High-thermal-conductivity high-temperature-resistant heat-shrinkable material and preparation method thereof

Abstract

The invention provides a high-thermal-conductivity high-temperature-resistant heat-shrinkable material and a preparation method thereof. The high-thermal-conductivity high-temperature-resistant heat-shrinkable material comprises the following raw materials in parts by weight: 78-94 parts of modified polyaryletherketone; 5-20 parts of modified boron nitride; 0.5-1 part of a lubricant; 0.5 to 1 part of an antioxidant; according to the invention, firstly, through copolymerization modification and regulation of an aggregation state structure, the thermal shrinkage performance of polyaryletherketone is improved, so that the polyaryletherketone still keeps excellent thermal shrinkage performance at 200-350 DEG C, and meanwhile, the polyaryletherketone has excellent comprehensive properties such as corrosion resistance, radiation resistance and friction resistance; in addition, the surface of the heat-conducting nano ceramic is subjected to plasma treatment, so that the dispersity of the heat-conducting nano ceramic in a polyaryletherketone matrix can be improved, a heat-conducting passage is formed in the polyaryletherketone matrix more quickly, and the heat conductivity of the polyaryletherketone is remarkably improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of heat shrinkable materials, and particularly relates to a highly heat-conductive and high-temperature-resistant heat shrinkable material, a preparation method thereof, and uses thereof. Background Art

[0002] Heat shrinkable polymer materials refer to polymer materials that shrink in volume when heated. The memory property of heat shrinkable polymer materials can be used to produce heat shrinkable pipes, films, and profiles. The main feature is that they heat shrink and wrap around the outer surface of an object, and can perform functions such as insulation, moisture-proof, sealing, protection, and connection. With these special and excellent functions, heat shrinkable materials are widely used in fields such as insulation and heat protection of electronic components, communication, insulation protection of power cables, chemical industry, and sealing and anti-corrosion of petroleum pipelines.

[0003] Traditional heat shrinkable polymer materials, such as polyvinyl chloride, polyethylene, polypropylene, and polyester, have a low use temperature. Usually, the shrinkage effect starts to deteriorate when the temperature exceeds 150 °C. These polymer materials are flammable and have poor anti-aging and friction resistance properties, and cannot meet the increasingly demanding use environment. On the other hand, traditional heat shrinkable polymer materials achieve the purpose of heat shrinkage through chemical or irradiation cross-linking means, which results in these materials being unable to be recycled repeatedly and not meeting the increasingly stringent environmental protection requirements. And their thermal conductivity is generally low, and heat is easily accumulated during use, causing the material to fail quickly.

[0004] Polyaryletherketone (PAEK) is a semi-crystalline special engineering plastic. Its main structure is an all-aromatic polymer containing only benzene rings, carbonyl groups, and ether bonds. It also has excellent mechanical properties, insulation properties, corrosion resistance, weather resistance, flame retardancy, dimensional stability, etc. advantages. Therefore, since its engineering application, it has become the preferred material for replacing steel with plastic and is widely used in high-precision and advanced technology fields such as national defense and military industry, aerospace, and deep earth and deep sea exploration. However, its heat shrinkage performance is poor, and the heat shrinkage rate is only 24.7%, and at the same time, its thermal conductivity is low, and further modification is required. Summary of the Invention

[0005] The purpose of the present invention is to provide a highly heat-conductive and high-temperature-resistant heat shrinkable material and a preparation method thereof, which have good heat shrinkage performance and thermal conductivity, can maintain a shrunk state at 200 - 350 °C, and also have good corrosion resistance, radiation resistance, salt spray resistance, peel resistance, etc.

[0006] The present invention realizes the above purpose through the following technical solutions:

[0007] A highly heat-conductive and high-temperature-resistant heat shrinkable material, characterized in that it comprises the following raw materials in parts by weight: 78 - 94 parts of modified polyaryletherketone; 5 - 20 parts of modified boron nitride; 0.5 - 1 part of lubricant; 0.5 - 1 part of antioxidant; The modified polyaryletherketone has the following structural formula:

[0008]

[0009] X is the proportion of the biphenol polymerization monomer, and X is 0.1 - 0.5.

[0010] Furthermore, the modified boron nitride has a size of 20 - 500 nm and is one or more of spherical, flaky, and needle-like shapes.

[0011] A preparation method of a high thermal conductivity and high temperature resistant heat shrinkable material. Add the modified polyaryletherketone, modified boron nitride, lubricant, and antioxidant into a high-speed mixer and mix for 15 - 20 min to obtain a premix. Feed the premix into the main feeding port of a twin-screw extruder, extrude after melt blending, cool, and pelletize to obtain the high thermal conductivity and high temperature resistant heat shrinkable material.

[0012] Furthermore, dissolve biphenol, hydroquinone, and 4,4'-difluorobenzophenone in diphenyl sulfone in a nitrogen atmosphere in proportion, carry out a polycondensation reaction under the action of an alkali metal carbonate, discharge into distilled water, then pulverize, wash with a solvent to remove impurities, and finally dry at 120 °C to obtain the modified polyaryletherketone.

[0013] Furthermore, the alkali metal carbonate refers to one or more of sodium carbonate, potassium carbonate, cesium carbonate, lithium carbonate, and silver carbonate.

[0014] Furthermore, the washing solvent refers to one or more of ethanol, acetone, and distilled water.

[0015] Furthermore, the specific steps for preparing the modified boron nitride are as follows: Place the unmodified nano boron nitride in a vacuum plasma cleaner for surface treatment.

[0016] Furthermore, the atmosphere for the vacuum plasma cleaning treatment is any one or a mixture of two of oxygen (O 2 ) or argon (Ar).

[0017] Furthermore, the gas flow rate for the vacuum plasma cleaning treatment is 40 - 200 mL / min. If the gas flow rate is too high, the energy of the generated plasma radicals will be insufficient and functional groups cannot be effectively introduced. However, if the gas flow rate is too small, the activation degree of the material will be reduced.

[0018] Furthermore, the time for the vacuum plasma cleaning treatment is 4 - 30 min.

[0019] Compared with the prior art, the present invention copolymerizes and modifies traditional polyaryletherketone to regulate the aggregated state structure, improve the thermal shrinkage performance of the material, so that it still maintains excellent thermal shrinkage performance at 200-350 °C. At the same time, other excellent properties of polyaryletherketone can also be maintained at the original level. At the same time, plasma surface modification is carried out on nano boron nitride to improve its dispersibility in the polyaryletherketone matrix. A smaller amount of nano boron nitride can be used to increase the thermal conductivity of the material, which is conducive to the transfer of internal heat, and further improves the service temperature and service life of the thermal shrinkage material. In summary, the high thermal conductivity and high temperature resistant thermal shrinkage material described in the present invention greatly increases the service temperature of the thermal shrinkage material, expands its working environment and application fields, and makes up for the shortcomings of the existing thermal shrinkage materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is an optical picture of the high thermal conductivity and high temperature resistant thermal shrinkage materials of Examples 1-3. DETAILED DESCRIPTION OF THE INVENTION

[0021] The following are the raw materials specifically used in the examples and comparative examples of the present invention provided by relevant commercial suppliers or suppliers, but are not limited to the following raw materials: biphenol, Shanghai Merck Chemical Technology Co., Ltd.; hydroquinone, Shanghai Merck Chemical Technology Co., Ltd.; 4,4'-difluorobenzophenone, Aladdin Chemistry; diphenyl sulfone, J&K Scientific Ltd.; sodium carbonate, J&K Scientific Ltd.; potassium carbonate, J&K Scientific Ltd.; nano boron nitride, flaky, 20-500 nm, Aladdin Chemistry; acetone, Aladdin Chemistry; ethanol, Aladdin Chemistry; antioxidant 168, Beijing Jiyi Chemical Co., Ltd., lubricant EBS, Kao Corporation.

[0022] The present invention will be further described below through specific embodiments. The embodiments are only used to illustrate the present invention rather than to limit the present invention.

[0023] Example 1

[0024] A high thermal conductivity and high temperature resistant thermal shrinkage material, comprising the following raw materials in parts by weight: 94 parts of modified polyaryletherketone; 5 parts of modified boron nitride; 0.5 part of antioxidant 168 and 0.5 part of EBS;

[0025] Among them, the preparation method of the modified polyaryletherketone is as follows: add 53 g of hydroquinone, 22.5 g of biphenol, 132 g of 4,4'-difluorobenzophenone, 483 g of diphenyl sulfone, 80 g of sodium carbonate and 10 g of potassium carbonate. Under nitrogen conditions, heat and stir to melt at 180 °C, then mechanically stir at 220 °C for 1 h, mechanically stir at 250 °C for 1 h, mechanically stir at 280 °C for 1 h, mechanically stir at 300 °C for 1 h, and discharge in distilled water. After crushing, washing, filtering and drying, modified polyaryletherketone powder is obtained.

[0026] The preparation method of modified boron nitride is as follows: Put 10 g of nano-boron nitride into a vacuum plasma cleaner, set the cleaning time to 4 - 30 min, and the vacuum plasma cleaning atmosphere is one of the mixed gases of O 2 、Ar、O 2 and Ar, and adjust the gas flow rate to 40 - 200 mL / min.

[0027] The specific preparation method includes the following steps:

[0028] Add the modified polyaryletherketone, modified boron nitride, antioxidant 168, and EBS into a high-speed mixer and mix for 15 min until homogeneous to obtain a mixture; add the mixture into the main feeding port of a co-rotating twin-screw extruder, control the screw rotation speed at 300 r / min, the screw temperature at 300 - 380 °C, melt-blend and extrude, cool, and pelletize to obtain the high thermal conductivity and high temperature resistant heat shrinkable material.

[0029] Example 2

[0030] A high thermal conductivity and high temperature resistant heat shrinkable material, comprising the following raw materials in parts by weight: 89 parts of modified polyaryletherketone

[0031] ; 10 parts of modified boron nitride; 0.5 part of antioxidant 168 and 0.5 part of EBS;

[0032] Among them, the preparation method of the modified polyaryletherketone is as follows: Add 53 g of hydroquinone, 22.5 g of biphenol, 132 g of 4,4'-difluorobenzophenone, 483 g of diphenyl sulfone, 80 g of sodium carbonate, and 10 g of potassium carbonate. Under nitrogen conditions, heat and stir to melt at 180 °C, then mechanically stir at 220 °C for 1 h, 250 °C for 1 h, 280 °C for 1 h, 300 °C for 1 h, discharge in distilled water, and obtain modified polyaryletherketone powder through crushing, washing, filtering, and drying.

[0033] The preparation method of modified boron nitride is as follows: Put 10 g of nano-boron nitride into a vacuum plasma cleaner, set the cleaning time to 4 - 30 min, and the vacuum plasma cleaning atmosphere is one of the mixed gases of O 2 、Ar、O 2 and Ar, and adjust the gas flow rate to 40 - 200 mL / min.

[0034] The specific preparation method includes the following steps:

[0035] Add the modified polyaryletherketone, modified boron nitride, antioxidant 168, and EBS into a high-speed mixer and mix for 15 min until homogeneous to obtain a mixed material; add the mixed material into the main feeding port of a co-rotating twin-screw extruder, control the screw speed at 300 r / min, and the screw temperature at 300 - 380 °C, melt and co-mix and extrude, cool, and pelletize to obtain the high thermal conductivity and high temperature resistant heat shrinkable material.

[0036] Example 3

[0037] A high thermal conductivity and high temperature resistant heat shrinkable material, comprising the following raw materials in parts by weight: 84 parts of modified polyaryletherketone; 15 parts of modified boron nitride; 0.5 part of antioxidant 168, and 0.5 part of EBS;

[0038] Among them, the preparation method of the modified polyaryletherketone is as follows: add 53 g of hydroquinone, 22.5 g of biphenol, 132 g of 4,4'-difluorobenzophenone, 483 g of diphenyl sulfone, 80 g of sodium carbonate, and 10 g of potassium carbonate, heat and stir to melt under nitrogen conditions at 180 °C, then mechanically stir at 220 °C for 1 h, mechanically stir at 250 °C for 1 h, mechanically stir at 280 °C for 1 h, mechanically stir at 300 °C for 1 h, discharge in distilled water, and obtain modified polyaryletherketone powder after pulverization, washing, filtration, and drying.

[0039] The preparation method of the modified boron nitride is as follows: put 10 g of nano boron nitride into a vacuum plasma cleaner, set the cleaning time to 4 - 30 min, and the vacuum plasma cleaning atmosphere is one of the mixed gases of O 2 、Ar、O 2 and Ar, and adjust the gas flow rate to 40 - 200 mL / min.

[0040] The specific preparation method includes the following steps:

[0041] Add the modified polyaryletherketone, modified boron nitride, antioxidant 168, and EBS into a high-speed mixer and mix for 15 min until homogeneous to obtain a mixed material; add the mixed material into the main feeding port of a co-rotating twin-screw extruder, control the screw speed at 300 r / min, and the screw temperature at 300 - 380 °C, melt and co-mix and extrude, cool, and pelletize to obtain the high thermal conductivity and high temperature resistant heat shrinkable material.

[0042] The modified polyaryletherketone has the following structural formula:

[0043]

[0044] X is the proportion of the biphenol polymerization monomer, and X is 0.1 - 0.5;

[0045] The polymerization preparation process of the modified polyaryletherketone is as follows:

[0046]

[0047] Comparative Example 1

[0048] Comparative Example 1 is unmodified polyaryletherketone, including the following raw materials in parts by weight: 99 parts of commercially available polyaryletherketone; 0.5 part of antioxidant 168 and 0.5 part of EBS; The specific preparation method is the same as that of Example 1.

[0049] Comparative Example 2

[0050] Comparative Example 2 is modified polyaryletherketone, including the following raw materials in parts by weight: 99 parts of modified polyaryletherketone; 0.5 part of antioxidant 168 and 0.5 part of EBS; The specific preparation method is the same as that of Example 1.

[0051] Comparative Example 3 is the comparative example of Example 3, including the following raw materials in parts by weight: 84 parts of modified polyaryletherketone; 15 parts of unmodified boron nitride; 0.5 part of antioxidant 168 and 0.5 part of EBS; The specific preparation method is the same as that of Example 3.

[0052] The high thermal conductivity and high temperature resistant heat shrinkable materials prepared in the above Examples 1 to 3 and Comparative Examples 1 to 3 were

[0053] dried in a forced air oven at 100-110 °C for 6-8 hours, and then the dried particles were molded into samples on a hot press, and then the heat shrinkage performance and thermal conductivity of the above samples were tested. Table 1 shows the technical solutions (parts by weight) and test results of the examples and comparative examples.

[0054] Table 1 Technical solutions (parts by weight) and test results of Examples 1 to 3 and Comparative Examples 1 to 3

[0055]

[0056] As can be seen from Table 1, compared with Comparative Example 1, Comparative Example 2 shows that after the polyaryletherketone is modified, its heat shrinkage performance is significantly improved. Compared with Comparative Example 2, Examples 1-3 can improve the thermal conductivity of the material by introducing modified boron nitride, and the heat shrinkage performance of the material is not greatly affected. Compared with Comparative Example 3, Example 3 shows that the modified boron nitride has a smaller improvement in the thermal conductivity of the material and a smaller impact on the heat shrinkage performance of the material.

[0057] The present invention copolymerizes and modifies traditional polyaryletherketone to regulate the aggregated state structure, improve the thermal shrinkage performance of the material, so that it still maintains excellent thermal shrinkage performance at 200 - 350 °C, and at the same time, other excellent properties of polyaryletherketone can also maintain the original level; meanwhile, plasma surface modification is carried out on nano boron nitride to improve its dispersion in the polyaryletherketone matrix, and the thermal conductivity of the material can be improved with a smaller amount of nano boron nitride, which is beneficial to the transfer of internal heat and further improves the service temperature and service life of the thermal shrinkage material. In summary, the high thermal conductivity and high temperature resistant thermal shrinkage material described in the present invention greatly increases the service temperature of the thermal shrinkage material, expands its working environment and application fields, and makes up for the shortcomings of existing thermal shrinkage materials.

[0058] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit the protection scope of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A high thermal conductivity and high temperature resistant heat shrinkable material, characterized in that: The invention comprises the following raw materials in parts by weight: 78-94 parts of modified polyaryletherketone; 5-20 parts of modified boron nitride; 0.5-1 parts of lubricant; and 0.5-1 parts of antioxidant. The modified polyaryletherketone has the following structural formula: X is the proportion of biphenol polymerization monomer, and X is 0.1-0.

5.

2. The high thermal conductivity and high temperature resistant heat shrinkable material according to claim 1, characterized in that: The modified boron nitride is characterized by being 20-500nm in size and having a shape of one or more of sphere, flake, and needle.

3. A method for preparing a high thermal conductivity and high temperature resistant heat shrinkable material as claimed in claim 1 or 2, characterized in that: The modified polyaryletherketone, modified boron nitride, lubricant and antioxidant are added to a high-speed mixer and mixed for 15-20 minutes to obtain a premix; the premix is ​​added to the main feeding port of a twin-screw extruder, melt-blended and then extruded, cooled and pelletized to obtain the high thermal conductivity and high temperature resistant heat shrinkable material.

4. The preparation method according to claim 3, characterized in that: The specific steps of preparing the modified polyaryletherketone by polymerization are as follows: dissolving biphenol, hydroquinone and 4,4'-difluorobenzophenone in diphenyl sulfone in proportion under a nitrogen atmosphere, causing polycondensation reaction under the action of alkali metal carbonate, discharging the material in distilled water, then crushing it, washing it with a solvent to remove impurities, and finally drying it at 120°C to obtain the modified polyaryletherketone.

5. The preparation method according to claim 4, characterized in that: The alkali metal carbonate refers to one or more of sodium carbonate, potassium carbonate, cesium carbonate, lithium carbonate, and silver carbonate.

6. The preparation method according to claim 4, characterized in that: The washing solvent is one or more of ethanol, acetone and distilled water.

7. The preparation method according to claim 4, characterized in that: The specific steps of preparing the modified boron nitride are: placing unmodified nano boron nitride in a vacuum plasma cleaning machine for surface treatment.

8. The preparation method according to claim 7, characterized in that: The atmosphere of the vacuum plasma cleaning process is any one of oxygen (O2) or argon (Ar) or a mixture of the two.

9. The preparation method according to claim 7, characterized in that: The gas flow rate of the vacuum plasma cleaning treatment is 40-200 mL / min; if the gas flow rate is too high, the energy of the generated plasma radicals will be insufficient and the functional groups cannot be effectively introduced, but if the gas flow rate is too low, the activation degree of the material will be reduced.

10. The preparation method according to claim 7, characterized in that: The vacuum plasma cleaning treatment lasts for 4-30 minutes.

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