Antimony-free flame-retardant nylon material with high glowing filament temperature as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of high polymer materials, and particularly relates to an antimony-free flame-retardant nylon material with high glowing filament temperature as well as a preparation method and application of the antimony-free flame-retardant nylon material. The invention relates to an antimony-free flame-retardant nylon material with high glowing filament temperature. The antimony-free flame-retardant nylon material is prepared from the following raw materials in percentage by weight: 70-74% of nylon 6 (PA6) resin, 16.5-18.5% of brominated flame retardant, 6-12% of phosphorus flame retardant, 0.5-1.5% of auxiliaries and 0.5-1% of black masterbatch. According to the invention, antimony trioxide is replaced by the phosphorus-based flame retardant, the phosphorus-based flame retardant and bromine are subjected to synergistic flame retardance, the flame retardance reaches UL94V0 (1.6 mm), a high glowing filament temperature GWIT850 DEG C can be obtained, and a glue opening of a black workpiece is not whitened.

Description

Technical Field

[0001] The present invention belongs to the technical field of polymer materials, and particularly relates to an antimony-free high glow wire temperature flame-retardant nylon material, a preparation method thereof, and an application thereof. Background Art

[0002] Nylon PA resin is widely used in the fields of household appliances, electronic and electrical appliances, industrial power engineering, high-speed rail, and the automotive industry. Flame-retardant nylon is mostly used in industrial power engineering, household appliances, and electronic and electrical appliances to prepare plastic parts, including various coils of motors, compressor covers of air conditioners, and electrical switches. Flame-retardant nylon materials have become high-quality materials in many fields due to their excellent flame-retardant properties, outstanding mechanical and mechanical properties, excellent electrical insulation properties, good heat stability, product R & D flexibility, and cost controllability.

[0003] The technology of reinforced flame-retardant nylon, including glass fiber and carbon fiber reinforced flame-retardant nylon, is mature. Whether it is halogen-free or halogen-containing flame retardant, there are suitable flame retardants to meet the requirements of 1.6mm V0. On the other hand, for non-reinforced flame-retardant nylon, most of it is MCA flame-retardant nylon, but there is dripping, and it can also reach V0. There are also halogen-free flame-retardant nylons such as MPP, organic hypophosphite, aluminum diethyl phosphinate, and ammonium polyphosphate. The national invention patent [CN201711306022.0] provides a low-cost and high-performance halogen-free flame-retardant nylon material, which uses MPP and inorganic powder for compounding to obtain a non-reinforced flame-retardant V0 nylon material. The national invention patent [CN201510674124.2] provides a non-reinforced halogen-free flame-retardant nylon with a small amount of flame retardant added by compounding MCA and MP. In addition, for non-reinforced flame-retardant nylon related to the glow wire, the national invention patent [CN201310236197.4] uses a variety of halogen-free flame retardants for compounding, including MPP, ammonium polyphosphate, red phosphorus, MCA, hypophosphite, melamine, silicone, charring agent, and glow wire ignition temperature enhancer to provide a high glow wire ignition temperature flame-retardant nylon material. The national invention patent [CN201711192202.0] also provides a non-reinforced flame-retardant nylon with a GWIT of 825 degrees, which is also organic hypophosphite, ammonium polyphosphate, and MCA, zinc borate, montmorillonite, talc powder, and barium sulfate. The national invention patent [CN201510355943.0] uses MC-25 and TPP to provide a flame-retardant nylon with a GWIT of 850 °C. The national invention patent [CN201810004004.5] also uses MCA to prepare a flame-retardant PA6 material with a high glow wire ignition temperature.

[0004] In the above-mentioned patent, for the non-reinforced halogen-free flame-retardant nylon using zinc borate, MCA, and MPP, the gate will turn white in black products. Especially now that manufacturers use fully automatic injection molding, the gate is narrow or a dot gate, and it is inevitable that the gate turns white because the compatibility of zinc borate, MCA, and MPP with nylon is poor. The author's experiment shows that the Clariant organic hypophosphite flame retardant alone or in combination with MCA does not cause the gate to turn white, but the glow wire ignition temperature of the two is lower than 700 °C.

[0005] Since the halogen-free flame-retardant nylon cannot solve the problem of gate whitening and high glow wire ignition temperature, we turn to brominated flame-retardant nylon. The national invention patent [CN108250741 A] also uses zinc borate instead of antimony trioxide to resist corrosion and improve CTI. There is a sentence in the article stating that brominated antimony flame retardants are prone to generate gas such as antimony tribromide during processing and injection molding. Thus, it can be seen that gas generated by brominated antimony ignites at a high glow wire temperature. Then, for flame-retardant nylon with a high GWIT, antimony must be replaced. If zinc borate can completely replace antimony for flame retardancy, it is okay, but the gate of the molded part turns white. The national invention patent [CN102796367 A] uses alumina to replace 50-70% of antimony in reinforced flame-retardant nylon, and the national invention patent [CN101845153 A] uses 50% of the LHX-999 inorganic flame retardant to replace antimony in reinforced flame-retardant nylon. In non-reinforced flame-retardant nylon, the addition amount of the flame retardant is more, and it is more difficult to achieve flame retardancy. This requires the synergist to cooperate efficiently with bromine. Otherwise, the addition amount is large, and it is difficult to meet the requirement of V0 for 1.6 mm thickness. Through continuous screening of antimony substitutes and optimizing the flame retardant formula, this patent has found a phosphorus-based flame retardant that can replace 100% of antimony and cooperate efficiently with bromine. The price is only one-fourth of that of antimony, and a flame-retardant nylon with a high glow wire temperature is prepared. Moreover, the phosphorus-based flame retardant is an organic material and can be compatible with nylon. When the injection pressure of the molded part is high, the phosphorus-based flame retardant will not precipitate, and it also greatly improves the material fluidity. From previous research, it is known that the addition of antimony will generate gas of antimony tribromide, reducing the glow wire temperature of the material. Antimony-based flame retardants are expensive and have poor availability, while the antimony-free flame-retardant nylon of this patent has an intrinsically high glow wire ignition temperature. Summary of the Invention

[0006] To solve the deficiencies of the prior art, the present invention provides an antimony-free flame-retardant nylon material with a high glow wire temperature, its preparation method, and applications. The nylon (PA6) material provided by the present invention has a low cost, can overcome the problem of gate whitening of the existing materials in black products, and meets the requirement of a high glow wire GWIT of 850 °C.

[0007] The technical solutions provided by the present invention are as follows:

[0008] The invention discloses an antimony-free high glow-wire temperature flame-retardant nylon material, which is composed of the following raw materials in percentage by weight: 70-74% nylon 6 (PA6) resin, 16.5-18.5% bromine flame retardant, 6-12% phosphorus flame retardant, 0.5-1.5% auxiliary agent and 0.5-1% black masterbatch.

[0009] The above technical solution replaces antimony trioxide with a phosphorus-based flame retardant, and synergizes with bromine to achieve flame retardancy of UL94V0 (1.6mm) and a high glow wire temperature GWIT850°C, and the glue mouth of the black part does not turn white.

[0010] Preferably, the content of nylon 6 resin is 74%.

[0011] Preferably, the content of the black masterbatch is 1%.

[0012] Specifically: the brominated flame retardant is selected from any one or more of polybrominated styrene, brominated polystyrene or decabromodiphenylethane.

[0013] Polybrominated styrene is commercially available, for example, as product model PBS-64HW from Great Lakes Corporation of the United States.

[0014] Brominated polystyrene is commercially available, for example, as the product XZ-6700 from Shandong Brother Chemical.

[0015] Specifically: the phosphorus-based flame retardant is polyphosphate.

[0016] Preferably, the weight percentage of phosphorus in the polyphosphate is ≥ 42%.

[0017] Polyphosphates are commercially available, for example, under the brand name XL-T100A from Shandong Haiwang Chemical Co., Ltd.

[0018] The antimony-free high glow-wire temperature flame-retardant PA6 material provided by the above technical solution is based on a flame retardant obtained by mixing a main flame retardant and a phosphorus-based flame retardant, wherein the phosphorus flame retardant not only has a high efficiency synergistic effect with the bromine flame retardant, but also 100% replaces the bromine antimony flame retardant, completely avoiding the fire of the high glow-wire temperature material caused by the antimony component, and also reducing the cost.

[0019] Specifically: the auxiliary agent includes a fluidity improver and / or a demoulding lubricant.

[0020] Specifically, the fluidity improver is selected from any one of polyester oligomers, dendritic resins or hyperbranched resins or a mixture of two thereof, and preferably, is a carboxyl-terminated hyperbranched polymer.

[0021] Polyester oligomers are commercially available, for example, as product CBT-100 from Cyclics.

[0022] Dendritic resins are commercially available, such as the CYD-C600 model product from Chenyuan Company in Weihai, Shandong.

[0023] Carboxyl-terminated hyperbranched polymers are commercially available, such as Hyper C181 from Hyperbranched in Wuhan.

[0024] Specifically, the demolding lubricant is selected from any one or a mixture of two of TAF lubricant, silicone masterbatch or E-wax. Preferably, it is a silicone masterbatch.

[0025] TAF lubricant is commercially available, such as the TAF-A model product from Xingtai Guoguang Company in Suzhou.

[0026] Silicone masterbatch is commercially available, such as the LYSI-406 model product from Silike Company in Chengdu.

[0027] E-wax is commercially available, such as the Licowax model product from Clariant.

[0028] Specifically: The nylon 6 resin is any one or a mixture of two of medium-viscosity nylon or low-viscosity nylon available on the market.

[0029] Specifically: The masterbatch is carrier-free blue-phase carbon black sand, which is commercially available, such as 05C black sand from Shencai in Dongguan.

[0030] The present invention also provides a method for preparing an antimony-free high glow wire temperature flame-retardant nylon material, comprising the following steps:

[0031] 1) Pulverize and mix the brominated flame retardant, the phosphorus-based flame retardant and the auxiliary agent, and then add them to a high-speed mixer for mixing to obtain a mixed flame retardant;

[0032] 2) Then add the mixed flame retardant, the nylon 6 resin and the masterbatch together to a high-speed mixer for mixing, and melt-extrude to obtain the product.

[0033] The present invention also provides the application of the antimony-free high glow wire temperature flame-retardant nylon material as an electronic material, an electrical material or a household electrical appliance material.

[0034] The high glow wire flame-retardant PA6 material provided by the present invention meets the requirements of the 850 °C glow wire unattended electrical appliances in the EU IEC60695 standard and can be used as an electronic and electrical or household electrical appliance material.

[0035] Preferably: As the material for the wiring case of a refrigerator compressor.

[0036] The high glow wire flame-retardant PA6 material provided by the present invention is particularly suitable as the material for the wiring case of a refrigerator compressor because it has a flame retardancy of V0, a glow wire GWIT above 850 °C, resistance to refrigerant, and a CTI value passing 175V.

[0037] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0038] 1) The organophosphorus flame retardant used has a high synergistic effect with bromine, replacing the antimony flame retardant by 100%. This avoids the formation of antimony tribromide gas by the antimony component, which can cause a fire and reduce the glow wire temperature. In addition, its price is only one-fourth of that of antimony, making it highly cost-effective.

[0039] 2) The gate of the flame-retardant nylon black parts does not turn white.

[0040] 3) Obtain flame-retardant nylon with a GWIT of 850°C.

[0041] 4) It is possible to avoid using antimony-based flame retardants. Specific Embodiments

[0042] The principles and features of the present invention will be described below. The examples given are only used to explain the present invention and are not intended to limit the scope of the present invention.

[0043] Unless otherwise specified, the test methods used in the examples are all conventional methods; the materials, reagents, etc. used, unless otherwise specified, are reagents and materials that can be obtained commercially.

[0044] The materials are as follows: PA6 resin is YH800 or YH400 from Hunan Yuehua Company; decabromodiphenylethane from Shandong Haiwang; brominated polystyrene from Shandong Xiongdi Chemical Industry; ordinary grade antimony trioxide from Hunan Chenzhou with a purity of 99.8%; the phosphorus-based flame retardant is XL-T100A from Shandong Haiwang; the flow modifier is Hyper C181 from Wuhan Hyperbranched; the black masterbatch is 05C black sand from Dongguan Shencai.

[0045] Prepare each antimony-free high glow wire temperature flame-retardant nylon material according to the following steps:

[0046] 1) Powder and mix the bromine-based flame retardant, phosphorus-based flame retardant and additives, and then add them to a high-speed mixer to mix evenly to obtain a uniformly mixed flame retardant.

[0047] 2) Then add the uniformly mixed flame retardant, nylon 6 resin and black masterbatch together to a high-speed mixer to mix evenly, and melt and extrude to obtain the product. The extrusion temperature during melt extrusion in a twin-screw extruder is about 225°C and the screw speed is 360 revolutions per minute.

[0048] The raw materials used in each example and comparative example (by weight percentage) are specifically shown in the following table:

[0049] Component Comparative Example 1 Comparative Example 2 Comparative Example 3 Example 1 Example 2 Example 3 YH800 70 70 70 70 74 74 Decabromodiphenylethane 16.5 15 13 16.5 16.5 18.5 Antimony Trioxide 0 1.5 1.5 0 0 0 LHX-999 12 12 14 0 0 0 XL-T100A 0 0 0 12 8 6 C181 0.5 0.5 0.5 0.5 0.5 0.5 Black Sand 1 1 1 1 1 1

[0050] Performance Test

[0051] The flame retardancy, Izod notched impact strength, tensile strength, melt index, and glow wire temperature of the flame-retardant PA6 materials in the examples and comparative examples were tested using the corresponding standards, and the results are shown in the following table:

[0052]

[0053]

[0054] From the test data of Example 1 and Example 3, it can be seen that both the flame retardancy and the glow wire temperature meet the standards. However, for Comparative Examples 1-3, the two properties of flame retardancy and glow wire temperature cannot be taken into account simultaneously. It can also be concluded from this that the synergistic flame retardancy of the phosphorus-based flame retardant and the bromine-based flame retardant is efficient, and the phosphorus-based flame retardant can replace expensive antimony trioxide by 100%. The phosphorus-based flame retardant can also improve the fluidity and impact strength of the material and reduce the density, which are all the advantages of this flame retardant.

[0055] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. An antimony-free high glow-wire temperature flame-retardant nylon material, characterized in that: The invention is composed of the following raw materials in percentage by weight: 70-74% nylon 6 resin, 16.5-18.5% bromine flame retardant, 6-12% phosphorus flame retardant, 0.5-1.5% auxiliary agent and 0.5-1% black masterbatch.

2. The antimony-free high glow-wire temperature flame-retardant nylon material according to claim 1, characterized in that: The brominated flame retardant is selected from any one or more of polybrominated styrene, brominated polystyrene or decabromodiphenylethane.

3. The antimony-free high glow-wire temperature flame-retardant nylon material according to claim 1, characterized in that: The phosphorus-based flame retardant is polyphosphate.

4. The antimony-free high glow-wire temperature flame-retardant nylon material according to claim 3, characterized in that: The weight percentage of phosphorus in the polyphosphate is ≥42%.

5. The antimony-free high glow-wire temperature flame-retardant nylon material according to claim 1, characterized in that: The auxiliary agent includes a fluidity improver and / or a mold release lubricant.

6. The antimony-free high glow-wire temperature flame-retardant nylon material according to claim 5, characterized in that: The fluidity improver is selected from any one or a mixture of two of polyester oligomers, dendritic resins or hyperbranched resins; The demoulding lubricant is selected from any one of TAF lubricant, silicone masterbatch or E wax or a mixture of two thereof.

7. The antimony-free high glow-wire temperature flame-retardant nylon material according to claim 1, characterized in that: The nylon 6 resin is any one of commercially available medium-viscosity nylon or low-viscosity nylon, or a mixture of the two.

8. A method for preparing the antimony-free high glow-wire temperature flame-retardant nylon material according to any one of claims 1 to 7, characterized in that: The following steps are involved: 1) Powdering the brominated flame retardant, the phosphorus flame retardant and the auxiliary agent and mixing them uniformly, and then adding them into a high-speed mixer and mixing them uniformly to obtain a uniformly mixed flame retardant; 2) Add the flame retardant, nylon 6 resin and black masterbatch into a high-speed mixer, mix well, and melt-extrude to obtain the product.

9. An application of the antimony-free high glow-wire temperature flame-retardant nylon material according to any one of claims 1 to 7, characterized in that: As electronic or electrical materials; Or, as a material for home appliances.

10. The use of the antimony-free high glow-wire temperature flame-retardant nylon material according to claim 9, characterized in that: Used as wiring shell material for refrigerator compressors.

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