CN105385151A - High performance polyamide 6 based friction material and preparation method thereof - Google Patents

Abstract

The invention discloses a high-performance polyamide 6-based friction material and a preparation method thereof. The friction material comprises: polyamide 6: 55% to 65%, chopped glass fiber: 10% to 15%, and composite Solid lubricant: 10% to 15%, compatibilizer: 2% to 5%, flame retardant: 10% to 15%, antistatic agent: 0.5% to 2%, antiaging agent: 0.05% to 0.5%, Silane coupling agent: 0.5% to 1%; after mixing all the materials according to the mass ratio, the high-performance polyamide 6-based friction material is prepared by melting method. The friction material has the advantages of simple manufacturing process, low wear rate, low friction coefficient, high strength, flame retardancy, antistatic, high and low temperature resistance, corrosion resistance, aging resistance, and low cost.

Description

A high-performance polyamide 6-based friction material and its preparation method

technical field

The invention relates to the field of polymer material modification, in particular to a high-performance polyamide 6-based friction material and a preparation method thereof.

Background technique

Polyamide 6 has the characteristics of high mechanical strength, good toughness, excellent electrical properties, shock resistance and sound absorption, resistance to weak acids and bases and some organic solvents, excellent self-lubricating properties, and easy molding and processing. It is widely used in the manufacture of bearings, gears, and cams in industrial production. , Various rollers, pulleys and other friction components. However, its poor dimensional stability, high water absorption, high friction coefficient during dry friction, thermal and mechanical properties are not enough to cope with high-speed friction and other shortcomings, so its application is still limited.

In recent years, the addition of fibers and inorganic particles to improve the wear resistance and mechanical properties of polyamide 6 at home and abroad often increases the friction coefficient; while the addition of solid lubricants can reduce the friction coefficient, but may increase the wear rate, Reduce its mechanical properties; add flame retardant, antistatic agent to prepare flame retardant antistatic composite material, mechanical properties and friction and wear properties decrease, high strength, flame retardant, wear-resistant polyamide 6 composite material preparation urgently needs to be solved.

Patent CN103102A introduces a preparation method of a high-impact, flame-retardant and wear-resistant polyamide 6 composite material, and obtains a polyamide 6 composite material with high impact strength and oxygen index, but its friction coefficient and wear are still relatively large.

In response to this situation, the present invention innovatively adds glass fiber and composite solid lubricant to the polyamide 6 matrix to exert its synergistic effect, and prepares a kind of lubricant with low wear rate and low friction coefficient with the addition of flame retardant and antistatic agent. The high-performance polyamide 6-based friction material with low weight, high strength, flame retardancy and antistatic has very important practical significance.

Contents of the invention

The purpose of the present invention is to provide a high-performance polyamide 6-based friction material with low wear rate, low friction coefficient, high strength, flame retardancy, antistatic, high and low temperature resistance, corrosion resistance and aging resistance.

In order to achieve the above object, the present invention includes: polyamide 6 resin: 55-65% (weight), chopped glass fiber: 10-15% (weight), composite solid lubricant: 10-15% (weight), compatibilization Agent: 3-5% (weight), flame retardant: 10-15% (weight), antistatic agent: 0.5-2% (weight), anti-aging agent: 0.05-0.5% (weight), silane coupling agent : 0.5-1% (weight), wherein the particle size of the composite solid lubricant is 5-10 μm, composed of polytetrafluoroethylene and ultra-high molecular weight polyethylene with a mass ratio of 1:1-2:1 or composed of polytetrafluoroethylene and ultra-high molecular weight polyethylene with a mass ratio of 1 : 1 to 2: 1 polytetrafluoroethylene, graphite powder or composed of polytetrafluoroethylene, ultra-high molecular weight polyethylene, graphite powder with a mass ratio of 1: 1: 1; the compatibilizer is HDPE-g -MAH or POE-g-MAH; the flame retardant is antimony trioxide and tetradetrabromodiphenoxybenzene with a mass ratio of 1:3 to 1:4 or a mass ratio of 1:3 to 1: Antimony trioxide and decabromodiphenyl ether in 4; the antistatic agent is ethoxylated alkylamine; the antiaging agent is antioxidant 1010.

Preferably, the relative viscosity of the polyamide 6 resin is 2.80-2.95.

Preferably, the chopped glass fibers are E glass fibers with a length of 3-5 mm.

Another object of the present invention is to provide a kind of preparation method of high-performance polyamide 6 base friction material, comprising: 1) by polyamide 6 resin: 55～65% (weight), chopped glass fiber: 10～15% ( weight), composite solid lubricant: 10-15% (weight), compatibilizer: 3-5% (weight), flame retardant: 10-15% (weight), antistatic agent: 0.5-2% (weight ), anti-aging agent: 0.05～0.5% (weight), silane coupling agent: 0.5～1% (weight) ingredients, wherein the particle size of the composite solid lubricant is 5～10 μm, and the mass ratio is 1:1～2: 1 of polytetrafluoroethylene and ultra-high molecular weight polyethylene or composed of polytetrafluoroethylene and graphite powder with a mass ratio of 1:1 to 2:1 or composed of polytetrafluoroethylene and ultra-high molecular weight polyethylene with a mass ratio of 1:1:1 Composed of high molecular weight polyethylene and graphite powder; the compatibilizer is HDPE-g-MAH or POE-g-MAH; the flame retardant is antimony trioxide with a mass ratio of 1:3 to 1:4 , Tetrabromodiphenoxybenzene or antimony trioxide and decabromodiphenyl ether with a mass ratio of 1:3 to 1:4; the antistatic agent is ethoxylated alkylamine; the The anti-aging agent is antioxidant 1010; 2) mixing uniformly; 3) extruding and granulating at 190-250° C.; 4) drying to remove water.

Preferably, the relative viscosity of the polyamide 6 resin is 2.80-2.95.

Preferably, the chopped glass fibers are E glass fibers with a length of 3-5 mm.

The present invention selects the polyamide 6 that has good wear resistance, toughness, mechanical strength and relatively cheap price, and is easy to shape as the matrix material, overcomes the need to adopt polytetrafluoroethylene (PTFE), polyimide (PI), polyether Ether ketone (PEEK), polyphenylene sulfide (PPS), etc. are the disadvantages of harsh molding conditions and high prices when used as base materials. Glass fiber has high strength and rigidity, good thermal conductivity, small elongation and thermal expansion coefficient, and can withstand the corrosion of many media, does not burn, and has good temperature resistance in an environment below 250 ° C, so glass fiber is used Fiber-reinforced polyamide 6 can obtain friction materials with good mechanical properties, wear resistance and heat resistance, and prolong the service life of products. The solid lubricant has the effect of anti-wear and anti-friction due to the formation of a low-shear strength transfer film on the contact interface during the friction process; the selection of a composite solid lubricant can not only play the role of lubrication, but also effectively prevent the glass fiber from being exposed , thereby greatly improving the friction and wear properties of the material. The fiber in the friction material acts as a reinforcement to ensure mechanical properties and improve wear resistance and thermal stability; since the composite solid lubricant reduces the friction coefficient, the performance of the polyamide 6 is improved. The invention has the advantages of simple production process, low cost, excellent friction and wear, flame retardancy, antistatic and thermal properties, and maintains the excellent mechanical properties of the material. Compared with the single solid lubricant, the composite solid lubricant has a synergistic effect, and the prepared material has lower friction coefficient and wear rate at the same time. PTFE significantly reduces the friction coefficient of the material. While graphite reduces the friction coefficient, it increases the thermal conductivity of the material, so that the friction heat can be quickly exported, slowing down the melting of the material during the friction process, and at the same time reducing the surface resistance of the material. When high molecular weight polyethylene, polytetrafluoroethylene and graphite are used together, there is a significant synergistic effect. The polyamide 6 composite material modified by the three synergistically has a lower friction coefficient and wear than the composite material modified by a single solid lubricant On this basis, the preferred flame retardant and antistatic agent are added to obtain a high-performance polymer with low wear rate, low friction coefficient, high strength, flame retardancy, antistatic, high and low temperature resistance, corrosion resistance and aging resistance. Amide 6 based friction material. The following basic properties are obtained by analyzing and evaluating the materials prepared under the optimized process with a suitable formula. Axial tensile strength ≥60MPa, notched impact strength ≥25KJ/m ² , service temperature -30～150°C, density ≥1.62g/cm ³ , flame retardant performance: V-0, surface resistance <5×10 ⁸ Ω; Friction coefficient: 0.02～0.13, wear rate 4.5×10 ^-6 ～3.31×10 ^-5 mm ³ /Nm. The polyamide 6-based friction material of the invention has the characteristics of high performance, wide application range and broad market prospect.

detailed description:

The following examples are given to describe the present invention in detail, but not to limit the scope of the invention.

Example 1

1) According to polyamide 6 resin: 55% (weight), 3-5mm E glass fiber: 15% (weight), polytetrafluoroethylene: 7% (weight), POE-g-MAH: 3.5% (weight) ;Graphite: 3.5% by weight, decabromodiphenyl ether: 10% by weight, antimony trioxide: 3% by weight, ethoxylated alkylamine: 2% by weight, antioxidant 1010 : 0.5% (weight), silane coupling agent: 0.5% (weight) batching; 2) high-speed mixing for 0.5 hours, rotating speed is 300～600 rev/min mixing; 3) the temperature of the twin-screw extruder is controlled at 190～ Mix and extrude at 250°C, water-cool and cut into pellets with a specification of Φ2.5×4 through a pelletizer; 4) Dry at 100°C for 3 hours.

The materials of this formula are analyzed and evaluated, and the following basic properties are obtained. Axial tensile strength: 67MPa, notched impact strength: 27.7KJ/m ² , flame retardancy: V-0, surface resistance: 4.2×10 ⁸ Ω; friction coefficient: 0.08, wear rate: 5.5×10 ^-6 mm ³ /Nm.

Example 2

1) According to polyamide 6 resin: 58% (weight), E glass fiber of 3 ~ 5mm: 12.5% (weight), polytetrafluoroethylene: 6% (weight), HDPE-g-MAH: 3.5% (weight) ; UHMWPE: 3% by weight, Decabromodiphenyl ether: 11% by weight, Antimony trioxide: 3.5% by weight, Ethoxylated alkylamine: 1.5% by weight, Antioxidant 1010: 0.5% (weight), silane coupling agent: 0.5% (weight) batching; 2) high-speed mixing for 0.5 hours, and the rotating speed is 300～600 rpm to mix evenly; 3) the temperature of the twin-screw extruder Mixing and extrusion controlled at 190-250°C, water-cooled and cut into pellets with a specification of Φ2.5×4 by a pelletizer; 4) Drying at 100°C for 3 hours.

The materials of this formula are analyzed and evaluated, and the following basic properties are obtained. Axial tensile strength: 65.3MPa, notched impact strength: 25.8KJ/m ² , flame retardancy: V-0, surface resistance: 4.4×10 ⁸ Ω; friction coefficient: 0.1, wear rate: 4.5×10 ^-6 mm ³ /Nm.

Example 3

1) According to polyamide 6 resin: 65% (weight), E glass fiber of 3 ~ 5mm: 10% (weight), polytetrafluoroethylene: 3.5% (weight), HDPE-g-MAH: 2% (weight) , ultra-high molecular weight polyethylene: 3.5% (weight), graphite: 3.5% (weight), tetradecabromodiphenoxybenzene: 8.5% (weight), antimony trioxide: 2.5% (weight), ethoxy Alkylamine: 0.8% (weight), antioxidant 1010: 0.2% (weight), silane coupling agent: 0.5% (weight) ingredients; 2) high-speed mixing for 0.5 hours, rotating speed is 300～600 rev/min mixing Uniform; 3) The temperature of the twin-screw extruder is controlled at 190-250°C for mixing and extrusion, water-cooled and cut into pellets with a specification of Φ2.5×4 by a pelletizer; 4) Drying at 100°C for 3 hours.

The materials of this formula are analyzed and evaluated, and the following basic properties are obtained. Axial tensile strength: 63.5MPa, notched impact strength: 27.8KJ/m ² , flame retardancy: V-0, surface resistance: 4.0×10 ⁸ Ω; friction coefficient: 0.05, wear rate: 3.3×10 ^-6 mm ³ /Nm.

Claims (6)

1. a high-performance polyamide 6 base frication material, it is characterized in that, comprise: polyamide 6: 55 ~ 65% (weight), short glass fiber: 10 ~ 15% (weight), composite solid lubricating agent: 10 ~ 15% (weight), expanding material: 3 ~ 5% (weight), fire retardant: 10 ~ 15% (weight), static inhibitor: 0.5 ~ 2% (weight), antiaging agent: 0.05 ~ 0.5% (weight), silane coupling agent: 0.5 ~ 1% (weight), wherein composite solid lubricating agent particle diameter is 5 ~ 10 μm, be the tetrafluoroethylene of 1: 1 ~ 2: 1 by mass ratio, ultrahigh molecular weight polyethylene(UHMWPE) forms or is 1: 1 ~ 2: 1 tetrafluoroethylene by mass ratio, Graphite Powder 99 forms or is the tetrafluoroethylene of 1: 1: 1 by mass ratio, ultrahigh molecular weight polyethylene(UHMWPE), Graphite Powder 99 forms, described expanding material is HDPE-g-MAH or POE-g-MAH, described fire retardant to be mass ratio be 1: 3 ~ 1: 4 antimonous oxide, ten tetrabromo two phenoxy group benzene or mass ratio be 1: 3 ~ 1: 4 antimonous oxide, decabromodiphynly oxide, described static inhibitor is ethoxylated alkylamine, described antiaging agent is antioxidant 1010.

2. a kind of high-performance polyamide 6 base frication material according to claim 1, is characterized in that, the relative viscosity of described polyamide 6 is 2.80 ~ 2.95.

3. a kind of high-performance polyamide 6 base frication material according to claim 1, is characterized in that, described short glass fiber is the E glass fibre of length 3 ~ 5mm.

4. the preparation method of a high-performance polyamide 6 base frication material, it is characterized in that, comprise: 1) by polyamide 6: 55 ~ 65% (weight), short glass fiber: 10 ~ 15% (weight), composite solid lubricating agent: 10 ~ 15% (weight), expanding material: 3 ~ 5% (weight), fire retardant: 10 ~ 15% (weight), static inhibitor: 0.5 ~ 2% (weight), antiaging agent: 0.05 ~ 0.5% (weight), silane coupling agent: 0.5 ~ 1% (weight) prepares burden, wherein composite solid lubricating agent particle diameter is 5 ~ 10 μm, be the tetrafluoroethylene of 1: 1 ~ 2: 1 by mass ratio, ultrahigh molecular weight polyethylene(UHMWPE) forms or is 1: 1 ~ 2: 1 tetrafluoroethylene by mass ratio, Graphite Powder 99 forms or is the tetrafluoroethylene of 1: 1: 1 by mass ratio, ultrahigh molecular weight polyethylene(UHMWPE), Graphite Powder 99 forms, described expanding material is HDPE-g-MAH or POE-g-MAH, described fire retardant to be mass ratio be 1: 3 ~ 1: 4 antimonous oxide, ten tetrabromo two phenoxy group benzene or mass ratio be 1: 3 ~ 1: 4 antimonous oxide, decabromodiphynly oxide, described static inhibitor is ethoxylated alkylamine, described antiaging agent is antioxidant 1010, 2) mix, 3) at 190 ~ 250 DEG C of extruding pelletizations, 4) dry removing moisture.

5. the preparation method of a kind of high-performance polyamide 6 base frication material according to claim 4, is characterized in that, the relative viscosity of described polyamide 6 is 2.80 ~ 2.95.

6. the preparation method of a kind of high-performance polyamide 6 base frication material according to claim 4, is characterized in that, described short glass fiber is the E glass fibre of length 3 ~ 5mm.