Flame-retardant polypropylene composite material and preparation method thereof

Abstract

The invention discloses a flame-retardant polypropylene composite material and a preparation method thereof, and belongs to the technical field of high polymer materials, the flame-retardant polypropylene composite material comprises the following raw materials by weight: 40-60 parts of PP resin, 10-20 parts of POE resin, 10-15 parts of PE resin, 15-20 parts of a flame retardant, 4-10 parts of a synergistic flame retardant, 4-10 parts of talcum powder, 2-5 parts of carbon black, 0.5-2 parts of a dispersant, and 1-4 parts of an auxiliary agent; the preparation method comprises the following steps: drying the raw materials, adding the dried raw materials into a double-screw extruder, and extruding at the temperature of 180-220 DEG C and the rotating speed of 100-150r / min to obtain the flame-retardant polypropylene composite material. By adding the flame retardant and the synergistic flame retardant, the composite material can be endowed with excellent flame retardant property, the flame retardant contains a POSS structure, vanillin and a 9, 10-dihydro-9-oxo-10-phosphoric acid-10-oxide structure, and ternary synergistic flame retardance can be realized when the flame retardant is added into a matrix.

Description

Technical Field

[0001] The invention relates to the technical field of polymer materials, and in particular to a flame retardant polypropylene composite material and a preparation method thereof. Background Art

[0002] Polypropylene has excellent properties such as low thermoplastic temperature, low relative density, non-toxicity, light weight, and heat resistance. It is one of the most widely used general plastics. However, since polypropylene is a polyolefin compound, it is easy to burn and there are huge safety hazards. In order to solve this defect of polypropylene, many scholars at home and abroad have conducted a lot of research on flame-retardant polypropylene composite materials. Halogen flame retardants are the most widely used now, but halogen flame retardants will release a lot of smoke and hydrogen halide gas after combustion, which makes it difficult to extinguish fires, and the generated hydrogen halide gas will cause serious pollution to the environment. At present, there are also halogen-free flame retardants. Commonly used halogen-free flame retardants include ordinary intumescent flame retardants and hydroxide flame retardants, which have low flame retardant efficiency and also reduce the mechanical properties of composite materials.

[0003] Among the numerous halogen-free flame retardants, phosphorus-based flame retardants have become a research hotspot in the field of flame retardancy. Phosphorus-containing phenanthrene compounds and their derivatives are a new type of flame retardant with excellent flame retardant properties and are widely used in polymer-based halogen-free flame retardant composite materials. Phosphorus-containing phenanthrene not only has better thermal and chemical stability than general un-annulated organic phosphates, but also has the advantages of low phosphorus content, halogen-free, low smoke, non-toxic, non-migrating and long-lasting flame retardancy. However, phosphorus-based flame retardants also have their shortcomings. The carbon layer structure strength and density of this type of flame retardant after combustion are poor, and the oxygen and heat insulation capabilities are weak; moreover, this type of flame retardant has poor compatibility with the polymer matrix or reinforcing materials, which reduces the mechanical properties of this type of flame retardant when used; the flame retardant effect of phosphorus-containing phenanthrene flame retardants and their derivatives is mainly gas phase flame retardant, and the condensed phase flame retardant effect is relatively weak. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides a flame retardant polypropylene composite material and a preparation method thereof.

[0005] The purpose of the present invention can be achieved through the following technical solutions:

[0006] A flame-retardant polypropylene composite material, comprising the following raw materials in parts by weight: 40-60 parts of PP resin, 10-20 parts of POE resin, 10-15 parts of PE resin, 15-20 parts of flame retardant, 4-10 parts of synergistic flame retardant, 4-10 parts of talc, 2-5 parts of carbon black, 0.5-2 parts of dispersant, and 1-4 parts of additives;

[0007] The flame retardant is prepared by the following steps:

[0008] Step S1, adding propanol, acetonitrile and tetramethylammonium hydroxide to deionized water, stirring at a uniform speed to obtain solution a, slowly adding aminopropyltriethoxysilane, heating to 45-50°C, keeping warm and reacting for 12 hours, adding an equal volume of tetrahydrofuran to precipitate after the reaction, washing three times with deionized water and n-hexane respectively, and drying at 85°C to obtain an intermediate, wherein the amount ratio of propanol, acetonitrile, tetramethylammonium hydroxide, aminopropyltriethoxysilane and deionized water is controlled to be 20-40mL:5-10mL:1-2mL:50-100g:100mL;

[0009] In step S1, aminopropyltriethoxysilane is used as a raw material to synthesize an intermediate, which is polyamino POSS;

[0010] Step S2, adding the intermediate and vanillin to anhydrous ethanol, heating to 80-85°C, stirring at a uniform speed and reacting for 8 hours, then adding 9,10-dihydro-9-oxygen-10-phosphoric acid-10-oxide, keeping the temperature and continuing to react for 18 hours, and obtaining a flame retardant after the reaction is completed, and controlling the dosage ratio of the intermediate 1, vanillin, 9,10-dihydro-9-oxygen-10-phosphoric acid-10-oxide and anhydrous ethanol to be 0.01-0.02 mmol: 0.05-0.1 mmol: 0.05-0.1 mmol: 100 mL.

[0011] The amino group on the intermediate of step S2 reacts with vanillin to form a carbon-nitrogen double bond, and then 9,10-dihydro-9-oxygen-10-phosphoric acid-10-oxide is added, and the active phosphorus-hydrogen bond on the 9,10-dihydro-9-oxygen-10-phosphoric acid-10-oxide reacts with the carbon-nitrogen double bond, and then the 9,10-dihydro-9-oxygen-10-phosphoric acid-10-oxide is connected to the intermediate structure to obtain a flame retardant. The flame retardant contains a POSS structure, vanillin and a 9,10-dihydro-9-oxygen-10-phosphoric acid-10-oxide structure. When the flame retardant is added to the matrix, the synergistic effect of the POSS and the 9,10-dihydro-9-oxygen-10-phosphoric acid-10-oxide structure is used to give the polypropylene matrix excellent flame retardant properties. Moreover, the vanillin can be used as a connecting bridge on the one hand, and a benzene ring can be introduced on the other hand, so as to further improve the carbon-forming performance of the flame retardant, improve the flame retardant effect, and achieve ternary synergistic flame retardancy.

[0012] Furthermore, the synergistic flame retardant is a mixture of inorganic powder and zinc-containing inorganic compound in a weight ratio of 1:1.

[0013] Furthermore, the inorganic powder is one or more of kaolin, montmorillonite or clay mixed in any proportion; the zinc-containing inorganic compound is one or more of zinc borate, zinc stannate, zinc aluminate and zinc oxide mixed in any proportion.

[0014] Furthermore, the dispersant is stearic acid or calcium stearate.

[0015] Furthermore, the auxiliary agent is antioxidant 168 or antioxidant 1010.

[0016] A method for preparing a flame retardant polypropylene composite material comprises the following steps:

[0017] After drying the raw materials, add them into a twin-screw extruder, extrude them at a temperature of 180-220° C. and a rotation speed of 100-150 rpm to obtain a flame-retardant polypropylene composite material.

[0018] Beneficial effects of the present invention:

[0019] The invention prepares a flame-retardant polypropylene composite material, and excellent flame retardant performance can be given to the composite material by adding a flame retardant and a synergistic flame retardant, wherein in the preparation process of the flame retardant, aminopropyltriethoxysilane is first used as a raw material to synthesize an intermediate, which is polyamino POSS, and then the amino group on the intermediate reacts with vanillin to form a carbon-nitrogen double bond, and then 9,10-dihydro-9-oxygen-10-phosphoric acid-10-oxide is added, and the active phosphorus-hydrogen bond on the 9,10-dihydro-9-oxygen-10-phosphoric acid-10-oxide reacts with the carbon-nitrogen double bond, thereby 9,10-dihydro- 9-Oxygen-10-phosphoric acid-10-oxide is connected to an intermediate structure to prepare a flame retardant. The flame retardant contains a POSS structure, vanillin and a 9,10-dihydro-9-oxygen-10-phosphoric acid-10-oxide structure. When added to a matrix, the synergistic effect of the POSS and the 9,10-dihydro-9-oxygen-10-phosphoric acid-10-oxide structure gives the polypropylene matrix excellent flame retardant performance. Moreover, the vanillin can be used as a connecting bridge on the one hand, and a benzene ring can be introduced on the other hand, so as to further improve the carbon-forming performance of the flame retardant, improve the flame retardant effect, and realize ternary synergistic flame retardancy. DETAILED DESCRIPTION

[0020] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0021] Example 1: A flame retardant polypropylene composite material, comprising the following raw materials in parts by weight: 40 parts of PP resin, 10 parts of POE resin, 10 parts of PE resin, 15 parts of flame retardant, 4 parts of synergistic flame retardant, 4 parts of talc, 2 parts of carbon black, 0.5 parts of dispersant, and 1 part of auxiliary agent;

[0022] A method for preparing a flame retardant polypropylene composite material comprises the following steps:

[0023] After drying the raw materials, add them into a twin-screw extruder and extrude them at a temperature of 180-220° C. and a rotation speed of 100 revolutions per minute to obtain a flame-retardant polypropylene composite material.

[0024] The synergistic flame retardant is a mixture of inorganic powder and zinc-containing inorganic compound in a weight ratio of 1:1.

[0025] The inorganic powder is kaolin; and the zinc-containing inorganic compound is zinc borate.

[0026] The dispersant is stearic acid.

[0027] The auxiliary agent is antioxidant 168.

[0028] The flame retardant is prepared by the following steps:

[0029] Step S1, adding propanol, acetonitrile and tetramethylammonium hydroxide to deionized water, stirring at a uniform speed to obtain solution a, slowly adding aminopropyltriethoxysilane, heating to 45°C, keeping warm and reacting for 12 hours, adding an equal volume of tetrahydrofuran after the reaction to precipitate, washing with deionized water and n-hexane three times respectively, drying at 85°C to obtain an intermediate, and controlling the amount ratio of propanol, acetonitrile, tetramethylammonium hydroxide, aminopropyltriethoxysilane and deionized water to be 20mL:5mL:1mL:50g:100mL;

[0030] Step S2, adding the intermediate and vanillin to anhydrous ethanol, heating to 80°C, stirring at a uniform speed and reacting for 8 hours, then adding 9,10-dihydro-9-oxygen-10-phosphoric acid-10-oxide, keeping warm and continuing to react for 18 hours, and obtaining a flame retardant after the reaction, wherein the amount ratio of the intermediate 1, vanillin, 9,10-dihydro-9-oxygen-10-phosphoric acid-10-oxide and anhydrous ethanol is controlled to be 0.01 mmol: 0.05 mmol: 0.05 mmol: 100 mL.

[0031] Example 2: A flame retardant polypropylene composite material, comprising the following raw materials in parts by weight: 50 parts of PP resin, 115 parts of POE resin, 12 parts of PE resin, 18 parts of flame retardant, 6 parts of synergistic flame retardant, 8 parts of talc, 3 parts of carbon black, 1.2 parts of dispersant, and 2 parts of additives;

[0032] A method for preparing a flame retardant polypropylene composite material comprises the following steps:

[0033] After drying the raw materials, add them into a twin-screw extruder, extrude them at a temperature of 180-220° C. and a rotation speed of 100-150 rpm to obtain a flame-retardant polypropylene composite material.

[0034] The synergistic flame retardant is a mixture of inorganic powder and zinc-containing inorganic compound in a weight ratio of 1:1.

[0035] The inorganic powder is one or more of kaolin, montmorillonite or clay mixed in any proportion; the zinc-containing inorganic compound is one or more of zinc borate, zinc stannate, zinc aluminate and zinc oxide mixed in any proportion.

[0036] The dispersant is stearic acid.

[0037] The auxiliary agent is antioxidant 1010.

[0038] The flame retardant is prepared by the following steps:

[0039] Step S1, adding propanol, acetonitrile and tetramethylammonium hydroxide to deionized water, stirring at a uniform speed to obtain solution a, slowly adding aminopropyltriethoxysilane, heating to 50°C, keeping warm and reacting for 12 hours, adding an equal volume of tetrahydrofuran to precipitate after the reaction, washing three times with deionized water and n-hexane respectively, and drying at 85°C to obtain an intermediate, wherein the amount ratio of propanol, acetonitrile, tetramethylammonium hydroxide, aminopropyltriethoxysilane and deionized water is controlled to be 30mL:8mL:1.5mL:80g:100mL;

[0040] Step S2, adding the intermediate and vanillin to anhydrous ethanol, heating to 82° C., stirring at a uniform speed and reacting for 8 hours, then adding 9,10-dihydro-9-oxygen-10-phosphoric acid-10-oxide, keeping the temperature and continuing the reaction for 18 hours, and obtaining a flame retardant after the reaction, wherein the amount ratio of the intermediate 1, vanillin, 9,10-dihydro-9-oxygen-10-phosphoric acid-10-oxide and anhydrous ethanol is controlled to be 0.015 mmol: 0.08 mmol: 0.08 mmol: 100 mL.

[0041] Example 3: A flame retardant polypropylene composite material, comprising the following raw materials in parts by weight: 60 parts of PP resin, 20 parts of POE resin, 15 parts of PE resin, 20 parts of flame retardant, 10 parts of synergistic flame retardant, 10 parts of talc, 5 parts of carbon black, 2 parts of dispersant, and 4 parts of additives;

[0042] A method for preparing a flame retardant polypropylene composite material comprises the following steps:

[0043] After drying the raw materials, add them into a twin-screw extruder and extrude them at a temperature of 180° C.-220° C. and a rotation speed of 150 rpm to obtain a flame-retardant polypropylene composite material.

[0044] The synergistic flame retardant is a mixture of inorganic powder and zinc-containing inorganic compound in a weight ratio of 1:1.

[0045] The inorganic powder is one or more of kaolin, montmorillonite or clay mixed in any proportion; the zinc-containing inorganic compound is one or more of zinc borate, zinc stannate, zinc aluminate and zinc oxide mixed in any proportion.

[0046] The dispersant is calcium stearate.

[0047] The auxiliary agent is antioxidant 1010.

[0048] The flame retardant is prepared by the following steps:

[0049] Step S1, adding propanol, acetonitrile and tetramethylammonium hydroxide to deionized water, stirring at a uniform speed to obtain solution a, slowly adding aminopropyltriethoxysilane, heating to 50°C, keeping warm and reacting for 12 hours, adding an equal volume of tetrahydrofuran after the reaction to precipitate, washing with deionized water and n-hexane three times respectively, drying at 85°C to obtain an intermediate, and controlling the amount ratio of propanol, acetonitrile, tetramethylammonium hydroxide, aminopropyltriethoxysilane and deionized water to be 40mL:10mL:2mL:100g:100mL;

[0050] Step S2, adding the intermediate and vanillin to anhydrous ethanol, heating to 85°C, stirring at a uniform speed and reacting for 8 hours, then adding 9,10-dihydro-9-oxygen-10-phosphoric acid-10-oxide, keeping warm and continuing to react for 18 hours, and obtaining a flame retardant after the reaction, wherein the amount ratio of the intermediate 1, vanillin, 9,10-dihydro-9-oxygen-10-phosphoric acid-10-oxide and anhydrous ethanol is controlled to be 0.02 mmol: 0.1 mmol: 0.1 mmol: 100 mL.

[0051] Comparative Example 1: Compared with Example 1, this comparative example uses 9,10-dihydro-9-oxygen-10-phosphoric acid-10-oxide as a flame retardant, and the rest is the same as Example 1.

[0052] The properties of the flame-retardant polypropylene composite materials prepared in Examples 1 to 3 and the comparative example were tested: wherein the vertical combustion performance test method in GB / T2408-2008 "Horizontal and vertical methods for determination of combustion performance of plastics" was used to perform the vertical combustion performance test.

[0053] GB / T2406.2-2009 "Determination of Combustion Behavior of Plastics by Oxygen Index Method Part 2: Room Temperature Test" conducts oxygen index test. The test data is shown in Table 1 below:

[0054] Table 1

[0055] Example 1 Example 2 Example 3 Comparative Example 1 LOI 34 33 34 25 UL94 V0 V0 V0 V1

[0056] It can be seen from Table 1 above that Examples 1-3 of the present invention have excellent flame retardant properties. Therefore, when the flame retardant of the present invention is added to the matrix, the synergistic effect of POSS and 9,10-dihydro-9-oxygen-10-phosphoric acid-10-oxide structure gives the polypropylene matrix excellent flame retardant properties. In addition, vanillin can serve as a connecting bridge on the one hand, and on the other hand, it can introduce a benzene ring, further improving the carbon-forming performance of the flame retardant, improving the flame retardant effect, and achieving ternary synergistic flame retardancy.

[0057] The above contents are merely examples and explanations of the concept of the present invention. The technicians in this technical field may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the concept of the invention or exceed the scope defined by the claims, they should all fall within the protection scope of the present invention.

Claims

1. A flame retardant polypropylene composite material, characterized in that: The composition comprises the following raw materials in parts by weight: 40-60 parts of PP resin, 10-20 parts of POE resin, 10-15 parts of PE resin, 15-20 parts of flame retardant, 4-10 parts of synergistic flame retardant, 4-10 parts of talc powder, 2-5 parts of carbon black, 0.5-2 parts of dispersant, and 1-4 parts of additives; The flame retardant is prepared by the following steps: Step S1, adding propanol, acetonitrile and tetramethylammonium hydroxide into deionized water, stirring at a uniform speed to obtain solution a, slowly adding aminopropyltriethoxysilane, heating to 45-50° C., keeping the temperature and reacting for 12 hours, adding an equal volume of tetrahydrofuran to precipitate after the reaction, washing with deionized water and n-hexane three times respectively, and drying at 85° C. to obtain an intermediate; Step S2, adding the intermediate and vanillin into anhydrous ethanol, heating to 80-85° C., stirring at a uniform speed and reacting for 8 hours, then adding 9,10-dihydro-9-oxygen-10-phosphoric acid-10-oxide, keeping the temperature and continuing the reaction for 18 hours, and obtaining a flame retardant after the reaction is completed.

2. The flame retardant polypropylene composite material according to claim 1, characterized in that: The synergistic flame retardant is a mixture of inorganic powder and zinc-containing inorganic compound in a weight ratio of 1:

1.

3. The flame retardant polypropylene composite material according to claim 1, characterized in that: The inorganic powder is one or more of kaolin, montmorillonite or clay mixed in any proportion; the zinc-containing inorganic compound is one or more of zinc borate, zinc stannate, zinc aluminate and zinc oxide mixed in any proportion.

4. The flame retardant polypropylene composite material according to claim 1, characterized in that: The dispersant is stearic acid or calcium stearate.

5. The flame retardant polypropylene composite material according to claim 1, characterized in that: The auxiliary agent is antioxidant 168 or antioxidant 1010.

6. The flame retardant polypropylene composite material according to claim 1, characterized in that: In step S1, the dosage ratio of propanol, acetonitrile, tetramethylammonium hydroxide, aminopropyltriethoxysilane and deionized water is controlled to be 20-40 mL: 5-10 mL: 1-2 mL: 50-100 g: 100 mL.

7. The flame retardant polypropylene composite material according to claim 1, characterized in that: In step S2, the dosage ratio of intermediate 1, vanillin, 9,10-dihydro-9-oxo-10-phosphoric acid-10-oxide and anhydrous ethanol is controlled to be 0.01-0.02 mmol: 0.05-0.1 mmol: 0.05-0.1 mmol: 100 mL.

8. The method for preparing a flame retardant polypropylene composite material according to claim 1, characterized in that: The steps include: After drying the raw materials, add them into a twin-screw extruder, extrude them at a temperature of 180-220° C. and a rotation speed of 100-150 rpm to obtain a flame-retardant polypropylene composite material.