Detailed Description
In order to describe the technical contents, the achieved objects and effects of the present invention in detail, the following description will be made with reference to the embodiments.
The most critical concept of the invention is as follows: and mixing titanium dioxide with high dielectric constant with the syndiotactic polystyrene resin to improve the overall dielectric constant of the prepared liquid crystal polymer material.
The invention discloses a liquid crystal polymer material for the field of 5G communication, which comprises the following raw materials in parts by weight: 30 to 80 parts of Syndiotactic Polystyrene (SPS), 20 to 60 parts of titanium dioxide, 1 to 5 parts of calcium stearate, 0.1 to 1 part of antioxidant and 0.1 to 30 parts of glass fiber.
Preferably, the feed comprises the following raw materials in parts by weight: 50 to 60 parts of Syndiotactic Polystyrene (SPS), 30 to 50 parts of titanium dioxide, 2 to 4 parts of calcium stearate, 0.3 to 0.8 part of antioxidant and 1 to 25 parts of glass fiber.
From the above description, the beneficial effects of the invention are as follows: the syndiotactic polystyrene is used as a parent material, titanium dioxide is added for modification, titanium dioxide is titanium oxide with higher dielectric constant, and the titanium dioxide with high dielectric constant is mixed with syndiotactic polystyrene resin to improve the overall dielectric constant of the prepared liquid crystal polymer material, so that the liquid crystal polymer material with low loss factor and high dielectric constant is obtained, and the application of the syndiotactic polystyrene compound in the field of high 5G communication is effectively improved. The glass fiber is a reinforcing material, and can improve the physical properties of the liquid crystal polymer material.
Further, the Syndiotactic Polystyrene (SPS) resin has a molecular weight of 30W to 50W and a polymerization degree of 3000 to 5000.
From the above description, it is apparent that syndiotactic polystyrene resin has a molecular weight of 30W to 50W, a degree of polymerization of 3000 to 5000, good flowability, and certain mechanical properties, and a certain processability and strength even after a high proportion of inorganic filler is added.
The other technical scheme of the invention is as follows: a preparation method of a liquid crystal polymer material for the field of 5G communication comprises the following steps:
s1: respectively drying syndiotactic polystyrene resin, titanium dioxide and glass fiber;
S2: dispersing the dried syndiotactic polystyrene resin, titanium dioxide, calcium stearate and an antioxidant to obtain a mixture;
S3: and (3) carrying out melt mixing on the mixture, adding glass fibers, extruding, bracing, cooling and granulating to obtain the liquid crystal polymer material.
From the above description, it is known that mixing titanium dioxide with a high dielectric constant with syndiotactic polystyrene resin increases the overall dielectric constant of the liquid crystal polymer material prepared.
The calcium stearate is used as a lubricant to increase the lubricity between the syndiotactic polystyrene resin and equipment during melt mixing and prevent the resin from adhering to the equipment and producing impurities by repeated heating and carbonization.
Further, the drying treatment time is 4-8 hours.
From the above description, the purpose of the drying treatment is to reduce the water content in the raw materials, avoid the void in the middle of the extruded pellets due to the evaporation of water vapor during the melt mixing process, and avoid the influence of water stains on the surface of the product after the modified liquid crystal polymer material is molded into the product by an injection molding machine; furthermore, the water content has an influence on the dielectric property of the material, and the larger the water content is, the worse the dielectric property is, and the dielectric property of the liquid crystal polymer material can be improved after the liquid crystal polymer material is dried.
Further, the time of the dispersion treatment is 2 to 10 minutes.
From the above description, the dispersion treatment time is short, and the uniformity of the mixture is poor; the dispersion time is long and the efficiency is reduced.
Further, in the step S3, a double-screw extruder is used for melt mixing and extrusion, and the temperature from a die head to a feeding port of the double-screw extruder is 280-300 ℃, 290-320 ℃, 280-290 ℃, 270-290 ℃ and 240-270 ℃ in sequence.
From the above description, it is understood that the twin-screw extruder sets temperature parameters according to Tg, tm and decomposition temperature of syndiotactic polystyrene, the temperature of 280-300 ℃ is die temperature, 290-320 ℃, 280-290 ℃, 270-290 ℃, 240-270 ℃ is the temperature of the screw 5/4/3/2/1 region of the twin-screw extruder in sequence, the higher of these temperatures can cause the SPS to be oxidized and decomposed in the screw, the mechanical properties can be reduced, the resin color can be yellowing, the lower of the temperature can cause the resin fluidity to be poor, the resin cannot be fully mixed with inorganic filler, and the processability is poor.
Further, the dispersion treatment of S2 is to premix the syndiotactic polystyrene resin and the titanium dioxide.
From the above description, it is known that the syndiotactic polystyrene and the titanium dioxide are usually premixed by a high mixer or a planetary mixer, and the premixed resin and titanium dioxide powder pass through a mixing zone and a plasticizing zone in the twin-screw extruder, and the syndiotactic polystyrene is in a molten state at the temperature due to the high enough screw temperature, and is subjected to secondary mixing under the action of the shearing force of the screw, so that the extruded titanium dioxide can be uniformly mixed in the syndiotactic polystyrene.
Example 1 of the present invention is:
a preparation method of a liquid crystal polymer material for the field of 5G communication comprises the following steps:
s1: drying 59g of syndiotactic polystyrene resin, 20g of titanium dioxide and 15g of glass fiber at 80 ℃ for 7 hours respectively;
S2: premixing the dried syndiotactic polystyrene resin and titanium dioxide for 10min at 480rpm, mixing with 5g of calcium stearate and 1g of antioxidant, and adding into a high-speed mixer for 8min dispersion treatment to obtain a mixture;
S3: and (3) putting the mixture into a double-screw extruder for melt mixing, adding glass fibers through a side material port of the double-screw extruder, extruding, bracing, cooling and granulating to obtain the liquid crystal polymer material.
The temperature of the twin-screw extruder from the die to the feed inlet was 290 ℃,300 ℃,310 ℃,285 ℃,280 ℃ and 260 ℃, respectively. The twin screw extruder was rotated at 150rpm, the feed frequency was 5Hz, and the side feed frequency was also 5Hz.
The Syndiotactic Polystyrene (SPS) resin has a molecular weight of 30W-50W and a polymerization degree of 3000-5000. The titanium dioxide is QTO-25M. The antioxidant is a basf antioxidant 1010 and a basf antioxidant 168 according to a ratio of 1:1, compounding powder.
Example 2 of the present invention is:
Example 2 differs from example 1 in that: 44g syndiotactic polystyrene resin and 35g titanium dioxide
Example 3 of the present invention is:
example 3 differs from example 1 in that: 34g syndiotactic polystyrene resin and 45g titanium dioxide
Example 4 of the present invention is:
a preparation method of a liquid crystal polymer material for the field of 5G communication comprises the following steps:
s1: drying 40g of syndiotactic polystyrene resin, 60g of titanium dioxide and 0.1g of glass fiber at 80 ℃ for 4 hours respectively;
S2: premixing the dried syndiotactic polystyrene resin and titanium dioxide for 10min at 480rpm, mixing with 1g of calcium stearate and 0.1g of antioxidant, and adding into a high-speed mixer for dispersing for 2min to obtain a mixture;
S3: and (3) putting the mixture into a double-screw extruder for melt mixing, adding glass fibers through a side material port of the double-screw extruder, extruding, bracing, cooling and granulating to obtain the liquid crystal polymer material.
The temperature of the twin-screw extruder from the die to the feed inlet was 280 ℃,290 ℃,290 ℃,280 ℃,270 ℃,240 ℃, respectively. The twin screw extruder was rotated at 150RPM, the feed frequency was 5Hz, and the side feed frequency was also 5Hz.
The Syndiotactic Polystyrene (SPS) resin has a molecular weight of 30W-50W and a polymerization degree of 3000-5000. The titanium dioxide is QTO-25M.
Example 5 of the present invention is:
a preparation method of a liquid crystal polymer material for the field of 5G communication comprises the following steps:
S1: drying 80g of syndiotactic polystyrene resin, 20g of titanium dioxide and 30g of glass fiber at 80 ℃ for 8 hours respectively;
S2: premixing the dried syndiotactic polystyrene resin and titanium dioxide for 10min at 480rpm, mixing with 4g of calcium stearate and 0.7g of antioxidant, and adding into a high-speed mixer for 10min dispersion treatment to obtain a mixture;
S3: and (3) putting the mixture into a double-screw extruder for melt mixing, adding glass fibers through a side material port of the double-screw extruder, extruding, bracing, cooling and granulating to obtain the liquid crystal polymer material.
The temperature of the twin-screw extruder from the die to the feed inlet was 300 ℃,320 ℃,320 ℃,290 ℃,290 ℃,270 ℃, respectively. The twin screw extruder was rotated at 150RPM, the feed frequency was 5Hz, and the side feed frequency was also 5Hz.
The Syndiotactic Polystyrene (SPS) resin has a molecular weight of 30W-50W and a polymerization degree of 3000-5000. The titanium dioxide is QTO-25M.
Comparative example 1 of the present invention is:
comparative example 1 differs from example 1 in that: the syndiotactic polystyrene resin was 100g, and no titanium dioxide, calcium stearate antioxidant and glass fiber were added.
Comparative example 2 of the present invention is:
Comparative example 2 differs from example 1 in that: the syndiotactic polystyrene resin was 64g, the glass fiber was 30g, and no titanium dioxide was added.
The liquid crystal polymer materials prepared in examples 1 to 3 and comparative examples 1 to 2 were tested for flexural strength, tensile strength, dielectric constant and loss factor, and the test results are shown in table 1.
TABLE 1
As is clear from Table 1, the dielectric constant of the liquid crystal polymer material can be increased by adding titanium dioxide, the dielectric loss factor can be reduced by adding syndiotactic polystyrene, and the flexural strength and tensile strength can be improved by adding glass fiber.
In summary, the liquid crystal polymer material for the 5G communication field provided by the invention takes syndiotactic polystyrene as a matrix material, titanium dioxide is added for modification, titanium dioxide is titanium oxide with higher dielectric constant, and the overall dielectric constant of the prepared liquid crystal polymer material is improved by mixing titanium dioxide with high dielectric constant with the syndiotactic polystyrene resin, so that the liquid crystal polymer material with low loss factor and high dielectric constant is obtained, and the application of the syndiotactic polystyrene compound in the high 5G communication field is effectively improved.
The foregoing is merely exemplary embodiments of the present invention and are not intended to limit the scope of the present invention, and all equivalent modifications made by the present invention or direct or indirect application in the relevant art are intended to be included in the scope of the present invention.