A polystyrene material and its preparation method and application

Abstract

The present invention belongs to the field of polymer materials technology, specifically relating to a polystyrene material, its preparation method, and application. The polystyrene material comprises the following components, in parts by weight: 10-50 parts high-impact polystyrene resin, 25-40 parts polyphenylene ether resin, 10-20 parts phosphate flame retardant, 5-15 parts flame retardant synergist, 1-20 parts toughening agent, and 0.1-0.5 parts anti-drip agent. The high-impact polystyrene resin has a melt flow index of 3-10 g / 10 min at 200°C and 5 kg; and the polyphenylene ether resin has an intrinsic viscosity of 0.40 dL / g to 0.60 dL / g. The polystyrene material produced by the present invention effectively overcomes the poor toughness of existing halogen-free HIPS materials, achieving high flame retardancy and notched impact strength.

Description

Technical Field

[0001] The present invention belongs to the technical field of polymer materials, and in particular relates to a polystyrene material and a preparation method and application thereof. Background Art

[0002] High-impact polystyrene (HIPS) is produced by adding a small amount of elastomer to PS. It overcomes the brittleness of polystyrene and exhibits excellent impact toughness and processability, making it widely used in industries such as electronics, automobiles, home appliances, instruments, daily necessities, and toys. However, HIPS is flammable, and currently, brominated flame retardants are commonly used to prepare flame-retardant HIPS materials. Commonly used brominated flame retardants include tetrabromobisphenol A, decabromodiphenylethane, 2,4,6-tribromotriphenoxy-1,3,5-triazine, and brominated epoxy oligomers. The combustion products of halogenated flame-retardant resins are generally considered to contain highly toxic substances that are harmful to the environment and humans.

[0003] High-impact polystyrene resin has an oxygen index of only 18.0, making it difficult to form carbon on its own. To achieve halogen-free flame retardancy, it is necessary to improve the system's carbonization efficiency and achieve condensed-phase flame retardancy. Adding polyphenylene ether resin to a phosphate-based halogen-free flame retardant can significantly improve the material's carbonization efficiency and thus achieve flame retardancy. However, the significant plasticizing effect of the large amount of phosphate-based flame retardant added reduces the material's melt strength and makes it prone to burn-through, making it difficult to pass the 5VA high-level flame retardancy test.

[0004] To address the material's easy burn-through problem, common improvement methods include adding large amounts of mineral powder fillers or glass fiber to form a skeletal support, improving the square plate's resistance to burn-through, or excessively increasing the flame retardant content to achieve rapid flame retardancy and prevent burn-through. However, these methods increase costs, and the addition of large amounts of fillers or flame retardants also reduces impact strength, limiting the material's application. Patent document CN112321947A describes a 5VA-grade halogen-free flame-retardant polypropylene material. By adding glass powder, flake fillers, and needle-shaped fillers to form a stable ceramic structure, the material increases the thickness and density of the carbon layer, resolves the perforation problem in the 5VA square plate test, and passes the 5VA test. The addition of fillers not only affects the material's appearance but also significantly reduces its impact strength. Patent document CN202011520636 describes a flame-retardant, high-rigidity ACS composite material. This utilizes continuous long glass fibers in synergistic interaction with specific flame retardants and flame retardant synergists, and regulates the glass fiber retention length D90 in the composite material, significantly improving the flame retardancy and rigidity of the ACS composite material, achieving a flame retardancy rating of 5VA or higher. However, the material is prone to floating fibers on the surface, affecting its appearance. Summary of the Invention

[0005] The present invention aims to provide a polystyrene material, a preparation method thereof, and an application thereof. The polystyrene material prepared by the present invention can effectively solve the defect of poor toughness of existing halogen-free HIPS materials and achieve higher flame retardancy and notched impact strength.

[0006] In order to achieve the above object, the present invention adopts the following technical solution: a polystyrene material, comprising the following components in parts by weight: 10-50 parts of high-impact polystyrene resin, 25-40 parts of polyphenylene ether resin, 10-20 parts of phosphate flame retardant, 5-15 parts of flame retardant synergist, 1-20 parts of toughening agent, and 0.1-0.5 parts of anti-dripping agent;

[0007] The melt flow index of the high-impact polystyrene resin at 200° C. and 5 kg is 3-10 g / 10 min; the test standard for the melt flow index is “GB / T3682.1-2018 Determination of mass flow rate and melt volume flow rate of thermoplastic melts”;

[0008] The intrinsic viscosity of the polyphenylene ether resin is 0.40 dL / g to 0.60 dL / g. The intrinsic viscosity is measured according to the intrinsic viscosity method in GB / T41874-2022 Plastic Polyphenylene Ether (PPE) Resin.

[0009] The present invention utilizes a low-flow, high-impact polystyrene resin, which improves the material's melt strength, enhancing the spline's resistance to dripping and the square plate's resistance to burnthrough. A high-intrinsic-viscosity polyphenylene ether resin is selected, which significantly increases the material's melt strength during combustion, thereby resisting shrinkage perforation. The present invention utilizes a specific low-flow, high-impact polystyrene resin and a high-intrinsic-viscosity polyphenylene ether resin in synergy. The resulting polystyrene material meets the requirements of a thin 2mm square plate with no burnthrough and a 2mm spline with no dripping in the 5VA test, while also exhibiting high notched impact strength.

[0010] Preferably, the polystyrene material comprises the following components in parts by weight: 30-40 parts of high impact polystyrene resin, 30-35 parts of polyphenylene ether resin, 15-18 parts of phosphate flame retardant, 8-10 parts of flame retardant synergist, 5-15 parts of toughening agent, and 0.2-0.3 parts of anti-dripping agent.

[0011] Preferably, the high impact polystyrene resin has a melt flow index of 3-5 g / 10 min at 200° C. and 5 kg.

[0012] Preferably, the intrinsic viscosity of the polyphenylene ether resin is 0.45 dL / g to 0.55 dL / g.

[0013] Preferably, the phosphate flame retardant includes one or more of 2,2'-diphenylene propane tetraphenyl bisphosphate (BDP), m-phenylene tetraphenyl bisphosphate (RDP), hydroquinone bis(diphenyl phosphate), 1,4-benzene tetraphenyl ester or triphenyl phosphate (TPP).

[0014] Preferably, the flame retardant synergist includes one or more of melamine cyanurate, melamine polyphosphate, and aluminum diethylphosphinate.

[0015] The flame retardant synergist introduced in this invention not only promotes carbonization in the system and increases the carbonization rate, but also effectively protects the substrate from combustion. Furthermore, the inclusion of the flame retardant synergist significantly reduces the amount of phosphate flame retardant used, thereby reducing the plasticization effect of the flame retardant and improving the melt strength of the system. The selected flame retardant synergist exhibits excellent temperature resistance, thus maintaining high flame retardancy without decomposition during high-temperature processing.

[0016] Preferably, the toughening agent includes one or more of styrene-butadiene-styrene block copolymer, hydrogenated styrene-butadiene-styrene block copolymer, styrene-isoprene-styrene block copolymer, and styrene-butadiene random copolymer.

[0017] Preferably, the number average molecular weight of the toughening agent is between 100,000 and 300,000.

[0018] More preferably, the number average molecular weight of the toughening agent is between 150,000 and 300,000.

[0019] The present invention utilizes a high-molecular-weight toughening agent. This higher molecular weight not only significantly improves the toughening efficiency of the system but also enhances the material's melt strength, thereby improving burn-through resistance. The toughening agents all contain a styrene structure, resulting in improved compatibility with high-impact polystyrene and higher toughening efficiency.

[0020] Preferably, the anti-drip agent comprises polytetrafluoroethylene.

[0021] More preferably, the anti-dripping agent is polytetrafluoroethylene coated with SAN, and the effective content of polytetrafluoroethylene is 50-80%.

[0022] The anti-dripping agent coated with styrene-acrylonitrile copolymer is used in the present invention, which can improve the dispersion and anti-melting dripping effect of the anti-dripping agent.

[0023] Preferably, the polystyrene material further comprises additives in an amount of 0.5-5% of the total mass of the polystyrene material.

[0024] Preferably, the additive includes at least one of an antioxidant, a weathering agent, an antistatic agent, and a colorant.

[0025] Components commonly used in this field, such as antioxidants, weathering agents, antistatic agents, and colorants, can all be applied in the present invention.

[0026] The present invention also claims a method for preparing the polystyrene material, comprising the following steps:

[0027] All the ingredients are mixed and pelletized through extrusion to obtain the polystyrene material.

[0028] Preferably, the rotation speed of the extrusion granulation is 300-500 rpm.

[0029] Preferably, the temperature of zone 1 of the extrusion granulation is 80-100°C, the temperature of zone 2 is 240-250°C, the temperature of zone 3 is 240-250°C, the temperature of zone 4 is 230-240°C, the temperature of zone 5 is 230-240°C, the temperature of zone 6 is 230-240°C, the temperature of zone 7 is 230-240°C, the temperature of zone 8 is 230-240°C, the temperature of zone 9 is 240-250°C, and the temperature of the die head is 240-250°C.

[0030] The present invention also claims protection for a use of the polystyrene material in preparing a flame retardant material, which includes an electric control box, a junction box, a switch panel light, etc. of a household appliance or an electronic appliance.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] The polystyrene material prepared by the present invention can achieve halogen-free flame retardant V-0 performance, and can meet the requirements of not burning through a thinner 2mm square plate in a 5VA test, not dripping a 2mm sample strip, and having high notched impact strength. DETAILED DESCRIPTION

[0033] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0034] In the Examples and Comparative Examples, the experimental methods used are conventional methods unless otherwise specified, and the materials and reagents used are commercially available unless otherwise specified.

[0035] The raw materials used in the examples and comparative examples are shown in Table 1.

[0036] Table 1

[0037]

[0038]

[0039] Examples 1 to 13 and Comparative Examples 1 to 9

[0040] The components and weight proportions of the polystyrene materials of Examples 1 to 13 and Comparative Examples 1 to 9 are shown in Tables 2 to 3.

[0041] The preparation method of the polystyrene materials of Examples 1 to 13 and Comparative Examples 1 to 9 comprises the following steps:

[0042] A high-impact polystyrene resin, polyphenylene ether, a phosphate flame retardant, a flame retardant synergist, a toughening agent and an anti-dripping agent are put into a mixer and mixed evenly, and then extruded into granules through an extruder (the screw speed is 300-500 rpm, and the temperatures of the screw sections of the extruder from the feed port to the die are set to: zone 1 temperature 80-100° C., zone 2 temperature 240-250° C., zone 3 temperature 240-250° C., zone 4 temperature 230-240° C., zone 5 temperature 230-240° C., zone 6 temperature 230-240° C., zone 7 temperature 230-240° C., zone 8 temperature 230-240° C., zone 9 temperature 240-250° C., and die head temperature 240-250° C.) to obtain a high-impact polystyrene material.

[0043] Table 2 Component dosage (parts by weight)

[0044]

[0045]

[0046] Table 3 Component dosage in comparative example (parts by weight)

[0047]

[0048] Performance Testing

[0049] The polystyrene materials obtained in the examples and comparative examples were subjected to the following tests:

[0050] (1) Number of flames applied to a 2mm standard strip: Test the 2mm standard strip according to the UL94-2018 5V combustion requirements and record the number of flames applied until the strip fails. According to the 5VA rating requirements, the number of flames applied should be ≥5;

[0051] (2) Number of flames applied to a 2mm square plate: Test a 2mm standard sample plate according to the UL94-2018 5V combustion requirements and record the number of flames applied when the sample fails. According to the 5VA grade requirements, the number of flames applied should be ≥5;

[0052] (3) 2mm vertical burning: According to the UL94-2018 standard, the vertical burning test of 2mm specimens should meet the V-0 grade requirements;

[0053] (3) Izod notch impact strength: Tested in accordance with GB1843-1996 "Plastic Izod Impact Test Method", with a pendulum energy of 2.75 J and tested at room temperature. In order to obtain higher toughness, the notch impact strength of the material should be ≥10KJ / m 2 .

[0054] The performance test results are shown in Table 4.

[0055] Table 4

[0056]

[0057]

[0058] The data in Table 4 show that the polystyrene material prepared in this embodiment of the present invention has good flame retardancy, can stably pass the 2mm 5VA test, and meets the 2mm V-0 rating. It also has high toughness and good fluidity. This achieves the preparation of a halogen-free, flame-retardant, high-impact polystyrene material with a high flame retardancy. The number of times the flame is applied to a 2mm strip and a 2mm square plate can both be maintained at more than 5 times, meeting the 5VA rating requirements; the notched impact strength can be maintained at 10 kJ / m 2 Above, the melt flow index can be maintained above 20g / 10min.

[0059] In Comparative Example 1, the melt flow index of the HIPS resin selected was not suitable, and the burn-through resistance of the obtained polystyrene material square plate deteriorated and it was difficult to pass 5VA; in Comparative Example 2, the intrinsic viscosity of the PPE selected was not suitable, and the drip resistance of the obtained spline and the burn-through resistance of the square plate deteriorated and could not reach 5VA; in Comparative Example 3, the weight of the HIPS resin added was not suitable, and the flame retardant properties of the obtained polystyrene material deteriorated; in Comparative Example 4, the weight of the PPE resin added was not suitable, and the obtained polystyrene material The impact strength was low and the fluidity was poor. In Comparative Example 5, no flame retardant synergist was added, resulting in poor flame retardancy of the resulting polystyrene material. In Comparative Example 6, the weight of the flame retardant synergist was inappropriate, resulting in low impact strength and poor fluidity. In Comparative Example 7, no anti-drip agent was added, resulting in very poor anti-drip resistance of the resulting polystyrene strips, failing to pass 5VA and dripping even during vertical combustion, with a rating of only V-2. In Comparative Example 8, the amount of anti-drip agent added was inappropriate, resulting in the square plate easily shrinking and perforating, failing to achieve 5VA. In Comparative Example 9, the PPE content was too low, resulting in poor flame retardancy of the resulting polystyrene material.

[0060] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the present invention. Anyone skilled in the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by one of ordinary skill in the art without departing from the spirit and technical principles disclosed herein are intended to be covered by the claims of the present invention.

Claims

1. A polystyrene material, characterized in that: The invention comprises the following components in parts by weight: 10-50 parts of high-impact polystyrene resin, 25-40 parts of polyphenylene ether resin, 10-20 parts of phosphate flame retardant, 5-15 parts of flame retardant synergist, 1-20 parts of toughening agent, and 0.1-0.5 parts of anti-dripping agent; The high-impact polystyrene resin has a melt flow index of 3-10 g / 10 min at 200° C. and 5 kg; The intrinsic viscosity of the polyphenylene ether resin is 0.40 dL / g to 0.60 dL / g.

2. The polystyrene material according to claim 1, wherein: The invention comprises the following components in parts by weight: 30-40 parts of high-impact polystyrene resin, 30-35 parts of polyphenylene ether resin, 15-18 parts of phosphate flame retardant, 8-10 parts of flame retardant synergist, 5-15 parts of toughening agent and 0.2-0.3 parts of anti-dripping agent.

3. The polystyrene material according to claim 1, wherein: At least one of the following (1) to (2): (1) The high-impact polystyrene resin has a melt flow index of 3-5 g / 10 min at 200° C. and 5 kg; (2) The intrinsic viscosity of the polyphenylene ether resin is 0.45 dL / g to 0.55 dL / g.

4. The polystyrene material according to claim 1, wherein: At least one of the following (1) to (4): (1) The phosphate flame retardant includes one or more of 2,2'-diphenylene propane tetraphenyl bisphosphate, m-phenylene tetraphenyl bisphosphate, hydroquinone bis(diphenyl phosphate) or triphenyl phosphate; (2) The flame retardant synergist includes one or more of melamine cyanurate, melamine polyphosphate, and diethyl phosphinate aluminum; (3) The toughening agent includes one or more of styrene-butadiene-styrene block copolymer, hydrogenated styrene-butadiene-styrene block copolymer, styrene-isoprene-styrene block copolymer, and styrene-butadiene random copolymer; (4) The anti-dripping agent includes polytetrafluoroethylene.

5. The polystyrene material according to claim 4, wherein: The number average molecular weight of the toughening agent is 100,000-300,000.

6. The polystyrene material according to claim 1, wherein: The invention also includes additives in an amount of 0.5-5% by weight of the total weight of the polystyrene material.

7. The polystyrene material according to claim 6, wherein: The additives include at least one of an antioxidant, a weathering agent, an antistatic agent, and a colorant.

8. A method for preparing the polystyrene material according to any one of claims 1 to 7, characterized in that: The following steps are involved: The components of the polystyrene material according to any one of claims 1 to 7 are mixed and subjected to extrusion granulation to obtain the polystyrene material.

9. The preparation method according to claim 8, wherein At least one of the following (1) to (2): (1) The rotation speed of the extrusion granulation is 300-500 rpm; (2) The temperature of zone 1 of the extrusion granulation is 80-100°C, the temperature of zone 2 is 240-250°C, the temperature of zone 3 is 240-250°C, the temperature of zone 4 is 230-240°C, the temperature of zone 5 is 230-240°C, the temperature of zone 6 is 230-240°C, the temperature of zone 7 is 230-240°C, the temperature of zone 8 is 230-240°C, the temperature of zone 9 is 240-250°C, and the temperature of the die head is 240-250°C.

10. Use of the polystyrene material according to any one of claims 1 to 7 in the preparation of flame retardant materials.

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