Preparation method of antistatic polyether-ether-ketone composite material with high dimensional stability

Abstract

The invention discloses a preparation method of an antistatic polyether-ether-ketone composite material with high dimensional stability. The preparation method sequentially comprises the following steps: S1, preparing the following raw materials in parts by mass: 50-80 parts of polyether-ether-ketone, 10-30 parts of conductive titanium dioxide, 3-20 parts of metal sulfide and 0.1-10 parts of a processing aid; s2, mixing the polyether-ether-ketone and the processing aid in a rotary mixer according to a ratio, feeding the mixture from a main feed opening of a twin-screw extruder, feeding the conductive titanium dioxide and the metal sulfide from a side feed opening of the extruder through a feeder, and performing melt mixing, extrusion and granulation; s3, the rotation speed of the rotary mixer in the step S2 is 60-120 rpm, and the mixing time is 5-10 min. According to the invention, a mode of filling and blending PEEK with the conductive titanium dioxide and the metal sulfide is adopted, the warping property of a matrix is improved by utilizing the characteristic of good isotropy of the spherical form of the titanium dioxide, and the titanium dioxide has a whitening effect and is suitable for the appearance requirements of white parts.

Description

Technical Field

[0001] The invention relates to the field of engineering plastic composite materials, and in particular to a method for preparing a polyetheretherketone composite material with high dimensional stability and antistatic properties. Background Art

[0002] Polyetheretherketone, also known as polyetheretherketone (PEEK for short), is a linear aromatic polymer compound with chain links in the main chain of the molecule. It is an ultra-high performance special engineering plastic developed by the British Imperial Chemical Industries (ICI) in 1978. It has high mechanical strength, high temperature resistance, impact resistance, flame retardancy, acid and alkali resistance, hydrolysis resistance, wear resistance, fatigue resistance, radiation resistance and excellent electrical properties. In most cases, it can replace metals, alloys, ceramics and other materials. These excellent properties enable PEEK parts to withstand harsh working conditions such as high-speed operation and high-precision processing in the semiconductor manufacturing process, maintain stable clamping force and shape accuracy, effectively prevent sliding or deformation of key components such as wafers, and resist corrosion from various common chemical substances in the semiconductor manufacturing process, extend the service life of parts, and reduce maintenance costs. However, the insulation of the PEEK matrix itself does not have antistatic properties. In processes such as wafer manufacturing, static electricity may cause damage to sensitive semiconductor components. Therefore, antistatic modification of PEEK is particularly important. Antistatic PEEK materials can effectively reduce the generation and accumulation of static electricity, thereby protecting wafers from static damage. Currently, the most common PEEK antistatic modification is to fill it with an inorganic conductive matrix, such as conductive carbon fiber, carbon nanotubes, graphene, conductive carbon black, metal fiber or powder, etc., and form a conductive network inside the PEEK matrix through melt blending, so that it has antistatic properties. There is also a method of directly coating the surface of the PEEK part with an organic antistatic agent coating to make it antistatic.

[0003] The existing method of blending PEEK with carbon fiber, metal fiber, etc., due to the anisotropy of the fibers, has obvious differences in orientation in the flow direction and vertical direction of the resin matrix processing, and the material is prone to warping, unevenness, and dimensional instability. Carbon nano and graphene, conductive carbon black are difficult to disperse in the traditional extrusion blending process due to their nanometer particle size and the high melt viscosity of PEEK, which can easily cause different conductivity at different positions and uneven color lines on the surface of the matrix. Moreover, the above-mentioned base materials have a black dyeing effect on PEEK after filling, and cannot meet the appearance requirements of white, etc. The method of directly coating the surface of PEEK parts with an organic antistatic agent coating can avoid the above problems, but because the coating itself is easy to fall off and age and lose during long-term use, it cannot meet the long-term antistatic effect of the material. Summary of the invention

[0004] The purpose of the present invention is to provide a method for preparing a polyetheretherketone composite material with high dimensional stability and antistatic properties, which adopts the method of filling and blending PEEK with conductive titanium dioxide and metal sulfide, and improves the warpage of the matrix by utilizing the good isotropic characteristics of the spherical morphology of titanium dioxide, and titanium dioxide has a whitening effect, which is suitable for the appearance requirements of white parts. At the same time, the wear-resistant effect of metal sulfide is utilized to give the material better wear resistance.

[0005] To achieve the above object, the present invention provides the following technical solutions.

[0006] The present application discloses a method for preparing a polyetheretherketone composite material with high dimensional stability and antistatic properties, which comprises the following steps in sequence:

[0007] S1 prepares the following raw materials by mass: 50-80 parts of polyetheretherketone, 10-30 parts of conductive titanium dioxide, 3-20 parts of metal sulfide, and 0.1-10 parts of processing aid;

[0008] S2: after the polyetheretherketone and the processing aid are mixed in a rotary mixer in proportion, they are fed into the main feed port of the twin-screw extruder, and the conductive titanium dioxide and the metal sulfide are fed into the side feed port of the extruder through a feeder to perform melt mixing, extrusion and granulation;

[0009] In step S3, the rotary mixer in step S2 has a rotation speed of 60-120 rpm, a mixing time of 5-10 min, an output of the twin-screw extruder of 100-200 Kg / h, a rotation speed of 200-400 rpm, a barrel temperature of 380±20°C, a head temperature of 370±10°C, and a vacuum section extraction pressure of -0.08±0.02 MPa.

[0010] Preferably, in the method for preparing the above-mentioned high dimensional stability and antistatic polyetheretherketone composite material, the polyetheretherketone has a melt flow rate of 10 to 100 g / 10 min and a powdery appearance.

[0011] Preferably, in the above-mentioned method for preparing the high dimensional stability and antistatic polyetheretherketone composite material, the conductive titanium dioxide is spherical rutile titanium dioxide whose surface is doped with tin and antimony elements, the powder particle size D50 is 0.2-0.3 μm, and the powder impedance is 1-30 Ω·m.

[0012] Preferably, in the above method for preparing the high dimensional stability and antistatic polyetheretherketone composite material, the processing aid includes one or more of silicone powder, polytetrafluoroethylene, and inorganic phosphate.

[0013] The present invention adopts the method of filling and blending PEEK with conductive titanium dioxide and metal sulfide, and improves the warpage of the matrix by utilizing the good isotropic characteristics of the spherical morphology of titanium dioxide, and the titanium dioxide has a whitening effect, which is suitable for the appearance requirements of white parts. At the same time, the wear resistance of metal sulfide is utilized to give the material better wear resistance. DETAILED DESCRIPTION

[0014] The technical solutions in the embodiments of the present invention are described in detail below. Obviously, the described embodiments are only 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.

[0015] Example 1: After polyetheretherketone (75 parts) and silicone powder (2 parts) are mixed in a rotary mixer in proportion, they are fed from the main feed port of a twin-screw extruder, and conductive titanium dioxide (20 parts) and molybdenum disulfide (3 parts) are fed from the side feed port of the extruder via a feeder, and melt-mixed extrusion granulation is performed. The rotary mixer used has a rotation speed of 100 rpm and a mixing time of 10 min. The twin-screw extruder has an output of 120 kg / h, a rotation speed of 200 rpm, a barrel temperature of 380°C, a head temperature of 370°C, and a vacuum section extraction pressure of -0.08 MPa.

[0016] Example 2: After polyetheretherketone (70 parts) and polytetrafluoroethylene (5 parts) are mixed in a rotary mixer in proportion, they are fed from the main feed port of a twin-screw extruder, and conductive titanium dioxide (20 parts) and molybdenum disulfide (5 parts) are fed from the side feed port of the extruder via a feeder, and melt-mixed extrusion granulation is performed. The rotary mixer used has a rotation speed of 100 rpm and a mixing time of 10 min. The twin-screw extruder has an output of 100 Kg / h, a rotation speed of 200 rpm, a barrel temperature of 380°C, a head temperature of 370°C, and a vacuum section extraction pressure of -0.08 MPa.

[0017] The composite material prepared according to the present invention has the following properties: the antistatic performance indexes all reach the typical comparative example (polyetheretherketone / 5% conductive carbon black), and a white appearance is achieved, and the isotropy and wear resistance are greatly improved.

[0018]

[0019] This implementation mode is only an exemplary description of this patent and does not limit its protection scope. Personnel in this field may also make partial changes to it. As long as it does not exceed the spirit of this patent, it shall be regarded as an equivalent replacement of this patent and shall be within the protection scope of this patent.

Claims

1. A method for preparing a polyetheretherketone composite material with high dimensional stability and antistatic properties, characterized in that: The steps are as follows: S1 prepares the following raw materials by mass: 50-80 parts of polyetheretherketone, 10-30 parts of conductive titanium dioxide, 3-20 parts of metal sulfide, and 0.1-10 parts of processing aid; S2: after the polyetheretherketone and the processing aid are mixed in a rotary mixer in proportion, they are fed into the main feed port of the twin-screw extruder, and the conductive titanium dioxide and the metal sulfide are fed into the side feed port of the extruder through a feeder to perform melt mixing, extrusion and granulation; In step S3, the rotary mixer in step S2 has a rotation speed of 60-120 rpm, a mixing time of 5-10 min, an output of the twin-screw extruder of 100-200 Kg / h, a rotation speed of 200-400 rpm, a barrel temperature of 380±20°C, a head temperature of 370±10°C, and a vacuum section extraction pressure of -0.08±0.02 MPa.

2. The method for preparing the high dimensional stability and antistatic polyetheretherketone composite material according to claim 1, characterized in that: The polyetheretherketone has a melt flow rate of 10 to 100 g / 10 min and a powdery appearance.

3. The method for preparing the high dimensional stability and antistatic polyetheretherketone composite material according to claim 1, characterized in that: The conductive titanium dioxide is a spherical rutile titanium dioxide with a surface doped with tin and antimony elements, a powder particle size D50 of 0.2 to 0.3 μm, and a powder impedance of 1 to 30 Ω·m.

4. The method for preparing the high dimensional stability and antistatic polyetheretherketone composite material according to claim 1, characterized in that: The processing aid includes one or more of silicone powder, polytetrafluoroethylene, and inorganic phosphate.

Images