CN116970287A - Modified LCP material and preparation method and application thereof - Google Patents

Abstract

The invention discloses a modified LCP material and its preparation method and application, and belongs to the technical field of polymer material modification. The modified LCP material provided by the invention includes the following preparation raw materials: chain extender and LCP resin; the chain extender is selected from epoxy chain extenders, and the epoxy chain extender contains two or more Alicyclic epoxy group. The present invention uses a specific chain extender to modify the LCP resin, which increases the viscosity of the LCP material even without the need for a compatibilizer. At the same time, it solves the problem of poor compatibility and poor dispersion between the chain extender and the matrix resin. To solve the problem of uniformity, the modified LCP material has better film-forming properties.

Description

A modified LCP material and its preparation method and application

Technical field

The invention belongs to the technical field of polymer material modification, and in particular relates to a modified LCP material and its preparation method and application.

Background technique

Liquid crystal polymer (LCP) has the characteristics of high temperature resistance, high mechanical strength, good chemical stability, low thermal expansion coefficient, low water absorption, low dielectric constant and low dielectric loss. It is widely used in electronic appliances, communications, aerospace and other fields. Broad application prospects. At present, the processing characteristics of domestic film-grade LCP resin are not comparable to those of film-grade LCP resins from Japan Polycarbonate and the United States Celanese. At the same time, due to the material characteristics of the LCP body, it has low viscosity and good fluidity in the molten state, resulting in its melt strength. Low, the film bubble is prone to instability during the blow molding process, and due to the orientation characteristics of the LCP molecular chain, it requires specific equipment for processing.

As far as polymer material modification technology is concerned, it can be divided into chemical modification and physical blending modification according to whether there are new and old chemical bonds formed and broken. Common chemical modifications include graft modification and block modification. Physical modification There are two types of properties: filling and enhanced modification. At present, LCP modification technology is more focused on LCP enhanced modification. For example, white graphene can be used to enhance the mechanical properties and thermal conductivity of LCP, glass fiber woven cloth filling modification can be used to improve the wear resistance of LCP, and LCP blown film can be improved. The best performance is to use polyphenylene ether (PPE) and maleic anhydride-grafted polyphenylene ether (PPE-g-MAH) to graft-modify LCP, but there are still problems of poor compatibility and uneven dispersion.

Even under the action of the compatibilizer PPE-g-MAH, PPE still has poor compatibility with the matrix resin LCP. The modified sample can clearly distinguish the two substances macroscopically; at the same time, due to poor compatibility and poor dispersion, Uniform, resulting in poor film-forming properties of the modified LCP. During the film blowing process, the film bubble is very prone to holes, making it impossible to continuously blow the film.

Therefore, there is a need for a method that can increase the viscosity of LCP while also solving the problems of poor compatibility and uneven dispersion of chain extenders, compatibilizers and matrix resin LCP, thereby achieving continuous film formation of modified LCP.

Contents of the invention

In order to overcome the problems existing in the above-mentioned prior art, one of the purposes of the present invention is to provide a modified LCP material. The LCP resin is modified by a specific chain extender. The modified LCP material obtained has a higher viscosity and Good compatibility and good film-forming properties.

The second object of the present invention is to provide an equipment for preparing the above modified LCP material.

The third object of the present invention is to provide a method for preparing the above-mentioned modified LCP material.

The fourth object of the present invention is to provide an application of the above-mentioned modified LCP material in the fields of electronic appliances, communications or aerospace.

In order to achieve the above objects, the technical solutions adopted by the present invention are:

The first aspect of the present invention provides a modified LCP material, including the following preparation raw materials: chain extender, LCP resin; the chain extender is selected from epoxy chain extender, and the epoxy chain extender contains Two or more alicyclic epoxy groups.

Preferably, the mass percentage of the chain extender in the raw material for preparing the modified LCP material is 0.1-2%; more preferably, it is 0.2-1.5%; even more preferably, it is 0.3-1%.

Preferably, among the chain extenders, the epoxy chain extender is selected from ADR chain extenders; further preferably, the ADR chain extenders include ADR-4468, ADR-4368CS, ADR-4370, ADR-4385, At least one of ADR-4380 or ADR-4300; further preferably, the ADR chain extender includes at least one of ADR-4468, ADR-4368CS or ADR-4370.

In some embodiments of the invention, the ADR chain extender is selected from ADR-4468.

Since ADR-4468 chain extender has 9 alicyclic epoxy groups, it is easier to react with the hydroxyl or carboxyl groups of the main chain of the LCP molecule to form branch chains, thus solving the problem of poor compatibility between LCP resin and chain extender. , which is beneficial to the viscosity-increasing modification of LCP resin.

Preferably, in the chain extender, the acid anhydride compound is selected from dianhydride compounds; further preferably, it is selected from pyromellitic dianhydride.

Preferably, in the chain extender, the isocyanate is selected from diisocyanate; more preferably, it is selected from toluene diisocyanate.

Liquid crystal polymers are polymers that can exist in a liquid crystal phase under certain conditions. They have the characteristics of both polymers and liquid crystal materials. According to the formation conditions of liquid crystals, they can be divided into thermotropic liquid crystal polymers (TLCP) and solvent-based polymers. Liquid crystalline polymer (LLCP).

Preferably, the LCP resin of the present invention is selected from thermotropic liquid crystal polymer (TLCP); further preferably, the LCP resin is selected from at least one of A950 and R8000; further preferably, the LCP resin is selected from Polyplastics A950 , CelanesA950, TiconaA950 or Blonde R8000 at least one.

Preferably, the melt index of the modified LCP material at 285°C and 1.2kg is 0.1-1g/10min; further preferably, it is 0.2-0.8g/10min.

Preferably, the viscosity of the modified LCP material is 10 ⁵ to 10 ⁹ mPa·s at 25°C and a frequency of 0.01 to 100/second; further preferably, it is 2×10 ⁵ to 8×10 ⁸ mPa·s.

The second aspect of the present invention provides an equipment for preparing the modified LCP material according to the first aspect of the present invention. The equipment includes a screw extrusion device, the screw extrusion device includes an engaging block, and the The meshing block is obtained by crisscrossing 4 or more strip-shaped meshing pieces. The angle between each two adjacent meshing pieces is 30 to 60°.

Preferably, the screw extrusion device includes a twin-screw extruder or a single-screw extruder; more preferably, it is a twin-screw extruder.

Preferably, the engaging block includes 4 to 10 strip-shaped engaging pieces; more preferably, 4 to 6 pieces.

Preferably, the angle between two adjacent meshing pieces is 30-60°; further preferably, it is 40-50°.

Preferably, the screw extrusion device includes 8 to 12 meshing blocks; more preferably, 8 to 10 meshing blocks.

Preferably, a threaded conveying element is connected between the engaging blocks; further preferably, a threaded conveying element is connected between every two adjacent engaging blocks.

In some specific embodiments of the present invention, the meshing block is obtained by cross-stacking five strip-shaped meshing pieces. The angle between two adjacent meshing pieces is 45°. The screw has a total of 9 meshing blocks, and each two meshing pieces A threaded conveying element is connected between the blocks. When this specific implementation is adopted, the material flow will be divided into two material flows each time it passes through an meshing piece. The screw will fully mix the material flow while rotating. The material flow passes through 9 meshing blocks and a total of 45 meshing pieces. , was divided into 2 ⁴⁵ material streams, and after multiple division and mixing, a good dispersion and mixing effect was achieved. In addition, in order to prevent gel agglomeration caused by excessive residence time of the material flow, threaded conveying elements are embedded between the meshing blocks to ensure sufficient reaction time between the chain extender and the LCP resin, and at the same time, the molten material flow is transported forward.

The third aspect of the present invention provides a method for preparing the modified LCP material according to the first aspect of the present invention, which includes the following steps: mixing the LCP resin and the chain extender and then performing extrusion granulation.

Preferably, in the preparation method, the mixing temperature for mixing the LCP resin and the chain extender is 40 to 120°C; more preferably, it is 50 to 110°C.

Preferably, in the preparation method, the mixing time for mixing the LCP resin and the chain extender is 3 to 40 minutes; further preferably, it is 5 to 30 minutes.

Preferably, in the preparation method, extrusion granulation is performed in a screw extruder; further preferably, a twin-screw extruder is used.

Preferably, the screw diameter of the screw extruder is 30 to 40 mm.

Preferably, the screw length-to-diameter ratio of the screw extruder is 40-50.

Preferably, in the preparation method, extrusion granulation includes the following steps: plasticizing mixing, extrusion drawing and cooling granulation.

Preferably, during the plasticizing mixing, the temperatures in each zone of the screw extruder are 210-230°C, 225-245°C, 230-250°C, 250-270°C, 255-275°C, 260-280°C, 260°C, respectively. ~280℃, 260~280℃, 270~290℃, 275~295℃.

Preferably, during the plasticizing mixing, the temperature of the screw extruder die is 275-295°C.

Preferably, in the plasticizing mixing, the screw speed of the screw extruder is 130 to 140 r/min.

Preferably, in the plasticizing mixing, the feeding speed is 4 to 10 r/min.

Preferably, in the preparation method, the LCP resin and the chain extender are mixed and then extruded and granulated twice.

Performing two extrusion granulations can make the LCP resin and chain extender more fully mixed, the viscosity-increasing modification effect will be better, and the film-forming performance of the modified LCP material will be better.

Preferably, in the preparation method, extrusion granulation is performed in the equipment described in the second aspect of the present invention.

The fourth aspect of the present invention provides an application of the modified LCP material described in the first aspect of the present invention in the fields of electronic appliances, communications or aerospace.

Preferably, the communication field is the field of 5G communication; further preferably, the 5G communication field is the field of antenna film materials for 5G communication.

The beneficial effects of the present invention are: the present invention uses a specific chain extender to modify the LCP resin. Even if a compatibilizer is not needed, the viscosity of the LCP material is still improved. At the same time, the problem between the chain extender and the matrix is solved. Due to the problems of poor resin compatibility and uneven dispersion, the modified LCP material has better film-forming properties.

Specifically, compared with the prior art, the present invention has the following advantages:

1. Among the chain extenders used in the present invention, the epoxy chain extender contains two or more alicyclic epoxy groups, so it is more likely to react with the hydroxyl or carboxyl groups in the main chain of the LCP molecule to form branches. chain, thereby solving the compatibility problem. While increasing the viscosity of the LCP material, it also solves the problem of poor compatibility and uneven dispersion between the chain extender and the matrix resin.

2. The equipment provided by the present invention adopts a meshing block of a specific composition. The meshing block is combined with a threaded conveying element and has the characteristics of low shear and strong mixing, which can improve the dispersion and mixing effect of the chain extender and the resin matrix. At the same time, it prevents the material from If the flow residence time is too long, the gel will agglomerate. A conveying element is embedded between the meshing block components to ensure sufficient reaction time between the chain extender and LCP, and at the same time, the molten material flow is transported forward.

3. The modified LCP material obtained by the present invention has high viscosity, good compatibility between raw materials, good film-forming performance, and is widely used in the fields of electronic appliances, communications, and aerospace.

Description of the drawings

Figure 1 is a schematic diagram of the screw structure of the screw extruder in the embodiment.

Figure 2 is a schematic diagram of the meshing block of the screw extruder in the embodiment.

Figure 3 is a schematic diagram of the screw conveying element of the screw extruder in the embodiment.

Figure 4 is a graph showing changes in viscosity of LCP materials in Example 1, Comparative Example 1 and Comparative Example 2.

Figure 5 is a physical diagram of the LCP material of Example 1 when the film blowing experiment was carried out.

Figure 6 is a physical picture of the LCP material of Example 2 when it was subjected to a film blowing experiment.

Figure 7 is the actual picture 1 of the LCP material of Comparative Example 2 when the film blowing experiment was carried out.

Figure 8 is an actual picture 2 of the LCP material of Comparative Example 2 when the film blowing experiment was carried out.

Detailed ways

The content of the present invention will be further described in detail below through specific examples. It should also be understood that the following examples are only used to further illustrate the present invention and cannot be understood as limiting the scope of the present invention. Some non-essential improvements and adjustments made by those skilled in the art based on the principles explained in the present invention all belong to the present invention. scope of protection. The specific process parameters in the following examples are only an example of the appropriate range, that is, those skilled in the art can make selections within the appropriate range through the description herein, and are not limited to the specific data of the examples below. Unless otherwise specified, the raw materials, reagents or devices used in the following examples and comparative examples can be obtained from conventional commercial sources, or can be obtained by existing known methods.

In some embodiments of the present invention, the engaging blocks and conveying elements are commercially available products, and the combination form is self-assembly; the manufacturer is Nanjing Ruixin, and the model is 45°/5/16.

In some embodiments of the present invention, the preparation method of modified LCP includes the following steps: a) raw material compounding; b) plasticizing and mixing; c) extruding strands; d) cooling and pelletizing.

Specific steps are as follows:

Step a) Compound the raw materials. Calculate in parts by weight, weigh 0.05-1 part of the chain extender and 99-99.95 parts of the LCP resin. The specific chain extender used is selected from ADR-4468; the LCP resin is selected from PolyplasticsA950 or CelanesA950LCP particles; Place chain extender ADR4468 and LCP resin particles in a high-speed mixer, disperse and mix at 50-110°C for 5-30 minutes to obtain a mixed material;

Step b) Plasticizing and mixing, place the mixed material prepared in the above steps into the hopper of a twin-screw extruder with a screw diameter of 35mm and a screw length-to-diameter ratio of 44. The temperature of each zone of the extruder and the die temperature are set to 220°C respectively. ℃, 235℃, 240℃, 260℃, 265℃, 270℃, 270℃, 270℃, 280℃, 285℃, 285℃, the feeding speed is 6r/min, the screw speed is 135r/min, mix the materials Carry out plasticizing and mixing to obtain a molten material in which the chain extender is evenly dispersed. The screw combination uses two threaded elements: conveying element and meshing block, which have the characteristics of low shear and strong mixing. In order to improve the dispersion and mixing effect of the chain extender and the resin matrix, 9 meshing block components are used in the screw combination (as shown in the figure) As shown in 1, 4, 2, and 3 meshing block components are used in areas ①②③ respectively, a is the meshing block, and b is the threaded conveying element). As shown in Figure 2, each meshing block consists of 5 meshing pieces in staggered angles. 45° composition. When the material flow passes through an meshing piece, it is divided into two flows. The screw fully mixes the material flow while rotating. After the material flow passes through 9 meshing blocks and a total of 45 meshing pieces, it is divided into ²⁴⁵ streams of material were produced, and after multiple splitting and mixing, a good dispersion and mixing effect was achieved. At the same time, in order to prevent gel agglomeration caused by the material staying for too long, threaded conveying elements are embedded between the meshing block components (as shown in Figure 3) to ensure sufficient reaction time between the chain extender and LCP, and at the same time, the molten material moves forward delivery;

Step c) Extruding the strip, the molten material is extruded outward through the cylindrical hole on the die under the extrusion force of the extruder, and at the same time, under the action of traction force, a continuous cylindrical strip is formed;

Step d) Cooling and granulating, the cylindrical strips are passed through a cooling water tank. After the cylindrical strips are cooled to an appropriate temperature, they enter the granulator for granulation to obtain modified LCP particles 1, which is the modified LCP material.

In other embodiments of the present invention, the preparation method of modified LCP includes the following steps: a) raw material compounding; b) plasticizing and mixing; c) extrusion and drawing; d) cooling and pelletizing; e) secondary extrusion Out of granulation.

Specific steps are as follows:

The specific steps of steps a) to d) are the same as those in the previous embodiment;

Step e) Secondary extrusion granulation. Repeat steps b), step c) and step d) on the modified LCP particles 1 to obtain modified LCP particles 2, which is the modified LCP material.

In some embodiments of the present invention, LCP is commercially available A950, specifically Polyplastics A950, Celanes A950, and Ticona A950. Commercially available A950 does not have a chain extender added, and its melting index is 1.9g/10min (285°C, 1.2kg) , the viscosity range is 1×10 ⁵ ~ 7×10 ⁸ mPa·s (0.01Hz-100Hz).

In some embodiments of the present invention, the use of specific screw combinations can improve the dispersion effect of the chain extender in the LCP matrix. The modified LCP material prepared by ordinary twin-screws has a weaker dispersion effect than the specific screw combination described in the embodiment of the present invention, resulting in poor dispersion of the chain extender in the LCP resin, and is prone to gel-like phenomena, resulting in modified LCP During the film blowing process, holes appeared intermittently and film formation could not be continued.

In some embodiments of the present invention, the addition of chain extender affects the melt index and viscosity of LCP. ADR-4468 chain extender can increase the viscosity of LCP resin and reduce the melt index of LCP resin, while TDE-85 can decrease the melt index of LCP resin. The viscosity of LCP resin and the melt index of LCP resin are improved. Therefore, the embodiments of the present invention use an epoxy chain extender containing two or more alicyclic epoxy groups, which can increase the viscosity of the LCP resin, reduce the melt index of the LCP resin, and obtain an improved film with good film-forming properties. Sexy LCP materials.

Example 1

This example provides a method for preparing modified LCP materials, which specifically includes the following steps:

Calculated in parts by weight, mix 0.7 parts of chain extender ADR-4468 and 99.3 parts of A950LCP in a high-speed mixer. Mix for 5-30 minutes at 50-110°C and then pour out the mixed material. At the same time, place the mixed material on a low temperature. The temperature of each zone of the extruder and the die head temperature in the hopper of the twin-screw extruder with strong shear dispersion screw combination are set to 220°C, 235°C, 240°C, 260°C, 265°C, 270°C, 270°C, 270°C respectively. ℃, 280 ℃, 285 ℃, 285 ℃, the feeding speed is 6r/min, the screw speed is 135r/min, the mixed material is melted, plasticized and granulated to obtain modified LCP granules 1, and then the modified LCP 1 is placed on the double In the hopper of the screw extruder, extrusion granulation is performed again with the same process parameters to obtain modified LCP particles 2, which is the modified LCP material.

Example 2

This example provides a method for preparing modified LCP materials, which specifically includes the following steps:

Calculated in parts by weight, mix 0.5 parts of chain extender ADR-4468 and 99.5 parts of A950LCP in a high-speed mixer. Mix at 50-110°C for 5-30 minutes and then pour out the mixed material. At the same time, place the mixed material in a low temperature The temperature of each zone of the extruder and the die head temperature in the hopper of the twin-screw extruder with strong shear dispersion screw combination are set to 220°C, 235°C, 240°C, 260°C, 265°C, 280°C, 280°C, 280°C respectively. ℃, 285℃, 285℃, 285℃, the feeding speed is 6r/min, the screw speed is 135r/min, the mixed material is melted, plasticized and granulated to obtain modified LCP particles 1, which is the modified LCP material.

Comparative example 1

This example provides a method for preparing LCP materials, which specifically includes the following steps:

Place the pure A950LCP particles in the hopper of a twin-screw extruder with low shear and strong dispersion screw combination. The temperature of each zone of the extruder and the die temperature are set to 220°C, 235°C, 240°C, 260°C, and 265°C respectively. ℃, 270℃, 270℃, 270℃, 280℃, 285℃, 285℃, the feeding speed is 6r/min, the screw speed is 135r/min, the pure material A950LCP is melted, plasticized and granulated to obtain the LCP Material.

Comparative example 2

This example provides a method for preparing modified LCP materials, which specifically includes the following steps:

Calculated in parts by weight, place 0.7 parts of chain extender TDE-85 (4,5-epoxyhexane-1,2-dicarboxylic acid diglycidyl ester) and 99.3 parts of A950LCP in a high-speed mixer at 50-110°C Under the conditions, pour out the mixed material after mixing for 5-30 minutes. At the same time, place the mixed material in the hopper of a twin-screw extruder with low shear and strong dispersion screw combination. The temperature of each zone of the extruder and the die temperature are set to 220 respectively. ℃, 235℃, 240℃, 260℃, 265℃, 270℃, 270℃, 270℃, 280℃, 285℃, 285℃, the feeding speed is 6r/min, the screw speed is 135r/min, mix the materials Melt, plasticize and granulate to obtain the modified LCP material.

Performance Testing

1) Record the current of the extruder during the granulation process. The extruder current can reflect the energy consumption of the material during the plasticization process of the twin-screw extruder, and indirectly reflects the increase in the viscosity of the modified material. Under the same process parameters (barrel temperature, screw speed, feeding speed are the same), due to the introduction of chain extender to block or graft the LCP molecular chain and increase its molecular chain, the melt plasticization process requires more Only a certain amount of energy consumption can make the molecular chains unwind and flow. That is, the greater the extruder current, the greater the viscosity of the material.

2) Test the melt index of the material at 285℃ and 1.2kg.

3) Use a rotational rheometer to measure the viscosity change of the material at 285°C.

4) Conduct a blown film experiment to test the film-forming performance of the material.

The results are recorded in Table 1.

Table 1 Material performance test results

Note: “0” represents the viscosity change baseline, “+” represents an increase in viscosity, and “-” represents a decrease in viscosity.

Comparative Example 1 did not add a chain extender for modification and was pure LCP resin. Comparative Example 1 was used as a reference group for viscosity changes. The viscosity change diagram of the LCP material of Example 1, Comparative Example 1 and Comparative Example 2 is shown in Figure 4. The viscosity of the modified LCP material of Example 1 is 2×10 ⁵ at 25°C and a frequency of 0.01 to 100/second. ^The viscosity of the modified LCP material of Comparative Example 2 is in the range of 7×10 ⁴ to 1.2×10 ⁸ mPa·s at 25°C and a frequency of 0.01 to 100/s. , at the same frequency, the viscosity of Comparative Example 2 is smaller. It can be seen that using the ADR chain extender in Example 1 can increase the viscosity of the LCP material, while using the TDE chain extender which also contains an epoxy group, since it has only one alicyclic epoxy group, the modification of the LCP material is The effect is poor and cannot increase the viscosity of LCP materials.

Figure 5 is a physical picture of the LCP material of Example 1 when the film blowing experiment is carried out. Figure 6 is a physical picture of the LCP material of Example 2 when the film blowing experiment is carried out. Figures 7 and 8 show the LCP material of Comparative Example 2 when the film blowing experiment is carried out. Physical Figure 1 and Actual Figure 2 during the membrane experiment show that during the film blowing process, the surface of the LCP membrane of Example 1 is smooth and has no holes. The modified LCP of Example 1 has better film-forming performance; implementation The surface of the LCP membrane of Example 2 has holes, but the degree of holes is small. The modified LCP of Example 1 has certain film-forming properties; the LCP membrane of Comparative Example 2 has larger holes, and the LCP membrane of Comparative Example 2 has larger holes. The modified LCP material has poor film-forming properties.

From the comparison between Figure 5 and Figures 7 and 8, it can be seen that there are no holes on the surface of the LCP film of Example 1 in Figure 5, the cylindrical film bubble is stably inflated and has a straight shape; while the LCP of Comparative Example 2 in Figures 7 and 8 There were holes on the surface of the membrane, and the cylindrical membrane bubble was extremely unstable when inflated, and its shape also swayed.

Although holes appear on the surface of the LCP film of Example 2 in Figure 6, the degree of holes is small and does not affect the film-forming performance of the material. The cylindrical film bubble is more stable in inflation and has a straighter shape.

In the embodiment of the present invention, when the modified LCP material that has been granulated only once is subjected to a blown film experiment, holes will appear intermittently, mainly due to the gel phenomenon caused by the uneven dispersion of the chain extender in the LCP matrix. Under the same process conditions in the film blowing process, there is infusible matter where there is gel, causing the film bubble to leak.

It can be seen that the present invention uses a specific chain extender to modify the LCP resin. Even if a compatibilizer is not needed, the viscosity of the LCP material is still increased. At the same time, the problem of poor compatibility between the chain extender and the matrix resin is solved. The problem of uneven dispersion, the film-forming performance of the modified LCP material is better; combined with the screw extruder with a specific structure of the meshing block and the threaded conveying element of the present invention, the obtained LCP material is fully mixed, which is beneficial to improving the material's degree of dispersion.

The embodiment of the present invention uses a specific chain extender, combined with a specific screw combination and extrusion granulation process, to improve the viscosity of LCP and solve the problem of chain extender and matrix even without using a compatibilizer. Solve the problems of poor resin compatibility and uneven dispersion to achieve continuous film formation of modified LCP materials. The modified LCP material obtained by the present invention has higher viscosity, good compatibility between raw materials, better film-forming performance, and is widely used in the fields of electronic appliances, communications, and aerospace.

Claims (10)

1. The modified LCP material is characterized by comprising the following preparation raw materials: chain extenders, LCP resins; the chain extender is selected from epoxy chain extenders, and the epoxy chain extender contains two or more alicyclic epoxy groups.

2. A modified LCP material according to claim 2, wherein the chain extender is present in the preparation material in an amount of 0.1 to 2% by mass.

3. A modified LCP material according to claim 1, wherein the epoxy-based chain extender is selected from ADR chain extenders.

4. A modified LCP material according to claim 1, wherein the LCP resin is selected from thermotropic liquid crystalline polymers.

5. An apparatus for preparing a modified LCP material as claimed in any one of claims 1 to 4, wherein the apparatus comprises a screw extrusion device comprising an engagement block formed by the cross lamination of 4 or more strip-shaped engagement pieces, each adjacent two engagement pieces having an included angle of 30 to 60 °.

6. The apparatus of claim 5, wherein the apparatus comprises 8-12 engagement blocks.

7. The apparatus of claim 5, wherein threaded conveying elements are connected between the engagement blocks.

8. A method of preparing a modified LCP material as claimed in any one of claims 1 to 4, comprising the steps of: the LCP resin and the chain extender are mixed and then extruded and granulated.

9. The method of claim 8, wherein the extrusion granulation is performed in the apparatus of any one of claims 5 to 7.

10. Use of a modified LCP material according to any one of claims 1 to 4 in the fields of electronics, communications or aerospace.