Hypophosphite flame-retardant PPS composite material, preparation method and application thereof

Abstract

The application discloses a hypophosphite flame-retardant PPS composite material and a preparation method and application thereof, and relates to the technical field of polyphenylene sulfide composite materials.The application provides a hypophosphite flame-retardant PPS composite material, which comprises the following components in parts by weight: PPS resin 50-90 parts, glass fiber 10-50 parts, styrene thermoplastic elastomer 1-10 parts, hypophosphite flame retardant 4-8 parts, and phosphate 0.5-3 parts.The hypophosphite flame-retardant PPS composite material with high flame retardancy, high toughness and electric leakage tracking resistance is prepared through the synergy of the PPS resin, the styrene thermoplastic elastomer, the hypophosphite flame retardant and the phosphate.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of polyphenylene sulfide composite materials, in particular to a hypophosphite flame-retardant PPS composite material and a preparation method and application thereof. BACKGROUND

[0002] Polyphenylene sulfide (PPS) is widely used in aerospace, automotive functional parts and other fields due to its good mechanical properties, self-retardant properties, excellent fatigue properties and temperature resistance. However, polyphenylene sulfide material also has obvious shortcomings, such as the electrical tracking damage caused by applying high voltage to the surface of an insulator, the poor tracking resistance of polyphenylene sulfide, and the limitation of its application in high-voltage electrical systems.

[0003] The hypophosphite flame-retardant polyphenylene sulfide system has high flame-retardant efficiency, small addition amount and small influence on performance compared with other flame retardants. However, after adding the hypophosphite flame retardant to PPS, the hypophosphite will promote the formation of carbon conductive paths, further reducing the tracking resistance of PPS. At this time, other tracking resistance improvers have little effect on improving the tracking resistance of the system. In addition, in actual application, the product has low toughness and is prone to cracking during use, and the product has high risk in the field of vehicle-mounted products. For example, patent CN103827213 obtains a PPS resin composition with excellent tracking resistance, mechanical strength and low gas property by adding polyamide resin and metal hydroxide and dispersing them in an average particle size of 5 μm or less. However, a large amount of metal hydroxide leads to low toughness of the material. In product application, cracking is prone to occur.

[0004] Therefore, a hypophosphite flame-retardant PPS composition with high flame retardancy, high toughness and tracking resistance has broad application prospects. SUMMARY

[0005] Based on this, the purpose of the present application is to overcome the shortcomings of the prior art and provide a hypophosphite flame-retardant PPS composite material with good flame-retardant properties, high toughness and tracking resistance, and a preparation method and application thereof.

[0006] To achieve the above purpose, the technical scheme adopted by the present application is as follows: a hypophosphite flame-retardant PPS composite material, comprising the following components by weight: PPS resin 50-90 parts, glass fiber 10-50 parts, styrene-based thermoplastic elastomer 1-10 parts, hypophosphite flame retardant 4-8 parts, and phosphate 0.5-3 parts.

[0007] Preferably, the styrene thermoplastic elastomer comprises at least one of styrene thermoplastic elastomer SBS, styrene-ethylene-butylene-styrene block copolymer SEBS, styrene-ethylene-propylene-styrene block copolymer SEPS, and styrene-isobutylene-styrene triblock copolymer SIBS.

[0008] Preferably, the hypophosphite flame-retardant PPS composite material comprises the following components by weight: 3-6 parts of styrene thermoplastic elastomer, 4-6 parts of hypophosphite flame retardant, and 1-2 parts of phosphate.

[0009] Preferably, the mass percentage of styrene in the styrene thermoplastic elastomer is 20-70%, and more preferably, the mass percentage of styrene in the styrene thermoplastic elastomer is 35-45%. The mass percentage of styrene in the styrene thermoplastic elastomer is tested according to the standard test of ASTM D5775-2014.

[0010] Preferably, the weight percentage of the PPS resin in the hypophosphite flame-retardant PPS composite material is not less than 40%.

[0011] The present application prepares a hypophosphite flame-retardant PPS composite material with high flame retardancy, high toughness, and resistance to tracking by the synergy of PPS resin, styrene thermoplastic elastomer, hypophosphite flame retardant, and phosphate. On the one hand, the synergy of hypophosphite flame retardant and phosphate can improve the flame retardancy while reducing the amount of hypophosphite flame retardant. However, the PPS resin and hypophosphite can promote the formation of carbon to form a conductive path during the CTI test, resulting in failure of the tracking resistance test. However, the introduction of phosphate can destroy the original conductive path during the tracking resistance test, thereby significantly improving the tracking resistance. On the other hand, the styrene thermoplastic elastomer has weaker carbon formation than PPS, which can improve the tracking resistance. Meanwhile, the styrene thermoplastic elastomer, hypophosphite flame retardant, and phosphate can further improve the tracking resistance.

[0012] The inventors found in actual experiments that when the mass percentage of styrene in the styrene thermoplastic elastomer is 35-45%, the hypophosphite flame-retardant PPS composite material prepared therefrom has better tracking resistance and toughness while ensuring the flame retardancy.

[0013] Optionally, the PPS resin is in a weight part of one of 50, 51, 53, 55, 58, 60, 61, 63, 65, 68, 70, 72, 75, 80, 82, 85, 88, 90 or a range value of any two of them; the glass fiber is in one of 10, 12, 15, 18, 20, 21, 23, 25, 28, 30, 32, 35, 38, 40, 42, 45, 48, 50 or a range value of any two of them; the styrenic thermoplastic elastomer is in one of 1, 1.5, 2, 2.3, 2.5, 3, 3.5, 4, 4.5, 5, 6, 6.5, 7, 7.5, 8, 8.5, 9, 9.5, 10 or a range value of any two of them; the hypophosphite flame retardant is in one of 4, 4.5, 5, 6, 6.5, 7, 7.5, 8 or a range value of any two of them; the phosphate is in one of 0.5, 0.8, 1, 1.1, 1.3, 1.5, 2, 2.1, 2.3, 2.5, 3 or a range value of any two of them.

[0014] Preferably, the hypophosphite flame retardant comprises at least one of aluminum hypophosphite, calcium hypophosphite, magnesium hypophosphite.

[0015] Preferably, the phosphate comprises at least one of calcium phosphate, sodium phosphate, potassium phosphate, magnesium phosphate, aluminum phosphate, zinc phosphate, hydroxyapatite. Further preferably, the hydroxyapatite comprises at least one of iron hydroxyapatite, calcium hydroxyapatite, sodium hydroxyapatite, potassium hydroxyapatite.

[0016] Preferably, the hypophosphite flame-retardant PPS resin has a melt mass flow rate of ≥ 500 g / 10 min according to ISO 1133-2022 at a test temperature of 316 °C and a load of 5 kg. Further preferably, the PPS resin has a melt mass flow rate of 500-1800 g / 10 min according to ISO 1133-2022 at a test temperature of 316 °C and a load of 5 kg.

[0017] Optionally, the hypophosphite flame-retardant PPS resin has a melt mass flow rate of one or a range value of any two of 500 g / 10 min, 550 g / 10 min, 600 g / 10 min, 650 g / 10 min, 700 g / 10 min, 800 g / 10 min, 900 g / 10 min, 1000 g / 10 min, 1100 g / 10 min, 1200 g / 10 min, 1250 g / 10 min, 1300 g / 10 min, 1350 g / 10 min, 1400 g / 10 min, 1450 g / 10 min, 1500 g / 10 min, 1600 g / 10 min, 1700 g / 10 min, 1800 g / 10 min at a test temperature of 316 ℃ and a load of 5 kg according to ISO 1133-2022.

[0018] Preferably, the glass fiber is a chopped glass fiber, the diameter of the chopped glass fiber is 10-15 μm, the length is 3-6 mm, and the surface is treated with polyurethane. The glass fiber treated with polyurethane on the surface can improve the compatibility of the glass fiber and other components, improve the dispersibility of the glass fiber, and thus improve the dimensional stability of the product. Optionally, the diameter of the chopped glass fiber is measured by an optical microscope, and the length is measured by a vernier caliper.

[0019] Preferably, the hypophosphite flame-retardant PPS composite further comprises 0.1-3.5 parts of a processing aid, the processing aid being at least one of a lubricant, a colorant, and an antioxidant.

[0020] Optionally, the weight fraction of the antioxidant is 0.1-0.5 parts, and the antioxidant is at least one of a hindered phenol antioxidant and a phosphite antioxidant, such as antioxidant 168 (tris[2,4-di-tert-butylphenyl] phosphite), antioxidant 1010 (tetra[β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionic acid] pentaerythritol ester), and the like.

[0021] Optionally, the weight fraction of the lubricant is 0.1-1 part, and the lubricant is at least one of a stearate, a stearate ester, and an ethylene bis-stearamide, such as pentaerythritol stearate, zinc stearate, and the like.

[0022] Optionally, the weight fraction of the colorant is 0.1-2 parts, and the colorant is at least one of zinc sulfide, carbon black, iron red, titanium white powder, and iron yellow.

[0023] Further, the application provides a preparation method of the hypophosphite flame-retardant PPS composite material, comprising the following steps: uniformly mixing the components in proportion to obtain a mixture A; adding the mixture A into a main feeding port of a screw extruder, adding glass fibers into a side feeding port of the screw extruder, melt-extruding, granulating, and obtaining the hypophosphite flame-retardant PPS composite material.

[0024] Preferably, the temperature of the melt-extrusion is 220-320℃.

[0025] Further, the application provides application of the hypophosphite flame-retardant PPS composite material in automobile electronics, industrial equipment, household appliances. Alternatively, the application provides application of the hypophosphite flame-retardant PPS composite material in wafer boxes, turnover boxes, battery poles.

[0026] Compared with the prior art, the application has the following beneficial effects: the hypophosphite flame-retardant PPS composite material with high flame retardancy, high toughness and tracking resistance is prepared by the synergy of PPS resin, styrene-based thermoplastic elastomer, hypophosphite flame retardant and phosphate. On the one hand, the synergy of the hypophosphite flame retardant and the phosphate can improve the flame retardancy while reducing the amount of the hypophosphite flame retardant. Meanwhile, in the CTI test process, the hypophosphite promotes the formation of conductive paths, resulting in the failure of the tracking resistance test. However, the introduction of the phosphate can destroy the original conductive paths during the tracking resistance test, thereby significantly improving the tracking resistance. On the other hand, the styrene-based thermoplastic elastomer has weaker carbonization than PPS, which can improve the tracking resistance. Meanwhile, the synergy of the styrene-based thermoplastic elastomer, the hypophosphite flame retardant and the phosphate can further improve the tracking resistance. DETAILED DESCRIPTION

[0027] For better illustrating the purpose, technical scheme and advantages of the application, the application will be further described in combination with specific examples, which aims to understand the content of the application in detail, instead of limiting the application. All other examples obtained by the person skilled in the art without creative labor are within the protection scope of the application. The experimental reagents and instruments involved in the implementation of the application are common reagents and instruments, unless otherwise specified.

[0028] The raw materials used in the examples and comparative examples are described as follows, as shown in Table 1, but are not limited to these materials:

[0029] Table 1

[0030]

[0031] The glass fiber is fiberglass ECS309A-3-H, purchased from Chongqing International Composite Material, with a length of 3 mm, and a surface coated with 1 wt% polyurethane.

[0032] The antioxidant is a composite of commercially available hindered phenolic antioxidant 1010 and commercially available phosphite antioxidant 168 at a mass ratio of 1:1.

[0033] The lubricant is pentaerythritol stearate, commercially available.

[0034] Examples 1-14 and Comparative Examples 1-4

[0035] The hypophosphite flame-retardant PPS composite material according to the present application, the composition of the hypophosphite flame-retardant PPS composite material is shown in Tables 2-4. The preparation method of the hypophosphite flame-retardant PPS composite material comprises the following steps:

[0036] (1) Weigh each component according to the proportion;

[0037] (2) Mix the PPS resin, styrene-based thermoplastic elastomer, hypophosphite flame retardant, phosphate, antioxidant, and lubricant uniformly to obtain a mixture A;

[0038] (3) Add the mixture A to the main feeding port of the twin-screw extruder, and add the glass fiber to the side feeding port of the twin-screw extruder. The temperature of each section of the screw of the twin-screw extruder is 220-320°C. After melt extrusion and granulation, a hypophosphite flame-retardant PPS composite material is obtained.

[0039] Table 2

[0040]

[0041]

[0042] Table 3

[0043]

[0044] Table 4

[0045]

[0046]

[0047] Performance test

[0048] Vertical burning test: UL94-2018; the standard test piece with an injection molding specification of 125*13*0.8 mm is tested using a vertical burning tester; according to the standard, the test results include V-0, V-1, V-2, V-2, and the like.

[0049] Tracking resistance test: IEC 60112-2020, standard test piece of injection molding specification 100*100*3mm, tracking resistance tester is used for testing, unit: V.

[0050] Toughness: represented by bending deflection, test method is ISO 178-2010, electronic universal testing machine is used for testing, standard test piece of injection molding specification 80*10*4mm, test rate is 2mm / min, unit: mm.

[0051] The results of performance test are shown in Table 5.

[0052] Table 5

[0053]

[0054]

[0055] From the above table, it can be seen that the hypophosphite flame-retardant PPS composite material with high flame retardance, high toughness and tracking resistance is prepared by the synergy of PPS resin, styrene thermoplastic elastomer, hypophosphite flame retardant and phosphate.

[0056] From the comparison of example 1 and examples 3-7, it can be seen that when the mass percentage content of styrene in the styrene thermoplastic elastomer is 35-45%, the hypophosphite flame-retardant PPS composite material prepared therefrom has better tracking resistance and toughness under the premise of ensuring flame retardance.

[0057] From the comparison of example 1 and examples 11-14, it can be seen that when the styrene thermoplastic elastomer is 3-6 parts, the hypophosphite flame retardant is 4-6 parts, and the phosphate is 1-2 parts in the hypophosphite flame-retardant PPS composite material, the tracking resistance is better under the premise of ensuring flame retardance and toughness.

[0058] From the comparison of example 1 and comparative example 1, it can be seen that too much weight of phosphate in the hypophosphite flame-retardant PPS composite material has a great influence on toughness, and the toughness is less than 3mm, which cannot meet the demand.

[0059] From the comparison of example 1 and comparative example 2, it can be seen that when the styrene thermoplastic elastomer is not contained, the tracking resistance and toughness of the hypophosphite flame-retardant PPS composite material are poor, which cannot meet the demand.

[0060] From the comparison of example 1 and comparative example 3, it can be seen that after the phosphate is replaced by calcium borate, the toughness of the hypophosphite flame-retardant PPS composite material decreases, the tracking resistance is very poor, and the demand cannot be met.

[0061] From the comparison of Example 1 and Comparative Example 4, it can be seen that when no phosphate is contained, the hypophosphite flame-retardant PPS composite has poor tracking resistance and the flame-retardant performance is V-2, which cannot meet the requirement.

[0062] Finally, it should be noted that the above examples are only used to illustrate the technical solutions of the present application and not to limit the scope of protection of the present application. Although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present application can be modified or replaced by equivalents without departing from the essence and scope of the technical solutions of the present application.

Claims

1. A hypophosphite salt flame-retardant PPS composite, characterized in that, The components include the following weight parts: PPS resin 50-90 parts, glass fiber 10-50 parts, styrene-based thermoplastic elastomer 1-10 parts, hypophosphite flame retardant 4-8 parts, phosphate 0.5-3 parts; the phosphate includes at least one of calcium phosphate, sodium phosphate, potassium phosphate, magnesium phosphate, aluminum phosphate, zinc phosphate, hydroxyapatite.

2. The hypophosphite flame-retardant PPS composite of claim 1, wherein, The components include the following weight parts: styrene-based thermoplastic elastomer 3-6 parts, hypophosphite flame retardant 4-6 parts, phosphate 1-2 parts.

3. The hypophosphite flame-retardant PPS composite of claim 1, wherein, The styrene-based thermoplastic elastomer includes at least one of styrene-based thermoplastic elastomer SBS, styrene-ethylene-butylene-styrene block copolymer, styrene-ethylene-propylene-styrene block copolymer, styrene-isobutylene-styrene triblock copolymer.

4. The hypophosphite flame-retardant PPS composite of claim 1, wherein, The mass percentage content of styrene in the styrene-based thermoplastic elastomer is 20-70%.

5. The hypophosphite flame-retardant PPS composite of claim 4, wherein, The mass percentage content of styrene in the styrene-based thermoplastic elastomer is 35-45%.

6. The hypophosphite flame-retardant PPS composite of claim 1, wherein, The hypophosphite flame retardant includes at least one of aluminum hypophosphite, calcium hypophosphite, magnesium hypophosphite.

7. The hypophosphite flame-retardant PPS composite of claim 1, wherein, The hydroxyapatite includes at least one of ferric hydroxyapatite, calcium hydroxyapatite, sodium hydroxyapatite, potassium hydroxyapatite.

8. The hypophosphite flame-retardant PPS composite of claim 1, wherein, The PPS resin has a melt mass flow rate of ≥500g / 10min under the conditions of test temperature 316℃ and load 5kg according to ISO1133-2022.

9. The hypophosphite flame-retardant PPS composite of claim 1, wherein, The hypophosphite flame-retardant PPS composite material further includes 0.1-3.5 parts of a processing aid, which is at least one of a lubricant, a colorant, and an antioxidant.

10. A process for the preparation of a hypophosphite flame-retardant PPS composite according to any one of claims 1 to 9, characterized in that, The method includes the following steps: The components are mixed in proportion to obtain mixture A; mixture A is added to the main feeding port of the screw extruder, and the glass fiber is added to the side feeding port of the screw extruder, then melted and extruded, granulated to obtain the hypophosphite flame-retardant PPS composite material.

11. Use of the hypophosphite flame-retardant PPS composite material according to any one of claims 1-9 in automotive electronics, industrial equipment, and household appliances.

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