Halogen-free and phosphorus-free flame-retardant nylon material and preparation method thereof

Abstract

The present invention discloses a halogen-free and phosphorus-free flame-retardant nylon material and a preparation method thereof. The halogen-free and phosphorus-free flame-retardant nylon material is compounded with ultra-low melting point glass fiber (LMG fiber) and low melting point glass powder. When the material burns, it melts on the surface to form an isolation layer, isolating the internal combustibles from contacting with external oxygen, isolating the flame, and preventing combustion. The flame retardant synergist releases crystal water, which plays a synergistic flame retardant role of diluting the concentration of combustibles and oxygen at the initial stage of fire. The halogen-free and phosphorus-free flame-retardant nylon material is truly halogen-free and phosphorus-free flame-retardant nylon material by compounding ultra-low melting point glass fiber (LMG fiber) and low melting point glass powder and a synergistic flame retardant, with a flame retardant of 1.6mmV0 and a glow wire that does not burn at 750°C.

Description

Technical Field

[0001] The invention belongs to the field of flame-retardant nylon materials, and particularly relates to a halogen-free and phosphorus-free flame-retardant nylon material and a preparation method thereof. The nylon material does not contain halogen and phosphorus-based materials, and effectively avoids the environmental pollution problem in the prior art. Background Art

[0002] Flame-retardant nylon, as an engineering plastic, is widely used in electronics, automobiles, construction and other fields. However, traditional flame-retardant nylon usually contains halogens and phosphorus elements, which will produce toxic and harmful gases during combustion, affecting the environment and human health. Some European and American countries restrict the use of halogen-containing and phosphorus-containing flame retardants. Therefore, the development of a halogen-free and phosphorus-free flame-retardant nylon material is an important technical demand at present.

[0003] In the prior art, Chinese patent CN101531811A "A nylon 66 halogen-free and phosphorus-free flame-retardant thermoplastic engineering plastic" discloses a method for preparing a halogen-free and phosphorus-free flame-retardant nylon material, but the melamine phosphate in the flame retardant contains phosphorus; the halogen-free and phosphorus-free flame retardant polythiophenylphosphonic acid (9,10-dihydro-9-oxa-10-phosphonophenanthrene) phenylene ester (PDPTP) used in the preparation method disclosed in Chinese patent CN101798447A "PBT special halogen-free and phosphorus-free flame retardant toughening masterbatch and preparation method thereof" also contains phosphorus; Chinese patent CN110054888A "A flame-retardant bio-based PA56 composite material and preparation method thereof" discloses a preparation method using melamine pyrophosphate, and the flame retardant also contains phosphorus. None of these prior arts are truly halogen-free and phosphorus-free.

[0004] Therefore, the development of a truly halogen-free and phosphorus-free flame-retardant nylon remains an urgent need. Summary of the invention

[0005] In view of the above problems existing in the prior art, according to a first aspect of the present invention, an object of the present invention is to provide a halogen-free and phosphorus-free flame-retardant nylon material.

[0006] According to the second aspect of the present invention, the second object of the present invention is to provide a method for preparing the halogen-free and phosphorus-free flame-retardant nylon material.

[0007] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0008] A halogen-free and phosphorus-free flame-retardant nylon material, composed of the following raw materials by weight percentage:

[0009]

[0010] Preferably, the nylon resin is a compound of commercially available PA6 chips and commercially available PA66 chips, or one of them.

[0011] Preferably, the halogen-free and phosphorus-free flame retardant is compounded from components A and B, wherein component A is ultra-low melting point glass fiber (LMG fiber) with a characteristic glass transition temperature of 110-200°C and a softening melting temperature of 340-500°C; component B is low melting point glass powder with a characteristic glass transition temperature of 110-200°C and a softening melting temperature of 340-500°C.

[0012] Preferably, the flame retardant synergist is one or more of nano zinc oxide, zinc borate, and hydrotalcite.

[0013] Preferably, the antioxidant is a combination of a hindered phenol primary antioxidant and a phosphite auxiliary antioxidant in a ratio of 1:2.

[0014] Preferably, the lubricating dispersant is a compound of one or more of spirocyclic (CBT) resin, ethylene bisstearamide (EBS), silicone, calcium stearate, and ethylene bisstearamide modified BAB type copolymer (TAF).

[0015] Preferably, the other additives include one or more of a compatibilizer, a nucleating agent, a masterbatch, and a weathering agent. Preferably, the halogen-free and phosphorus-free flame-retardant nylon material may not include the other additives, that is, the content of the other additives may be zero.

[0016] A method for preparing a halogen-free and phosphorus-free flame-retardant nylon material comprises the following steps:

[0017] (1) Mix the halogen-free and phosphorus-free flame retardant component B, flame retardant synergist, antioxidant, lubricating dispersant and other additives in proportion for 1-5 minutes, then add nylon resin in proportion and mix for 1-5 minutes.

[0018] (2) The mixed material is added to the twin-screw extruder at the main feeding port, and the halogen-free and phosphorus-free flame retardant component A is added to the twin-screw extruder at the glass fiber port. The mixture is extruded, stretched, blown dry, and pelletized in a twin-screw extruder with a length-to-diameter ratio of 36:1-44:1. The extrusion speed is 300-500r / min, and the extrusion temperature is 220-270°C.

[0019] Beneficial Effects

[0020] 1. The present invention uses ultra-low melting point glass fiber (LMG fiber) and low melting point glass powder to form an isolation layer on the surface when the material burns, isolating the internal combustibles from contacting with external oxygen, isolating the flame and preventing combustion.

[0021] 2. The flame retardant synergist in the present invention releases crystal water, which plays a synergistic flame retardant role in diluting the concentration of combustibles and oxygen in the early stage of fire.

[0022] 3. The present invention realizes the halogen-free and phosphorus-free flame-retardant nylon material by using ultra-low melting point glass fiber (LMG fiber) and low melting point glass powder compound and synergistic flame retardant, with a flame retardant of 1.6mmV0 and a glow wire that does not burn at 750°C. DETAILED DESCRIPTION

[0023] Hereinafter, the present invention will be described in detail. Before describing, it should be understood that the terms used in this specification and the appended claims should not be interpreted as being limited to the general meaning and dictionary meaning, but should be interpreted according to the meaning and concept corresponding to the technical aspects of the present invention on the basis of the principle that the inventor is allowed to appropriately define the terms for the best interpretation. Therefore, the descriptions presented here are only preferred examples for illustrative purposes and are not intended to limit the scope of the present invention, so that it should be understood that other equivalents or improvements can be obtained therefrom without departing from the spirit and scope of the present invention.

[0024] The following examples are only listed as examples of embodiments of the present invention and do not constitute any limitation to the present invention. It can be understood by those skilled in the art that modifications within the scope of the essence and concept of the present invention fall within the scope of protection of the present invention. Unless otherwise specified, the reagents and instruments used in the following examples are commercially available products.

[0025] In this document, the terms "include", "including", "have", "contain" or any other similar terms are open conjunctions, which are intended to cover non-exclusive inclusions. For example, a composition or product containing multiple elements is not limited to the elements listed herein, but may also include other elements that are not explicitly listed but are generally inherent to the composition or product. In addition, unless otherwise explicitly stated, the term "or" refers to an inclusive "or" rather than an exclusive "or". For example, any of the following situations satisfies the condition "A or B": A is true (or exists) and B is false (or does not exist), A is false (or does not exist) and B is true (or exists), and A and B are both true (or exist). In addition, in this document, the interpretation of the terms "include", "including", "have", and "contain" should be considered to have been specifically disclosed and simultaneously cover closed or semi-closed conjunctions such as "consisting of" and "consisting essentially of".

[0026] In this article, all features or conditions defined in the form of numerical ranges or percentage ranges are only for brevity and convenience. Accordingly, the description of numerical ranges or percentage ranges should be deemed to have covered and specifically disclosed all possible secondary ranges and individual values ​​within the range, especially integer values. For example, the range description of "1 to 8" should be deemed to have specifically disclosed all secondary ranges such as 1 to 7, 2 to 8, 2 to 6, 3 to 6, 4 to 8, 3 to 8, etc., especially secondary ranges defined by all integer values, and should be deemed to have specifically disclosed individual values ​​such as 1, 2, 3, 4, 5, 6, 7, 8, etc. within the range. Unless otherwise specified, the above interpretation method applies to all contents of the entire present invention, regardless of whether the range is broad or not.

[0027] If the quantity or other numerical value or parameter is expressed as a range, a preferred range or a series of upper and lower limits, it should be understood that all ranges consisting of any upper limit or preferred value of the range and the lower limit or preferred value of the range have been specifically disclosed herein, regardless of whether these ranges are disclosed separately. In addition, if a numerical range is mentioned herein, unless otherwise specified, the range should include its endpoints and all integers and fractions within the range.

[0028] In this document, under the premise of achieving the purpose of the invention, numerical values ​​should be understood to have the accuracy of the number of significant digits of the numerical value. For example, the number 40.0 should be understood to cover the range from 39.50 to 40.49.

[0029] The present invention is further explained below with reference to specific embodiments, which are merely illustrative and exemplary and are not restrictive.

[0030] Example 1

[0031] According to the ingredients in parts by weight in Table 1 below, a halogen-free and phosphorus-free flame-retardant nylon material was prepared according to the following method.

[0032] (1) Mix the halogen-free and phosphorus-free flame retardant component B, flame retardant synergist, antioxidant, lubricating dispersant and other additives in proportion for 3 minutes, then add nylon resin in proportion and mix for 3 minutes.

[0033] (2) The mixed material is added to the twin-screw extruder at the main feeding port, and the halogen-free and phosphorus-free flame retardant component A is added to the twin-screw extruder at the glass fiber port. The mixture is extruded, stretched, blown dry, and pelletized in a twin-screw extruder with a length-to-diameter ratio of 40:1. The extrusion speed is 420 r / min and the extrusion temperature is 210-230°C.

[0034] Example 2

[0035] A halogen-free and phosphorus-free flame-retardant nylon material was prepared according to the ingredients in parts by weight in the following Table 1 and the same method as in Example 1, wherein the extrusion temperature of the twin-screw extruder was 240-260°C.

[0036] Example 3

[0037] A halogen-free and phosphorus-free flame-retardant nylon material was prepared according to the ingredients in parts by weight in the following Table 1 and the same method as in Example 1, wherein the extrusion temperature of the twin-screw extruder was 240-260°C.

[0038] Comparative Example 1

[0039] Halogen-containing phosphorus-free flame-retardant nylon material and halogen-free phosphorus-containing flame-retardant nylon material were prepared according to the same method as Example 1, wherein the extrusion temperature of the twin-screw extruder was 210-230°C.

[0040] Comparative Example 2

[0041] According to the weight amounts of the ingredients in Table 1 below, and in the same manner as in Example 1, a halogen-containing phosphorus-free flame-retardant nylon material and a halogen-free phosphorus-containing flame-retardant nylon material were prepared, wherein the extrusion temperature of the twin-screw extruder was 240-260°C.

[0042] Table 1

[0043]

[0044] The raw materials in the examples and comparative examples can all be obtained commercially.

[0045]

[0046]

[0047] Unless otherwise specified, the reagents, methods and equipment used in the present invention are conventional reagents, methods and equipment in the present technical field.

[0048] The detection method is as follows:

[0049] Density: GB / T 1033.1-2008.

[0050] Glow wire: GB / T 5169.13-2013, test GWIT775 / 2.0.

[0051] Burning: UL-94-2016, vertical burning, strip thickness 1.6mm.

[0052] The test results are shown in Table 2:

[0053] Table 2

[0054] Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 density 1.33 1.34 1.42 1.42 1.33 GWIT775 / 2.0 PASS PASS PASS PASS PASS UL94 1.6mm V0 V0 V0 V0 V0

[0055] It can be seen from the above table that the flame retardant nylon material with a flame retardancy of 1.6 mmV0 and a glow wire of 750°C that does not burn can be successfully prepared by compounding ultra-low melting point glass fiber, low melting point glass powder and flame retardant synergist (hydrotalcite or zinc borate). The above test results show that the flame retardant nylon material prepared by the method of the present invention is truly halogen-free and phosphorus-free compared with the comparative example under the condition of equivalent performance.

[0056] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A halogen-free and phosphorus-free flame-retardant nylon material, which is composed of the following raw materials by weight percentage: Nylon resin 50-93% Halogen-free and phosphorus-free flame retardant 5-35% Flame retardant synergist 1-5% Antioxidant 0.5-1% Lubricating dispersant 0.5-2% Other additives 0-7%; The halogen-free and phosphorus-free flame retardant is compounded by components A and B, wherein component A is ultra-low melting point glass fiber, the characteristic glass transition temperature is 110-200°C, and the softening melting temperature is 340-500°C; component B is low melting point glass powder, the characteristic glass transition temperature is 110-200°C, and the softening melting temperature is 340-500°C; The flame retardant synergist is one or more of nano zinc oxide, zinc borate and hydrotalcite.

2. The halogen-free and phosphorus-free flame-retardant nylon material according to claim 1, characterized in that: The nylon resin is a compound of commercially available PA6 chips and commercially available PA66 chips, or one of them.

3. The halogen-free and phosphorus-free flame-retardant nylon material according to claim 1, characterized in that: The antioxidant is a compound of a hindered phenol main antioxidant and a phosphite auxiliary antioxidant, with a weight ratio of 1:

2.

4. The halogen-free and phosphorus-free flame-retardant nylon material according to claim 1, characterized in that: The lubricating dispersant is a compound of one or more of spirocyclic resin, ethylene bisstearamide, silicone, calcium stearate, and ethylene bisstearamide modified BAB type copolymer.

5. The halogen-free and phosphorus-free flame-retardant nylon material according to claim 1, characterized in that: The other additives include one or more of a compatibilizer, a nucleating agent, a masterbatch, and a weathering agent, or the halogen-free and phosphorus-free flame-retardant nylon material does not include the other additives, that is, the content of the other additives is 0.

6. The method for preparing the halogen-free and phosphorus-free flame-retardant nylon material according to any one of claims 1 to 5, comprising the following steps: (1) Mix the halogen-free and phosphorus-free flame retardant component B, flame retardant synergist, antioxidant, lubricating dispersant and other additives in proportion for 1-5 minutes, then add nylon resin in proportion and mix for 1-5 minutes; (2) The mixed material is added to the twin-screw extruder at the main feeding port, and the halogen-free and phosphorus-free flame retardant component A is added to the twin-screw extruder at the glass fiber port. The mixed material is extruded, stretched, blown dry, and pelletized in a twin-screw extruder with a length-to-diameter ratio of 36:1-44:

1. The extrusion speed is 300-500r / min and the extrusion temperature is 220-270°C.

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