establishing a dual effect of "chemical bonding + physical anchoring" between the ABS substrate and functional additives, thus solving the performance degradation problem caused by additive migration and precipitation. The gas-phase / condensed-phase composite flame retardant pathway of the phosphorus-nitrogen-based halogen-free composite flame retardant forms a spatial complement with the bulk conductive network of the polymeric permanent antistatic agent, avoiding mutual interference. While replacing imported materials, performance stability is improved, material costs are reduced by 30%–40%, antistatic durability is significantly enhanced, and the cost-effectiveness is superior. The addition of color modifiers and heat stabilizers inhibits processing thermal degradation, controls color difference, and maintains the original color. While meeting flame retardant and antistatic requirements, the material's color change ΔE ≤ 1.5 is ensured, achieving a unity of aesthetics and function. Therefore, the effect of achieving a balance between antistatic durability and halogen-free flame retardancy in safety helmet materials is obtained.

[0009] Optionally, the phosphorus-nitrogen-based halogen-free composite flame retardant includes ammonium polyphosphate and melamine cyanurate, wherein the ammonium polyphosphate is present in 12-16 parts by weight and the melamine cyanurate is present in 6-8 parts by weight.

[0010] By employing the above technical solution, ammonium polyphosphate (APP) and melamine cyanurate (MCA) undergo a chemical reaction upon heating to generate phosphoric acid / polyphosphoric acid, catalyzing the decomposition of MCA and forming a denser expanded char layer. Simultaneously, the sublimation of MCA absorbs heat, lowering the material's surface temperature. When the two are compounded in a certain proportion, the flame retardant efficiency is significantly higher than that of a single component, and the amount added can be reduced, minimizing damage to mechanical properties.

[0011] ABS is a nonpolar or weakly polar polymer, while APP, MCA, and PEEA are all highly polar substances. Direct blending of these polymers can easily lead to phase separation. However, the maleic anhydride groups in the maleic anhydride-grafted polymer (ABS-g-MAH) can chemically react with the amino groups of APP to form covalent bonds. Simultaneously, the ABS backbone is completely compatible with the matrix. This dual effect of "chemical bonding + physical entanglement" firmly fixes the additives within the matrix, resulting in better interfacial compatibility control.

[0012] Optionally, the polymeric permanent antistatic agent is a polyether ester amide.

[0013] By adopting the above technical solution, the polyether ester amide antistatic agent (PEEA) contains hydrophilic polyether segments and hydrophobic polyamide / polyester segments. During melt blending, the hydrophobic segments are compatible with and anchored to the substrate (ABS), while the hydrophilic segments migrate to the material surface to form a "micro-layer conductive pathway," absorbing ambient moisture to form an ion-conductive layer. Unlike small molecule surfactants (which are easily washed away by water), polymeric permanent antistatic agents achieve permanent antistatic properties through molecular chain entanglement and the anchoring effect of compatibilizers. Traditional carbon black-based antistatic agents interfere with the charring process of flame retardants and cause the material to turn black; while polymeric permanent antistatic agents are light-colored or transparent, do not interfere with the expansion flame retardant reaction of APP / MCA, and their polyether segments can promote melt drip suppression during combustion (in conjunction with MCA), forming a "antistatic / flame retardant" spatial complementarity with the flame retardant system.

[0014] Optionally, the heat stabilizer is antioxidant 1010 and antioxidant 168.

[0015] Optionally, the helmet material further includes the following raw materials in parts by weight: 3-5 parts of thermoplastic polyurethane elastomer; 1-2 parts of ultrafine fully vulcanized powder silicone rubber; 3-5 parts of tetrane-shaped zinc oxide whiskers; EMA grafted with 2-3 parts of GMA; KH550 0.2-0.3 parts.

[0016] By adopting the above technical solution, a ternary synergistic toughening system of "ultrafine fully vulcanized powdered silicone rubber (UFPSiR) / thermoplastic polyurethane elastomer (TPU) / tetraneedle-shaped zinc oxide whiskers (T-ZnOw)" is constructed to form a ternary elastic network. The TPU and ABS exhibit certain compatibility, providing a solid foundation for the ternary system. In the initial impact stage, the thermoplastic polyurethane elastomer (TPU) acts as the main buffer phase, providing continuous elastomer energy absorption during large deformation. The soft segments undergo high elastic deformation under impact loads, uniformly dispersing the impact energy over a larger area; the hard segments form physical cross-linking points, converting mechanical energy into internal energy through strain-induced crystallization. In the impact propagation stage, ultrafine fully vulcanized powdered silicone rubber (UFPSiR) acts as an auxiliary buffer phase, with particles embedded in the micro-defect regions of the matrix, providing nanoscale point stress. It absorbs local stress concentration through its own elastic deformation, and its fully vulcanized cross-linked structure allows the particles to recover rapidly after deformation, improving the system's compression set performance. During the crack propagation stage, tetraneedle zinc oxide whiskers (T-ZnOw) serve as the main framework phase. The tetraneedle structure forms a three-dimensional network within the matrix, consuming crack propagation energy through crack deflection, bridging, and pull-out effects. While maintaining the triple functions of halogen-free flame retardancy, permanent antistatic properties, and color retention, a significant improvement in the material's impact resistance is achieved with a relatively low amount of toughening components added. EMA-grafted GMA acts as a reactive synergist, anchoring T-ZnOw and participating in TPU / ABS interface compatibilization. KH550 improves the interfacial bonding between UFPSiR and TPU / ABS.

[0017] Furthermore, the semiconductor properties of T-ZnOw create a three-dimensional conductive network, while PEEA forms a bulk conductive network, with this dual network ensuring durable antistatic properties. T-ZnOw and APP form a P / Zn synergy, promoting the formation of a dense carbon layer and improving flame retardant efficiency. T-ZnOw also releases active oxygen, providing highly efficient, broad-spectrum, and long-lasting antibacterial properties, adding health protection attributes to the helmet.

[0018] Optionally, the tetra-needle zinc oxide whiskers are surface modified with KH570 before use.

[0019] Secondly, this application provides a method for preparing an antistatic and flame-retardant safety helmet material, employing the following technical solution: A method for preparing an antistatic and flame-retardant safety helmet material includes the following steps: Stepwise premixing: Mix ABS and ABS-g-MAH until homogeneous; add a polymeric permanent antistatic agent and continue mixing until homogeneous; add a heat stabilizer, lubricant, and color modifier, and mix until homogeneous to obtain a homogeneous premix. Melt extrusion: Twin-screw melt blending, premixed material is fed into the main feed port, and phosphorus-nitrogen halogen-free composite flame retardant is fed into the side feed port in the later stage of the melting section. The feeding section temperature is 180℃, the melting section temperature is 200℃, the mixing section temperature is 210℃, dynamic crosslinking occurs, the exhaust section temperature is 200℃, the die head temperature is 195℃, the screw speed is 350rpm, extrusion, and granulation.

[0020] By adopting the above technical solution and constructing an integrated molding process of "stepwise addition - shear control - dynamic crosslinking", nanoscale dispersion and interface stabilization of additives in the substrate are achieved. By optimizing the temperature and shear field parameters of the twin-screw extruder, the particle size of the additive dispersion is controlled to ≤5μm, effectively avoiding color difference, performance fluctuation and stress concentration problems caused by agglomeration, and ensuring the performance consistency and yield of the material in large-scale production.

[0021] Thirdly, this application provides a method for preparing an antistatic and flame-retardant safety helmet material, using the following technical solution: A method for preparing an antistatic and flame-retardant safety helmet material includes the following steps: Stepwise premixing: Mix ABS and ABS-g-MAH until homogeneous; add polymeric permanent antistatic agent, EMA-grafted GMA, and thermoplastic polyurethane elastomer and continue mixing until homogeneous; add ultrafine fully vulcanized powdered silicone rubber and KH550 and continue mixing until homogeneous; add tetra-needle-shaped zinc oxide whiskers and continue mixing until homogeneous; add heat stabilizer, lubricant, and color modifier and mix until homogeneous to obtain a homogeneous premix. Melt extrusion: Twin-screw melt blending, premixed material is fed into the main feed port, and phosphorus-nitrogen halogen-free composite flame retardant is fed into the side feed port in the later stage of the melting section. The feeding section temperature is 180℃, the melting section temperature is 200℃, the mixing section temperature is 210℃, dynamic crosslinking occurs, the exhaust section temperature is 200℃, the die head temperature is 195℃, the screw speed is 350rpm, extrusion, and granulation.

[0022] In summary, this application has the following beneficial effects: 1. Because this application uses ABS-g-MAH as a compatibilizer, it establishes a dual effect of "chemical bonding + physical anchoring" between the ABS substrate and functional additives, solving the performance degradation problem caused by additive migration and precipitation. Utilizing the gas-phase / condensed-phase composite flame-retardant pathway of the phosphorus-nitrogen-based halogen-free composite flame retardant, it forms a spatial complement with the bulk conductive network of the polymeric permanent antistatic agent, avoiding mutual interference. While replacing imported materials, it improves performance stability, reduces material costs by 30%–40%, significantly enhances antistatic durability, and offers excellent cost-effectiveness. The addition of color modifiers and heat stabilizers inhibits processing thermal degradation, controls color difference, and maintains the original color. While meeting flame-retardant and antistatic requirements, it ensures that the material's color change ΔE ≤ 1.5, achieving a unity of aesthetics and function. Therefore, it achieves a unified effect of antistatic durability and halogen-free flame retardancy in safety helmet materials.

[0023] 2. In this application, the preferred method is to use a ternary synergistic toughening system of "ultra-fine fully vulcanized powder silicone rubber (UFPSiR) / thermoplastic polyurethane elastomer (TPU) / tetra-needle zinc oxide whiskers (T-ZnOw)" to construct a ternary elastic network. While maintaining the triple functions of halogen-free flame retardancy, permanent antistatic properties, and original color retention, the material's impact resistance is significantly improved with a relatively low amount of toughening component added.

[0024] 3. The method of this application achieves nanoscale dispersion and interface stabilization of additives in the substrate by constructing an integrated molding process of "stepwise addition-shear control-dynamic crosslinking". Detailed Implementation

[0025] The present application will be further described in detail below with reference to the embodiments. It should be noted that: unless otherwise specified, the conditions in the following embodiments shall be performed under conventional conditions or conditions recommended by the manufacturer, and the raw materials used in the following embodiments shall be commercially available unless otherwise specified.

[0026] ABS, brand name PetroChina Jilin Chemical, 0215A.

[0027] Ammonium polyphosphate (APP), purchased from Zhenjiang Xingxing Flame Retardant Co., Ltd., high degree of polymerization APP-1.

[0028] Melamine cyanurate (MCA) was purchased from Jiangsu Congzhong Chemical Co., Ltd.

[0029] Polyether ester amide (PEEA), purchased from Hangshi Technology Development (Hangzhou) Co., Ltd., model GF-103.

[0030] Thermoplastic polyurethane elastomer (TPU), BASF.

[0031] Ultrafine fully vulcanized powdered silicone rubber (UFPSiR), Sinopec Beijing Chemical Research Institute, grade VP-601, particle size 100nm.

[0032] Four needle-shaped zinc oxide whiskers (T-ZnOw) were purchased from Chengdu Tianyou Jingchuang Technology Co., Ltd., model JC-01.

[0033] Example Example 1 An antistatic and flame-retardant safety helmet material comprises the following raw materials: ABS; phosphorus-nitrogen-based halogen-free composite flame retardant, including ammonium polyphosphate (APP) and melamine cyanurate (MCA); a polymeric permanent antistatic agent, polyether ester amide (PEEA); ABS-g-MAH; heat stabilizers, including antioxidant 1010 and antioxidant 168; a lubricant, ethylene bis-stearamide (EBS); and a color modifier, fluorescent whitening agent OB-1. The dosage of each raw material is detailed in Table 1.

[0034] A method for preparing an antistatic and flame-retardant safety helmet material includes the following steps: Stepwise premixing: Mix ABS and ABS-g-MAH at 500 rpm until homogeneous; add a polymeric permanent antistatic agent and stir at 500 rpm until homogeneous; add a heat stabilizer, lubricant, and color modifier and stir at 1500 rpm until homogeneous to obtain a homogeneous premix. Melt extrusion: Twin-screw melt blending, premixed material is fed into the main feed port, and a phosphorus-nitrogen-based halogen-free composite flame retardant is fed into the side feed port in the later stage of the melting section. The feeding section temperature is 180℃, the melting section temperature is 200℃, the mixing section temperature is 210℃, dynamic crosslinking occurs, the exhaust section temperature is 200℃, the die head temperature is 195℃, and the screw speed is 350 rpm. The length of the melting and mixing sections together accounts for 46% of the total screw working length. The melt pressure is 2 MPa. Extrusion is performed, followed by water-cooled granulation at 30℃ to a particle size of 3 mm. 3mm.

[0035] Example 2 The difference between this embodiment and Embodiment 1 is that the amount of each raw material used is different, as detailed in Table 1.

[0036] Example 3 The difference between this embodiment and Embodiment 1 is that the amount of each raw material used is different, as detailed in Table 1.

[0037] Example 4 An antistatic and flame-retardant safety helmet material comprises the following raw materials: ABS; phosphorus-nitrogen halogen-free composite flame retardant, including ammonium polyphosphate (APP) and melamine cyanurate (MCA); a polymeric permanent antistatic agent, polyether ester amide (PEEA); ABS-g-MAH; heat stabilizers, including antioxidant 1010 and antioxidant 168; a lubricant, ethylene bis-stearamide (EBS); a color modifier, fluorescent whitening agent OB-1; thermoplastic polyurethane elastomer (TPU); ultrafine fully vulcanized powder silicone rubber (UFPSiR); tetraneedle-shaped zinc oxide whiskers (T-ZnOw); EMA-grafted GMA (EMA-GMA); and KH550. The dosage of each raw material is detailed in Table 1.

[0038] A method for preparing an antistatic and flame-retardant safety helmet material includes the following steps: Raw material pretreatment: The tetra-needle-shaped zinc oxide whiskers were surface-modified with KH570. T-ZnOw was dried at 80℃ for 2 hours using forced air drying. A KH570 ethanol solution was prepared (KH570 was used at 5% of the mass of T-ZnOw, diluted to a 20wt% ethanol solution). The dried T-ZnOw was added to a high-speed mixer and stirred at 70℃. The KH570 ethanol solution was slowly added dropwise, and the mixture was stirred for 50 minutes. The mixture was then dried at 80℃ for 2 hours to obtain surface-organically modified T-ZnOw.

[0039] Stepwise premixing: Mix ABS and ABS-g-MAH until homogeneous; add polymeric permanent antistatic agent, EMA-grafted GMA, and thermoplastic polyurethane elastomer and continue mixing until homogeneous; add ultrafine fully vulcanized powdered silicone rubber and KH550 (diluted to 20wt% ethanol solution) and continue mixing until homogeneous; add tetra-needle-shaped zinc oxide whiskers and continue mixing until homogeneous; add heat stabilizer, lubricant, and color modifier and mix until homogeneous to obtain a homogeneous premix. Melt extrusion: Twin-screw melt blending, premixed material is fed into the main feed port, and a phosphorus-nitrogen-based halogen-free composite flame retardant is fed into the side feed port in the later stage of the melting section. The feeding section temperature is 180℃, the melting section temperature is 200℃, the mixing section temperature is 210℃, dynamic crosslinking occurs, the exhaust section temperature is 200℃, the die head temperature is 195℃, and the screw speed is 350 rpm. The length of the melting and mixing sections together accounts for 46% of the total screw working length. The melt pressure is 2 MPa. Extrusion is performed, followed by water-cooled granulation at 30℃ to a particle size of 3 mm. 3mm.

[0040] Example 5 The difference between this embodiment and Embodiment 4 is that the amount of each raw material used is different, as detailed in Table 1.

[0041] Example 6 The difference between this embodiment and Embodiment 4 is that the amount of each raw material used is different, as detailed in Table 1.

[0042] Example 7 The difference between this embodiment and embodiment 5 is that this embodiment does not have tetra-needle zinc oxide whiskers and EMA-grafted GMA.

[0043] Example 8 The difference between this embodiment and embodiment 5 is that this embodiment does not contain ultrafine fully vulcanized powder silicone rubber and KH550.

[0044] Example 9 The difference between this embodiment and Embodiment 5 is that this embodiment does not contain thermoplastic polyurethane elastomer.

[0045] Table 1 Raw material usage amounts for each embodiment Comparative Example Comparative Example 1 A safety helmet material comprises the following raw materials: 100 kg of ABS; 28 kg of flame retardant decabromodiphenyl ether; 10 kg of antistatic agent carbon black; 0.7 kg of calcium stearate; and 0.3 kg of BHT antioxidant.

[0046] A method for preparing a safety helmet material includes the following steps: mixing all raw materials at 1500 rpm until homogeneous to obtain a premix; extruding the premix through a twin-screw extruder, with all materials added from the main feed port, the feeding section temperature being 180°C, the melting section 200°C, the mixing section 210°C, the die head 195°C, and the screw speed 350 rpm; and then water-cooling and granulating at 30°C to achieve a particle size of 3 mm. 3mm.

[0047] Comparative Example 2 The difference between this comparative example and Example 2 is that this comparative example does not contain ABS-g-MAH.

[0048] Comparative Example 3 The difference between this comparative example and Example 2 is that the flame retardant used in this example is ammonium polyphosphate, and the amount added is 28 kg.

[0049] Comparative Example 4 The difference between this comparative example and Example 2 is that the flame retardant used in this example is melamine cyanurate, and the amount added is 28 kg.

[0050] Comparative Example 5 The difference between this comparative example and Example 2 is that the flame retardant used is decabromodiphenyl ether.

[0051] Comparative Example 6 The difference between this comparative example and Example 2 is that the antistatic agent is carbon black.

[0052] Comparative Example 7 The difference between this comparative example and Example 2 is that the raw materials were not premixed step by step, and the flame retardant was not fed separately; all raw materials were mixed together.

[0053] Performance testing Detection methods The safety helmet materials prepared in the above embodiments and comparative examples were respectively subjected to safety helmet injection molding. The screw length-to-diameter ratio was 25, the barrel rear section temperature was 200℃, the barrel middle section temperature was 210℃, the barrel front section temperature was 205℃, the nozzle temperature was 210℃, the mold temperature was 60℃, the injection pressure was 100MPa, the holding pressure was 70MPa, the holding time was 3s, the back pressure was 8MPa, the injection speed was 50mm / s, the cooling time was 30s, the screw speed was 70rpm, and the mold was a special mold for safety helmets (with a brim, shell, and reinforcing rib structure) designed according to GB 2811.

[0054] Referring to "GB 2811-2019 Head Protection Safety Helmet", the flame retardant performance, antistatic performance (surface resistance) and impact absorption performance of the above-mentioned injection molded safety helmets were tested. The test results are detailed in Table 2.

[0055] Referring to "GB / T 8629-2017 'Domestic Washing and Drying Procedures for Testing Textiles'", the above-mentioned injection-molded safety helmets were washed using the 4A procedure for 100 gentle washes at a water temperature of 40℃, followed by tumble drying at 50℃±5℃ for 1 hour. After standing for 24 hours, the antistatic properties (surface resistance) were tested to demonstrate the durability of the antistatic properties. The test results are detailed in Table 2.

[0056] Samples were taken from the helmet shell and their color performance was tested using a colorimeter; the lightness (L) was measured. See Table 2 for details. The lightness measured for the ABS base material is 90.3. The closer the lightness is to 90.3, the closer the helmet material is to its natural color.

[0057] Table 2 Test Results As can be seen from Examples 1-3 and Comparative Example 1, and Table 2, the safety helmet material prepared by the technical solution of this application has effectively improved the natural color performance, flame retardant performance, antistatic performance and impact absorption performance of the safety helmet after injection molding.

[0058] As can be seen from the gradient experiments in Examples 1 to 3, with the optimization of the ratio of ammonium polyphosphate (APP) / melamine cyanurate (MCA) flame retardant system and the increase of the amount of antioxidant / fluorescent whitening agent (OB-1), the flame retardant performance and color retention of the material are gradually enhanced.

[0059] In terms of flame retardant performance, the combination of APP and MCA forms a typical phosphorus-nitrogen synergistic effect. APP acts as an acid source to promote the char formation of the substrate, while MCA acts as a gas source to release non-combustible gases to dilute combustibles. The combination of the two reduces the afterflame time from 10-16 seconds for a single component to 1.5-2.0 seconds, with no dripping and a smaller total amount added, demonstrating a synergistic effect of "1+1>2".

[0060] Regarding antistatic properties, Examples 4-6 show a significant improvement in antistatic performance after introducing tetra-needle zinc oxide whiskers (T-ZnOw) onto the PEEA base. This is because T-ZnOw itself is a semiconductor material, and its three-dimensional tetra-needle structure interlocks in the matrix to form additional conductive pathways, creating a dual conductive mechanism with the bulk conductive network of PEEA. The two complement each other, resulting in superior and more durable antistatic performance.

[0061] Regarding toughening performance, Example 3 showed the best performance (afterburning 1.5s, L... =90.0), but considering production costs and practical application needs, toughening components need to be added for toughening. In order to reduce the impact of TPU yellowing on the original color performance, the intermediate scheme between Example 2 and Example 3—that is, the antioxidant / OB-1 is used in a medium to high amount and the APP / MCA ratio is 15 / 7—was selected as the optimal basic formula, and a toughening system was further introduced on this basis. The head mold impact force of Example 5 was only 1980 N, which was 40% lower than the basic formula without toughening. To verify the synergistic effect, Examples 7 to 9 were designed with different components missing: Example 7 (without T-ZnOw) impact force 2850 N, Example 8 (without UFPSiR) impact force 2680 N, Example 9 (without TPU) impact force 2980 N. All three were significantly worse than Example 5, proving that TPU, UFPSiR and T-ZnOw are indispensable. The synergistic mechanism is as follows: TPU absorbs energy through large deformation elastic energy storage in the initial stage of impact; UFPSiR, as a nanopowder, disperses local stress and reduces permanent compression deformation; the four needle-like three-dimensional structure of T-ZnOw further hinders crack propagation through pull-out effect and crack deflection during crack propagation, and the three form a "spatiotemporal relay" toughening network.

[0062] Regarding color retention, Examples 4-6 containing TPU successfully suppressed thermal oxidative yellowing of TPU through high dosages of antioxidants and OB-1. The colorimetric index reached 89.5–90.0, which is on par with the basic formulation without TPU and far superior to Examples 1 and 2 with low antioxidant content. This demonstrates that the end-to-end color management solution can effectively solve the yellowing problem caused by TPU toughening.

[0063] The comparative results further corroborated the necessity of the key components: Comparative Example 2, lacking compatibilizer, exhibited extremely poor impact resistance; Comparative Examples 3 and 4, being single-component flame retardants, failed to pass after 10-16 seconds of afterflame retardation; Comparative Examples 5 and 6, containing halogenated flame retardants or carbon black antistatic agents, suffered from issues such as dripping or the inability to achieve the desired black color. Comparative Example 7 also demonstrated certain disadvantages in its process.

[0064] In summary, this application, through a reasonable raw material compounding design, fully leverages the synergistic effects of APP / MCA phosphorus-nitrogen flame retardancy, PEEA / T-ZnOw dual conductive network, TPU / UFPSiR / T-ZnOw ternary spatiotemporal toughening, and antioxidant / OB-1 color management. The overall performance of Example 5 is far superior to all comparative examples, and the cost is controllable, providing the safety helmet industry with a high-performance, environmentally friendly, and multi-colorable modified material solution.

[0065] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. An antistatic, flame resistant safety hat material characterized in that, Including the following parts by weight of raw materials: 100 ABS sheets; 18-24 parts of phosphorus-nitrogen-based halogen-free composite flame retardant; 8-12 parts of polymeric permanent antistatic agent; 4-6 parts of ABS-g-MAH; Heat stabilizer 0.5–0.8 parts; Lubricant 0.5 to 1 part; Color adjuster 0.02 to 0.05 parts.

2. The antistatic flame resistant safety hat material of claim 1, wherein: The phosphorus-nitrogen-based halogen-free composite flame retardant includes ammonium polyphosphate and melamine cyanurate, wherein the ammonium polyphosphate is present in 12-16 parts by weight and the melamine cyanurate is present in 6-8 parts by weight.

3. The antistatic, flame-resistant safety hat material of claim 1, wherein: The polymeric permanent antistatic agent is polyether ester amide.

4. The antistatic, flame-resistant safety hat material of claim 1, wherein: The heat stabilizers are antioxidant 1010 and antioxidant 168.

5. The antistatic, flame-resistant safety hat material according to claim 1, wherein: The helmet material also includes the following raw materials in parts by weight: 3-5 parts of thermoplastic polyurethane elastomer; 1-2 parts of ultrafine fully vulcanized powder silicone rubber; 3-5 parts of tetrane-shaped zinc oxide whiskers; EMA grafted with 2-3 parts of GMA; KH550 0.2-0.3 parts.

6. An antistatic, flame resistant safety hat material according to claim 5, characterized in that: The four needle-shaped zinc oxide whiskers were surface modified with KH570 before use.

7. A method for preparing an antistatic and flame-retardant safety helmet material according to any one of claims 1 to 4, characterized in that, Includes the following steps: Stepwise premixing: Mix ABS and ABS-g-MAH until homogeneous; add a polymeric permanent antistatic agent and continue mixing until homogeneous; add a heat stabilizer, lubricant, and color modifier, and mix until homogeneous to obtain a homogeneous premix. Melt extrusion: Twin-screw melt blending, premixed material is fed into the main feed port, and phosphorus-nitrogen halogen-free composite flame retardant is fed into the side feed port in the later stage of the melting section. The feeding section temperature is 180℃, the melting section temperature is 200℃, the mixing section temperature is 210℃, dynamic crosslinking occurs, the exhaust section temperature is 200℃, the die head temperature is 195℃, the screw speed is 350rpm, extrusion, and granulation.

8. A method for preparing an antistatic and flame-retardant safety helmet material according to claim 5 or 6, characterized in that, Includes the following steps: Stepwise premixing: Mix ABS and ABS-g-MAH until homogeneous; add polymeric permanent antistatic agent, EMA-grafted GMA, and thermoplastic polyurethane elastomer and continue mixing until homogeneous; add ultrafine fully vulcanized powdered silicone rubber and KH550 and continue mixing until homogeneous; add tetra-needle-shaped zinc oxide whiskers and continue mixing until homogeneous; add heat stabilizer, lubricant, and color modifier and mix until homogeneous to obtain a homogeneous premix. Melt extrusion: Twin-screw melt blending, premixed material is fed into the main feed port, and phosphorus-nitrogen halogen-free composite flame retardant is fed into the side feed port in the later stage of the melting section. The feeding section temperature is 180℃, the melting section temperature is 200℃, the mixing section temperature is 210℃, dynamic crosslinking occurs, the exhaust section temperature is 200℃, the die head temperature is 195℃, the screw speed is 350rpm, extrusion, and granulation.

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