Halogen-free flame-retardant polypropylene material and preparation method and application thereof

Abstract

The application discloses a kind of halogen-free flame-retardant polypropylene materials and preparation method, application, belong to high polymer material field.Its raw material includes by weight portion: polypropylene 50~70 parts, polymethyl methacrylate 15~30 parts, halogen-free flame retardant 15~20 parts, the total weight of polypropylene, polymethyl methacrylate and modified halogen-free flame retardant is 100 parts, compatible agent 3~8 parts, antioxidant 0.2 parts.The application is with polypropylene as main matrix, introduce PMMA material as scratch-resistant unit, using modified halogen-free flame retardant of pyrazine pyrophosphate system, with glycidyl methacrylate grafted polypropylene as efficient compatible agent, and halogen-free flame-retardant polypropylene material with excellent mechanical properties, high surface hardness, high scratch resistance, excellent flame-retardant property is prepared.

Description

Technical Field

[0001] This invention relates to the field of polymer materials, specifically to a halogen-free flame-retardant polypropylene material and its preparation method. Background Technology

[0002] Polypropylene (PP) materials possess excellent comprehensive mechanical properties, are odorless and non-toxic, and exhibit good chemical stability, outstanding ductility, resistance to flexural fatigue, ease of processing, easy recycling, and low production costs, making them widely used in home appliances, automobiles, and electronics. However, PP's disadvantages include its flammable carbon chain structure and low oxygen index, which limits its application in some electrically charged components. Therefore, flame-retardant modification is required in many applications. Traditional flame-retardant polypropylene materials typically incorporate halogenated flame retardants, but the gases produced during combustion are harmful to human health and cause significant environmental pollution, failing to meet environmental protection requirements. Therefore, the demand for halogen-free flame-retardant polypropylene materials is increasing. However, current halogen-free flame-retardant polypropylene materials require large amounts of halogen-free flame retardants, which significantly impact the overall performance of the product, making it difficult to simultaneously maintain optimal rigidity and toughness while meeting flame-retardant performance requirements.

[0003] Meanwhile, polypropylene (PP) material itself is relatively soft, especially after adding a large amount of halogen-free flame retardant, its performance decreases significantly. Products are easily scratched during transportation and use, severely affecting their appearance. Currently, researchers both domestically and internationally are improving scratch resistance by adding scratch-resistant additives such as PMMA, wollastonite, microfibers, silicone, and silica. While large additions can significantly improve scratch resistance, they can severely deteriorate the material's toughness or reduce its flame retardant properties. Toughness issues can lead to breakage or cracking of the product due to impacts during production, transportation, or user installation; flame retardant issues can result in failure to meet UL94 vertical burning requirements. Polymethyl methacrylate (PMMA), with a relative molecular mass of approximately 2 million and very soft molecular chains, has good hardness and high gloss, giving it a unique advantage in improving the scratch resistance of polypropylene. However, PP and PMMA have poor compatibility, and the mechanical properties obtained through ordinary blending are insufficient. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention proposes a halogen-free flame-retardant polypropylene material.

[0005] The objective of this invention can be achieved through the following technical solutions:

[0006] A halogen-free flame-retardant polypropylene material, characterized in that it comprises the following raw materials in parts by weight:

[0007] 50-70 parts of polypropylene.

[0008] 15-30 parts of polymethyl methacrylate

[0009] 15-20 parts of modified halogen-free flame retardant,

[0010] The total weight of polypropylene, polymethyl methacrylate, and modified halogen-free flame retardant is 100 parts.

[0011] 3-8 parts compatibilizer;

[0012] The compatibilizer is glycidyl methacrylate grafted polypropylene and / or ethylene-acrylate-glycidyl methacrylate.

[0013] Optionally, the halogen-free flame retardant is a piperazine pyrophosphate system flame retardant premixed with KH560 coupling agent.

[0014] Optionally, the raw materials may further include: 0.2 parts of antioxidant.

[0015] Optionally, the glycidyl methacrylate grafted polypropylene has a grafting rate of 0.5%-2%.

[0016] Optionally, the antioxidant is a compound of hindered phenolic antioxidants and phosphite antioxidants.

[0017] Optionally, the weight ratio of the hindered phenolic antioxidant to the phosphite antioxidant is 1:2.

[0018] A method for preparing a halogen-free flame-retardant polypropylene material includes the following steps:

[0019] (1) Weigh the raw materials according to the weight ratio.

[0020] 50-70 parts of polypropylene.

[0021] 15-30 parts of polymethyl methacrylate

[0022] 15-20 parts of modified halogen-free flame retardant,

[0023] The total weight of polypropylene, polymethyl methacrylate, and modified halogen-free flame retardant is 100 parts.

[0024] 3-8 parts compatibilizer

[0025] Antioxidant 0.2 parts,

[0026] (2) After weighing and mixing all the raw materials, add them to the twin-screw extruder.

[0027] (3) After extrusion, water cooling, drying and pelletizing are performed to obtain halogen-free flame-retardant polypropylene material.

[0028] Optionally, the processing technology is as follows: Zone 1 temperature 200-230℃, Zone 2 temperature 200-230℃, Zone 3 temperature 200-230℃, Zone 4 temperature 200-230℃, Zone 5 temperature 180-210℃, head temperature 200-210℃, and main machine speed 500 rpm.

[0029] Optionally, the halogen-free flame-retardant polypropylene material prepared by the method can be used in the housing of a heater, the bottom shell of an induction cooker, the housing of a multi-burner furnace, and an air conditioner.

[0030] The beneficial effects of this invention are:

[0031] The halogen-free flame-retardant polypropylene material of this invention has high surface hardness and excellent scratch resistance, as well as excellent mechanical properties and flame-retardant properties. It can be applied to household appliances such as heater shells, induction cooker bottom shells, and multi-burner furnace shells, and can also be extended to other household appliances such as air conditioners.

[0032] The method for preparing halogen-free polypropylene material provided by this invention has a simple and easy-to-control process, low equipment requirements, and uses commercially available processing equipment, resulting in low investment and facilitating industrial production. Attached Figure Description

[0033] The invention will now be further described with reference to the accompanying drawings.

[0034] Figure 1 For the purposes of this application: Flowchart of the preparation process for the modified halogen-free flame retardant

[0035] Figure 2 For the purposes of this application: Flowchart of the preparation process of halogen-free flame-retardant polypropylene material Detailed Implementation

[0036] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0037] In some examples of this application, a process flow for a modified halogen-free flame retardant is disclosed.

[0038] The modified halogen-free flame retardant can be obtained by first mixing the halogen-free flame retardant with 2% KH560 coupling agent at 90℃ for 5 minutes.

[0039] The materials selected for this experiment are as follows:

[0040] PP resin: 550J, CNOOC Shell; PMMA resin: CM205, Zhenjiang Chimei; compatibilizer: PP-g-GMA, Jia Yi Rong; halogen-free flame retardant: HF-800A, Zhongshan Sutebao Company; antioxidants: 1010 and 168, Ciba Specialty Chemicals Co., Ltd.

[0041] The halogen-free flame-retardant polypropylene material comprises the following raw materials by weight. The present invention will be further described in detail below with reference to the embodiments, but the embodiments of the present invention are not limited thereto.

[0042] Example 1

[0043] 64 parts of polypropylene

[0044] 15 parts polymethyl methacrylate

[0045] 20 parts of modified halogen-free flame retardant

[0046] The total weight of polypropylene, polymethyl methacrylate, and modified halogen-free flame retardant is 100 parts.

[0047] 3 parts compatibilizer

[0048] Antioxidant 0.2 parts.

[0049] The compatibilizers are glycidyl methacrylate grafted polypropylene and ethylene-acrylate-glycidyl methacrylate.

[0050] After mixing the above-mentioned raw materials in a high-speed mixer for 5 minutes, the mixture is placed in a twin-screw extruder. The processing steps are as follows: Zone 1 temperature 200-230℃, Zone 2 temperature 200-230℃, Zone 3 temperature 200-230℃, Zone 4 temperature 200-230℃, Zone 5 temperature 180-210℃, Die head temperature 200-210℃, and main extruder speed 500 rpm. The halogen-free flame-retardant polypropylene material is obtained by extrusion granulation.

[0051] Example 2

[0052] 60 parts of polypropylene

[0053] 20 parts of polymethyl methacrylate

[0054] 20 parts of modified halogen-free flame retardant

[0055] The total weight of polypropylene, polymethyl methacrylate, and modified halogen-free flame retardant is 100 parts.

[0056] 3 parts compatibilizer

[0057] Antioxidant 0.2 parts.

[0058] The compatibilizers are glycidyl methacrylate grafted polypropylene and ethylene-acrylate-glycidyl methacrylate.

[0059] After mixing the above-mentioned raw materials in a high-speed mixer for 5 minutes, the mixture is placed in a twin-screw extruder. The processing steps are as follows: Zone 1 temperature 200-230℃, Zone 2 temperature 200-230℃, Zone 3 temperature 200-230℃, Zone 4 temperature 200-230℃, Zone 5 temperature 180-210℃, Die head temperature 200-210℃, and main extruder speed 500 rpm. The halogen-free flame-retardant polypropylene material is obtained by extrusion granulation.

[0060] Example 3

[0061] 55 parts of polypropylene

[0062] 25 parts of polymethyl methacrylate

[0063] 20 parts of modified halogen-free flame retardant

[0064] The total weight of polypropylene, polymethyl methacrylate, and modified halogen-free flame retardant is 100 parts.

[0065] 3 parts compatibilizer

[0066] Antioxidant 0.2 parts.

[0067] The compatibilizers are glycidyl methacrylate grafted polypropylene and ethylene-acrylate-glycidyl methacrylate.

[0068] After mixing the above-mentioned raw materials in a high-speed mixer for 5 minutes, the mixture is placed in a twin-screw extruder. The processing steps are as follows: Zone 1 temperature 200-230℃, Zone 2 temperature 200-230℃, Zone 3 temperature 200-230℃, Zone 4 temperature 200-230℃, Zone 5 temperature 180-210℃, Die head temperature 200-210℃, and main extruder speed 500 rpm. The halogen-free flame-retardant polypropylene material is obtained by extrusion granulation.

[0069] Example 4

[0070] 50 parts of polypropylene

[0071] 30 parts of polymethyl methacrylate

[0072] 20 parts of modified halogen-free flame retardant

[0073] The total weight of polypropylene, polymethyl methacrylate, and modified halogen-free flame retardant is 100 parts.

[0074] 3 parts compatibilizer

[0075] Antioxidant 0.2 parts.

[0076] The compatibilizers are glycidyl methacrylate grafted polypropylene and ethylene-acrylate-glycidyl methacrylate.

[0077] After mixing the above-mentioned raw materials in a high-speed mixer for 5 minutes, the mixture is placed in a twin-screw extruder. The processing steps are as follows: Zone 1 temperature 200-230℃, Zone 2 temperature 200-230℃, Zone 3 temperature 200-230℃, Zone 4 temperature 200-230℃, Zone 5 temperature 180-210℃, Die head temperature 200-210℃, and main extruder speed 500 rpm. The halogen-free flame-retardant polypropylene material is obtained by extrusion granulation.

[0078] Example 4

[0079] 50 parts of polypropylene

[0080] 30 parts of polymethyl methacrylate

[0081] 20 parts of modified halogen-free flame retardant

[0082] The total weight of polypropylene, polymethyl methacrylate, and modified halogen-free flame retardant is 100 parts.

[0083] 3 parts compatibilizer

[0084] Antioxidant 0.2 parts.

[0085] The compatibilizers are glycidyl methacrylate grafted polypropylene and ethylene-acrylate-glycidyl methacrylate.

[0086] After mixing the above-mentioned raw materials in a high-speed mixer for 5 minutes, the mixture is placed in a twin-screw extruder. The processing steps are as follows: Zone 1 temperature 200-230℃, Zone 2 temperature 200-230℃, Zone 3 temperature 200-230℃, Zone 4 temperature 200-230℃, Zone 5 temperature 180-210℃, Die head temperature 200-210℃, and main extruder speed 500 rpm. The halogen-free flame-retardant polypropylene material is obtained by extrusion granulation.

[0087] Example 5

[0088] 70 parts of polypropylene

[0089] 15 parts polymethyl methacrylate

[0090] 15 parts of modified halogen-free flame retardant,

[0091] The total weight of polypropylene, polymethyl methacrylate, and modified halogen-free flame retardant is 100 parts.

[0092] 5 parts compatibilizer

[0093] Antioxidant 0.2 parts.

[0094] The compatibilizers are glycidyl methacrylate grafted polypropylene and ethylene-acrylate-glycidyl methacrylate.

[0095] After mixing the above-mentioned raw materials in a high-speed mixer for 5 minutes, the mixture is placed in a twin-screw extruder. The processing steps are as follows: Zone 1 temperature 200-230℃, Zone 2 temperature 200-230℃, Zone 3 temperature 200-230℃, Zone 4 temperature 200-230℃, Zone 5 temperature 180-210℃, Die head temperature 200-210℃, and main extruder speed 500 rpm. The halogen-free flame-retardant polypropylene material is obtained by extrusion granulation.

[0096] Example 6

[0097] 67 parts of polypropylene

[0098] 15 parts polymethyl methacrylate

[0099] 18 parts of modified halogen-free flame retardant,

[0100] The total weight of polypropylene, polymethyl methacrylate, and modified halogen-free flame retardant is 100 parts.

[0101] 8 parts compatibilizer

[0102] Antioxidant 0.2 parts.

[0103] The compatibilizers are glycidyl methacrylate grafted polypropylene and ethylene-acrylate-glycidyl methacrylate.

[0104] After mixing the above-mentioned raw materials in a high-speed mixer for 5 minutes, the mixture is placed in a twin-screw extruder. The processing steps are as follows: Zone 1 temperature 200-230℃, Zone 2 temperature 200-230℃, Zone 3 temperature 200-230℃, Zone 4 temperature 200-230℃, Zone 5 temperature 180-210℃, Die head temperature 200-210℃, and main extruder speed 500 rpm. The halogen-free flame-retardant polypropylene material is obtained by extrusion granulation.

[0105] Example 7

[0106] 65 parts of polypropylene

[0107] 20 parts of polymethyl methacrylate

[0108] 15 parts of modified halogen-free flame retardant,

[0109] The total weight of polypropylene, polymethyl methacrylate, and modified halogen-free flame retardant is 100 parts.

[0110] 5 parts compatibilizer

[0111] Antioxidant 0.2 parts.

[0112] The compatibilizers are glycidyl methacrylate grafted polypropylene and ethylene-acrylate-glycidyl methacrylate.

[0113] After mixing the above-mentioned raw materials in a high-speed mixer for 5 minutes, the mixture is placed in a twin-screw extruder. The processing steps are as follows: Zone 1 temperature 200-230℃, Zone 2 temperature 200-230℃, Zone 3 temperature 200-230℃, Zone 4 temperature 200-230℃, Zone 5 temperature 180-210℃, Die head temperature 200-210℃, and main extruder speed 500 rpm. The halogen-free flame-retardant polypropylene material is obtained by extrusion granulation.

[0114] Example 8

[0115] 62 parts of polypropylene

[0116] 15 parts polymethyl methacrylate

[0117] 18 parts of modified halogen-free flame retardant,

[0118] The total weight of polypropylene, polymethyl methacrylate, and modified halogen-free flame retardant is 100 parts.

[0119] 8 parts compatibilizer

[0120] Antioxidant 0.2 parts.

[0121] The compatibilizers are glycidyl methacrylate grafted polypropylene and ethylene-acrylate-glycidyl methacrylate.

[0122] After mixing the above-mentioned raw materials in a high-speed mixer for 5 minutes, the mixture is placed in a twin-screw extruder. The processing steps are as follows: Zone 1 temperature 200-230℃, Zone 2 temperature 200-230℃, Zone 3 temperature 200-230℃, Zone 4 temperature 200-230℃, Zone 5 temperature 180-210℃, Die head temperature 200-210℃, and main extruder speed 500 rpm. The halogen-free flame-retardant polypropylene material is obtained by extrusion granulation.

[0123] Example 9

[0124] 60 parts of polypropylene

[0125] 25 parts of polymethyl methacrylate

[0126] 15 parts of modified halogen-free flame retardant,

[0127] The total weight of polypropylene, polymethyl methacrylate, and modified halogen-free flame retardant is 100 parts.

[0128] 5 parts compatibilizer

[0129] Antioxidant 0.2 parts.

[0130] The compatibilizers are glycidyl methacrylate grafted polypropylene and ethylene-acrylate-glycidyl methacrylate.

[0131] After mixing the above-mentioned raw materials in a high-speed mixer for 5 minutes, the mixture is placed in a twin-screw extruder. The processing steps are as follows: Zone 1 temperature 200-230℃, Zone 2 temperature 200-230℃, Zone 3 temperature 200-230℃, Zone 4 temperature 200-230℃, Zone 5 temperature 180-210℃, Die head temperature 200-210℃, and main extruder speed 500 rpm. The halogen-free flame-retardant polypropylene material is obtained by extrusion granulation.

[0132] Example 10

[0133] 57 parts of polypropylene

[0134] 25 parts of polymethyl methacrylate

[0135] 18 parts of modified halogen-free flame retardant,

[0136] The total weight of polypropylene, polymethyl methacrylate, and modified halogen-free flame retardant is 100 parts.

[0137] 8 parts compatibilizer

[0138] Antioxidant 0.2 parts.

[0139] The compatibilizers are glycidyl methacrylate grafted polypropylene and ethylene-acrylate-glycidyl methacrylate.

[0140] After mixing the above-mentioned raw materials in a high-speed mixer for 5 minutes, the mixture is placed in a twin-screw extruder. The processing steps are as follows: Zone 1 temperature 200-230℃, Zone 2 temperature 200-230℃, Zone 3 temperature 200-230℃, Zone 4 temperature 200-230℃, Zone 5 temperature 180-210℃, Die head temperature 200-210℃, and main extruder speed 500 rpm. The halogen-free flame-retardant polypropylene material is obtained by extrusion granulation.

[0141] Example 11

[0142] 55 parts of polypropylene

[0143] 30 parts of polymethyl methacrylate

[0144] 15 parts of modified halogen-free flame retardant,

[0145] The total weight of polypropylene, polymethyl methacrylate, and modified halogen-free flame retardant is 100 parts.

[0146] 5 parts compatibilizer

[0147] Antioxidant 0.2 parts.

[0148] The compatibilizers are glycidyl methacrylate grafted polypropylene and ethylene-acrylate-glycidyl methacrylate.

[0149] After mixing the above-mentioned raw materials in a high-speed mixer for 5 minutes, the mixture is placed in a twin-screw extruder. The processing steps are as follows: Zone 1 temperature 200-230℃, Zone 2 temperature 200-230℃, Zone 3 temperature 200-230℃, Zone 4 temperature 200-230℃, Zone 5 temperature 180-210℃, Die head temperature 200-210℃, and main extruder speed 500 rpm. The halogen-free flame-retardant polypropylene material is obtained by extrusion granulation.

[0150] Example 12

[0151] 52 parts of polypropylene

[0152] 30 parts of polymethyl methacrylate

[0153] 18 parts of modified halogen-free flame retardant,

[0154] The total weight of polypropylene, polymethyl methacrylate, and modified halogen-free flame retardant is 100 parts.

[0155] 8 parts compatibilizer

[0156] Antioxidant 0.2 parts.

[0157] The compatibilizers are glycidyl methacrylate grafted polypropylene and ethylene-acrylate-glycidyl methacrylate.

[0158] After mixing the above-mentioned raw materials in a high-speed mixer for 5 minutes, the mixture is placed in a twin-screw extruder. The processing steps are as follows: Zone 1 temperature 200-230℃, Zone 2 temperature 200-230℃, Zone 3 temperature 200-230℃, Zone 4 temperature 200-230℃, Zone 5 temperature 180-210℃, Die head temperature 200-210℃, and main extruder speed 500 rpm. The halogen-free flame-retardant polypropylene material is obtained by extrusion granulation.

[0159] Comparative Example 1

[0160] 65 parts of polypropylene

[0161] 15 parts polymethyl methacrylate

[0162] 20 parts of modified halogen-free flame retardant

[0163] The total weight of polypropylene, polymethyl methacrylate, and modified halogen-free flame retardant is 100 parts.

[0164] 0 parts compatibilizer

[0165] Antioxidant 0.2 parts.

[0166] After mixing the above-mentioned raw materials in a high-speed mixer for 5 minutes, the mixture is placed in a twin-screw extruder. The processing steps are as follows: Zone 1 temperature 200-230℃, Zone 2 temperature 200-230℃, Zone 3 temperature 200-230℃, Zone 4 temperature 200-230℃, Zone 5 temperature 180-210℃, Die head temperature 200-210℃, and main extruder speed 500 rpm. The halogen-free flame-retardant polypropylene material is obtained by extrusion granulation.

[0167] Comparative Example 2

[0168] 50 parts of polypropylene

[0169] 30 parts of polymethyl methacrylate

[0170] 20 parts of modified halogen-free flame retardant

[0171] The total weight of polypropylene, polymethyl methacrylate, and modified halogen-free flame retardant is 100 parts.

[0172] 0 parts compatibilizer

[0173] Antioxidant 0.2 parts.

[0174] After mixing the above-mentioned raw materials in a high-speed mixer for 5 minutes, the mixture is placed in a twin-screw extruder. The processing steps are as follows: Zone 1 temperature 200-230℃, Zone 2 temperature 200-230℃, Zone 3 temperature 200-230℃, Zone 4 temperature 200-230℃, Zone 5 temperature 180-210℃, Die head temperature 200-210℃, and main extruder speed 500 rpm. The halogen-free flame-retardant polypropylene material is obtained by extrusion granulation.

[0175] Comparative Example 3

[0176] 85 parts of polypropylene

[0177] 0 parts of polymethyl methacrylate

[0178] 15 parts of modified halogen-free flame retardant,

[0179] The total weight of polypropylene, polymethyl methacrylate, and modified halogen-free flame retardant is 100 parts.

[0180] 3 parts compatibilizer

[0181] Antioxidant 0.2 parts.

[0182] The compatibilizers are glycidyl methacrylate grafted polypropylene and ethylene-acrylate-glycidyl methacrylate.

[0183] After mixing the above-mentioned raw materials in a high-speed mixer for 5 minutes, the mixture is placed in a twin-screw extruder. The processing steps are as follows: Zone 1 temperature 200-230℃, Zone 2 temperature 200-230℃, Zone 3 temperature 200-230℃, Zone 4 temperature 200-230℃, Zone 5 temperature 180-210℃, Die head temperature 200-210℃, and main extruder speed 500 rpm. The halogen-free flame-retardant polypropylene material is obtained by extrusion granulation.

[0184] Comparative Example 4

[0185] 85 parts of polypropylene

[0186] 0 parts of polymethyl methacrylate

[0187] 15 parts of modified halogen-free flame retardant,

[0188] The total weight of polypropylene, polymethyl methacrylate, and modified halogen-free flame retardant is 100 parts.

[0189] 8 parts compatibilizer

[0190] Antioxidant 0.2 parts.

[0191] The compatibilizers are glycidyl methacrylate grafted polypropylene and ethylene-acrylate-glycidyl methacrylate.

[0192] After mixing the above-mentioned raw materials in a high-speed mixer for 5 minutes, the mixture is placed in a twin-screw extruder. The processing steps are as follows: Zone 1 temperature 200-230℃, Zone 2 temperature 200-230℃, Zone 3 temperature 200-230℃, Zone 4 temperature 200-230℃, Zone 5 temperature 180-210℃, Die head temperature 200-210℃, and main extruder speed 500 rpm. The halogen-free flame-retardant polypropylene material is obtained by extrusion granulation.

[0193] Comparative Example 5

[0194] 55 parts of polypropylene

[0195] 30 parts of polymethyl methacrylate

[0196] Halogen-free flame retardant (unmodified) 15 parts,

[0197] The total weight of polypropylene, polymethyl methacrylate, and halogen-free flame retardant is 100 parts.

[0198] 8 parts compatibilizer

[0199] Antioxidant 0.2 parts.

[0200] The compatibilizers are glycidyl methacrylate grafted polypropylene and ethylene-acrylate-glycidyl methacrylate.

[0201] Comparative Example 6

[0202] 64 parts of polypropylene

[0203] 15 parts polymethyl methacrylate

[0204] 20 parts of modified halogen-free flame retardant

[0205] The total weight of polypropylene, polymethyl methacrylate, and modified halogen-free flame retardant is 100 parts.

[0206] 3 parts compatibilizer

[0207] Antioxidant 0.2 parts.

[0208] The compatibilizer is glycidyl methacrylate grafted polypropylene.

[0209] After mixing the above-mentioned raw materials in a high-speed mixer for 5 minutes, the mixture is placed in a twin-screw extruder. The processing steps are as follows: Zone 1 temperature 200-230℃, Zone 2 temperature 200-230℃, Zone 3 temperature 200-230℃, Zone 4 temperature 200-230℃, Zone 5 temperature 180-210℃, Die head temperature 200-210℃, and main extruder speed 500 rpm. The halogen-free flame-retardant polypropylene material is obtained by extrusion granulation.

[0210] After mixing the above-mentioned raw materials in a high-speed mixer for 5 minutes, the mixture is placed in a twin-screw extruder. The processing parameters are as follows: Zone 1 temperature 200-230℃, Zone 2 temperature 200-230℃, Zone 3 temperature 200-230℃, Zone 4 temperature 200-230℃, Zone 5 temperature 180-210℃, Die head temperature 200-210℃, and main extruder speed 500 rpm. Extrusion granulation yields halogen-free flame-retardant polypropylene material.

[0211] The materials used in the above embodiments and comparative examples are shown in Table 1.

[0212] Table 1

[0213]

[0214] The halogen-free flame-retardant polypropylene materials prepared in Examples 1-12 and Comparative Examples 1-5 were injection molded into specimens and their performance was tested according to the following standard methods. The test results are shown in Table 2.

[0215] Tensile properties: Tested according to GB / T 1040-2006 standard, the tensile rate is 50 mm / min;

[0216] Bending performance: Tested according to GB / T 9341-2008 standard, with a strip thickness of 4mm;

[0217] Notched impact strength of cantilever beam: tested according to GB / T 1843-2008 standard, with a sample thickness of 4mm;

[0218] Flame retardant performance: Tested according to UL-94 standard, with a sample thickness of 2.0 mm;

[0219] Rockwell hardness: tested according to GB / T 230.1-2009 standard;

[0220] Scratch resistance: Tested according to GMW 14688-2012 standard, with 10N selected for the test. The color difference before and after scratch resistance is used to represent the scratch resistance. The smaller the color difference before and after scratch resistance, the stronger the scratch resistance of the material.

[0221] Table 2 Sample Test Results

[0222]

[0223] As shown in Examples 1-12, using polypropylene as the base resin, PMMA as the main scratch-resistant unit, adding a halogen-free flame retardant based on a modified piperazine pyrophosphate system, and using glycidyl methacrylate-grafted polypropylene (PP-g-GMA) as a compatibilizer, the hardness and scratch resistance of the material can be significantly improved, while the resulting material has excellent mechanical properties and flame retardant properties.

[0224] Examples 1-12 involve adjusting the proportions of polypropylene resin, PMMA resin, compatibilizer, modified halogen-free flame retardant, and antioxidant. As shown in the table, within a certain range, decreasing the polypropylene resin content (increasing the PMMA resin content) slightly increases the tensile strength, flexural strength, hardness, and scratch resistance of the material. After the PMMA resin content reaches a certain value, the hardness and scratch resistance tend to stabilize. Within a certain range, increasing the compatibilizer improves the tensile strength, flexural strength, and toughness of the material to a certain extent; after increasing to a certain amount, the resin content tends to stabilize.

[0225] By comparing Examples 5, 7, 9, and 11 with Comparative Examples 3, 4, and 6, it can be found that the addition of PMMA resin significantly improves various mechanical properties of the material; it exhibits excellent flame retardant properties with a small amount of halogen-free flame retardant added; at the same time, the addition of PMMA resin also significantly improves the material's scratch resistance and Rockwell hardness.

[0226] By comparing Examples 1, 5, and 6 with Comparative Example 1, it can be found that the compatibilizer can significantly improve the mechanical properties of polypropylene and PMMA resin, indicating that the introduction of the compatibilizer can improve the compatibility of polypropylene and PMMA resin.

[0227] By comparing Example 11 with Comparative Example 5, it can be found that modifying the halogen-free flame retardant with KH560 can improve the compatibility and dispersibility of the flame retardant in the resin, and it has excellent flame retardant performance with a small amount of halogen-free flame retardant added.

[0228] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0229] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed invention.

Claims

1. A halogen-free flame-retardant polypropylene material, characterized in that, Including the following parts by weight of raw materials: 50-70 parts of polypropylene 15-30 parts of polymethyl methacrylate, 15-20 parts of modified halogen-free flame retardant, The total weight of polypropylene, polymethyl methacrylate, and modified halogen-free flame retardant is 100 parts. 3-8 parts compatibilizer; The compatibilizer is glycidyl methacrylate grafted polypropylene and / or ethylene-acrylate-glycidyl methacrylate. The modified halogen-free flame retardant is a piperazine pyrophosphate system flame retardant premixed with KH560 coupling agent.

2. The halogen-free flame-retardant polypropylene material according to claim 1, characterized in that, The ingredients also include: 0.2 parts antioxidant.

3. The halogen-free flame-retardant polypropylene material according to claim 1, characterized in that, The glycidyl methacrylate-grafted polypropylene has a grafting rate of 0.5%-2%.

4. The halogen-free flame-retardant polypropylene material according to claim 2, characterized in that, The antioxidant is a compound of hindered phenolic antioxidants and phosphite antioxidants.

5. The halogen-free flame-retardant polypropylene material according to claim 4, characterized in that, The weight ratio of the hindered phenolic antioxidant to the phosphite antioxidant is 1:

2.

6. A method for preparing a halogen-free flame-retardant polypropylene material, characterized in that, Includes the following steps: Weigh the raw materials according to the specified weight ratio. 50-70 parts of polypropylene 15-30 parts of polymethyl methacrylate, 15-20 parts of modified halogen-free flame retardant, The total weight of polypropylene, polymethyl methacrylate, and modified halogen-free flame retardant is 100 parts. 3-8 parts compatibilizer Antioxidant 0.2 parts, After weighing and mixing all the raw materials evenly, add them to the twin-screw extruder. After extrusion, water cooling, drying, and pelletizing yield halogen-free flame-retardant polypropylene material.

7. The method for preparing halogen-free flame-retardant polypropylene material according to claim 6, characterized in that, The processing technology is as follows: Zone 1 temperature 200-230℃, Zone 2 temperature 200-230℃, Zone 3 temperature 200-230℃, Zone 4 temperature 200-230℃, Zone 5 temperature 180-210℃, head temperature 200-210℃, and main machine speed 500 rpm.

8. The application of the halogen-free flame-retardant polypropylene material according to any one of claims 1-5 or the halogen-free flame-retardant polypropylene material prepared by the method according to claims 6 or 7 in the housing of a heater, the bottom shell of an induction cooker, the housing of a multi-burner furnace, and an air conditioner.

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