A nylon alloy material with metal bonding properties

Abstract

The present invention relates to the technical field of composite materials, and in particular to a PA12 alloy material with metal adhesion and a preparation method thereof. The PA12 alloy material with metal adhesion is prepared by adding an adhesive to a PA12 material, wherein the adhesive is a polymer prepared from bisphenol A and an epoxy resin, wherein the bisphenol A is one of n-methylhydroquinone (NMHQ), t-butylhydroquinone (TBHQ), and diallyl bisphenol A (DABPA), and the epoxy resin is one or a combination of epoxy equivalents of 150 to 200. The PA12 alloy material provided by the present invention uses an adhesive to react a nylon substrate with a metal adhesive, thereby significantly improving the metal bonding performance of the material.

Description

Technical Field

[0001] The invention relates to a nylon alloy material with metal adhesion. Background Art

[0002] Polyamide is widely used in industry because of its excellent comprehensive properties. The relevant types can be divided into PA6, PA66, PPA, and long-chain nylon (PA1010, PA612, PA12, etc.), of which PA6 and PA66 account for more than 90% of the market. At present, PA is mainly given new functions such as reinforcement, toughening, flame retardancy and other properties through physical or chemical modification to meet the use requirements of products. Nylon composite materials can be directly injected or metal inserts are injected to achieve the overall assembly of the product, especially in low-voltage electrical appliances and precision electronic products, so the bonding of metal and plastic is very important.

[0003] Currently, there are few studies on the bonding of plastics and metals, and the research mainly focuses on hot melt adhesives, adhesives and welding methods. For example, CN109986191A discloses a surface treatment method for metal / polymer connection. The metal surface is polished and cleaned and then immersed in a corrosive liquid to form a reaction layer on the surface. The reaction layer contains compound particles. At high temperatures, the molten polymer flows and can fully wet the metal substrate and the compound particles to achieve a microscopic bite and bonding effect, thereby effectively connecting the metal and polymer materials.

[0004] CN112662173A discloses a PA46 reinforced flame retardant material with high adhesion and a preparation method thereof. By adding a metal viscosity enhancer to a PA46 matrix and through the synergistic effect of the metal viscosity enhancer and a polarity regulator, the PA46 material melt and the metal have extremely high adhesion properties.

[0005] Because nylon material has a high molecular weight but weak polarity, and will experience partial crystallization and shrinkage during the melt cooling process, it results in poor bonding with metal sheets and cannot meet the use requirements of the parts. Summary of the invention

[0006] The main purpose of the present invention is to solve the problem of poor adhesion between PA12 and metal, to provide a PA12 alloy material with metal adhesion, to modify the PA12 resin, and to use an adhesive to increase the polarity of PA12, thereby improving the adhesion performance between PA12 and metal.

[0007] The technical solution adopted by the present invention to solve its technical problem is:

[0008] A nylon alloy material with metal bonding properties, comprising, by weight:

[0009] Polyamide PA12: 100

[0010] Compatibilizer: 5-20;

[0011] Adhesive: 1-10

[0012] Antioxidant: 0.1-0.5;

[0013] Lubricant: 0.2-0.6;

[0014] The adhesive is a polymer (also called phenoxy resin) prepared from bisphenol A and epoxy resin, wherein the selected bisphenol A is one of n-methylhydroquinone (NMHQ), t-butylhydroquinone (TBHQ) and diallyl bisphenol A (DABPA), and the epoxy resin has an epoxy equivalent of 150-200.

[0015] The polyamide PA12 is one of PA12 new materials or secondary brand materials;

[0016] The compatibilizer is one or more of PE-g-MAH, PP-g-MAH, and PS-g-MAH.

[0017] The adhesive is prepared by the reaction of bisphenol A and epoxy resin. The specific preparation method is as follows: The preparation method is as follows: epoxy resin, n-methylhydroquinone (NMHQ) and 1,4-dioxane are added to a three-necked flask equipped with a mechanical stirrer, a reflux condenser, a thermometer and a nitrogen inlet. The mixture is then stirred and heated rapidly to form a clear liquid. Finally, solid tetrabutylammonium bromide is added; the temperature is gradually increased to a reflux temperature of about 93-100°C, and the heating is maintained at a constant temperature. An alkaline solution is added to the system. The torque of the reactor increases, and the reaction mixture becomes a viscous liquid. Then continue to heat for 5-7 hours. After the mixture is cooled, it is poured into cold deionized water. The obtained reaction product is carefully washed with distilled water, and finally a polymer prepared from bisphenol A and epoxy resin is obtained.

[0018] Among them, the mass ratio of epoxy resin, bisphenol A and 1,4-dioxane is (9-11):(6-8):(2-4).

[0019] The antioxidant is selected from one or more of tris(2,4-di-tert-butylphenyl)phosphite, tetrakis(2,4-di-tert-butylphenyl-4,4-biphenyl)bisphosphate, N,N'-bis-(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl)hexanediamine, and tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]pentaerythritol ester.

[0020] The lubricant is one or more of ethylene-acrylic acid copolymer, calcium stearate and aluminum stearate.

[0021] The present invention also provides a method for preparing a PA12 material having metal adhesion, the steps of which are as follows:

[0022] Place PA 12 in a vacuum dehumidification drying oven for drying at a temperature of 90-100°C for 4-6 hours;

[0023] The dried PA12, compatibilizer, bonding compound, antioxidant, lubricant, etc. are mixed evenly in a high-speed mixer, and then the mixed materials are placed in a parallel co-rotating twin-screw extruder for melt extrusion and granulation to obtain a PA12 alloy material with bonding metal.

[0024] In some embodiments, the screw speed of the twin-screw extruder is 100-300 r / min, and the machine temperature is set to 200-250°C.

[0025] Compared with the background technology, this technical solution has the following advantages:

[0026] 1. For PA12 materials, the present invention adds metal adhesive to the PA12 substrate and adjusts it with a compatibilizer so that PA12 has high adhesion to metal in a molten state and can be applied to plastic products that need to be bonded to metal.

[0027] 2. The prior art has little research on the molten bonding performance of nylon materials and metals, and mainly focuses on the research on nylon hot melt adhesives, adhesives, and welding methods. The present invention modifies the nylon substrate to obtain an adhesive with very high metal bonding performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 .Test method for plastic / metal bonding performance DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. 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.

[0030] The present invention provides the following embodiments

[0031] Example 1

[0032] PA12 100 parts, PE-g-MAH 5 parts, binder 2 parts, N,N'-bis-(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl)hexanediamine 0.2 parts, calcium stearate 0.3 parts

[0033] The adhesive is a phenoxy resin prepared from n-methylhydroquinone (NMHQ) and epoxy resin.

[0034] The phenoxy resin was prepared by the following method:

[0035] Epoxy resin, n-methylhydroquinone (NMHQ) and 1,4-dioxane are added to a three-necked flask equipped with a mechanical stirrer, a reflux condenser, a thermometer and a nitrogen inlet: the mass parts of the three are 100 parts, 70 parts and 30 parts respectively. The mixture is then stirred and heated rapidly to form a clear liquid. Finally, solid tetrabutylammonium bromide is added; the temperature is gradually increased to the reflux temperature of about 93-100°C and the temperature is maintained. 3 parts of 40% KOH solution are added to the system. The torque of the reactor increases and the reaction mixture becomes a viscous liquid. Then continue heating for about 6 hours. The mixture is cooled and poured into cold deionized water. The obtained reaction product is carefully washed with distilled water, and finally a phenoxy resin prepared from n-methylhydroquinone (NMHQ) and epoxy resin is obtained.

[0036] The preparation of nylon alloy material with metal bonding properties is as follows:

[0037] Step 1: Place PA 12 in a vacuum dehumidification drying oven for drying at a temperature of 95°C for 5 hours;

[0038] Step 2: Mix the dried PA12, compatibilizer, bonding compound, antioxidant, lubricant, etc. in a high-speed mixer, and then place the mixed materials in a parallel co-rotating twin-screw extruder for melt extrusion and granulation to obtain a PA12 alloy material with bonding metal. The screw speed of the twin-screw extruder is 200r / min, and the machine temperature is set to 200-250°C.

[0039] Example 2

[0040] 100 parts of PA12, 10 parts of PE-g-MAH, 4 parts of adhesive, 0.2 parts of pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, and 0.3 parts of ethylene-acrylic acid copolymer.

[0041] The adhesive is a phenoxy resin prepared from t-butyl hydroquinone (TBHQ) and epoxy resin, and the preparation method comprises the following steps:

[0042] Epoxy resin, t-butyl hydroquinone (TBHQ) and 1,4-dioxane were added to a three-necked flask equipped with a mechanical stirrer, a reflux condenser, a thermometer and a nitrogen inlet, and the mass parts of the three were 100 parts, 70 parts and 30 parts respectively. The mixture was then stirred and heated rapidly to form a clear liquid. Finally, solid tetrabutylammonium bromide was added; the temperature was gradually increased to the reflux temperature of about 93-100°C and the temperature was maintained. 3 parts of 40% KOH solution were added to the system. The torque of the reactor increased and the reaction mixture became a viscous liquid. Then the heating was continued for about 6 hours. The mixture was cooled and poured into cold deionized water. The obtained reaction product was carefully washed with distilled water, and finally a phenoxy resin prepared from t-butyl hydroquinone (TBHQ) and epoxy resin was obtained.

[0043] The method for preparing the nylon alloy material with metal adhesion is the same as that in Example 1.

[0044] Example 3

[0045] PA12 sub-brand 100 parts, SEBS-g-MAH 5 parts, phenoxy resin prepared from t-butyl hydroquinone (TBHQ) and epoxy resin 2 parts, pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate] 0.2 parts, ethylene-acrylic acid copolymer 0.3 parts

[0046] The adhesive is a phenoxy resin prepared from diallyl bisphenol A (DABPA) and epoxy resin, and the preparation method comprises the following steps:

[0047] Epoxy resin, diallyl bisphenol A (DABPA) and 1,4-dioxane were added to a three-necked flask equipped with a mechanical stirrer, a reflux condenser, a thermometer and a nitrogen inlet, and the mass parts of the three were 100 parts, 70 parts and 30 parts respectively. The mixture was then stirred and heated rapidly to form a clear liquid. Finally, solid tetrabutylammonium bromide was added; the temperature was gradually increased to the reflux temperature of about 93-100°C and the temperature was maintained. The torque of the reactor increased when 3 parts of 40% KOH solution were added to the system, and the reaction mixture became a viscous liquid. Then continue heating for about 6 hours. The mixture was cooled and poured into cold deionized water. The obtained reaction product was carefully washed with distilled water, and finally a phenoxy resin prepared from diallyl bisphenol A (DABPA) and epoxy resin was obtained.

[0048] The method for preparing the nylon alloy material with metal adhesion is the same as that in Example 1.

[0049] Comparative Example 1

[0050] The "PA12 100 parts" in Example 1 is replaced by "PA6 100 parts", and the rest is the same as Example 1

[0051] Comparative Example 2

[0052] The "PE-g-MAH 5 parts" in Example 1 was replaced by "PE 5 parts", and the rest was the same as in Example 1

[0053] Comparative Example 3

[0054] The adhesive component in Example 1 is removed, and the rest is the same as Example 1.

[0055] Comparative Example 4

[0056] The "PA12 100 parts" in Example 1 is replaced by "PA12 nozzle material 100 parts", and the rest is the same as Example 1

[0057] The composite materials prepared in the above examples and comparative examples were tested for relevant indicators, wherein the tensile strength and elongation at break were tested in accordance with GB / T1040-2006, and the plastic and metal bonding test was performed at a speed of 1 mm / min to test the plastic and metal bonding performance. Figure 1 The strength of the test specimens was tested by pulling them apart in the direction shown.

[0058] The test results are as follows:

[0059] Serial number Tensile strength(MPa) Elongation at break (%) Plastic / metal aluminum plate bonding load (N) Example 1 40 7.5 72 Example 2 38 7.9 65 Example 3 41 7.7 76 Comparative Example 1 75 5.3 31 Comparative Example 2 32 5.6 23 Comparative Example 3 41 6.6 12 Comparative Example 4 31 6.5 48

[0060] It can be seen from Table 1 that the prepared PA12 alloy material with metal adhesion has excellent tensile strength, elongation at break and metal adhesion performance. By comparing Example 1 and Comparative Example 3, it can be seen that by adding a compatibilizer and a metal adhesive, the adhesion between the PA12 alloy material and the metal aluminum plate can be effectively improved.

[0061] The above description is only a preferred embodiment of the present invention, and therefore cannot be used to limit the scope of the present invention. That is, equivalent changes and modifications made according to the patent scope of the present invention and the contents of the specification should still fall within the scope of the present invention.

Claims

1. A PA12 alloy material with metal bonding properties, comprising, by weight: Polyamide PA12: 100 Compatibilizer: 5-20; Adhesive: 1-10 Antioxidant: 0.1-0.5; Lubricant: 0.2-0.6; The adhesive is a polymer prepared from bisphenol A and epoxy resin, the bisphenol A is one of t-butyl hydroquinone and diallyl bisphenol A, and the epoxy equivalent of the epoxy resin is 150-200; The PA12 is one of new material or secondary brand material; The compatibilizer is one or more of PE-g-MAH, PP-g-MAH, and PS-g-MAH; The adhesive preparation method comprises: adding epoxy resin, bisphenol A and 1,4-dioxane into a three-necked flask equipped with a mechanical stirrer, a reflux condenser, a thermometer and a nitrogen inlet; The mixture is then rapidly stirred and heated to form a clear liquid; solid tetrabutylammonium bromide is finally added; the temperature is gradually increased to a reflux temperature of 93-100°C and the heating is maintained at a constant temperature; an alkali solution is then added to the system; the reaction mixture becomes a viscous liquid; heating is then continued for 5-7 hours; the mixture is cooled and poured into cold deionized water; the obtained reaction product is washed with distilled water, and finally a polymer prepared from bisphenol A and epoxy resin is obtained.

2. The PA12 alloy material with metal adhesion according to claim 1, characterized in that: The mass ratio of epoxy resin, bisphenol A and 1,4-dioxane is (9-11):(6-8):(2-4).

3. The PA12 alloy material with metal adhesion according to claim 1, characterized in that: The antioxidant is selected from one or more of tris(2,4-di-tert-butylphenyl)phosphite, tetrakis(2,4-di-tert-butylphenyl-4,4-biphenyl)bisphosphate, N,N'-bis-(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl)hexanediamine, and tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]pentaerythritol ester.

4. The PA12 alloy material with metal adhesion according to claim 1, characterized in that: The lubricant is one or more of ethylene-acrylic acid copolymer, calcium stearate and aluminum stearate.

5. The PA12 alloy material with metal adhesion according to any one of claims 1 to 4, characterized in that: The preparation method comprises the following steps: uniformly mixing PA12, a compatibilizer, an adhesive, an antioxidant and a lubricant in a high-speed mixer, adding the mixture into the main feed of a parallel co-rotating twin-screw extruder, melt-blending the materials in the screw, extruding and granulating the materials, and obtaining the PA12 alloy material with metal adhesion.

6. The PA12 alloy material with metal adhesion according to claim 5, characterized in that: The process parameters of the parallel co-rotating twin-screw extruder are as follows: the speed of the extruder is 200-300 r / min, and the machine temperature is set at 200-250°C.

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