Organic phosphine flame-retardant nylon composition as well as preparation method and application thereof

Abstract

The invention discloses an organic phosphine flame-retardant nylon composition as well as a preparation method and application thereof, and the organic phosphine flame-retardant nylon composition comprises the following components in parts by weight: 25-62 parts of homopolymerized nylon resin, 5-10 parts of copolymerized nylon resin, 5-15 parts of barrier nylon resin, 20-30 parts of glass fiber, 8-12 parts of an organic phosphine flame retardant and 1-4 parts of a flame-retardant synergist. And 1-3 parts of an interface bonding agent. The organic phosphine flame-retardant nylon composition disclosed by the invention has excellent silica gel adhesive property and also has high mechanical property and flame-retardant property.

Description

Technical Field

[0001] The invention relates to the technical field of polymer materials, and in particular to an organic phosphine flame-retardant nylon composition and a preparation method and application thereof. Background Art

[0002] Organophosphine flame-retardant nylon has excellent flame retardant properties, mechanical properties, electrical properties, low smoke and halogen-free, and environmental protection, and is widely used in electronic appliances, new energy, rail transportation and other fields. Silicone rubber has attracted much attention in terms of sealing, insulation and protection due to its excellent high and low temperature resistance, electrical insulation and flexibility. Bonding organophosphine flame-retardant nylon with silicone rubber can achieve complementary and synergistic performance enhancement, such as solving the airtightness problem of new energy connectors and the connection problem of split liquid cooling pipes, bringing more innovation and convenience to product design and manufacturing.

[0003] Polyamide molecules have large polarity, while silicone rubber molecules have small polarity, so it is difficult for silicone rubber to form effective physical or chemical adhesion with the surface of nylon. In the prior art, the adhesion between silicone rubber and polyamide substrates is often improved by plasma treatment and the application of primers. The primers can form chemical bonds with silicone and polyamide surfaces at the same time, thereby achieving the purpose of silicone bonding polyamide. However, the inventors found that when using primers, the bonding strength between conventional organophosphine flame-retardant nylon compositions and silicone will decrease over time. Further research found that the organophosphine flame retardant in the system will gradually migrate to the surface over time, thereby causing the silicone rubber and nylon to be placed for a long time. The adhesion is reduced, which makes the production efficiency low, and pollutes the environment, so that the scope of application of this solution is greatly limited. Therefore, it is urgent to develop an organophosphine flame-retardant nylon composition with excellent silicone rubber bonding performance and excellent mechanical properties to improve production efficiency while avoiding the problem of environmental pollution caused by the use of primers. Summary of the invention

[0004] In view of the defects in the prior art, the present invention provides an organic phosphine flame retardant nylon composition and a preparation method and application thereof.

[0005] The present invention provides an organic phosphine flame retardant nylon composition, which comprises the following components by weight: 25-62 parts of homopolymerized nylon resin, such as 25, 26, 30, 35, 40, 45, 50, 55, 60, 62 parts; 5-10 parts of copolymerized nylon resin, such as 5, 6, 7, 8, 9, 10 parts; 5-15 parts of barrier nylon resin, such as 5, 8, 10, 12, 15 parts; 20-30 parts of glass fiber, such as 20, 22, 24, 25 parts; 6, 28, 30 parts; 8-12 parts of organic phosphine flame retardant, such as 8, 9, 10, 11, 12 parts; 1-4 parts of flame retardant synergist, such as 1, 2, 3, 4 parts; 1-3 parts of interface binder, such as 1, 2, 3 parts; the interface binder is a compound of one or more of siloxane containing amino functional groups or siloxane containing epoxy functional groups, and the flame retardant synergist is polyvinyl pyrrolidone with a molecular weight of 1000-60000g / mol;

[0006] In the design formula of the present invention, the addition of barrier nylon can reduce the migration of organic phosphine flame retardant to the surface and improve the bonding performance of nylon and silicone. On the other hand, since it contains a benzene ring structure, it can promote the carbonization effect, thereby improving its flame retardant performance; copolymerized nylon is beneficial to improving the injection molding appearance, reducing floating fibers, and can improve the bonding performance of silicone rubber; a specific flame retardant synergist polyvinyl pyrrolidone can be combined with the organic phosphine flame retardant to promote the dispersion of the organic phosphine flame retardant and inhibit its migration to the surface, which can be beneficial to the improvement of the bonding performance of silicone while synergistically flame retardant; in a specific interface binder, the amino and epoxy groups can react with the end groups of nylon, and the alkoxy group can react with the flame retardant or silicone rubber, thereby improving the bonding strength of the composition with silicone.

[0007] Furthermore, the homonylon resin is an aliphatic homonylon resin, preferably one or more of PA66, PA6, PA56, PA612 or PA610.

[0008] Furthermore, the copolymerized nylon resin contains hexamethylenediamine adipate segments, preferably one or more of PA66 / 6, PA6 / 66 or PA66 / 6T.

[0009] Furthermore, the barrier nylon resin is one or more of PA MXD6, PA6I / 6T or PA MXD10.

[0010] Furthermore, the organic phosphine flame retardant is one or more of aluminum hypophosphite, diethyl aluminum hypophosphite, and diisopropyl aluminum hypophosphite, preferably diethyl aluminum hypophosphite.

[0011] Furthermore, the glass fiber is any one of E glass fiber, H glass fiber, S glass fiber, D glass fiber or C glass fiber, preferably E glass fiber.

[0012] Furthermore, the interface binder is any one of aminomethoxysilane, aminoethoxysilane, epoxymethoxysilane and epoxyethoxysilane.

[0013] Furthermore, the siloxane containing amino functional groups includes but is not limited to any one of 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, and N-n-butyl-3-aminopropyltrimethoxysilane, and the siloxane containing epoxy functional groups includes but is not limited to any one of γ-(2,3-epoxypropyloxy)propyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, and 3-(2,3-epoxypropyloxy)propylmethyldiethoxysilane.

[0014] The present invention also provides a method for preparing the nylon composition, comprising the following steps:

[0015] Weighing each component by weight, putting each component into a mixer to mix until uniform, to obtain a premix, and then putting the obtained premix into a twin-screw extruder for melt mixing, and extruding and granulating to obtain the nylon composition;

[0016] The twin-screw extruder has a screw speed of 250-350 rpm, an aspect ratio of (40-48):1, and a barrel temperature of 200-290°C.

[0017] The present invention also provides application of the nylon composition in new energy batteries, connectors and electric tools.

[0018] In summary, compared with the prior art, the present invention achieves the following technical effects:

[0019] (1) The organic phosphorus flame-retardant nylon composition provided by the present invention has high bonding strength with silicone rubber;

[0020] (2) The organophosphorus flame-retardant nylon composition provided by the present invention can maintain high mechanical properties while improving the bonding strength with silicone rubber;

[0021] (3) The organophosphorus flame-retardant nylon composition provided by the present invention also has excellent flame retardant properties. DETAILED DESCRIPTION

[0022] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only embodiments of a part of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0023] Example

[0024] The present invention is further described below in conjunction with specific examples and comparative examples. The following specific examples are all preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the following examples, and are particularly not limited to the types of the various component raw materials used in the following specific examples.

[0025] 1. The sources of raw materials for the embodiments and comparative examples are as follows:

[0026] Homopolymer nylon resin #1: PA66, grade PA66EP-158, Huafeng Group;

[0027] Homopolymer nylon resin #2: PA6, brand PA6HY-2800, Haiyang Chemical Fiber Company;

[0028] Homopolymer nylon resin #3: PA612, brand PA612A120, Shandong Guangyin New Materials Co., Ltd.;

[0029] Copolymer nylon resin #1: PA66 / 6, grade B50H1, Solvay;

[0030] Copolymer nylon resin #2: PA66 / 6T, brand NPD-652, INVISTA Co., Ltd.

[0031] Barrier nylon resin #1: PA MXD6, grade MXD6AP 250, Shanghai Yinggu Co., Ltd.;

[0032] Barrier nylon resin #2: PA6I / 6T, brand TI1207, Shandong Guangyin New Materials Co., Ltd.;

[0033] Glass fiber: E glass fiber, grade ECS10-3.0-568H, China Jushi Co., Ltd.

[0034] Organic phosphine flame retardant: diethyl aluminum hypophosphite, brand OP1230, Klein Co., Ltd.;

[0035] Flame retardant synergist #1: polyvinyl pyrrolidone, brand PVP K90, Shanghai Kema New Materials Co., Ltd.;

[0036] Flame retardant synergist #2: melamine polyphosphate, brand BUDIT 3141, Budenheim Iberica, Germany;

[0037] Interface binder #1: 3-aminopropyltriethoxysilane, brand KH550, Chenguang New Materials;

[0038] Interface binder #2: N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane coupling agent, brand CG-602, Chenguang New Materials;

[0039] Interface binder #3: 3-(2,3-epoxypropoxy)propyltrimethoxysilane coupling agent, brand KH560, Chenguang New Materials;

[0040] Interface binder #4: 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane coupling agent, brand CG-O186, Chenguang Chemical;

[0041] Interface binder #5: methyltriethoxysilane coupling agent, brand CG-106, Chenguang New Materials.

[0042] The preparation method of the nylon composition of the embodiment and the comparative example of the present invention comprises the following steps:

[0043] Weighing each component by weight, putting each component into a mixer to mix until uniform, to obtain a premix, and then putting the obtained premix into a twin-screw extruder for melt mixing, and extruding and granulating to obtain the nylon composition;

[0044] The twin-screw extruder has a screw speed of 250-350 rpm, an aspect ratio of (40-48):1, and a barrel temperature of 200-290°C.

[0045] 2. Various performance test methods

[0046] (1) Flame retardant performance: The flame retardant performance of the sample strip is tested according to the relevant standards of UL 94-2015. The sample thickness is 0.8 mm. The flame retardant grades are divided into V-0, V-1, V-2 and no grade (NR). Flame retardant performance is of great significance to electrical safety. The UL94 flame retardant grade needs to reach V-0 to meet application requirements;

[0047] (2) Tensile strength: tested in accordance with ISO 527-2012;

[0048] (3) Izod notched impact strength: tested in accordance with ISO 180-2000;

[0049] (4) Adhesion performance test: The nylon strips (150*25*2mm) were first cleaned with ethanol and then treated with low-temperature plasma for 10 min. Two treated strips were overlapped with a length of 20 mm and coated with addition-type liquid silicone rubber. They were bonded together in a butt-jointed manner and pressurized with a 2000 g weight. The strips were placed at 120°C for 20 min. After being taken out and cooled, the bonding strength was measured using a tensile testing machine.

[0050] Table 1 Technical solutions and effects of the embodiments (unit: weight parts)

[0051]

[0052] Table 2 Comparative Examples Technical Scheme and Effects (Units are parts by weight)

[0053]

[0054] In Examples 1-9, homopolymerized nylon resin, copolymerized nylon resin, barrier nylon resin, organic phosphate, glass fiber, specific flame retardant synergist and specific interfacial binder are introduced at the same time. Through the dual effects of barrier nylon and polyvinyl pyrrolidone, firstly, the migration of flame retardant to the surface can be inhibited, thereby improving the bonding strength of organic phosphine flame retardant nylon silicone rubber. Secondly, both can promote the carbonization of nylon, thereby improving its flame retardant properties. The property that the molecular chain of the amorphous region of copolymerized nylon is easily activated is utilized to improve the bonding performance with silicone rubber. The organic phosphine flame retardant nylon composition prepared in Examples 1-9 has excellent flame retardant properties, mechanical properties and silicone bonding properties, wherein the tensile strength reaches 122MPa or above, and the cantilever beam notched impact strength reaches 10.8kJ / m 2 And above, the silicone bonding strength reaches above 3.0MPa.

[0055] It can be seen from Example 3 and Comparative Example 1 that the conventional organic phosphine flame retardant nylon silicone has poor bonding performance; it can be seen from Example 3 and Comparative Example 2 that without introducing barrier nylon, the flame retardant performance and bonding strength of the organic phosphine flame retardant nylon composition are significantly reduced; it can be seen from Example 3 and Comparative Example 3 that without introducing copolymerized nylon, the bonding strength of the organic phosphine flame retardant nylon composition is reduced; it can be seen from the comparison between Example 3, Comparative Example 4, Comparative Example 7 and Comparative Example 10 that without introducing polyvinyl pyrrolidone or introducing other flame retardant synergists, the flame retardant performance and bonding strength of the organic phosphine flame retardant nylon composition are significantly reduced, but excessive addition of polyvinyl pyrrolidone will combine with the nylon molecular chain in the amorphous region, which will not only deteriorate the mechanical properties of the material, but also reduce its silicone bonding strength; it can be seen from Example 3, Comparative Example 5 and Comparative Example 8 that without introducing specific siloxane containing amino functional groups and / or containing epoxy functional groups, the flame retardant performance and bonding strength of the organic phosphine flame retardant nylon composition are significantly reduced. The mechanical properties and bonding strength of the organic phosphine flame retardant nylon composition are significantly reduced. This is because the specific interface binder can not only improve the interface effect between the flame retardant and nylon, improve its mechanical properties, but also improve the interface bonding force between nylon and silicone rubber, thereby improving the bonding strength. However, if the amount of aminosiloxane added is too high, the thermal stability of the material will deteriorate, and it is easy to hydrolyze and crosslink, thereby causing its mechanical properties, flame retardant properties and bonding properties to decrease; it can be seen from Example 3 and Comparative Example 6 that when the content of the organic phosphine flame retardant is too high, it is easy to migrate to the surface, thereby causing the bonding strength of the silicone rubber to decrease; it can be seen from Example 3, Example 5 and Comparative Example 9 that siloxanes with amino or epoxy groups can improve the flame retardant properties and bonding strength of the organic phosphine nylon composition, and only siloxanes with amino or epoxy groups can play a good bridging role. None of the above comparative examples can achieve good flame retardant properties, mechanical properties, and the bonding strength of the composition and silicone at the same time.

[0056] Based on the test data of vertical burning performance, tensile strength, cantilever beam notched impact strength and bonding strength in Tables 1 and 2, the organophosphorus flame-retardant nylon composition prepared by Examples 1-9 has obvious advantages over the comparative example and can effectively meet the high standards of customers and the market.

[0057] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. An organic phosphine flame-retardant nylon composition, characterized in that: By weight, it includes the following components: The interface binder is a combination of one or more of siloxane containing amino functional groups or siloxane containing epoxy functional groups, and the flame retardant synergist is polyvinyl pyrrolidone.

2. The nylon composition according to claim 1, characterized in that The homopolymer nylon resin is one or more of PA66, PA6, PA56, PA612 or PA610.

3. The nylon composition according to claim 1, characterized in that The copolymer nylon resin is one or more of PA66 / 6, PA6 / 66 or PA66 / 6T.

4. The nylon composition according to claim 1, characterized in that The barrier nylon resin is one or more of PA MXD6, PA6I / 6T or PA MXD10.

5. The nylon composition according to claim 1, characterized in that The organic phosphine flame retardant is one or more of aluminum hypophosphite, diethyl aluminum hypophosphite, and diisopropyl aluminum hypophosphite.

6. The nylon composition according to claim 1, characterized in that The glass fiber is any one of E glass fiber, H glass fiber, S glass fiber, D glass fiber or C glass fiber.

7. The nylon composition according to claim 1, characterized in that The interface binder is any one of aminomethoxysilane, aminoethoxysilane, epoxymethoxysilane or epoxyethoxysilane.

8. The method for preparing the nylon composition according to any one of claims 1 to 7, characterized in that: The steps include: The components are weighed in parts by weight, and the components are put into a mixer to be mixed until uniform to obtain a premix, and then the obtained premix is ​​put into a twin-screw extruder for melt mixing, and extrusion granulation is performed to obtain the nylon composition.

9. Use of the nylon composition according to any one of claims 1 to 7 in new energy batteries, connectors and electric tools.

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