CN1270188A - Water-proof antiwear self-lubricating material and preparing process thereof - Google Patents

Abstract

A water-resistant, low-density, wear-resistant self-lubricating polymer composite material suitable for water medium, composed of thermoplastic high-temperature resistant polymers such as polyether ether ketone and polyimide, graphite, nano-silicon carbide and nano-silicon dioxide, etc. Composed of nanoparticles, its products have good machinability, excellent water resistance, wear resistance and self-lubricating properties, heat resistance, radiation resistance, suitable for special environments such as water medium, humidity, radiation, corrosion, etc., and can be widely used In transportation, energy, water conservancy, machinery, chemical industry, instrumentation, medical treatment, food, household small electrical appliances and other industries.

Description

Water-resistant and wear-resistant self-lubricating material and preparation method thereof

The invention relates to a water-resistant and wear-resistant self-lubricating filled polymer composite material suitable for water medium and a preparation method thereof.

Self-lubricating high wear-resistant materials are a new class of special-purpose materials developed in the field of tribology in recent years to solve the friction and wear problems of materials under specific working conditions. The wear resistance of ordinary polymers and their composites in aqueous media and humid environments is significantly reduced, and their wear rates are 10 to 20 times that of dry friction conditions. How to solve the problem of polymer composites in aqueous media and humid environments? The problem of friction and wear is a technical problem that urgently needs to be solved in today's national infrastructure and civilian daily life.

As a large class of materials, various filler-filled reinforced polymer composites have been widely used in many fields, and have solved many major technical problems that cannot be solved by other materials. As a new type of material with unique properties, nanomaterials have become a hot spot in material science research across the century, and its development has added new content to the research and application of conventional materials. At present, nano-materials have made great progress in the field of metal materials and ceramic materials, while the research and application in the field of polymer materials has just started, and there is no relevant information about this kind of filling materials used in water media to neutralize humid environment conditions at home and abroad. The research and application reports of wear-resistant self-lubricating polymer composite materials used in the past have not yet seen relevant patent reports.

The purpose of the present invention is to provide a water-resistant, low-density, wear-resistant and self-lubricating filled polymer composite material to solve the adaptability of the material and the related tribological problems under the conditions of water medium and humid environment.

Another object of the present invention is to provide a method for preparing the above-mentioned water-resistant and anti-wear self-lubricating filled polymer composite material.

The object of the present invention is achieved through the following measures:

The composition weight percentage of water-resistant wear-resistant self-lubricating material of the present invention is:

Polyetheretherketone 35～80

Polyimide 5～50

Stone ink 5～40

Nano silicon carbide 2.5～20

Nano silica 0～20

Nano-silicon carbide and nano-silicon dioxide with a particle diameter of less than 100 nm, and graphite with a particle diameter of less than 25 μm are selected.

The viscosity of polyetheretherketone is η=0.6-0.9, and the raw powder of polyetheretherketone with a particle size of less than 100 μm is selected.

The polyimide is a meltable polyimide, and the polyimide raw powder with a powder particle size of less than 100 μm is selected.

The preparation method of the present invention comprises the steps in turn:

(1) Weigh nano-silicon carbide 2.5-20 and silicon dioxide 0-20, add a solvent sufficient to wet the material, and treat it with ultrasonic waves to make it fully dispersed and even. The added solvent can be ethanol, and chlorinated One of the hydrocarbon solvents;

(2) Weigh polyether ether ketone 35-80, polyimide 5-50 and graphite 5-40, add to the nanoparticle dispersion prepared according to (1), and process it by ultrasonic wave or ball milling , fully mixed and dispersed evenly, and allowed to dry;

(3) Put the mixture treated according to (2) into the mold, pressurize to 3MPa, then raise the temperature at a rate of 10°C/min, wait until the temperature rises to 300-350°C, keep the temperature constant for 15 minutes, and then pressurize to 5~15MPa, and continue to heat up to 360~380°C, keep the temperature for 10~60 minutes, then cool under the condition of holding pressure, and use natural cooling or rapid cooling with ice to make the mold temperature drop below 100°C for demoulding. In order to prevent the generation of air bubbles during the above hot pressing process, attention should be paid to degassing at any time.

The present invention selects polyether ether ketone and heat-resistant polyimide as main materials to ensure that the product has excellent strength and heat resistance, and also considers the feasibility of the process. The polyether ether ketone used has a glass transition temperature of 143°C and a melting point of 334°C. This material has excellent mechanical properties and chemical corrosion resistance. The polyimide used is fusible polyimide, which has excellent process adaptability, mechanical properties and high temperature resistance.

The present invention selects nano-silicon carbide, silicon dioxide and graphite as fillers to ensure that the product has low friction coefficient and wear rate, and has good mechanical properties and water resistance.

After hot pressing and constant temperature in the present invention, the choice of cooling method can control the crystallization state of the polymer material in the product, and then affect the performance of the product. Generally speaking, the product that is naturally cooled with the furnace has good flexibility, and the rigidity of the product that is rapidly cooled with ice is better.

The biggest feature of the product of the invention is that it has excellent wear resistance and low friction coefficient under the conditions of water medium and humid environment. At the same time, this product also has the characteristics of high temperature resistance, low density, radiation resistance and other special environments. This product has good machinability and is suitable for making small parts of various shapes.

The main performance index of product of the present invention is as follows:

1. Density 1.44～1.85g/ ^cm3

2. Bending strength ≥130MPa

3. Hardness 28～38 HBS(5/62.5/60)

4. Friction coefficient 0.06～0.16

5. Wear rate <4.5×10 ^-6 mm ³ /(Nm)

6. Applicable temperature range -100℃～+250℃.

The product of the present invention is suitable for making friction and wear parts with low friction and high wear resistance under the conditions of water medium and humid environment, and can be used in transportation, energy, agriculture and water conservancy departments that require water resistance, low density, wear resistance and self-lubrication, as Bearings, gears, sliders, piston rings and other components; due to their good radiation resistance and temperature resistance, they are also suitable for some parts of nuclear reactors; in addition, because they are pollution-free and pollution-free, they can also be widely used in Machinery, chemical industry, instrumentation, food, medical equipment, household small electrical appliances and other industries.

Example 1

Weigh 3g of nano-silicon carbide and 2g of nano-silicon dioxide, add 50ml of ethanol, add 15g of fusible polyimide, 30g of polyether ether ketone and 5g of graphite after ultrasonic treatment for 5 minutes, ball mill for 3 hours, and then the The mixture was dried with infrared rays to remove solvent and water vapor. Put it into a mold for hot pressing, pressurize to 3MPa, heat up at a rate of 10°C/min, wait until the temperature rises to 300°C, keep the temperature constant for 15 minutes, then pressurize to 5MPa, and continue to heat up to 380°C, keep the temperature for 20 minutes, Then cool naturally under the condition of holding pressure, when the mold temperature drops below 100°C, it can be demolded. The material properties meet the above indicators. Deflate every 5 minutes during the above hot pressing process. Example 2

Weigh 2 g of nano-silicon carbide, add 50 ml of chloroform, and treat with ultrasonic waves for 5 minutes. Add 5g of meltable polyimide, 40g of polyether ether ketone and 10g of graphite, after ball milling for 4 hours, remove the solvent and water vapor by heating and vacuum drying, and put it into a mold for hot pressing. Pressurize to 3MPa, heat up at a rate of 10°C/min, wait until the temperature rises to 320°C, keep the temperature for 15 minutes, then pressurize to 5MPa, and continue to heat up to 375°C, keep the temperature for 25 minutes, and then use the The ice is rapidly cooled, and when the mold temperature drops below 100°C, it can be demolded. The material properties meet the above indicators. Deflate every 5 minutes during the above hot pressing process. Example 3

Weigh 1 g of nano-nano silicon carbide and 2 g of silicon dioxide, add them into 50 ml of ethanol and sonicate for 5 to 10 minutes, then add 5 g of polyimide, 30 g of polyether ether ketone and 5 g of graphite, and then sonicate for 15 minutes and mix well. The mixture is heated and dried in a vacuum to remove solvent and water vapor, and then put into a mold for thermocompression molding. Pressurize to 3MPa, heat up at a heating rate of 10°C/min, wait until the temperature rises to 300°C, keep the temperature for 15 minutes, then pressurize to 5MPa, and continue to heat up to 370°C, keep the temperature for 30 minutes, and then naturally Cool, when the mold temperature drops below 100°C, it can be demolded. The material properties meet the above indicators. During the above hot pressing process, deflate every 5 minutes. Example 4

Weigh 3g of nano-silicon carbide, add 50ml of ethanol, and treat with ultrasonic wave for 5 minutes. Add 15g of meltable polyimide, 15g of polyetheretherketone and 5g of graphite, after ball milling for 4 hours, remove the solvent and water vapor by heating and vacuum drying, and put it into a mold for hot pressing. Pressurize to 3MPa, heat up at a rate of 10°C/min, wait until the temperature rises to 340°C, keep the temperature constant for 25 minutes, then pressurize to 5MPa, and continue to heat up to 380°C, keep the temperature constant for 25 minutes, and then use the The ice is rapidly cooled, and when the mold temperature drops below 100°C, it can be demolded. The material properties meet the above indicators. Deflate every 5 minutes during the above hot pressing process. Example 5

Weigh 2g of nano-silicon carbide and 1g of nano-silicon dioxide, add 50ml of ethanol, add 5g of fusible polyimide, 40g of polyether ether ketone and 10g of graphite after ultrasonic treatment for 15 minutes, ball mill for 3 hours, and then the The mixture was dried with infrared rays to remove solvent and water vapor. Put it into a mold for hot pressing, pressurize to 3MPa, heat up at a rate of 10°C/min, wait until the temperature rises to 320°C, keep the temperature constant for 15 minutes, then pressurize to 5MPa, and continue to heat up to 370°C, keep the temperature for 20 minutes, Then cool naturally under the condition of holding pressure, when the mold temperature drops below 100°C, it can be demolded. The material properties meet the above indicators. Deflate every 5 minutes during the above hot pressing process.

Claims (2)

1. water-proof antiwear self-lubricating polymer composite is characterized in that forming weight percentage and is:

Polyether-ether-ketone 35～80

Polyimide 5～50

Graphite 5～40

Nanometer silicon carbide 2.5～20

Nano silicon 0～20

Wherein, the mean particle dia of nanometer silicon carbide and nano silicon is less than 100nm, and the particle diameter of graphite is less than 25 μ m, and the viscosity of polyether-ether-ketone is η=0.6～0.9; Polyimide is an ANALYSIS OF MOLDABLE POLYIMIDES.

2. preparation methods according to claim 1 is characterized in that:

(1) take by weighing nanometer silicon carbide 2.5～20 and silicon-dioxide 0～20, adding is enough to make the material profit

Wet solvent is handled with ultrasonic wave, and it fully is uniformly dispersed, and the solvent that is added can

Being ethanol, and a kind of in the chlorinated hydrocarbon solvent;

(2) take by weighing polyether-ether-ketone 35～80 and polyimide 5～50 and graphite 5～40, be added to by

(1) in the made nanoparticle dispersion liquid, handle with the method for ultrasonic wave or ball milling,

Thorough mixing is uniformly dispersed, and makes its drying;

(3) mixture after will handling by (2) be put into mould, be forced into 3MPa, then with

10 ℃/minute heat-up rate heats up, and treats that temperature rises to 300～350 ℃, constant temperature 15 minutes,

Be forced into 5～15MPa then, and continue to be warming up to 360～380 ℃, constant temperature 10～60 minutes,

Under the pressurize condition, cool off then, adopt naturally cooling or make mould with the method for icing quick cooling

Temperature drops to 100 ℃ with bottom knockout.