Light-color and colored high-performance organophosphorus flame-retardant polyamide composite material capable of being marked by laser and preparation method thereof

Abstract

The invention provides a light-color and colored high-performance organophosphorus flame-retardant polyamide composite material capable of being marked by laser, which comprises the following components: polyamide, modified glass fiber, an organophosphorus flame retardant, modified titanium dioxide, a laser marking auxiliary agent and an auxiliary agent, wherein the modified glass fiber is obtained by reacting glass fiber, a silane coupling agent and double-bond-terminated polyesteramide; the modified titanium dioxide is obtained by reaction of titanium dioxide and trihydroxy ethane. According to the modified glass fiber disclosed by the invention, polyesteramide, aryl and other groups are introduced into the glass fiber, so that the compatibility of the glass fiber and organic components is enhanced, and the adverse effect of glass fiber aggregation on the product performance is avoided; moreover, the modified titanium dioxide enables the titanium dioxide to be grafted with organic groups containing a large number of hydroxyl groups, titanium dioxide agglomeration is prevented, the titanium dioxide and the laser marking assistant wrapping the titanium dioxide can be uniformly dispersed, the bonding strength with other components can be improved through intermolecular acting force, and the performance of the product is improved.

Description

Technical Field

[0001] The invention relates to the technical field of polymer materials, and mainly relates to a laser-markable, light-colored and colorful high-performance organic phosphorus flame-retardant polyamide composite material and a preparation method thereof. Background Art

[0002] Laser-markable, light-colored and colorful high-performance organophosphorus flame-retardant polyamide composite materials are polymer materials with specific functions and properties, and their main components include polyamide matrix, organophosphorus flame retardant, laser marking additives, etc. Laser-markable, light-colored and colorful high-performance organophosphorus flame-retardant polyamide composite materials generally use polyamide as the matrix material. Polyamide is also commonly known as nylon, which is an important type of polymer material with good mechanical properties, wear resistance, chemical corrosion resistance and thermal stability, etc. It provides basic physical and mechanical performance support for the entire composite material and is the basis for other components to play a role. Organophosphorus flame retardant is a key functional additive in the composite material with good flame retardant properties. It can effectively inhibit the combustion of materials, reduce the flammability and burning rate of materials, and improve the fire safety performance of materials by playing a variety of action mechanisms such as gas phase flame retardant and condensed phase flame retardant during the combustion process. Common organophosphorus flame retardants include phosphates, phosphonates, phosphites, etc. Laser marking additives can enable composite materials to achieve laser marking functions. These additives can undergo specific physical or chemical changes under laser irradiation, thereby producing obvious marking effects, such as color changes, surface morphology changes, etc. Laser-markable, light-colored and colorful high-performance organophosphorus flame-retardant polyamide composites have good comprehensive properties and are widely used in many fields such as electronics, automobiles, aerospace, etc.

[0003] However, laser-markable, light-colored and colorful high-performance organophosphorus flame-retardant polyamide composites also have some disadvantages, such as: (1) ordinary laser marking additives can easily cause discoloration of organophosphorus flame-retardant polyamide; (2) uneven dispersion of glass fibers has a negative impact on the mechanical properties of polyamide materials; (3) agglomerated titanium dioxide has a negative impact on the mechanical properties of glass fiber reinforced polyamide materials.

[0004] Therefore, there is an urgent need to develop a new type of laser-markable, light-colored and colorful high-performance organophosphorus flame-retardant polyamide composite material to solve the current problems. Summary of the invention

[0005] The present invention provides a laser-markable, light-colored and colorful high-performance organic phosphorus flame-retardant polyamide composite material and a preparation method thereof. The compatibility of each component is improved by preparing modified glass fiber and modified titanium dioxide, and the problems existing in existing products such as common laser marking additives easily causing discoloration of organic phosphorus flame-retardant polyamide, uneven dispersion of glass fiber having a negative impact on the mechanical properties of polyamide materials, and agglomerated titanium dioxide having a negative impact on the mechanical properties of glass fiber reinforced polyamide materials can be well solved.

[0006] One object of the present invention is to provide a laser-markable, light-colored and colorful high-performance organic phosphorus flame-retardant polyamide composite material, wherein the laser-markable, light-colored and colorful high-performance organic phosphorus flame-retardant polyamide composite material comprises the following components in mass fraction:

[0007]

[0008] Wherein, the modified glass fiber is obtained by reacting glass fiber, silane coupling agent and double-bond terminated polyamide ester;

[0009] The modified titanium dioxide is obtained by reacting titanium dioxide and trihydroxyethane.

[0010] Furthermore, the silane coupling agent is a silane coupling agent containing a double bond.

[0011] Furthermore, the organic phosphorus flame retardant is a diethyl aluminum hypophosphite composite flame retardant.

[0012] Furthermore, the auxiliary agent is selected from one or more of lubricants, antioxidants, weathering agents, and pigments.

[0013] Furthermore, the laser marking auxiliary agent is titanium dioxide coated zinc sulfide.

[0014] Another object of the present invention is to provide a method for preparing the above-mentioned laser-markable, light-colored and colorful high-performance organic phosphorus flame-retardant polyamide composite material, the method for preparing the laser-markable, light-colored and colorful high-performance organic phosphorus flame-retardant polyamide composite material comprising the following steps:

[0015] S1, mixing glass fiber and nitric acid and heating to obtain activated glass fiber, then mixing with a silane coupling agent and heating to react to obtain an intermediate product, and finally mixing with a double-bond terminated polyamide ester and an initiator and heating and stirring to react to obtain a modified glass fiber;

[0016] S2, mixing titanium dioxide and trihydroxyethane, and drying to obtain modified titanium dioxide;

[0017] S3, blending polyamide, the modified glass fiber, the organophosphorus flame retardant, the modified titanium dioxide, the laser marking aid, and the additive, adding them into a twin-screw extruder, and melt-extruding and granulating them at 200-280°C to obtain the laser-markable, light-colored and colorful high-performance organophosphorus flame-retardant polyamide composite material.

[0018] Furthermore, in step S1, the mass ratio of the activated glass fiber to the silane coupling agent is (3-10):(2-10), and the mass ratio of the intermediate product to the double-bond terminated polyamide ester is (3-10):(15-50).

[0019] Furthermore, in step S1, the temperature of the blending heating reaction is 70-90°C, and the temperature of the blending heating stirring reaction is 50-90°C.

[0020] Furthermore, in step S2, the mass ratio of the titanium dioxide to trihydroxyethane is 100:(0.2-1).

[0021] Furthermore, in step S2, the stirring temperature is 30-40°C.

[0022] The present invention has the following beneficial effects:

[0023] The present invention prepares the modified glass fiber by reacting glass fiber, silane coupling agent and double-bond terminated polyamide ester with hyperbranched structure, introduces groups such as polyamide ester and aromatic group into the glass fiber, so that the compatibility with organic components is enhanced, especially the compatibility with the main component polyamide is significantly enhanced, and the glass fiber can be evenly dispersed, avoiding the adverse effect of glass fiber aggregation on product performance, and the introduced polyamide ester chain segment can also be entangled with other components to enhance the stability of the three-dimensional cross-linked structure and improve the mechanical properties of the product; the present invention also prepares the modified titanium dioxide by reacting titanium dioxide and trihydroxyethane, so that the titanium dioxide is grafted with organic groups containing a large number of hydroxyl groups, so that the titanium dioxide is prevented from agglomerating, so that the titanium dioxide and the laser marking auxiliary agent wrapped with the titanium dioxide can be evenly dispersed, and the bonding strength with other components can be improved through intermolecular forces, thereby improving various performances of the product. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 The product of Example 1 marked with a laser having a wavelength of 355 nm is shown.

[0025] Figure 2 The product of Example 2 marked with a laser of 355 nm wavelength is shown. DETAILED DESCRIPTION

[0026] In order to more clearly illustrate the technical solution of the present invention, the following examples are listed. Unless otherwise stated, the raw materials, reactions and post-treatment methods shown in the examples are common raw materials on the market and technical methods well known to those skilled in the art.

[0027] The words "preferred", "preferably", "more preferably", etc. in the present invention refer to embodiments of the present invention that can provide certain beneficial effects in certain circumstances. However, other embodiments may also be preferred under the same circumstances or other circumstances. In addition, the description of one or more preferred embodiments does not imply that other embodiments are not applicable, nor is it intended to exclude other embodiments from the scope of the present invention.

[0028] It should be understood that, except in any operating examples, or where otherwise indicated, all numbers indicating, for example, the amounts of ingredients used in the specification and claims should be understood to be modified in all cases by the term "about". Therefore, unless indicated to the contrary, the numerical parameters set forth in the following specification and the appended claims are approximate values ​​that vary depending on the desired properties to be obtained by the present invention.

[0029] The following raw materials are used in the embodiments of the present invention:

[0030] PA6, polyamide, molecular weight 15000-20000, purchased from Suzhou Putes Electronic Materials Co., Ltd.;

[0031] Glass fiber, diameter 9-20 μm, purchased from Boligen (Xiamen) Composite Materials Co., Ltd.;

[0032] Organic phosphorus flame retardant, a composite flame retardant of diethyl aluminum hypophosphite and melamine polyphosphate in a mass ratio of 2:1, purchased from Jiangsu Liside New Materials Co., Ltd.;

[0033] Titanium dioxide, particle size 100-200 nm, purchased from Dongguan Tuonuo Titanium Co., Ltd.;

[0034] The additives include lubricant zinc stearate and pigment in a mass ratio of 1:5, which are purchased from Shandong Shouhua Chemical Co., Ltd.

[0035] Dibenzoyl peroxide, initiator, was purchased from Guangzhou Yuanchuang Chemical Co., Ltd.

[0036] The preparation method of the laser marking auxiliary agent comprises the following steps:

[0037] M1. Dissolve 4 ml of tetraisopropyl titanate in 8 ml of glacial acetic acid, stir for 0.5 h, add 25 ml of distilled water and stir to obtain a hydrated titanium dioxide sol;

[0038] M2, add 25g zinc sulfide to 250ml distilled water, then add 20mg sodium dodecyl sulfate, ultrasonicate for 20min, adjust the pH value of the solution to 2.2 with 30wt% hydrochloric acid to obtain a suspension;

[0039] M3. At 30°C, slowly add hydrated titanium dioxide sol into the suspension and stir for 4 hours. After the reaction stops, separate, wash, dry at 100°C for 12 hours, and calcine at 500°C for 2 hours to obtain zinc sulfide with a titanium dioxide film coated on the surface, i.e., a laser marking aid.

[0040] The preparation method of double-bond terminated polyamide ester comprises the following steps:

[0041] L1, dissolve 8.646g of trimellitic anhydride in 40mL DMAc, dissolve 5.994g of diisopropanolamine in 40mL DMAc, then mix the two, stir and react at room temperature for 3h to obtain a polymerized monomer;

[0042] L2, add 30mL toluene, 0.746g triethanolamine, 0.054g p-toluenesulfonic acid to the polymerized monomer, heat to 130°C, condense and reflux for 24h, separate, reduce pressure, distill and purify to obtain a hydroxyl-terminated hyperbranched polymer;

[0043] L3. Add 40 ml of N,N-dimethylformamide and 5.165 g of methyl acrylate to the terminal hydroxyl hyperbranched polymer, then repeatedly evacuate and pass nitrogen to remove air, add 0.5% of the total mass of the reactants as an initiator sodium p-toluenesulfonate, keep the temperature at 80°C for 8 hours, then remove the solvent and vacuum dry to obtain a double-bond terminated polyamide ester.

[0044] The structure of the double bond terminated polyamide ester is:

[0045]

[0046] Wherein, m and n are both positive integers.

[0047] Example 1

[0048] A laser-markable, light-colored and colorful high-performance organic phosphorus flame-retardant polyamide composite material, comprising the following components in mass fractions:

[0049]

[0050]

[0051] The method for preparing the laser-markable, light-colored and colorful high-performance organic phosphorus flame-retardant polyamide composite material comprises the following steps:

[0052] S1. Heat the glass fiber to 500°C for 3 hours, then mix the glass fiber and 65wt% nitric acid in a mass ratio of 4:45, heat to 70°C for 5 hours, wash it with a mixed solution of deionized water and anhydrous ethanol (volume ratio of 1:1) until it is neutral and dry it, mix the dried glass fiber, deionized water and anhydrous ethanol in a mass ratio of 4:50:5, ultrasonicate for 30 minutes and dry it to obtain activated glass fiber, mix the activated glass fiber and KH-570 in a mass ratio of 4:3, Add glacial acetic acid dropwise to adjust the pH value to 5, perform ultrasonic treatment for 30 minutes, heat to 80°C and stir for 1 hour, centrifuge, wash and dry to obtain an intermediate product, blend the intermediate product, double-bond terminated polyamide ester and anhydrous ethanol in a mass ratio of 4:20:250, stir for 10 minutes, add dibenzoyl peroxide (the mass ratio of the intermediate product to dibenzoyl peroxide is 4:0.5), condense and reflux, heat to 50°C and stir for 30 minutes, heat to 85°C and react for 6 hours, centrifuge and dry to obtain a modified glass fiber;

[0053] S2, titanium dioxide, trihydroxyethane, and deionized water are mixed and stirred at a mass ratio of 100:0.5:250 at 40° C. for 30 min, dried at 120° C. for 24 h, and crushed to obtain modified titanium dioxide;

[0054] S3. According to the above mass fractions, the polyamide, the modified glass fiber, the organophosphorus flame retardant, the modified titanium dioxide, the laser marking aid and the additive are blended, added into a twin-screw extruder for melt extrusion granulation (feeding temperature 200°C, melting temperature 220°C, extrusion temperature 220°C) to obtain the laser-markable, light-colored and colorful high-performance organophosphorus flame-retardant polyamide composite material.

[0055] Figure 1 The product of Example 1 marked with a laser having a wavelength of 355 nm is shown.

[0056] from Figure 1 As you can see, the product is white, the logo is clear, and the color is black.

[0057] Example 2

[0058] A laser-markable, light-colored and colorful high-performance organic phosphorus flame-retardant polyamide composite material, comprising the following components in mass fractions:

[0059]

[0060] The method for preparing the laser-markable, light-colored and colorful high-performance organic phosphorus flame-retardant polyamide composite material comprises the following steps:

[0061] S1. Heat the glass fiber to 500°C for 3 hours, then mix the glass fiber and 65wt% nitric acid in a mass ratio of 4:45, heat to 75°C for 5 hours, wash it with a mixed solution of deionized water and anhydrous ethanol (volume ratio of 1:1) until it is neutral and dry it, mix the dried glass fiber, deionized water and anhydrous ethanol in a mass ratio of 4:50:5, ultrasonicate for 30 minutes and dry it to obtain activated glass fiber, mix the activated glass fiber and KH-570 in a mass ratio of 4:3, Add glacial acetic acid dropwise to adjust the pH value to 5, perform ultrasonic treatment for 30 minutes, heat to 80°C and stir for 1 hour, centrifuge, wash and dry to obtain an intermediate product, blend the intermediate product, double-bond terminated polyamide ester and anhydrous ethanol in a mass ratio of 4:20:250, stir for 10 minutes, add dibenzoyl peroxide (the mass ratio of the intermediate product to dibenzoyl peroxide is 4:0.5), condense and reflux, heat to 50°C and stir for 30 minutes, heat to 85°C and react for 6 hours, centrifuge and dry to obtain a modified glass fiber;

[0062] S2, titanium dioxide, trihydroxyethane, and deionized water are mixed and stirred at a mass ratio of 100:0.5:250 at 40° C. for 30 min, dried at 125° C. for 24 h, and crushed to obtain modified titanium dioxide;

[0063] S3. According to the above mass fractions, the polyamide, the modified glass fiber, the organophosphorus flame retardant, the modified titanium dioxide, the laser marking aid and the additive are blended, added into a twin-screw extruder for melt extrusion granulation (feeding temperature 200°C, melting temperature 220°C, extrusion temperature 220°C) to obtain the laser-markable, light-colored and colorful high-performance organophosphorus flame-retardant polyamide composite material.

[0064] Figure 2 The product of Example 2 marked with a laser of 355 nm wavelength is shown.

[0065] from Figure 2 As you can see, the product is orange, the logo is clear, and the color is white.

[0066] Example 3

[0067] A laser-markable, light-colored and colorful high-performance organic phosphorus flame-retardant polyamide composite material, comprising the following components in mass fractions:

[0068]

[0069] The method for preparing the laser-markable, light-colored and colorful high-performance organic phosphorus flame-retardant polyamide composite material comprises the following steps:

[0070] S1. Heat the glass fiber to 500°C for 3 hours, then mix the glass fiber and 65wt% nitric acid at a mass ratio of 4:45, heat to 70°C for 5 hours, wash it with a mixed solution of deionized water and anhydrous ethanol (volume ratio of 1:1) until it is neutral and dry it, mix the dried glass fiber, deionized water and anhydrous ethanol at a mass ratio of 4:50:5, ultrasonicate for 30 minutes and dry it to obtain activated glass fiber, mix the activated glass fiber and KH-570 at a mass ratio of 4:5, Add glacial acetic acid dropwise to adjust the pH value to 5, perform ultrasonic treatment for 30 minutes, heat to 80°C and stir for 1 hour, centrifuge, wash and dry to obtain an intermediate product, blend the intermediate product, double-bond terminated polyamide ester and anhydrous ethanol in a mass ratio of 4:20:250, stir for 10 minutes, add dibenzoyl peroxide (the mass ratio of the intermediate product to dibenzoyl peroxide is 4:0.5), condense and reflux, heat to 50°C and stir for 30 minutes, heat to 90°C and react for 6 hours, centrifuge and dry to obtain a modified glass fiber;

[0071] S2, titanium dioxide, trihydroxyethane, and deionized water are mixed and stirred at a mass ratio of 100:0.6:250 at 40° C. for 30 min, dried at 120° C. for 24 h, and crushed to obtain modified titanium dioxide;

[0072] S3. According to the above mass fractions, the polyamide, the modified glass fiber, the organophosphorus flame retardant, the modified titanium dioxide, the laser marking aid and the additive are blended, added into a twin-screw extruder for melt extrusion granulation (feeding temperature 200°C, melting temperature 220°C, extrusion temperature 220°C) to obtain the laser-markable, light-colored and colorful high-performance organophosphorus flame-retardant polyamide composite material.

[0073] Comparative Example 1

[0074] The difference between Comparative Example 1 and Example 1 is that the modified glass fiber is replaced by the intermediate product, and the other preparation methods and components are the same as those of Example 1.

[0075] Comparative Example 2

[0076] The difference between Comparative Example 2 and Example 1 is that the modified titanium dioxide is replaced by titanium dioxide treated with KH560, and S2 is modified into the following steps:

[0077] S2, titanium dioxide and 95wt% ethanol were blended in a mass ratio of 5:95, ultrasonicated for 30 min, KH560 was added (the mass ratio of titanium dioxide and KH560 was 100:1), the pH was adjusted to neutral, stirred evenly, heated to 80°C for reaction for 2 h, and titanium dioxide treated with KH560 was obtained;

[0078] The other preparation methods and ingredients are the same as those in Example 1.

[0079] Test Example 1

[0080] The mechanical properties, flame retardant properties and laser marking effects of Examples 1-3 and Comparative Examples 1-2 were tested.

[0081] Test Method

[0082] The mechanical properties and flame retardant properties are tested according to ISO 527, ISO 178, ISO 180 and UL-94.

[0083] Table 1 shows the results of the tests.

[0084] Table 1 Test results and laser marking effects of Examples 1-3 and Comparative Examples 1-2

[0085]

[0086]

[0087] It can be seen from Table 1 that the various properties of Examples 1-3 are better than those of Comparative Examples 1-2.

[0088] The various properties of Examples 1-3 are better than those of Comparative Example 1 because in Comparative Example 1, the modified glass fiber is replaced by glass fiber without polyamide ester, which reduces the compatibility and synergistic effect between the components, making it difficult to evenly disperse the glass fiber and significantly reducing the material strength.

[0089] The various properties of Examples 1-3 are better than those of Comparative Example 2 because in Comparative Example 2, the modified titanium dioxide is replaced with titanium dioxide treated with KH560, which reduces the compatibility of titanium dioxide, laser marking additives and other components, makes them easily agglomerated, and reduces the performance.

[0090] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be considered exemplary and non-restrictive in all respects, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention.

[0091] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A laser-markable, light-colored and colorful high-performance organic phosphorus flame-retardant polyamide composite material, characterized in that: The laser-markable, light-colored and colorful high-performance organic phosphorus flame-retardant polyamide composite material comprises the following components in mass fraction: Wherein, the modified glass fiber is obtained by reacting glass fiber, silane coupling agent and double-bond terminated polyamide ester; The modified titanium dioxide is obtained by reacting titanium dioxide and trihydroxyethane.

2. The laser-markable, light-colored and colorful high-performance organic phosphorus flame-retardant polyamide composite material according to claim 1, characterized in that: The silane coupling agent is a silane coupling agent containing a double bond.

3. The laser-markable, light-colored and colorful high-performance organic phosphorus flame-retardant polyamide composite material according to claim 1, characterized in that: The organic phosphorus flame retardant is a diethyl aluminum hypophosphite composite flame retardant.

4. The laser-markable, light-colored and colorful high-performance organic phosphorus flame-retardant polyamide composite material according to claim 1, characterized in that: The auxiliary agent is selected from one or more of lubricants, antioxidants, weathering agents, and pigments.

5. The laser-markable, light-colored and colorful high-performance organic phosphorus flame-retardant polyamide composite material according to claim 1, characterized in that: The laser marking auxiliary agent is titanium dioxide coated zinc sulfide.

6. The method for preparing the laser-markable, light-colored and colorful high-performance organic phosphorus flame-retardant polyamide composite material according to any one of claims 1 to 5, characterized in that: The method for preparing the laser-markable, light-colored and colorful high-performance organic phosphorus flame-retardant polyamide composite material comprises the following steps: S1, mixing glass fiber and nitric acid and heating to obtain activated glass fiber, then mixing with a silane coupling agent and heating to react to obtain an intermediate product, and finally mixing with a double-bond terminated polyamide ester and an initiator and heating and stirring to react to obtain a modified glass fiber; S2, mixing titanium dioxide and trihydroxyethane, and drying to obtain modified titanium dioxide; S3, blending polyamide, the modified glass fiber, the organophosphorus flame retardant, the modified titanium dioxide, the laser marking aid, and the additive, adding them into a twin-screw extruder, and melt-extruding and granulating them at 200-280°C to obtain the laser-markable, light-colored and colorful high-performance organophosphorus flame-retardant polyamide composite material.

7. The method for preparing the laser-markable, light-colored and colorful high-performance organic phosphorus flame-retardant polyamide composite material according to claim 6, characterized in that: In step S1, the mass ratio of activated glass fiber to silane coupling agent is (3-10):(2-10), and the mass ratio of intermediate product to double-bond terminated polyamide ester is (3-10):(15-50).

8. The method for preparing the laser-markable, light-colored and colorful high-performance organic phosphorus flame-retardant polyamide composite material according to claim 6, characterized in that: In step S1, the temperature of the blending heating reaction is 70-90°C, and the temperature of the blending heating stirring reaction is 50-90°C.

9. The method for preparing the laser-markable, light-colored and colorful high-performance organic phosphorus flame-retardant polyamide composite material according to claim 6, characterized in that: In step S2, the mass ratio of the titanium dioxide to trihydroxyethane is 100:(0.2-1).

10. The method for preparing the laser-markable, light-colored and colorful high-performance organic phosphorus flame-retardant polyamide composite material according to claim 6, characterized in that: In step S2, the stirring temperature is 30-40°C.

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