CN117362971A - Antistatic composite material and preparation method and application thereof - Google Patents

Abstract

The application discloses an antistatic composite material, a preparation method and application thereof, and relates to the technical field of composite materials. The antistatic composite material comprises the following components in parts by weight: 80-100 parts of matrix resin; 1-5 parts of matrix dispersing agent; 20-40 parts of modified carbon nano tube master batch; the modified carbon nano tube master batch comprises a first resin, a carbon nano tube grafted spherical particle compound and a first dispersing agent; wherein the melting temperature of the first resin is 30-60 ℃ higher than the melting temperature of the matrix resin, and the melting processing temperature in the preparation process of the antistatic composite material is 10-20 ℃ lower than the melting temperature of the first resin. Therefore, the carbon nano tube can be uniformly dispersed in the antistatic composite material and can form a conductive network path, so that the antistatic composite material has good performance.

Description

Antistatic composite material and preparation method and application thereof

Technical Field

The application belongs to the technical field of composite materials, and particularly relates to an antistatic composite material, and a preparation method and application thereof.

Background

With the development of technology, in the existing antistatic composite material using carbon nanotubes as a conductive agent, because the specific surface area of the carbon nanotubes is large and the carbon nanotubes are easy to agglomerate, the carbon nanotubes are difficult to uniformly disperse in a resin material, so that small particles are easy to form on the surface of a product prepared from the antistatic composite material, and the surface performance, antistatic performance and the like of the product are affected. In addition, the existing antistatic composite material is prepared by firstly carrying out screw melt extrusion granulation, then forming material particles through a forming process, and the problem of shearing dispersion exists in the screw extrusion granulation process, so that carbon nanotubes are difficult to disperse uniformly in a resin material.

Accordingly, there is a need to provide an antistatic composite material to solve the above problems.

Disclosure of Invention

The invention aims to overcome the defects in the prior art and provide an antistatic composite material, a preparation method and application thereof, wherein carbon nanotubes in the antistatic composite material can be uniformly dispersed and can form a conductive network path, so that the antistatic composite material has better performance.

In order to achieve the above object, according to a first aspect of the present application, there is provided an antistatic composite material comprising, in parts by weight:

80-100 parts of matrix resin;

1-5 parts of matrix dispersing agent;

20-40 parts of modified carbon nano tube master batch;

the modified carbon nano tube master batch comprises a first resin, a carbon nano tube grafted spherical particle compound and a first dispersing agent;

wherein the melting temperature of the first resin is 30-60 ℃ higher than the melting temperature of the matrix resin, and the melting processing temperature in the preparation process of the antistatic composite material is 10-20 ℃ lower than the melting temperature of the first resin.

Further, the modified carbon nanotube master batch is prepared from the following raw materials in parts by weight:

50-80 parts of a first resin;

10-20 parts of carbon nano tubes;

5-20 parts of spherical particles;

1-5 parts of a first dispersing agent.

Further, epoxy groups are grafted on the surfaces of the spherical particles, amino groups are grafted on the surfaces of the carbon nanotubes, and the epoxy groups and the amino groups undergo bonding reaction so that the carbon nanotubes are grafted on the surfaces of the spherical particles.

Further, the spherical particles include spherical particles grafted with an epoxy siloxane coupling agent, and the carbon nanotubes include carbon nanotubes grafted with an aminosiloxane coupling agent.

Further, the matrix resin comprises a thermoplastic resin comprising at least one of polyethylene, polypropylene, polystyrene, polycarbonate, polyamide, polyoxymethylene, polyphenylene oxide, ABS;

and/or the number of the groups of groups,

the first resin comprises at least one of polyvinyl chloride, polyethylene terephthalate, polycarbonate, polytetrafluoroethylene, polyether and aromatic heterocyclic polymer.

Further, the pipe diameter range of the carbon nano-pipe comprises 1.0-6.0nm;

and/or the number of the groups of groups,

the length range of the carbon nano tube comprises 10-100 mu m;

and/or the number of the groups of groups,

the length-diameter ratio of the carbon nano tube ranges from 5000:1 to 120000:1;

and/or the number of the groups of groups,

the specific surface area of the carbon nano tube ranges from 800 m to 1200m ² /g；

And/or the number of the groups of groups,

raman spectrum I of the carbon nanotubes _D /I _G 0.3-0.7;

and/or the number of the groups of groups,

the powder resistivity range of the carbon nano tube comprises 0.1-5mΩ cm.

In a second aspect of the present application, a method for preparing the antistatic composite material is provided, including the following steps:

reacting the carbon nano tube with spherical particles in an alkaline solution to obtain a carbon nano tube grafted spherical particle compound;

uniformly mixing the carbon nanotube grafted spherical particle compound, the first resin and the first dispersing agent, and then treating to obtain modified carbon nanotube master batch;

and uniformly mixing the modified carbon nanotube master batch with matrix resin and matrix dispersing agent, and then treating to obtain the antistatic composite material.

Further, the reacting the carbon nanotubes with the spherical particles in an alkaline solution to obtain a carbon nanotube grafted spherical particle composite comprises:

and (3) reacting the carbon nano tube grafted with the amino group with the glass bead grafted with the epoxy group in the alkaline solution to obtain the carbon nano tube grafted glass bead compound.

Further, the step of uniformly mixing the carbon nanotube-grafted spherical particle composite with a first resin and a first dispersant and then treating the mixture to obtain a modified carbon nanotube master batch comprises the following steps:

Uniformly mixing the carbon nanotube-grafted spherical particle compound, first resin and a first dispersing agent, and then carrying out melt extrusion granulation to obtain the modified carbon nanotube master batch; wherein, the melt extrusion granulation at least comprises a melt plasticizing section and a mixing homogenizing section.

Further, the step of uniformly mixing the modified carbon nanotube master batch with matrix resin and matrix dispersant and then processing to obtain the antistatic composite material comprises the following steps:

uniformly mixing the modified carbon nanotube master batch with the matrix resin and the matrix dispersing agent, and then performing screw extrusion granulation; wherein, screw extrusion granulation adopts the screw combination as follows: the screw combination sequence of the conveying shearing section is 56/56, 96/96, 96/48, 72/72, 64/64, 45 DEG/5/56, 60 DEG/4/44, 90 DEG/5/56; the screw combination sequence of the melt plasticizing section is K30 degrees/5/56, K45 degrees/4/56, K60 degrees/5/44, 44/44, K45 degrees/6/56, K60 degrees/5/44, 44/44, K60 degrees/4/56, K90 degrees/5/56, 44/44, K60 degrees/4/44, K60 degrees/5/56, K90 degrees/4/44, 44/22L; the screw combination sequence of the mixing homogenization sections is K60 degrees/5/56, K90 degrees/5/56, 72/72, C18, 44/44, K60 degrees/5/56, K90 degrees/5/56, K60 degrees/5/44L, 44/44, C18, 72/72, K60 degrees/5/56, K90 degrees/5/56; the screw combination sequence of the vacuum exhaust section is 44/44L, 72/72, 96/96 and 72/72; the screw combination sequence of the extrusion build-up section is 72/72, 56/56, 72/72, 44/44.

Compared with the prior art, the application has the following technical effects:

according to the antistatic composite material, the carbon nanotubes are grafted on the surfaces of the spherical particles and are dispersed in the matrix resin, so that the agglomeration of the carbon nanotubes in the modified carbon nanotube master batch is effectively reduced, a better uniform dispersion effect is achieved, and meanwhile, the carbon nanotubes are outwards dispersed on the spherical particles and can be better lapped to form a conductive network path; in addition, by setting the melting temperature of the first resin to be 30-60 ℃ higher than the melting temperature of the matrix resin, the melting processing temperature in the preparation process of the antistatic composite material can be 10-20 ℃ lower than the melting temperature of the first resin, so that at the extrusion temperature, the matrix resin is melted and the modified carbon nanotube master batch is not completely melted, a softened state is formed, the degree of freedom of the carbon nanotube is reduced compared with that in the melted state, and the agglomeration of the carbon nanotube is further reduced.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings that are needed in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present application, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a process flow diagram of a preparation process of an antistatic composite material according to an embodiment of the present application;

FIG. 2 is a flow chart of another process for preparing an antistatic composite material according to an embodiment of the present application;

FIG. 3 is a flow chart of a process for preparing an antistatic composite material according to an embodiment of the present application;

fig. 4 is a flowchart of a preparation process of another antistatic composite material according to an embodiment of the present application.

Detailed Description

In order to make the technical problems, technical schemes and beneficial effects to be solved by the present application more clear, the present application is further described in detail below with reference to the embodiments. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the present application.

In this application, the term "and/or" describes an association relationship of an association object, which means that there may be three relationships, for example, a and/or B may mean: a alone, a and B together, and B alone. Wherein A, B may be singular or plural. The character "/" generally indicates that the context-dependent object is an "or" relationship.

In the present application, "at least one" means one or more, and "a plurality" means two or more. "at least one of" or the like means any combination of these items, including any combination of single item(s) or plural items(s). For example, "at least one (a), b or c)", or "at least one (a, b and c)", may each represent: a, b, c, a-b (i.e., a and b), a-c, b-c or a-b-c, wherein a, b, c may be single or multiple, respectively.

It should be understood that, in various embodiments of the present application, the sequence number of each process does not mean that the execution sequence is sequential, and some or all of the steps may be executed in parallel or sequentially, where the execution sequence of each process should be determined by its functions and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

The terminology used in the embodiments of the application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used in this application and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

The weights of the relevant components mentioned in the embodiments of the present application may refer not only to specific contents of the components, but also to the proportional relationship between the weights of the components, and thus, any ratio of the contents of the relevant components according to the embodiments of the present application may be enlarged or reduced within the scope disclosed in the embodiments of the present application. Specifically, the mass in the specification of the embodiment of the present application may be a known mass unit such as μ g, mg, g, kg.

The terms "first," "second," and the like are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or an implicit indication of the number of technical features indicated. For example, a first XX may also be referred to as a second XX, and similarly, a second XX may also be referred to as a first XX, without departing from the scope of embodiments of the present application. Thus, a feature defining "a first", "a second", etc. may include one or more of the feature, either explicitly or implicitly.

In a first aspect, embodiments of the present application provide an antistatic composite material, the antistatic composite material comprising, in parts by weight: 80-100 parts of matrix resin; 1-5 parts of matrix dispersing agent; 20-40 parts of modified carbon nano tube master batch; the modified carbon nano tube master batch comprises a first resin, a carbon nano tube grafted spherical particle compound and a first dispersing agent; wherein the melting temperature of the first resin is 30-60 ℃ higher than the melting temperature of the matrix resin, and the melting processing temperature in the preparation process of the antistatic composite material is 10-20 ℃ lower than the melting temperature of the first resin.

The melting temperature of the first resin above the melting temperature of the matrix resin is not particularly limited, and the melting temperature of the first resin above the melting temperature of the matrix resin may be, for example, 30 ℃, 35 ℃, 40 ℃, 45 ℃, 50 ℃, 60 ℃, or the like.

The above-mentioned melt processing temperature in the process of preparing the antistatic composite material is not particularly limited, and the melt processing temperature in the process of preparing the antistatic composite material may be 10 ℃, 12 ℃, 13 ℃, 14 ℃, 15 ℃, 20 ℃ or the like, by way of example.

In one or more embodiments, the matrix resin herein may include a thermoplastic resin such as Polyethylene (PE), polypropylene (PP), polystyrene (PS), polycarbonate (PC), polyamide (PA), polyoxymethylene (POM), polyphenylene oxide (PPO), ABS, impact polystyrene (HIPS), etc. The first resin in the present application may include polyvinyl chloride (PVC), polyethylene terephthalate (PET), polycarbonate (PC), polytetrafluoroethylene (PTFE), polyether polyesters, aromatic heterocyclic polymers, polybutylene terephthalate (PBT), ABS, and the like. Here, the matrix resin may be selected to correspond to the first resin, for example, when the matrix resin is selected to be PE, PP, PS, the first resin may be selected to be PVC, PET, PC accordingly, as long as the melting temperature of the first resin is higher than the melting temperature of the matrix resin by 30 to 60 ℃.

In one or more embodiments, the melting temperature range of the matrix resin may include 100-250 ℃, and exemplary melting temperatures of the matrix resin may be 110 ℃, 150 ℃, 180 ℃, 200 ℃, 210 ℃, 220 ℃, 230 ℃, 240 ℃, 250 ℃, or the like.

In one or more embodiments, the melting temperature range of the first resin may include 150-310 ℃, and exemplary melting temperature ranges of the matrix resin may be 160 ℃, 200 ℃, 230 ℃, 260 ℃, 270 ℃, 290 ℃, 300 ℃, 310 ℃, or the like.

In one or more embodiments, the melt processing temperature during the preparation of the antistatic composite material may range from 140 to 290 ℃, and illustratively, the melt processing temperature during the preparation of the antistatic composite material may be 140 ℃, 160 ℃, 180 ℃, 220 ℃, 240 ℃, 250 ℃, 270 ℃, 280 ℃, 290 ℃, or the like.

It should be noted that, in the antistatic composite material in the embodiment of the present application, other additives may be added as required, for example, a lubricant, an antioxidant, an inorganic filler, and the like may also be added to the antistatic composite material, which is not particularly limited herein.

The parts by weight of the above-mentioned matrix resin are not particularly limited, and exemplary parts by weight of the matrix resin may be 80 parts, 85 parts, 90 parts, 95 parts, 100 parts, or the like.

In one or more embodiments, the matrix dispersant, the first dispersant herein may include at least one of talc, mica powder, silicone powder, and the like.

The parts by weight of the above-mentioned matrix dispersant are not particularly limited, and the exemplary parts by weight of the matrix dispersant may be 1 part, 2 parts, 3 parts, 4 parts, 5 parts, or the like.

The parts by weight of the modified carbon nanotube master batch are not particularly limited, and exemplary parts by weight of the modified carbon nanotube master batch may be 20 parts, 25 parts, 30 parts, 35 parts, 40 parts, or the like.

Further, the modified carbon nanotube master batch comprises 15-30 parts by weight, specifically 15 parts, 18 parts, 20 parts, 25 parts or 30 parts by weight, etc.

In the application, the type of the spherical particles in the above-mentioned carbon nanotube grafted spherical particle composite is not particularly limited, and the spherical particles may include glass beads and the like, for example. Further, the spherical particles may include glass beads having epoxy groups grafted on the surface, and the like. Further, the spherical particles can be glass beads with epoxy groups grafted on the surfaces after the glass beads are modified by an epoxy siloxane coupling agent. Of course, not limited thereto, and the actual application is in particular.

The spherical particles have the advantages that: the specific surface area of the spherical particles is large, so that the grafting rate of the carbon nano tubes on the surfaces of the spherical particles can be improved; meanwhile, the carbon nano tube grafted on the surface of the spherical particle has good divergence, and is easier to lap even under the condition of low grafting rate, so that a conductive path is formed.

The parts by weight of the above spherical particles are not particularly limited, and exemplary parts by weight of the spherical particles may include 5 to 20 parts. Specifically, the parts of the spherical particles may be 5 parts, 7 parts, 10 parts, 15 parts, 20 parts, or the like.

The parts by weight of the above carbon nanotubes are not particularly limited, and exemplary ranges of the parts by weight of the carbon nanotubes may include 10 to 20 parts. Specifically, the number of carbon nanotubes may be 10 parts, 12 parts, 15 parts, 18 parts, 20 parts, or the like.

The parts by weight of the above-mentioned first resin are not particularly limited, and exemplary ranges of the parts by weight of the first resin may include 50 to 80 parts. Specifically, the parts of the first resin may be 50 parts, 55 parts, 60 parts, 70% or 80 parts, or the like.

The parts by weight of the above-mentioned first dispersant are not particularly limited, and exemplary ranges of the parts by weight of the first dispersant may include 1 to 5 parts. Specifically, the parts of the first dispersant may be 1 part, 2 parts, 3 parts, 4 parts, or parts, etc.

In practical applications, the tube diameters of the carbon nanotubes are not particularly limited, and exemplary tube diameters of the carbon nanotubes may range from 1.0nm to 6.0nm. Specifically, the diameter of the carbon nanotubes may be 1.0nm, 2.0nm, 3.0nm, 4.0nm, 5.0nm, 6.0nm, or the like.

The tube length of the above-mentioned carbon nanotubes is not particularly limited, and exemplary tube lengths of the carbon nanotubes may include 10 to 100 μm. Specifically, the tube length of the carbon nanotube may be 10 μm, 30 μm, 50 μm, 60 μm, 80 μm, 100 μm, or the like.

The aspect ratio of the carbon nanotubes is not particularly limited, and exemplary aspect ratios of the carbon nanotubes may range from 5000:1 to 120000:1. Specifically, the aspect ratio of the carbon nanotubes may be 5000:1, 6000:1, 7000:1, 9000:1, 10000:1, 12000:1, or the like.

The specific surface area of the carbon nanotubes is not particularly limited, and exemplary specific surface areas of the carbon nanotubes may range from 800 to 1200m ² And/g. Specifically, the specific surface area of the carbon nanotubes may be 800m ² /g、900m ² /g、1000m ² /g、1100m ² /g or 1200m ² /g, etc.

Raman spectrum I for the above carbon nanotubes _D /I _G Without being particularly limited, exemplary Raman spectra I of carbon nanotubes _D /I _G May be 0.3 to 0.7. Specifically, the raman spectrum I of the carbon nanotubes _D /I _G May be 0.3, 0.4, 0.5, 0.6, 0.7, etc.

The powder resistivity of the carbon nanotubes is not particularly limited, and exemplary ranges of the powder resistivity of the carbon nanotubes may include 0.1-5mΩ·cm. Specifically, the powder resistivity of the carbon nanotubes may be 0.1mΩ·cm, 1mΩ·cm, 2mΩ·cm, 3mΩ·cm, 4mΩ·cm, 5mΩ·cm, or the like.

According to the antistatic composite material provided by the embodiment of the application, on one hand, the carbon nanotubes are grafted on the surfaces of the spherical particles and dispersed in the matrix resin, so that the agglomeration of the carbon nanotubes in the modified carbon nanotube master batch is effectively reduced, a better uniform dispersing effect is achieved, and meanwhile, the carbon nanotubes are outwards dispersed on the spherical particles and can be better lapped to form a conductive network path; on the other hand, by setting the melting temperature of the first resin to be 30-60 ℃ higher than the melting temperature of the matrix resin, the melting processing temperature in the preparation process of the antistatic composite material can be 10-20 ℃ lower than the melting temperature of the first resin, so that at the extrusion temperature, the matrix resin is melted and the modified carbon nanotube master batch is not completely melted, a softened state is formed, the degree of freedom of the carbon nanotube is reduced compared with that in the melted state, and the agglomeration of the carbon nanotube is further reduced. Therefore, the antistatic composite material has better performance.

Further, epoxy groups are grafted on the surfaces of the spherical particles, amino groups are grafted on the surfaces of the carbon nanotubes, and the epoxy groups and the amino groups undergo bonding reaction so that the carbon nanotubes are grafted on the surfaces of the spherical particles.

The source of the epoxy group is not particularly limited, and the epoxy group may be derived from an epoxysiloxane coupling agent by way of example.

The source of the above amino group is not particularly limited, and exemplified amino groups may be derived from aminosilicone coupling agents. The type of aminosilicone coupling agent is not particularly limited herein, and exemplary aminosilicone coupling agents may include gamma-aminopropyl methyldiethoxysilane, and the like.

Further, the spherical particles may include spherical particles grafted with an epoxy siloxane coupling agent, and the carbon nanotubes may include carbon nanotubes grafted with an aminosiloxane coupling agent.

According to the antistatic composite material provided by the embodiment of the application, the amino group and the epoxy group are easy to react, so that the obtained yield is high, more carbon nanotubes can be grafted onto the particles, and the carbon nanotubes have better dispersibility.

In a second aspect, embodiments of the present application provide a method for preparing an antistatic composite material.

As shown in fig. 1 to 4, the preparation method of the antistatic composite material comprises the following steps:

s1, reacting the carbon nano tube with spherical particles in an alkaline solution to obtain a carbon nano tube-connected spherical particle compound.

The temperature at which the above-mentioned carbon nanotubes react with the spherical particles in the alkaline solution is not particularly limited, and exemplary temperature ranges for the reaction of the carbon nanotubes with the spherical particles in the alkaline solution may include 30 to 50 ℃. Specifically, the reaction temperature of the carbon nanotubes and the spherical particles in the alkaline solution may be 30 ℃, 35 ℃, 40 ℃, 45 ℃, 50 ℃ or the like.

The PH value (PH) of the reaction of the carbon nanotubes and the spherical particles in the alkaline solution is not particularly limited, and exemplary PH ranges of the reaction of the carbon nanotubes and the spherical particles in the alkaline solution may include 8 to 10. Specifically, the pH at which the carbon nanotubes react with the spherical particles in an alkaline solution may be 8, 8.5, 9, 9.5, 10, or the like.

The time for the reaction of the above-mentioned carbon nanotubes with the spherical particles in the alkaline solution is not particularly limited, and exemplary time ranges for the reaction of the carbon nanotubes with the spherical particles in the alkaline solution may include 3 to 5 hours. Specifically, the reaction time of the carbon nanotubes and the spherical particles in the alkaline solution may be 3 hours, 3.5 hours, 4 hours, 4.5 hours, 5 hours, or the like.

Further, in the step S1, the reaction of the carbon nanotubes with the spherical particles in the alkaline solution to obtain the carbon nanotube-grafted spherical particle composite includes:

S11, reacting the carbon nano tube grafted with the amino group with the glass bead grafted with the epoxy group in an alkaline solution to obtain the carbon nano tube grafted glass bead compound.

Wherein the glass beads are grafted by epoxy siloxane coupling agent; the carbon nanotubes are grafted with aminosiloxane coupling agent.

S2, uniformly mixing the carbon nano tube grafted spherical particle compound, the first resin and the first dispersing agent, and then treating to obtain the modified carbon nano tube master batch.

Further, in the step S2, the process is performed after uniformly mixing the carbon nanotube grafted spherical particle composite with the first resin and the first dispersant, so as to obtain a modified carbon nanotube master batch, which includes:

and S20, uniformly mixing the carbon nano tube grafted glass microsphere compound with the first resin and the first dispersing agent, and then treating to obtain the modified carbon nano tube master batch.

Further, in the step S20, the step of uniformly mixing the carbon nanotube grafted glass bead composite with the first resin and the first dispersant, and then performing a treatment to obtain a modified carbon nanotube master batch includes:

s21, uniformly mixing the carbon nano tube grafted glass microsphere compound with the first resin and the first dispersing agent, and performing melt extrusion granulation to obtain the modified carbon nano tube master batch.

Wherein, the melt extrusion granulation may comprise: the device comprises a conveying and shearing section (also called a feeding and conveying section), a melting and plasticizing section, a mixing and homogenizing section, a vacuum exhausting section and an extrusion and pressure building section.

S3, uniformly mixing the modified carbon nanotube master batch, matrix resin and matrix dispersing agent, and then treating to obtain the antistatic composite material.

Step S3, uniformly mixing the modified carbon nanotube master batch with matrix resin and matrix dispersing agent, and then treating to obtain the antistatic composite material, wherein the step comprises the following steps of:

s31, uniformly mixing the modified carbon nanotube master batch, matrix resin and matrix dispersing agent, and then carrying out screw extrusion granulation to obtain the antistatic composite material.

Wherein, screw extrusion granulation adopts the following screw combination: the screw combination sequence of the conveying shearing section is 56/56, 96/96, 96/48, 72/72, 64/64, 45 DEG/5/56, 60 DEG/4/44, 90 DEG/5/56; the screw combination sequence of the melt plasticizing section is K30 degrees/5/56, K45 degrees/4/56, K60 degrees/5/44, 44/44, K45 degrees/6/56, K60 degrees/5/44, 44/44, K60 degrees/4/56, K90 degrees/5/56, 44/44, K60 degrees/4/44, K60 degrees/5/56, K90 degrees/4/44, 44/22L; the screw combination sequence of the mixing homogenization sections is K60 degrees/5/56, K90 degrees/5/56, 72/72, C18, 44/44, K60 degrees/5/56, K90 degrees/5/56, K60 degrees/5/44L, 44/44, C18, 72/72, K60 degrees/5/56, K90 degrees/5/56; the screw combination sequence of the vacuum exhaust section is 44/44L, 72/72, 96/96 and 72/72; the screw combination sequence of the extrusion build-up section is 72/72, 56/56, 72/72, 44/44.

In application, the conveying and shearing section has a shearing function. Therefore, when the matrix resin and the modified carbon nanotube master batch are fed from the main feeding port, the modified carbon nanotube master batch and the matrix resin can be fed according to an accurate proportion, and the modified carbon nanotube master batch can be mixed in the matrix resin more uniformly from the beginning of feeding, so that the materials are melted and plasticized in advance, the processing fluidity is improved, the screw extrusion process is adapted and matched, and the industrial production of the carbon nanotube antistatic composite material is improved.

Specific process equipment, parameters, etc. of the melt extrusion granulation in the examples of the present application are given below.

The apparatus, apparatus configuration, apparatus parameters, etc. for the above-mentioned melt extrusion granulation are not particularly limited, and the melt extrusion granulation may be performed by a screw extruder as an example. Specifically, melt extrusion granulation may be performed by a twin screw extruder.

In practice, the twin screw extruder may include a feed conveying section (also known as a conveying shear section), a melt plasticizing section, a compounding homogenizing section, a vacuum venting section, and an extrusion build-up section.

Wherein the screw combination order of the conveying and shearing sections may be 56/56, 96/96, 96/48, 72/72, 64/64, 45 °/5/56, 60 °/4/44 and 90 °/5/56; the screw combination sequence of the melt plasticizing stage may be K30/5/56, K45/4/56, K60/5/44, 44/44, K45/6/56, K60/5/44, 44/44, K60/4/56, K90/5/56, 44/44, K60/4/44, K60/5/56, K90/4/44 and 44/22L; the screw combination sequence of the mixing homogenization sections can be K60/5/56, K90/5/56, 72/72, C18, 44/44, K60/5/56, K90/5/56, K60/5/44L, 44/44, C18, 72/72, K60/5/56 and K90/5/56; the screw combination sequence of the vacuum exhaust section can be 44/44L, 72/72, 96/96 and 72/72; the screw combination sequence of the extrusion build-up sections may be 72/72, 56/56, 72/72 and 44/44.

In the screw combination of the above twin screw extruder, there are flighted elements which can be divided into conveying elements, shearing elements and special elements (e.g., stretching elements, dispersing elements, tooth plates, transition pieces, etc.).

The representation and meaning of the different threaded elements are as follows:

1. the conveying element may consist of a lead and a length, with a division of a forward direction, which is indicated by only two digits, and a reverse direction, which is indicated by two digits followed by an "L". For example, in 56/56, the first "56" represents the lead (i.e., the axial length of the material that makes one turn around the thread) and the second "56" represents the length of the threaded element (i.e., the axial length of the threaded element). The usual elements of the transport block are 128/128, 96/96, 72/72, 64/64, 56/56, 44/44, 48/48, 32/32, 22/22, 96/48, 72/36, 44/22L and 22/11L.

2. The shearing element is formed by kneading a plurality of shearing single sheets, the number of the shearing single sheets can be in a range of 4-7 sheets, the thickness of the single sheets is different, and different shearing single sheet kneading types can be selected according to different requirements. Specifically, the thicker the thickness of the sheared single sheet is, the stronger the distribution capacity is, and the thinner the thickness of the sheared single sheet is, the stronger the distribution capacity is; the larger the angle between the sheared pieces, the stronger the shearing capability; the shear blade has a forward and a reverse division. For example, a forward shear slice may be expressed as K angle/number of slices/element length, and a reverse shear slice may be expressed as K angle/number of slices/element length L. Illustratively, in K90/5/56L, 90 represents the angle at which the shear sheets are kneaded is 90 degrees, 5 represents the number of sheets of the shear sheets, 56 represents the length of the shear sheets, and L represents the left direction.

3. In a particular shear element, the stretching element may, by way of example, act as a dispersing, distributing element, typically used in the back end homogenizing zone of the screw, expressed as lead/length L, e.g., 78/78L for a reverse stretching element having a lead of 78 and a length of 78. Illustratively, the toothed disc is mainly used for dispersion, generally in the homogenization section at the rear end of the screw, denoted by C thickness, for example, C18 represents a toothed disc with a thickness of 18 mm.

The modified carbon nanotube master batch, the matrix resin, the matrix dispersant, the carbon nanotubes and the like in the embodiments of the present application may refer to the above embodiments, and are not described herein again.

According to the preparation method of the antistatic composite material, extrusion granulation is carried out through the double-screw extruder, and then particles are molded through the molding process, in the process, as the dispersibility of the carbon nano tubes in the antistatic composite material is greatly influenced by the screw combination of the melting plasticizing section and the mixing homogenizing section in the double-screw extruder, the melting extrusion temperature, the screw combination and the like are optimized according to the dispersion effect of the modified carbon nano tube master batch, and the formed shearing-stretching field can enable the modified carbon nano tube master batch to be well dispersed in matrix resin and also can not form a sea island structure with isolated conductive paths; when the combination of the strong shearing element and the strong dispersing element is used in the melting plasticizing section and the mixing homogenizing section of the extruder screw, the materials are fully melted and plasticized after entering the extruder, and then fully mixed and dispersed by the rear-end strong dispersing element, so that the melting fluidity of matrix resin in the whole processing process is good, the modified carbon nano tube master batch which is not fully melted can be slowly elongated and thinned and mutually lapped, the lines are mutually lapped and penetrated, three-dimensional net-shaped uniform distribution in the matrix resin can be formed, the carbon nano tubes can also form good conductive paths, the flatness and smoothness of the product surface are effectively improved, and the pockmark particles on the product surface are reduced; in addition, the matrix resin and the modified carbon nano tube master batch can be fed from a main feeding port according to an accurate proportion and uniformly mixed from the beginning, so that the method is suitable for and matched with the existing screw extrusion process, and the industrial production of the carbon nano tube antistatic composite material is improved.

A specific preparation method of the modified carbon nanotube master batch is described below.

The preparation method of the modified carbon nano tube master batch comprises the following steps:

step 1, firstly, modifying glass beads by an epoxy siloxane coupling agent (enabling epoxy groups to be grafted on the surfaces of the glass beads), and then, reacting the glass beads with an amino siloxane coupling agent (the amino siloxane coupling agent is gamma-aminopropyl methyl diethoxy silane, for example, in the process, amino groups and epoxy groups are easy to react, the yield is high, and more carbon nanotubes can be grafted on the glass beads) in an alkaline solution (the temperature is 40 ℃, the PH is 8-10, and the time is 4 hours), so that the carbon nanotube grafted glass bead compound is obtained.

And 2, uniformly mixing 15-30% of the carbon nanotube-connected glass microsphere compound with matrix resin and 1-5% of matrix dispersing agent (talcum powder, mica powder and silicone powder), and carrying out melt extrusion granulation to obtain the modified carbon nanotube master batch.

The carbon nanotube grafted glass microsphere compound provided by the embodiment of the application has mild generation conditions and high carbon nanotube load; meanwhile, the carbon nano tube is grafted on the glass bead, so that the aggregation of the carbon nano tube in the carbon nano tube grafted glass bead compound can be reduced, the uniform dispersion effect is achieved, and the carbon nano tube is outwards dispersed on the spherical particles, so that the carbon nano tube can be better lapped to form a conductive network path; and the carbon nanotube grafted glass microsphere compound, the matrix resin and the matrix dispersing agent are subjected to melt extrusion granulation, and then the particles are molded by a molding process, so that the method is simple and easy to realize.

The following examples illustrate the preparation and use of the antistatic composite materials of the examples of the present application and the antistatic composite materials of the comparative examples.

Antistatic composite material and preparation method thereof of the application are as follows:

example 1

1. Preparation of modified carbon nano tube master batch:

(11) Pretreating glass beads: and (3) washing the glass beads with alkali, then washing with acid, and washing with water until the washing liquid is neutral, so that the surfaces of the glass beads have more hydroxyl groups.

(12) Weighing a certain mass of 3- (2, 3-glycidoxy) propyl trimethoxy silane (A-187), and dissolving the 3- (2, 3-glycidoxy) propyl trimethoxy silane in a mixed solution of water and ethanol (volume ratio is 1:3) (the mass concentration of the silane coupling agent is1 wt%) followed by acetic acid (CH) ₃ COOH) solution to adjust the pH of the solution to a range of 4-6. Adding the treated glass beads, stirring at 80 ℃ for reaction for 20-40min, filtering, washing and drying.

(13) Adding gamma-aminopropyl triethoxysilane (KH 550) (the mass concentration of the silane coupling agent is 3 wt%) into deionized water and ethanol (volume ratio is 1:3) as mixed solvents under stirring, adjusting the pH value to 5.0-6.0 by adopting hydrochloric acid (HCl), adding carbon nano tube powder, stirring and reacting at 60 ℃ for 7h, filtering, washing to neutrality, and drying at high temperature of 125 ℃ to obtain the carbon nano tube modified by the aminosilane coupling agent.

(14) And (3) mixing the substances obtained in the steps (12) and (13) into carbon nano tubes according to the mass ratio: glass bead=5:1 was reacted in an alkaline solution (temperature 40 ℃, PH 8-10, time 4 h) to obtain a carbon nanotube-grafted glass bead composite.

(15) Uniformly mixing 20% of carbon nanotube grafted glass microsphere compound with 78% of PET resin and 2% of talcum powder dispersing agent, and performing melt extrusion granulation to obtain modified carbon nanotube master batch.

2. Preparation of antistatic composite material:

taking the base resin as PC and the melting temperature as 230 ℃ as an example, the extrusion process can comprise the following steps:

(16) 80 parts of matrix resin PC, 30 parts of modified carbon nanotube master batch (the first resin is PET resin with the melting temperature of 260 ℃) and 1 part of silicone powder dispersing agent are poured into a mixer, treated for 6min at the rotating speed of 200r/min, and stirred and mixed uniformly.

(17) The mixture was placed into the feed opening of the main feed of the twin-screw extruder, and the materials were melt-mixed by the twin-screw extruder (extrusion temperature was 250 ℃, and main machine rotation speed was 400 rpm).

(18) And drawing the melt obtained by melt mixing at a constant moving speed through a shaping die, cooling through a water tank, air-drying and granulating to obtain the antistatic PC composite material with the particle diameter of 2-3 mm.

In a twin screw extruder, the screw combinations of conveying shear segments may be in the order 56/56, 96/96, 96/48, 72/72, 64/64, 45 °/5/56, 60 °/4/44 and 90 °/5/56; the screw combination sequence of the melt plasticizing stage may be K30/5/56, K45/4/56, K60/5/44, 44/44, K45/6/56, K60/5/44, 44/44, K60/4/56, K90/5/56, 44/44, K60/4/44, K60/5/56, K90/4/44 and 44/22L; the screw combination sequence of the mixing homogenization sections can be K60/5/56, K90/5/56, 72/72, C18, 44/44, K60/5/56, K90/5/56, K60/5/44L, 44/44, C18, 72/72, K60/5/56 and K90/5/56; the screw combination sequence of the vacuum exhaust section can be 44/44L, 72/72, 96/96 and 72/72; the screw combination sequence of the extrusion build-up sections may be 72/72, 56/56, 72/72 and 44/44.

Example 2

1. Preparation of modified carbon nano tube master batch:

(21) Pretreating glass beads: and (3) washing the glass beads with alkali, then washing with acid, and washing with water until the washing liquid is neutral, so that the surfaces of the glass beads have more hydroxyl groups.

(22) 3- (2, 3-glycidoxy) propyl trimethoxy silane (A-187) with certain mass is weighed and dissolved in a mixed solution of water and ethanol (the volume ratio is 1:3) (the mass concentration of the silane coupling agent is 2wt percent), and then the pH value of the solution is regulated to be in the range of 4-6 by acetic acid solution. Adding the treated glass beads, stirring at 70 ℃ for reaction for 20-40min, filtering, washing and drying.

(23) Adding gamma-aminopropyl triethoxysilane (KH 550) (the mass concentration of the silane coupling agent is 3 wt%) into deionized water and ethanol (volume ratio is 1:3) as mixed solvents under stirring, adjusting the pH value to 5.0-6.0 by adopting hydrochloric acid, adding carbon nano tube powder, stirring at 60 ℃ for reaction for 8 hours, filtering, washing to neutrality, and drying at high temperature of 140 ℃ to obtain the carbon nano tube modified by the aminosilane coupling agent.

(24) And (3) mixing the substances obtained in the steps (22) and (23) into carbon nano tubes according to the mass ratio: glass beads=6:1 were reacted in an alkaline solution (temperature 40 ℃, PH 8-10, time 5 h) to obtain carbon nanotube-grafted glass bead composites.

(25) Uniformly mixing 30% of the carbon nanotube-based glass microsphere composite with 69% of PBT resin and 1% of mica powder dispersing agent, and performing melt extrusion granulation to obtain modified carbon nanotube master batch.

2. Preparation of antistatic composite material:

taking HIPS as a matrix resin and 180 ℃ as an example, the extrusion process can include the following steps:

(26) 100 parts of matrix resin HIPS, 40 parts of modified carbon nanotube master batch (the first resin is PBT resin, the melting temperature is 230 ℃) and 1 part of silicone powder dispersing agent are poured into a mixer, treated for 5min at the rotating speed of 300r/min, and stirred and mixed uniformly.

(27) The mixture was placed into the feed opening of the main feed of the twin-screw extruder, and the materials were melt-mixed in the twin-screw extruder (extrusion temperature was 220 ℃, and main machine rotation speed was 450 rpm).

(28) And drawing the melt obtained by melt mixing at a constant moving speed through a shaping die, cooling through a water tank, air-drying and granulating to obtain the antistatic HIPS composite material with the particle diameter of 2-3 mm.

In a twin screw extruder, the screw combinations of conveying shear segments may be in the order 56/56, 96/96, 96/48, 72/72, 64/64, 45 °/5/56, 60 °/4/44 and 90 °/5/56; the screw combination sequence of the melt plasticizing stage may be K30/5/56, K45/4/56, K60/5/44, 44/44, K45/6/56, K60/5/44, 44/44, K60/4/56, K90/5/56, 44/44, K60/4/44, K60/5/56, K90/4/44 and 44/22L; the screw combination sequence of the mixing homogenization sections can be K60/5/56, K90/5/56, 72/72, C18, 44/44, K60/5/56, K90/5/56, K60/5/44L, 44/44, C18, 72/72, K60/5/56 and K90/5/56; the screw combination sequence of the vacuum exhaust section can be 44/44L, 72/72, 96/96 and 72/72; the screw combination sequence of the extrusion build-up sections may be 72/72, 56/56, 72/72 and 44/44.

Example 3

1. Preparation of modified carbon nano tube master batch:

(31) Pretreating glass beads: and (3) washing the glass beads with alkali, then washing with acid, and washing with water until the washing liquid is neutral, so that the surfaces of the glass beads have more hydroxyl groups.

(32) 3- (2, 3-epoxypropoxy) propyl trimethoxy silane (A-187) was weighed out and dissolved in water-ethanol (volume ratio 1:3) mixed solution (silane coupling agent mass concentration 3 wt%) and then acetic acid (CH) ₃ COOH) solution to adjust the pH of the solution to a range of 4-6. Adding the treated glass beads, stirring at 75 ℃ for reaction for 20-40min, filtering, washing and drying.

(33) Adding gamma-aminopropyl triethoxysilane (KH 550) (the mass concentration of the silane coupling agent is 3 wt%) into deionized water and ethanol (volume ratio is 1:3) as mixed solvents under stirring, adjusting the pH value to 5.0-6.0 by adopting hydrochloric acid (HCl), adding carbon nano tube powder, stirring and reacting at 60 ℃ for 9 hours, filtering, washing to neutrality, and drying at high temperature of 150 ℃ to obtain the carbon nano tube modified by the aminosilane coupling agent.

(34) And (3) mixing the substances obtained in the steps (32) and (33) into carbon nano tubes according to the mass ratio: glass beads=7:1 were reacted in an alkaline solution (temperature 40 ℃, PH 8-10, time 4 h) to obtain carbon nanotube-grafted glass bead composites.

(35) And uniformly mixing 32% of the carbon nanotube-connected glass microsphere compound with 65% of PVC resin and 3% of silicone powder dispersing agent, and performing melt extrusion granulation to obtain the modified carbon nanotube master batch.

2. Preparation of antistatic composite material:

taking the substrate resin as PE and the melting temperature as 110 ℃ as an example, the extrusion process can comprise the following steps:

(36) 85 parts of matrix resin PE, 25 parts of modified carbon nanotube master batch (the first resin is PVC resin with the melting temperature of 160 ℃) and 2 parts of silicone powder dispersing agent are poured into a mixer, treated for 7min at the rotating speed of 200r/min, and stirred and mixed uniformly.

(37) The mixture was placed into the feed opening of the main feed of the twin-screw extruder, and the materials were melt-mixed by the twin-screw extruder (extrusion temperature was 140 ℃, and main machine rotation speed was 480 rpm).

(38) And drawing the melt obtained by melt mixing at a constant moving speed through a shaping die, cooling through a water tank, air-drying and granulating to obtain the antistatic PE composite material with the particle diameter of 2-3 mm.

In a twin screw extruder, the screw combinations of conveying shear segments may be in the order 56/56, 96/96, 96/48, 72/72, 64/64, 45 °/5/56, 60 °/4/44 and 90 °/5/56; the screw combination sequence of the melt plasticizing stage may be K30/5/56, K45/4/56, K60/5/44, 44/44, K45/6/56, K60/5/44, 44/44, K60/4/56, K90/5/56, 44/44, K60/4/44, K60/5/56, K90/4/44 and 44/22L; the screw combination sequence of the mixing homogenization sections can be K60/5/56, K90/5/56, 72/72, C18, 44/44, K60/5/56, K90/5/56, K60/5/44L, 44/44, C18, 72/72, K60/5/56 and K90/5/56; the screw combination sequence of the vacuum exhaust section can be 44/44L, 72/72, 96/96 and 72/72; the screw combination sequence of the extrusion build-up sections may be 72/72, 56/56, 72/72 and 44/44.

Example 4

1. Preparation of modified carbon nano tube master batch:

(41) Pretreating glass beads: and (3) washing the glass beads with alkali, then washing with acid, and washing with water until the washing liquid is neutral, so that the surfaces of the glass beads have more hydroxyl groups.

(42) 3- (2, 3-epoxypropoxy) propyl trimethoxy silane (A-187) was weighed out and dissolved in water-ethanol (volume ratio 1:3) mixed solution (silane coupling agent mass concentration 4 wt%) and then acetic acid (CH) ₃ COOH) solution to adjust the pH of the solution to a range of 4-6. Adding the treated glass beads, stirring at 75 ℃ for reaction for 20-40min, filtering, washing and drying.

(43) Adding gamma-aminopropyl triethoxysilane (KH 550) (the mass concentration of the silane coupling agent is 3 wt%) into deionized water and ethanol (volume ratio is 1:3) as mixed solvents under stirring, adjusting the pH value to 5.0-6.0 by adopting hydrochloric acid (HCl), adding carbon nano tube powder, stirring and reacting at 60 ℃ for 9 hours, filtering, washing to neutrality, and drying at high temperature of 130 ℃ to obtain the carbon nano tube modified by the aminosilane coupling agent.

(44) And (3) mixing the substances obtained in the steps (42) and (43) into carbon nano tubes according to the mass ratio: glass beads=8:1 were reacted in an alkaline solution (temperature 40 ℃, PH 8-10, time 4 h) to obtain carbon nanotube-grafted glass bead composites.

(45) And uniformly mixing 25% of the carbon nanotube-connected glass microsphere compound with 71% of ABS resin and 4% of talcum powder dispersing agent, and performing melt extrusion granulation to obtain the modified carbon nanotube master batch.

2. Preparation of antistatic composite material:

taking the matrix resin as PP and the melting temperature as 150 ℃ as an example, the extrusion process can comprise the following steps:

(46) 100 parts of matrix resin PP, 35 parts of modified carbon nanotube master batch (the first resin is ABS resin with the melting temperature of 200 ℃) and 1 part of silicone powder dispersing agent are poured into a mixer, treated for 8min at the rotating speed of 280r/min, and stirred and mixed uniformly.

(47) The mixture was placed into the feed opening of the main feed of the twin-screw extruder, and the materials were melt-mixed by the twin-screw extruder (extrusion temperature was 180 ℃, and main machine rotation speed was 420 rpm).

(48) And drawing the melt obtained by melt mixing at a constant moving speed through a shaping die, cooling through a water tank, air-drying and granulating to obtain the antistatic PP composite material with the particle diameter of 2-3 mm.

In a twin screw extruder, the screw combinations of conveying shear segments may be in the order 56/56, 96/96, 96/48, 72/72, 64/64, 45 °/5/56, 60 °/4/44 and 90 °/5/56; the screw combination sequence of the melt plasticizing stage may be K30/5/56, K45/4/56, K60/5/44, 44/44, K45/6/56, K60/5/44, 44/44, K60/4/56, K90/5/56, 44/44, K60/4/44, K60/5/56, K90/4/44 and 44/22L; the screw combination sequence of the mixing homogenization sections can be K60/5/56, K90/5/56, 72/72, C18, 44/44, K60/5/56, K90/5/56, K60/5/44L, 44/44, C18, 72/72, K60/5/56 and K90/5/56; the screw combination sequence of the vacuum exhaust section can be 44/44L, 72/72, 96/96 and 72/72; the screw combination sequence of the extrusion build-up sections may be 72/72, 56/56, 72/72 and 44/44.

Example 5

1. Preparation of modified carbon nano tube master batch:

(51) Pretreating glass beads: and (3) washing the glass beads with alkali, then washing with acid, and washing with water until the washing liquid is neutral, so that the surfaces of the glass beads have more hydroxyl groups.

(52) 3- (2, 3-epoxypropoxy) propyl trimethoxy silane (A-187) was weighed out and dissolved in water-ethanol (volume ratio 1:3) mixed solution (silane coupling agent mass concentration 5 wt%) and then acetic acid (CH) ₃ COOH) solution to adjust the pH of the solution to a range of 4-6. Adding the treated glass beads, stirring at 85 ℃ for reaction for 20-40min, filtering, washing and drying.

(53) Adding gamma-aminopropyl triethoxysilane (KH 550) (the mass concentration of the silane coupling agent is 3 wt%) into deionized water and ethanol (volume ratio is 1:3) as mixed solvents under stirring, adjusting the pH value to 5.0-6.0 by adopting hydrochloric acid (HCl), adding carbon nano tube powder, stirring and reacting at 60 ℃ for 9 hours, filtering, washing to neutrality, and drying at high temperature of 150 ℃ to obtain the carbon nano tube modified by the aminosilane coupling agent.

(54) And (3) mixing the substances obtained in the steps (52) and (53) into carbon nano tubes according to the mass ratio: glass beads=9:1 were reacted in an alkaline solution (temperature 40 ℃, PH 8-10, time 4 h) to obtain a carbon nanotube-grafted glass bead composite.

(55) Uniformly mixing 28% of carbon nanotube-based glass microsphere compound with 67% of PET resin and 5% of talcum powder dispersing agent, and performing melt extrusion granulation to obtain modified carbon nanotube master batch.

2. Preparation of antistatic composite material:

taking the base resin as PA and the melting temperature as 210 ℃ as an example, the extrusion process can comprise the following steps:

(56) 89 parts of matrix resin PS, 33 parts of modified carbon nanotube master batch (the first resin is PET resin, the melting temperature is 260 ℃) and 1 part of silicone powder dispersing agent are poured into a mixer, are treated for 8min at the rotating speed of 200r/min, and are stirred and mixed uniformly.

(57) The mixture was placed into the feed opening of the main feed of the twin-screw extruder, and the materials were melt-mixed by the twin-screw extruder (extrusion temperature 240 ℃ C., main machine rotation speed 400 rpm).

(58) And drawing the melt obtained by melt mixing at a constant moving speed through a shaping die, cooling through a water tank, air-drying and granulating to obtain the antistatic PS composite material with the particle diameter of 2-3 mm.

In a twin screw extruder, the screw combinations of conveying shear segments may be in the order 56/56, 96/96, 96/48, 72/72, 64/64, 45 °/5/56, 60 °/4/44 and 90 °/5/56; the screw combination sequence of the melt plasticizing stage may be K30/5/56, K45/4/56, K60/5/44, 44/44, K45/6/56, K60/5/44, 44/44, K60/4/56, K90/5/56, 44/44, K60/4/44, K60/5/56, K90/4/44 and 44/22L; the screw combination sequence of the mixing homogenization sections can be K60/5/56, K90/5/56, 72/72, C18, 44/44, K60/5/56, K90/5/56, K60/5/44L, 44/44, C18, 72/72, K60/5/56 and K90/5/56; the screw combination sequence of the vacuum exhaust section can be 44/44L, 72/72, 96/96 and 72/72; the screw combination sequence of the extrusion build-up sections may be 72/72, 56/56, 72/72 and 44/44.

Antistatic composite material of comparative example and preparation method example thereof:

comparative example 1

Compared with example 2, the difference is in the preparation of modified carbon nanotube master batch:

in comparative example 1, 30% of commercially available carbon nanotubes, 69% of PBT resin and 1% of mica powder dispersant were uniformly mixed, and then melt-extruded and pelletized to obtain a modified carbon nanotube master batch.

Other preparation procedures are the same as in example 2, and are not repeated here.

Comparative example 2

Compared with example 2, the method is characterized in that carbon nanotubes are grafted on a layered silicate mineral to prepare modified carbon nanotube master batch, and the steps are as follows:

(61) Pretreatment of vermiculite: and (3) washing vermiculite with alkali, acid, and washing until the washing liquid is neutral, so that the surface of the vermiculite has more hydroxyl groups.

(62) 3- (2, 3-glycidoxy) propyl trimethoxy silane (A-187) with certain mass is weighed and dissolved in a mixed solution of water and ethanol (the volume ratio is 1:3) (the mass concentration of the silane coupling agent is 2wt percent), and then the pH value of the solution is regulated to be in the range of 4-6 by acetic acid solution. Adding treated vermiculite, stirring at 70 ℃ for reaction for 20-40min, filtering, washing and drying.

(63) Adding gamma-aminopropyl triethoxysilane (KH 550) (the mass concentration of the silane coupling agent is 3 wt%) into deionized water and ethanol (volume ratio is 1:3) as mixed solvents under stirring, adjusting the pH value to 5.0-6.0 with hydrochloric acid, adding carbon nanotube powder, stirring at 60 ℃ for reaction for 8h, filtering, washing to neutrality, and drying at high temperature of 140 ℃ to obtain the carbon nanotube modified by the aminosilane coupling agent.

(64) And (3) mixing the substances obtained in the steps (32) and (33) into carbon nano tubes according to the mass ratio: vermiculite=6:1 reacted in alkaline solution (temperature 40 ℃, PH 8-10, time 5 h) to obtain carbon nanotube-grafted vermiculite composite.

(65) Uniformly mixing 30% of the carbon nanotube-vermiculite composite with 69% of PBT resin and 1% of mica powder dispersing agent, and performing melt extrusion granulation to obtain modified carbon nanotube master batch.

Other preparation procedures are the same as in example 2, and are not repeated here.

Comparative example 3

The difference compared to example 2 is the different combination of screws in the twin screw extruder.

In a twin screw extruder, the screw combination order of the conveying shear segments may be 56/56, 96/96, 96/48, 72/72, 64/64, 96/96 and 72/72; the screw combination sequence of the melt plasticizing stage may be K30/5/56, K45/4/56, K60/5/44, 44/44, K30/5/56, K45/5/44, 44/44, K45/4/56, K60/5/56, 44/44, K45/4/44, K60/5/56, K90/4/44 and 44/22L; the screw combination sequence of the mixing homogenization sections can be K45 DEG/4/56, K60 DEG/5/56, 72/72, K45 DEG/5/56, K60 DEG/5/44L, 44/44, K45 DEG/5/56, K60 DEG/5/56 and K90 DEG/5/56; the screw combination sequence of the vacuum exhaust section can be 44/44L, 72/72, 96/96 and 72/72; the screw combination sequence of the extrusion build-up sections may be 72/72, 56/56, 72/72 and 44/44.

Other preparation procedures are the same as in example 2, and are not repeated here.

Comparative example 4

The difference compared to example 2 is the processing temperature, which is specifically as follows.

The extrusion temperature in comparative example 4 was 250℃and the host rotation speed was 450rpm.

Other preparation procedures are the same as in example 2, and are not repeated here.

Performance testing

The samples of the antistatic composite materials prepared in examples 1 to 5 and comparative examples 1 to 4 of the present application were molded into test bars according to standard sizes, and each sample was tested for tensile strength, flexural strength, impact strength, surface average resistivity, surface resistivity and surface flatness, respectively, and the test results are shown in table 1 below.

The tensile strength test method includes: the test conditions were 5Kg, 50 ℃/h, according to ISO (International Organization For Standardization ) 527:2010 (E) standard.

The method for testing the bending strength comprises the following steps: the test speed was 2mm/min according to ISO 178:2010 (E).

The method for testing the impact strength comprises the following steps: the test was carried out at 23℃with an impact energy of 4J according to ISO 179-1:2010 (E).

The method for testing the surface resistivity comprises the following steps: the DC comparison method is adopted for testing, and the test equipment and the measurement error accord with the specification of GB/T3048.5. The surface resistivity is measured by measuring the surface resistivity of 10 positions on the front and back surfaces of the test bar, and the surface average resistivity is the average value of 10 resistivity values.

TABLE 1

As can be seen from table 1, in example 1 of the present application, the mass concentration of the coupling agent, the ratio of the carbon nanotubes to the glass beads, the first resin type, the matrix resin type, the melting temperature, etc. are slightly different from example 2, so that the preparation of the modified carbon nanotube master batch in comparative examples 1 and 2 is different from example 1 compared with comparative examples 1 to 4, resulting in uneven dispersion of the carbon nanotube composite itself in the prepared modified carbon nanotube master batch, reduced dispersion uniformity during the formation of the antistatic composite, and further increased surface resistivity of the product, and significant formation of pocks due to agglomeration of carbon nanotubes. The screw combination in comparative example 3 is different from that in example 1, the shearing dispersion did not achieve the desired effect, resulting in significant carbon nanotube agglomeration. In comparative example 4, the processing temperature was higher than in example 1, the modified carbon nanotube master batch was completely melted, and the degree of freedom of the carbon nanotubes was increased, resulting in further agglomeration during the molding process.

Compared with comparative examples 1-4, the preparation of the modified carbon nanotube master batch in comparative examples 1 and 2 is different from that in example 2, so that the carbon nanotube compound in the prepared modified carbon nanotube master batch is unevenly dispersed, the dispersion uniformity in the forming process of the antistatic composite material is reduced, the surface resistivity of the product is further increased, and the carbon nanotube agglomeration obviously forms pocks. The screw combination in comparative example 3 is different from that in example 2, the shearing dispersion did not achieve the desired effect, resulting in significant carbon nanotube agglomeration. In comparative example 4, the processing temperature was higher than in example 2, the modified carbon nanotube master batch was completely melted, and the degree of freedom of the carbon nanotubes was increased, resulting in further agglomeration during the molding process.

In this application, in example 3, compared with example 2, only the mass concentration of the coupling agent, the ratio of the carbon nanotubes to the glass beads, the type of the first resin, the type of the matrix resin, the melting temperature, etc. are slightly different, so that in example 3, compared with comparative examples 1 to 4, the preparation of the modified carbon nanotube master batch in comparative examples 1 and 2 is different from example 3, resulting in uneven dispersion of the self carbon nanotube composite in the prepared modified carbon nanotube master batch, reduced dispersion uniformity in the forming process of the antistatic composite material, and further resulting in increased surface resistivity of the product, and obvious formation of pocks due to carbon nanotube aggregation. The screw combination in comparative example 3 is different from that in example 3, the shearing dispersion did not achieve the desired effect, resulting in significant carbon nanotube agglomeration. The processing temperature in comparative example 4 is higher than that in example 3, the modified carbon nanotube master batch is completely melted, and the degree of freedom of the carbon nanotubes is increased, which leads to further agglomeration during the molding process.

In this application, in example 4, compared with example 2, only the mass concentration of the coupling agent, the ratio of the carbon nanotubes to the glass beads, the type of the first resin, the type of the matrix resin, the melting temperature, etc. are slightly different, so that in example 4, compared with comparative examples 1 to 4, the preparation of the modified carbon nanotube master batch in comparative examples 1 and 2 is different from example 4, resulting in uneven dispersion of the self carbon nanotube composite in the prepared modified carbon nanotube master batch, reduced dispersion uniformity in the forming process of the antistatic composite material, and further resulting in increased surface resistivity of the product, and obvious formation of pocks due to carbon nanotube aggregation. The screw combination in comparative example 3 is different from that in example 4, the shearing dispersion did not achieve the desired effect, resulting in significant carbon nanotube agglomeration. The processing temperature in comparative example 4 is higher than that in example 4, the modified carbon nanotube master batch is completely melted, and the degree of freedom of the carbon nanotubes is increased, which leads to further agglomeration during the molding process.

In this application, in example 5, compared with example 2, only the mass concentration of the coupling agent, the ratio of the carbon nanotubes to the glass beads, the type of the first resin, the type of the matrix resin, the melting temperature, etc. are slightly different, so that in example 5, compared with comparative examples 1 to 4, the preparation of the modified carbon nanotube master batch in comparative examples 1 and 2 is different from example 5, resulting in uneven dispersion of the self carbon nanotube composite in the prepared modified carbon nanotube master batch, reduced dispersion uniformity in the forming process of the antistatic composite material, and further resulting in increased surface resistivity of the product, and obvious formation of pocks due to carbon nanotube aggregation. The screw combination in comparative example 3 is different from that in example 5, the shearing dispersion did not achieve the desired effect, resulting in significant carbon nanotube agglomeration. In comparative example 4, the processing temperature was higher than in example 5, the modified carbon nanotube master batch was completely melted, and the degree of freedom of the carbon nanotubes was increased, resulting in further agglomeration during the molding process.

Only matters related to the point of the invention will be described herein, and the rest may be obtained by referring to the related art, and will not be described in detail herein.

The foregoing examples represent only a few embodiments of the present application, which are described in more detail and are not thereby to be construed as limiting the scope of the present application. It should be noted that it would be apparent to those skilled in the art that various modifications and improvements could be made without departing from the spirit of the present application, which would be within the scope of the present application. Accordingly, the scope of protection of the present application is to be determined by the claims appended hereto.

Claims (10)

1. The antistatic composite material is characterized by comprising the following components in parts by weight:

80-100 parts of matrix resin;

1-5 parts of matrix dispersing agent;

20-40 parts of modified carbon nano tube master batch;

the modified carbon nano tube master batch comprises a first resin, a carbon nano tube grafted spherical particle compound and a first dispersing agent;

wherein the melting temperature of the first resin is 30-60 ℃ higher than the melting temperature of the matrix resin, and the melting processing temperature in the preparation process of the antistatic composite material is 10-20 ℃ lower than the melting temperature of the first resin.

2. The antistatic composite material according to claim 1, wherein the modified carbon nanotube master batch is prepared from the following raw materials in parts by weight:

50-80 parts of a first resin;

10-20 parts of carbon nano tubes;

5-20 parts of spherical particles;

1-5 parts of a first dispersing agent.

3. The antistatic composite material according to claim 2, wherein the surface of the spherical particles is grafted with epoxy groups, the surface of the carbon nanotubes is grafted with amino groups, and the epoxy groups and the amino groups undergo a bonding reaction so that the carbon nanotubes are grafted on the surface of the spherical particles.

4. An antistatic composite according to claim 3, wherein the spherical particles comprise spherical particles grafted with an epoxy siloxane coupling agent and the carbon nanotubes comprise carbon nanotubes grafted with an aminosiloxane coupling agent.

5. The antistatic composite according to claim 1 or 2, wherein the matrix resin comprises a thermoplastic resin comprising at least one of polyethylene, polypropylene, polystyrene, polycarbonate, polyamide, polyoxymethylene, polyphenylene oxide, ABS;

and/or the number of the groups of groups,

the first resin comprises at least one of polyvinyl chloride, polyethylene terephthalate, polycarbonate, polytetrafluoroethylene, polyether and aromatic heterocyclic polymer.

6. The antistatic composite material according to claim 1 or 2, wherein the diameter of the carbon nanotubes ranges from 1.0 to 6.0nm;

and/or the number of the groups of groups,

the length range of the carbon nano tube comprises 10-100 mu m;

and/or the number of the groups of groups,

the length-diameter ratio of the carbon nano tube ranges from 5000:1 to 120000:1;

and/or the number of the groups of groups,

the specific surface area of the carbon nano tube ranges from 800 m to 1200m ² /g；

And/or the number of the groups of groups,

raman spectrum I of the carbon nanotubes _D /I _G 0.3-0.7;

and/or the number of the groups of groups,

the powder resistivity range of the carbon nano tube comprises 0.1-5mΩ cm.

7. The preparation method of the antistatic composite material is characterized by comprising the following steps:

reacting the carbon nano tube with spherical particles in an alkaline solution to obtain a carbon nano tube grafted spherical particle compound;

Uniformly mixing the carbon nanotube grafted spherical particle compound, the first resin and the first dispersing agent, and then treating to obtain modified carbon nanotube master batch;

and uniformly mixing the modified carbon nanotube master batch with matrix resin and matrix dispersing agent, and then treating to obtain the antistatic composite material.

8. The method of preparing an antistatic composite material according to claim 7, wherein the reacting the carbon nanotubes with the spherical particles in an alkaline solution to obtain a carbon nanotube-grafted spherical particle composite comprises:

and (3) reacting the carbon nano tube grafted with the amino group with the glass bead grafted with the epoxy group in the alkaline solution to obtain the carbon nano tube grafted glass bead compound.

9. The method of preparing an antistatic composite material according to claim 7, wherein the uniformly mixing the carbon nanotube-grafted spherical particle composite with the first resin and the first dispersant and then treating the mixture to obtain a modified carbon nanotube master batch comprises:

uniformly mixing the carbon nanotube-grafted spherical particle compound, first resin and a first dispersing agent, and then carrying out melt extrusion granulation to obtain the modified carbon nanotube master batch; wherein, the melt extrusion granulation at least comprises a melt plasticizing section and a mixing homogenizing section.

10. The method for preparing an antistatic composite material according to claim 7, wherein the step of uniformly mixing the modified carbon nanotube master batch with a matrix resin and a matrix dispersant and then treating the mixture to obtain the antistatic composite material comprises the steps of:

uniformly mixing the modified carbon nanotube master batch with the matrix resin and the matrix dispersing agent, and then performing screw extrusion granulation; wherein, screw extrusion granulation adopts the screw combination as follows: the screw combination sequence of the conveying shearing section is 56/56, 96/96, 96/48, 72/72, 64/64, 45 DEG/5/56, 60 DEG/4/44, 90 DEG/5/56; the screw combination sequence of the melt plasticizing section is K30 degrees/5/56, K45 degrees/4/56, K60 degrees/5/44, 44/44, K45 degrees/6/56, K60 degrees/5/44, 44/44, K60 degrees/4/56, K90 degrees/5/56, 44/44, K60 degrees/4/44, K60 degrees/5/56, K90 degrees/4/44, 44/22L; the screw combination sequence of the mixing homogenization sections is K60 degrees/5/56, K90 degrees/5/56, 72/72, C18, 44/44, K60 degrees/5/56, K90 degrees/5/56, K60 degrees/5/44L, 44/44, C18, 72/72, K60 degrees/5/56, K90 degrees/5/56; the screw combination sequence of the vacuum exhaust section is 44/44L, 72/72, 96/96 and 72/72; the screw combination sequence of the extrusion build-up section is 72/72, 56/56, 72/72, 44/44.