Fluorine-free halogen-free flame-retardant polypropylene composition as well as preparation method and application thereof
By adding a specific amount of second polypropylene resin and compounded flame retardant to polypropylene resin, and adding active additives, the deficiencies of fluorine-free and halogen-free flame-retardant polypropylene compositions in terms of flame retardancy and mechanical properties are solved, and the processing performance is improved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- KINGFA SCI & TECH CO LTD
- Filing Date
- 2026-02-27
- Publication Date
- 2026-05-12
AI Technical Summary
Existing fluorine-free and halogen-free flame-retardant polypropylene compositions cannot simultaneously possess good flame-retardant properties and mechanical properties, and also have poor processing performance.
A fluorine-free and halogen-free flame-retardant polypropylene composition was prepared by adding a specific amount of a second polypropylene resin and a compounded flame retardant to a polypropylene resin, and by adding active additives. The second polypropylene resin was used to improve molecular chain entanglement and melt elasticity, and the compounded flame retardant was combined to improve flame retardancy and mechanical properties.
This study achieved the improvement of mechanical and processing properties of fluorine-free and halogen-free flame-retardant polypropylene compositions while maintaining good flame retardancy.
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Abstract
Description
Technical Field
[0001] This invention relates to the field of polymer materials technology, and more specifically, to a fluorine-free and halogen-free flame-retardant polypropylene composition, its preparation method, and its application. Background Technology
[0002] Polypropylene resin has good impact resistance and corrosion resistance, and is widely used in electronic appliances, automotive materials, office supplies, and other materials. However, polypropylene resin is flammable and degrades very easily at high temperatures. During combustion, it is prone to dripping and carrying flames. Fluorine-containing anti-dripping agents are usually added to solve the problem of flame retardant dripping. The REACH ban aims to prohibit the manufacture, placement on the market, and use of all perfluoroalkyl and polyfluoroalkyl compounds (PFAS) in the European Union.
[0003] Nitrogen-phosphorus flame retardants are highly efficient and environmentally friendly, making them an effective solution for halogen-free flame retardancy. To achieve V-0 flame retardancy without the addition of anti-dripping agents, the flame retardant content generally needs to be appropriately increased. However, using more than 30% flame retardant in polypropylene resin can significantly deteriorate the mechanical and processing properties of the system. Existing technology CN117730121A discloses a fluorine-free and halogen-free flame-retardant polypropylene, which uses high melt strength polypropylene (HMS) with a melt strength of at least 20 cN. PP was used as an anti-dripping agent, with high melt strength PP added at a level of over 10%, achieving V-0 flame retardancy in 1.6mm specimens and exhibiting similar mechanical properties to samples with added anti-dripping agents. However, due to the high melt strength content, the system had a low melt index and poor processing performance. Summary of the Invention
[0004] The purpose of this invention is to overcome the shortcomings of the prior art in which fluorine-free and halogen-free flame-retardant polypropylene compositions cannot simultaneously possess good flame-retardant properties and mechanical properties, and to provide a fluorine-free and halogen-free flame-retardant polypropylene composition.
[0005] Another object of the present invention is to provide a method for preparing the above-mentioned fluorine-free and halogen-free flame-retardant polypropylene composition.
[0006] Another object of the present invention is to provide applications of the above-described polypropylene combination.
[0007] To achieve the above objectives, the present invention adopts the following technical solution:
[0008] A fluorine-free and halogen-free flame-retardant polypropylene composition comprising the following components in parts by weight: 56-70 parts of the first polypropylene resin; 6-12 parts of the second polypropylene resin; 24-28 parts of compound flame retardant; 0.2 to 2 parts of active additives; Wherein, the second polypropylene resin has a loss angle tangent tgδ≤2 at 180℃ and a frequency of 0.1Hz; the compound flame retardant includes piperazine flame retardants, melamine salt flame retardants and phosphine / phosphate flame retardants.
[0009] This invention provides a fluorine-free and halogen-free flame-retardant polypropylene composition. By adding a small amount of a second polypropylene resin and active additives, and by compounding with different types of flame retardants, the molecular chain entanglement in the polypropylene composition can be effectively increased, the melt elasticity can be improved, and the molecular chain slippage at high temperatures can be delayed. This results in a polypropylene composition with good flame retardancy and mechanical properties, as well as good processing performance.
[0010] It should be noted that the fluorine-free and halogen-free flame-retardant polypropylene composition described in this invention refers to a composition from flame-retardant additives where the fluorine content does not exceed 10 ppm, the total chlorine and bromine content does not exceed 1500 ppm, and the individual chlorine and bromine content does not exceed 900 ppm, achieving a flame retardancy of 1.5 mmV-0.
[0011] It should be noted that, in the fluorine-free and halogen-free flame-retardant polypropylene composition described in this invention, the content of the first polypropylene resin is preferably not less than 60 wt%.
[0012] It should be noted that the active ingredient is 0.2 to 2 parts, for example, but not limited to 0.2 parts, 0.3 parts, 0.4 parts, 0.5 parts, 0.6 parts, 0.7 parts, 0.8 parts, 0.9 parts, 1 part, 1.1 parts, 1.2 parts, 1.3 parts, 1.4 parts, 1.5 parts, 1.6 parts, 1.7 parts, 1.8 parts, 1.9 parts, or 2 parts, etc., and the specific values between the above values are not exhaustively listed in this invention due to space limitations and for the sake of brevity.
[0013] Preferably, the active additive includes an acrylic metal salt.
[0014] More preferably, the active additive includes one or more of zinc acrylate, zinc methacrylate, or aluminum acrylate.
[0015] It should be noted that the second polypropylene resin is 6 to 12 parts, for example, but not limited to 6 parts, 6.5 parts, 7 parts, 7.5 parts, 8 parts, 8.5 parts, 9 parts, 9.5 parts, 10 parts, 10.5 parts, 11 parts, 11.5 parts, or 12 parts, etc., and the specific values between the above values are not exhaustively listed in this invention due to space limitations and for the sake of brevity.
[0016] It should be noted that the tangent value tgδ of the loss angle δ of the second polypropylene resin of the present invention at 180°C and 0.1Hz is ≤2, for example, but not limited to ≤2, 1.9, 1.8, 1.7, 1.6, 1.5, 1.4, 1.3, 1.2, 1.1, 1, 0.9, 0.8 or 0.7, etc., as well as specific values between the above values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values included in the range.
[0017] Preferably, the tangent of the loss angle δ of the second polypropylene resin at 180°C and a frequency of 0.1 Hz is 0.8~1.8.
[0018] More preferably, the tangent of the loss angle δ of the second polypropylene resin at 180°C and a frequency of 0.1 Hz is 1.0~1.6.
[0019] Specifically, the tangent tgδ of the loss angle δ of the second polypropylene resin at 180°C and 0.1Hz was measured by a rotational rheometer. The test temperature was 180°C, the strain was 1%, and a frequency scan was performed. The frequency scan range was 0.1~100rad / s.
[0020] Preferably, in the fluorine-free and halogen-free flame-retardant polypropylene composition, the content of the second polypropylene resin is 5-15 wt%.
[0021] More preferably, in the fluorine-free and halogen-free flame-retardant polypropylene composition, the content of the second polypropylene resin is 7-13 wt%.
[0022] The second polypropylene resin of this invention can be either homemade or commercially available.
[0023] Preferably, the second polypropylene resin can be prepared by the following method: The PP powder, crosslinking agent, initiator and free radical stabilizer are mixed evenly and then extruded through a twin-screw extruder to obtain the final product.
[0024] Specifically, the melt flow rate of the PP powder at 230℃ and 2.16kg load is 2.5~3.5g / 10min.
[0025] Specifically, the crosslinking agent includes one or more of triallyl isocyanurate, 1,3,5-triglycidyl-S-triazine trione, pentaerythritol triacrylate, trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, or glycerol trihydroxypropyl ether triacrylate.
[0026] Specifically, the initiator includes benzoyl peroxide, dicumyl peroxide, lauroyl peroxide, and 2,5-dibenzoyl peroxide. dimethyl (2,5) One or more of di-tert-butyl peroxyhexane or tert-butyl peroxide.
[0027] Specifically, the free radical stabilizer includes zinc dimethyl thiocarbamate and / or zinc dibutyl thiocarbamate.
[0028] Specifically, the mass ratio of the PP powder, crosslinking agent, initiator and free radical stabilizer is 100:(1~4):(0.02~0.08):(0.15~0.25).
[0029] Specifically, the tangent value tgδ of the loss angle δ at 180℃ and 0.1Hz refers to the tangent value of the loss angle δ. The larger the tgδ value, the less the melt's recovery can keep up with the stress change.
[0030] Specifically, the loss angle tangent tgδ of the second polypropylene resin at 180°C and 0.1Hz can be adjusted by controlling the amount of crosslinking agent added. The less crosslinking agent added, the larger the loss angle tangent tgδ of the second polypropylene resin at 180°C and 0.1Hz.
[0031] Specifically, the tangent value tgδ of the loss angle δ of the second polypropylene resin at 180°C and 0.1Hz can also be adjusted by adjusting the temperature of the twin-screw extruder. The higher the temperature of the twin-screw extruder, the higher the corresponding tangent value tgδ of the loss angle δ at 180°C and 0.1Hz.
[0032] Specifically, the temperature of the twin-screw extruder is 140~160℃ in zone one, 150~170℃ in zone two, 160~180℃ in zone three, 170~190℃ in zones four to eight, 160~180℃ in zone nine, and 150~170℃ in zone ten.
[0033] Specifically, the feeding speed of the twin-screw extruder is 20~30 rpm.
[0034] Specifically, the screw speed of the twin-screw extruder is 250~350 rpm.
[0035] It should be noted that the compound flame retardant is 24 to 28 parts, for example, but not limited to 24 parts, 24.5 parts, 25 parts, 25.5 parts, 26 parts, 26.5 parts, 27 parts, 27.5 parts, or 28 parts, etc., and the specific values between the above values are not exhaustively listed in this invention due to space limitations and for the sake of brevity.
[0036] Preferably, in the fluorine-free and halogen-free flame-retardant polypropylene composition of the present invention, the content of the compounded flame retardant is 20~28wt%.
[0037] Preferably, the piperazine flame retardant includes one or more of piperazine phosphate, piperazine pyrophosphate, or piperazine polyphosphate.
[0038] Preferably, the melamine salt flame retardant includes melamine pyrophosphate flame retardant and / or melamine polyphosphate flame retardant.
[0039] Preferably, the phosphine / phosphate flame retardant includes one or more of aluminum hypophosphite, calcium hypophosphite, or aluminum diethylphosphite.
[0040] Preferably, the melt flow rate of the polypropylene resin at 230°C and 2.16 kg load is ≥28 g / 10 min.
[0041] More preferably, the melt flow rate of the polypropylene resin at 230°C and 2.16 kg load is 30~70 g / 10 min.
[0042] Specifically, the test standard for the melt flow rate is GB / T 3682.1-2018.
[0043] Preferably, the polypropylene resin comprises homopolymer polypropylene and / or copolymer polypropylene.
[0044] Without affecting the flame retardant and mechanical properties of the fluorine-free and halogen-free flame retardant polypropylene composition of the present invention, the fluorine-free and halogen-free flame retardant polypropylene composition further includes 0.5 to 2 parts of processing aids.
[0045] Specifically, the processing aids include, but are not limited to, one or more of antioxidants, lubricants, or colorants.
[0046] The antioxidants described in this invention can be commonly used antioxidants, such as, but not limited to, hindered phenolic antioxidants and / or phosphite antioxidants.
[0047] Specifically, the hindered phenolic antioxidant is one or more of N,N'-hexamethylene bis(3,5-di-tert-butyl-4-hydroxyphenylpropionamide) (Irganox 1098), pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] (Irganox 1010), 1,6-hexanediol bis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] (Irganox 259), octadecyl β-(4-hydroxy-3,5-di-tert-butylphenyl)propionate (Irganox 1076), or 3,9-bis{2-[3-(3-tert-butyl-4-hydroxy-5-methylphenyl)acrylic acid]-1,1-dimethyl}-2,4,8,10-tetraoxaspirocycloundecane (ADK AO-80).
[0048] The phosphite antioxidant is one or more of tris(2,4-di-tert-butylphenyl) phosphite (Irganox 168), bis(2,6-di-tert-butyl-4-tolyl) pentaerythritol phosphite (PEP-36), or 627A.
[0049] The lubricant described in this invention can be a commonly used lubricant, such as, but not limited to, one or more of zinc stearate, calcium stearate, ester lubricants, or amide lubricants.
[0050] The color powder described in this invention can be selected from, for example but not limited to, carbon black, zinc sulfide, and other organic and inorganic color powders used for dyeing.
[0051] The present invention also provides a method for preparing the above-mentioned fluorine-free and halogen-free flame-retardant polypropylene composition, comprising the following steps: The components are mixed evenly in proportion, and then melt-extruded and granulated to obtain a fluorine-free and halogen-free flame-retardant polypropylene composition.
[0052] Specifically, the melt extrusion is performed using a screw extruder.
[0053] Specifically, the temperature of the first zone of the screw extruder is 110~130℃, and the temperature of the second to tenth zones is 160~180℃; the screw speed of the screw extruder is 200~300rpm; and the length-to-diameter ratio of the screw of the screw extruder is (38~42):1.
[0054] This invention also protects the use of the above-mentioned fluorine-free and halogen-free flame-retardant polypropylene composition in the preparation of housing materials for household appliances, especially suitable for components requiring good flame retardancy and impact resistance.
[0055] A component is made from the above-mentioned fluorine-free and halogen-free flame-retardant polypropylene composition, such as the back cover of a television or monitor, a power supply box, a charger housing, an electric kettle, a coffee maker, a rice cooker, a microwave oven, etc.
[0056] Compared with the prior art, the beneficial effects of the present invention are: This invention provides a fluorine-free and halogen-free flame-retardant polypropylene composition. A small amount of a specific second polypropylene resin is added to polypropylene resin, along with a compounded flame retardant and active additives. The resulting fluorine-free and halogen-free flame-retardant polypropylene composition has good flame retardancy, as well as good mechanical and processing properties. Detailed Implementation
[0057] The technical solutions in the embodiments of the present invention will be clearly and completely described below, but the implementation of the present invention is not limited thereto.
[0058] Unless otherwise specified, the reagents, methods and equipment used in this invention are all conventional reagents, methods and equipment in this technical field.
[0059] 1. The raw materials used in the following examples and comparative examples are as follows: First polypropylene resin: The first polypropylene resin 1: PP 7935E1, with a melt flow rate of 60 g / 10 min at 230°C and a load of 2.16 kg, was purchased from ExxonMobil. First polypropylene resin 2: PP 8285E, with a melt flow rate of 30 g / 10 min at 230°C and 2.16 kg load, purchased from ExxonMobil; Second polypropylene resin: The second polypropylene resin 1: MFX8, with a loss angle tangent tgδ of 1.5 at 180°C and a frequency of 0.1Hz, was purchased from Nippon Polypropylene Co., Ltd. Second polypropylene resin 2: The tangent of the loss angle δ, tgδ, is 1.4 at 180℃ and 0.1Hz; it is self-made. Second polypropylene resin 3: The tangent of the loss angle δ, tgδ, is 1.7 at 180℃ and 0.1Hz; it is self-made. Second polypropylene resin 4: The tangent of the loss angle δ, tgδ, is 1.8 at 180℃ and 0.1Hz; it is self-made. Second polypropylene resin 5: The tangent of the loss angle δ, tgδ, is 2.2 at 180℃ and 0.1Hz; it is self-made. The second polypropylene resin 2-5 is prepared by the following method: 100 parts by weight of PP powder (T30S powder, melt flow rate of 3 g / 10 min at 230℃ and 2.16 kg load, purchased from Ningbo Jinfeng), 2 parts by weight, 1.8 parts by weight, 1.5 parts by weight, and 1.2 parts by weight of triallyl isocyanurate, 0.05 parts by weight of benzoyl peroxide, and 0.2 parts by weight of zinc dimethyl dithiocarbamate were mixed evenly and fed into a twin-screw extruder for extrusion to obtain second polypropylene resins 2, 3, 4, and 5, respectively; the temperature of the first zone of the twin-screw extruder was 120℃, and the temperature of the second zone was 170℃. The temperature in zone three is 180℃, the temperature in zones four to eight is 170℃, the temperature in zone nine is 170℃, and the temperature in zone ten is 160℃. The feeding speed of the twin-screw extruder is 25 rpm, the length-to-diameter ratio of the twin-screw extruder is 40:1, and the screw speed is 250 rpm. The loss tangent tgδ of the second polypropylene resin at 0.1 Hz and 180℃ is changed by adjusting the amount of triallyl isocyanurate. The smaller the amount of triallyl isocyanurate, the larger the loss tangent tgδ of the second polypropylene resin at 0.1 Hz and 180℃.
[0060] Active additives: Active additive 1: Zinc methacrylate, ZDMA, purchased from Shaoguan Yang'an Chemical Co., Ltd.; Active additive 2: Zinc acrylate, ZA, purchased from Shaoguan Yang'an Chemical Co., Ltd.; Piperazine flame retardant: piperazine pyrophosphate, P190, purchased from Hunan Meilaipo Technology Development Co., Ltd.; Melamine flame retardant: melamine polyphosphate, MPP, purchased from Zhenjiang Xingxing Flame Retardant Co., Ltd.; Phosphine / phosphate flame retardant: aluminum diethylphosphinate, BEP-22E, purchased from Zhuhai Wantong; Compound flame retardant 1: A compound of piperazine flame retardant, melamine flame retardant and phosphine / phosphate flame retardant in a mass ratio of 1.5:1:0.3; Compound flame retardant 2: A compound of piperazine flame retardant, melamine flame retardant and phosphine / phosphate flame retardant in a mass ratio of 2:1:0.6; Compound flame retardant 3: A compound of melamine flame retardant and phosphine / phosphate flame retardant in a mass ratio of 1:0.3; Compound flame retardant 4: A compound of piperazine flame retardant and phosphine / phosphate flame retardant in a mass ratio of 1.5:0.3; Compound flame retardant 5: A compound of piperazine flame retardant and melamine flame retardant in a mass ratio of 2:1; Processing aids: Antioxidants: A compound of antioxidant 1010 and antioxidant 168 in a 1:1 mass ratio, both of which are commercially available; Lubricant: Calcium stearate, commercially available; It should be noted that the same raw materials were used in the parallel experiments of each embodiment and comparative example.
[0061] 2. The fluorine-free and halogen-free flame-retardant polypropylene compositions described in the embodiments and comparative examples were prepared according to the formulations in Tables 1-2 by the following preparation methods: The components are mixed evenly in proportion and added to a screw extruder for melt extrusion and granulation to obtain a fluorine-free and halogen-free flame-retardant polypropylene composition. The temperature of the first zone of the screw extruder is 120°C, and the temperature of the second to tenth zones is 210°C. The screw speed of the screw extruder is 450 rpm, and the length-to-diameter ratio of the screw extruder is 40:1.
[0062] 3. Performance Testing (1) Flame retardant performance test: The polypropylene compositions prepared in each example and comparative example were injection molded into flame retardant strips of 125mm×13mm×1.5mm and the flame retardant performance was tested according to UL94-2018. (2) Impact performance test: The polypropylene compositions prepared in each example and comparative example were injection molded into 80mm×10mm×4mm notched impact test specimens and impact tests were performed in accordance with GB / T 1843-2008.
[0063] Examples 1-8 and Comparative Examples 1-6 Table 1. Formulations (parts by weight) and properties of the fluorine-free and halogen-free flame-retardant polypropylene compositions in Examples 1-8
[0064] Formulations (parts by weight) and properties of the fluorine-free and halogen-free flame-retardant polypropylene compositions in Comparative Examples 1-6
[0065] As can be seen from Table 1, the fluorine-free and halogen-free flame-retardant polypropylene compositions prepared by this invention have good flame-retardant and mechanical properties. Specifically, they all achieve a flame retardancy of 1.5 mm V-0 and an impact resistance of ≥4 KJ / m. 2 .
[0066] As can be seen from Comparative Example 1, if the tangent tgδ of the loss angle δ of the added second polypropylene resin at 180°C and 0.1Hz is too high, the flame retardancy and mechanical properties of the resulting polypropylene composition will decrease, which is significantly worse than that of the example.
[0067] As can be seen from Comparative Example 2, the flame retardant properties of the prepared polypropylene composition cannot meet the requirements without the addition of active additives.
[0068] As can be seen from Comparative Examples 3-5, if a specific compounded flame retardant is not used, the flame retardant properties of the resulting polypropylene composition are significantly lower than those in the examples.
[0069] As can be seen from Comparative Example 6, the flame retardant and impact properties of the resulting polypropylene composition are significantly reduced if the second polypropylene resin is not added.
[0070] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.
Claims
1. A fluorine-free and halogen-free flame-retardant polypropylene composition, characterized in that, Includes the following components, calculated in parts by weight: 56-70 parts of the first polypropylene resin; 6-12 parts of the second polypropylene resin; 24-28 parts of compound flame retardant; 0.2 to 2 parts of active additives; Wherein, the second polypropylene resin has a loss angle tangent tgδ≤2 at 180℃ and a frequency of 0.1Hz; the compound flame retardant includes piperazine flame retardants, melamine salt flame retardants and phosphine / phosphate flame retardants.
2. The fluorine-free and halogen-free flame-retardant polypropylene composition according to claim 1, characterized in that, The active additive includes an acrylic metal salt; preferably, the active additive includes one or more of zinc acrylate, zinc methacrylate, or aluminum acrylate.
3. The fluorine-free and halogen-free flame-retardant polypropylene composition according to claim 1, characterized in that, The mass ratio of piperazine flame retardant, melamine salt flame retardant and phosphine / phosphate flame retardant in the compound flame retardant is (1.4~2.2):1:(0.3~0.6).
4. The fluorine-free and halogen-free flame-retardant polypropylene composition according to claim 1 or 3, characterized in that, The piperazine flame retardant includes one or more of piperazine phosphate, piperazine pyrophosphate, or piperazine polyphosphate; the melamine salt flame retardant includes melamine pyrophosphate flame retardant and / or melamine polyphosphate flame retardant; the phosphine / phosphate flame retardant includes one or more of aluminum hypophosphite, calcium hypophosphite, or aluminum diethylphosphite.
5. The fluorine-free and halogen-free flame-retardant polypropylene composition according to claim 1, characterized in that, The loss angle tangent tgδ of the second polypropylene resin at 180°C and 0.1Hz is 0.8~1.8; preferably, the loss angle tangent tgδ of the second polypropylene resin at 180°C and 0.1Hz is 1.0~1.
6.
6. The fluorine-free and halogen-free flame-retardant polypropylene composition according to claim 1, characterized in that, The melt flow rate of the polypropylene resin at 230°C and 2.16 kg load is ≥28 g / 10 min; preferably, the melt flow rate of the polypropylene resin at 230°C and 2.16 kg load is 30~70 g / 10 min.
7. The fluorine-free and halogen-free flame-retardant polypropylene composition according to claim 1, characterized in that, It also includes 0.5 to 2 parts of processing aids; the processing aids include one or more of antioxidants, lubricants or colorants.
8. A method for preparing the fluorine-free and halogen-free flame-retardant polypropylene composition according to any one of claims 1 to 7, characterized in that, Includes the following steps: The components are mixed evenly in proportion, and then melt-extruded and granulated to obtain a fluorine-free and halogen-free flame-retardant polypropylene composition.
9. The use of the fluorine-free and halogen-free flame-retardant polypropylene composition according to any one of claims 1 to 7 in the preparation of housing materials for household appliances.
10. A component, characterized in that, It is prepared using the fluorine-free and halogen-free flame-retardant polypropylene composition according to any one of claims 1 to 7.