A TPX / PBT composite release film and its preparation method

Abstract

This invention provides a TPX / PBT composite release film, comprising a TPX film layer and a PBT film layer, which are composited by electrospun film. The electrospun film is a SiC electrospun film with a porosity of 85-95% and a thickness of 20-30 μm. The TPX film has a thickness of 150-180 μm, and the PBT film has a thickness of 120-150 μm. The TPX film layer and the PBT film layer contain tendril-like thermally conductive particles of different or the same particle size. This invention employs a double-layer composite TPX / PBT film with different release forces on both sides. This double-sided release film can be used as a carrier for the production, processing, and transfer of flexible printed circuit boards, polarizer protective films in the panel industry, multilayer ceramic capacitors, and stacked built-in antennas.

Description

Technical Field

[0001] This invention relates to the field of release films, specifically to a TPX / PBT composite release film and its preparation method. Background Technology

[0002] Release film, also known as peeling film, release film, separation film, adhesive barrier film, thin film, plastic film, masking film, silicone film, silicone paper, anti-stick film, slip film, thinner paper, release paper, silicon film, release film, release. Double-sided release film is a special type of release film that has release properties on both sides.

[0003] Polyester-based films are commonly used as the base film for release films. They are typically made from polyester chips as the main raw material, melt-extruded into thick sheets, and then stretched longitudinally and transversely, heat-set, and wound into thin films. Due to adhesion between the base films during the winding and slitting process, as well as in subsequent packaging, transportation, and use, many problems can arise. Therefore, a certain amount of anti-adhesion particles are usually added to the surface of the polyester base film. Currently, the anti-adhesion particles in polyester are mainly inorganic, generally selected from one or more of silica, calcium carbonate, barium sulfate, titanium dioxide, mica, and kaolin. Currently, silica synthesized by the gel method is the preferred anti-adhesion particle due to its low price and good anti-adhesion effect. The low temperature resistance of ordinary polyester base films leads to deformation after heating. To improve the temperature resistance of the base film, it is necessary to reduce the thermal shrinkage in the longitudinal and transverse directions. The traditional method is to increase the heat setting time of the base film, but this also reduces the longitudinal and transverse strength of the base film, which is detrimental to subsequent processing and use.

[0004] TPX release film, short for thermoplastic polyolefin release film, is a high-performance thermoplastic material widely used in electronics, electrical engineering, automotive, packaging, and other fields due to its excellent physical properties, chemical stability, and ease of processing. In particular, TPX release film plays a crucial role in the manufacturing process of flexible semiconductor circuit boards.

[0005] TPX release film possesses excellent transparency, gloss, and mechanical strength. It also exhibits superior heat resistance, remaining stable at high temperatures. In flexible circuit board manufacturing, TPX release film is commonly used as a cover layer or substrate to protect circuits from physical damage and environmental influences. Utilizing its thermoplastic properties, TPX release film can be laminated with other materials through hot pressing and other methods to form multilayer composite materials.

[0006] As electronic devices become smaller and more flexible, TPX release films are constantly being optimized to adapt to more sophisticated circuit designs and higher performance requirements; the long-term stability of the material and its performance in extreme environments remain key research areas. This invention combines TPX and PBT to prepare a release film with release properties on both sides, to meet the requirements of use under more demanding conditions. Summary of the Invention

[0007] The technical problem to be solved: The purpose of this invention is to provide a TPX / PBT composite release film, which has release effect on both sides and excellent temperature resistance.

[0008] Technical solution: A TPX / PBT composite release film, wherein the release film comprises a TPX film layer and a PBT film layer.

[0009] Preferably, the TPX membrane and PBT membrane are composited by electrospun membrane, wherein the electrospun membrane is a SiC electrospun membrane with a porosity of 85-95% and a thickness of 20-30 μm, the TPX membrane has a thickness of 150-180 μm, and the PBT membrane has a thickness of 120-150 μm. The TPX membrane layer and the PBT membrane layer contain tendril-like thermally conductive particles of different or the same particle size.

[0010] Preferably, the method for preparing the whisker-like thermally conductive particles includes the following steps:

[0011] S11. Dissolve cellulose in a mixed solvent of sodium hydroxide, urea and water in a mass ratio of 7:12:81 to obtain a cellulose solution with a concentration of 5.2-6.5 wt%.

[0012] S12. Add calcium carbonate and carbon nanotubes to the cellulose solution, with a mass-to-volume ratio of calcium carbonate, carbon nanotubes and cellulose solution of 2-4 g: 3.5-5 g: 100 mL, to obtain a mixed cellulose solution;

[0013] S13. Divide the mixed cellulose solution into two portions. Using the mixed cellulose solution as the aqueous phase, add the two portions of the solution dropwise to the oil phases of Tween 80, Span 80 and liquid paraffin, respectively. Stir at different or the same speeds and add 2-epoxypropane. After the reaction is complete, add ethanol, filter and dry to obtain cellulose microspheres of different or the same particle size.

[0014] S14. Two different or the same size cellulose microspheres are added to a dilute hydrochloric acid solution, stirred and reacted, filtered and dried to obtain porous cellulose microspheres;

[0015] S15. Two porous cellulose microspheres of different or the same particle size are added to an ethylene glycol solution containing PVP, mixed and stirred evenly, and then an ethylene glycol solution containing silver nitrate is added dropwise to react. After the reaction is completed, the mixture is filtered to obtain spiky spherical silver / carbon nanotube / cellulose composite microspheres of different particle sizes.

[0016] Preferably, in step S13, the mixed cellulose solution is divided into two parts. The mixed cellulose solution is used as the aqueous phase. The two parts of the solution are added dropwise to the oil phases of Tween 80, Span 80 and liquid paraffin, respectively. The mixtures are stirred at speeds of 1200-1600 r / min and 1500-1800 r / min, respectively. The volume ratio of the aqueous phase to the oil phase is 4-6:1. 2-Epoxypropane is added. After the reaction is complete, ethanol is added. The mixture is filtered and dried to obtain two cellulose microspheres with different or the same particle size.

[0017] Preferably, in step S15, the mass-to-volume ratio of porous cellulose microspheres, PVP, silver nitrate, and ethylene glycol is 20-30g:1-2g:3-6g:200-300mL.

[0018] The above-mentioned method for preparing the TPX / PBT composite release film includes the following steps:

[0019] S1. Two types of spiky spherical silver / carbon nanotube / fiber microspheres with different or the same particle size are added to TPX and PBT respectively, mixed evenly, and then granulated by a twin-screw extruder to prepare modified TPX particles and PBT particles.

[0020] S2. Modified TPX particles and PBT particles are cast into films using a single-screw extruder to obtain TPX films and PBT films;

[0021] S3. Stack the three layers of film in sequence: TPX film, SiC electrospun film and PBT film. Heat the SiC electrospun film and then composite it under pressure to obtain the TPX / PBT composite release film.

[0022] Preferably, in step S1, the mass ratio of spiky silver / carbon nanotubes / fiber microspheres to TPX is 0.2-0.5:10, and the mass ratio of spiky silver / carbon nanotubes / fiber microspheres to PBT is 0.2-0.4:10.

[0023] Preferably, in step S3, the heating temperature of the SiC electrospun film is 220-250℃, and the pressure applied is 4-8 N / cm. 2 .

[0024] Beneficial effects: The TPX / PBT composite release film of the present invention has the following advantages:

[0025] This invention uses a double-layer composite TPX / PBT film. The release forces on both sides of the two release films are different. The double-sided release film can be used for flexible printed circuit boards, polarizer protective films in the panel industry, carriers for the production, processing and transfer of multilayer ceramic capacitors and stacked built-in antennas, etc.

[0026] The release film provided by this invention incorporates spiky silver / carbon nanotube / fiber microspheres. These microspheres serve a dual purpose: First, they form slight protrusions on the surface of the release film, reducing the contact area between the release film and other contact components, thereby improving its release properties. They also exhibit good release performance at higher temperatures, and microspheres of different sizes can be designed to meet the requirements of various application conditions. Second, the microspheres contain carbon nanotubes and nano-silver tendrils, which can form thermally conductive pathways within the release film, enhancing its thermal conductivity.

[0027] In this invention, an electrospun SiC film is added between the two release films, which results in a base film with a lower thermal shrinkage rate under the same processing conditions. At the same time, the SiC film increases the thermal conductivity of the release film. Detailed Implementation

[0028] The present invention will be further described below with reference to embodiments. These embodiments are illustrative of the present invention, but the present invention is not limited to these embodiments:

[0029] Example 1

[0030] The method for preparing tendril-like thermally conductive particles includes the following steps:

[0031] S11. Dissolve cellulose in a mixed solvent of sodium hydroxide, urea and water in a mass ratio of 7:12:81 to obtain a cellulose solution with a concentration of 5.2 wt%.

[0032] S12. Add calcium carbonate and carbon nanotubes to the cellulose solution. The mass-volume ratio of calcium carbonate, carbon nanotubes and cellulose solution is 2g:3.5g:100mL to obtain a mixed cellulose solution.

[0033] S13. Divide the mixed cellulose solution into two portions. Using the mixed cellulose solution as the aqueous phase, add the two portions of the solution dropwise to the oil phases of Tween 80, Span 80 and liquid paraffin, respectively. Stir at speeds of 1200 r / min and 1600 r / min, respectively. The volume ratio of the aqueous phase to the oil phase is 4:1. Add 2-epoxypropane. After the reaction is complete, add ethanol. Filter and dry to obtain cellulose microspheres with two different particle sizes.

[0034] S14. Two different cellulose microspheres were added to a 0.1 mol / L dilute hydrochloric acid solution, stirred and reacted, filtered and dried to obtain porous cellulose microspheres;

[0035] S15. Two porous cellulose microspheres of different or the same particle size were added to an ethylene glycol solution containing PVP. After mixing and stirring evenly, an ethylene glycol solution containing silver nitrate was added dropwise for reaction. The mass-volume ratio of porous cellulose microspheres, PVP, silver nitrate and ethylene glycol was 20g:1g:3g:200mL. After the reaction was completed, the microspheres were filtered to obtain spiky spherical silver / carbon nanotube / cellulose composite microspheres of different particle sizes.

[0036] Example 2

[0037] The method for preparing tendril-like thermally conductive particles includes the following steps:

[0038] S11. Dissolve cellulose in a mixed solvent of sodium hydroxide, urea and water in a mass ratio of 7:12:81 to obtain a cellulose solution with a concentration of 6.5 wt%.

[0039] S12. Add calcium carbonate and carbon nanotubes to the cellulose solution. The mass-volume ratio of calcium carbonate, carbon nanotubes and cellulose solution is 4g:5g:100mL to obtain a mixed cellulose solution.

[0040] S13. Divide the mixed cellulose solution into two portions. Using the mixed cellulose solution as the aqueous phase, add the two portions of the solution dropwise to the oil phases of Tween 80, Span 80 and liquid paraffin, respectively. Stir at speeds of 1500 r / min and 1800 r / min, respectively. The volume ratio of the aqueous phase to the oil phase is 6:1. Add 2-epoxypropane. After the reaction is complete, add ethanol. Filter and dry to obtain cellulose microspheres with two different particle sizes.

[0041] S14. Two different cellulose microspheres were added to a 0.1 mol / L dilute hydrochloric acid solution, stirred and reacted, filtered and dried to obtain porous cellulose microspheres;

[0042] S15. Two porous cellulose microspheres of different or the same particle size were added to an ethylene glycol solution containing PVP. After mixing and stirring evenly, an ethylene glycol solution containing silver nitrate was added dropwise for reaction. The mass-volume ratio of porous cellulose microspheres, PVP, silver nitrate and ethylene glycol was 30g:2g:6g:300mL. After the reaction was completed, the microspheres were filtered to obtain spiky spherical silver / carbon nanotube / cellulose composite microspheres of different particle sizes.

[0043] Example 3

[0044] The method for preparing the whisker-like thermally conductive particles includes the following steps:

[0045] S11. Dissolve cellulose in a mixed solvent of sodium hydroxide, urea and water in a mass ratio of 7:12:81 to obtain a cellulose solution with a concentration of 6wt%.

[0046] S12. Add calcium carbonate and carbon nanotubes to the cellulose solution. The mass-volume ratio of calcium carbonate, carbon nanotubes and cellulose solution is 3g:4g:100mL to obtain a mixed cellulose solution.

[0047] S13. Divide the mixed cellulose solution into two portions. Using the mixed cellulose solution as the aqueous phase, add the two portions of the solution dropwise to the oil phases of Tween 80, Span 80 and liquid paraffin, respectively. Stir at speeds of 1200 r / min and 1600 r / min, respectively. The volume ratio of the aqueous phase to the oil phase is 5:1. Add 2-epoxypropane. After the reaction is complete, add ethanol. Filter and dry to obtain two different particle sizes of cellulose microspheres. The two different particle sizes of cellulose microspheres are designated as MCBs-1 and MCB-2, respectively.

[0048] S14. Two different or the same size cellulose microspheres are added to a dilute hydrochloric acid solution, stirred and reacted, filtered and dried to obtain porous cellulose microspheres;

[0049] S15. Two porous cellulose microspheres of different or the same particle size were added to an ethylene glycol solution containing PVP. After mixing and stirring evenly, an ethylene glycol solution containing silver nitrate was added dropwise for reaction. The mass-volume ratio of porous cellulose microspheres, PVP, silver nitrate and ethylene glycol was 25g:1.5g:5g:240mL. After the reaction was completed, the microspheres were filtered to obtain spiky silver / carbon nanotube / cellulose composite microspheres of different particle sizes. The two spiky silver / carbon nanotube / cellulose composite microspheres of different particle sizes were designated as Ag-MCBs-1 and Ag-MCB-2, respectively.

[0050] Example 4

[0051] The difference between Example 4 and Example 3 lies in the different stirring speeds in step S13. In step S13: the mixed cellulose solution is divided into two parts, with the mixed cellulose solution as the aqueous phase. The two parts of the solution are added dropwise to the oil phases of Tween 80, Span 80 and liquid paraffin, respectively, and stirred at speeds of 1300 r / min and 1680 r / min, respectively. The volume ratio of the aqueous phase to the oil phase is 5:1, and 2-epoxypropane is added. After the reaction is complete, ethanol is added, and the mixture is filtered and dried to obtain two different cellulose microspheres with different particle sizes. The two different cellulose microspheres with different particle sizes are designated as MCBs-1 and MCB-2, respectively.

[0052] In step S15: the two types of spiky spherical silver / carbon nanotube / cellulose composite microspheres with different particle sizes are designated as Ag-MCBs-1 and Ag-MCB-2, respectively.

[0053] Example 5

[0054] The difference between Example 5 and Example 3 is that the stirring speed is different in step S13. In step S13: the mixed cellulose solution is divided into two parts, and the mixed cellulose solution is used as the aqueous phase. The two parts of the solution are added dropwise to the oil phases of Tween 80, Span 80 and liquid paraffin, respectively, and stirred at speeds of 1350 r / min and 1750 r / min, respectively. The volume ratio of the aqueous phase to the oil phase is 5:1, and 2-epoxypropane is added. After the reaction is completed, ethanol is added, and the mixture is filtered and dried to obtain two different cellulose microspheres with different particle sizes. The two different cellulose microspheres with different particle sizes are named MCBs-1 and MCB-2, respectively.

[0055] In step S15: the two types of spiky spherical silver / carbon nanotube / cellulose composite microspheres with different particle sizes are designated as Ag-MCBs-1 and Ag-MCB-2, respectively.

[0056] Example 6

[0057] The difference between Example 6 and Example 3 is that the stirring speed is different in step S13. In step S13: the mixed cellulose solution is divided into two parts, and the mixed cellulose solution is used as the aqueous phase. The two parts of the solution are added dropwise to the oil phases of Tween 80, Span 80 and liquid paraffin, respectively, and stirred at speeds of 1500 r / min and 1800 r / min, respectively. The volume ratio of the aqueous phase to the oil phase is 5:1, and 2-epoxypropane is added. After the reaction is completed, ethanol is added, and the mixture is filtered and dried to obtain two different cellulose microspheres with different particle sizes. The two different cellulose microspheres with different particle sizes are named MCBs-1 and MCB-2, respectively.

[0058] In step S15: the two types of spiky spherical silver / carbon nanotube / cellulose composite microspheres with different particle sizes are designated as Ag-MCBs-1 and Ag-MCB-2, respectively.

[0059] Example 7

[0060] The difference between Example 6 and Example 3 is that the stirring speed is different in step S13. In step S13: the mixed cellulose solution is used as the aqueous phase. The aqueous phase solution is added dropwise to the oil phase of Tween 80, Span 80 and liquid paraffin. The mixture is stirred at a speed of 1600 r / min. The volume ratio of the aqueous phase to the oil phase is 5:1. 2-epoxypropane is added. After the reaction is completed, ethanol is added. The mixture is filtered and dried to obtain cellulose microspheres, which are denoted as MCBs-1.

[0061] In step S15: the spiky silver / carbon nanotube / cellulose composite microspheres are respectively designated as Ag-MCBs-1.

[0062] Table 1 shows the particle size of cellulose microspheres.

[0063] MCBs-1 particle size / um MCBs-2 particle size / um Example 3 75 44 Example 4 67 40 Example 5 62 36 Example 6 53 32 Example 7 43 /

[0064] Table 2 shows the particle size of the silver / carbon nanotube / cellulose composite microspheres.

[0065] Ag-MCBs-1 particle size / um Ag-MCBs-2 particle size / um Example 3 80 48 Example 4 71 46 Example 5 67 41 Example 6 59 36 Example 7 47 /

[0066] Example 8

[0067] A TPX / PBT composite release film, the release film comprising a TPX film layer and a PBT film layer, wherein the TPX film and the PBT film are composited by electrospun film, and the electrospun film is a SiC electrospun film with a porosity of 85% and a thickness of 20 μm.

[0068] The preparation method of the above-mentioned TPX / PBT composite release film includes the following steps:

[0069] S1. Add Ag-MCBs-1 prepared in Example 3 to TPX and Ag-MCBs-2 to PBT. The mass ratio of Ag-MCBs-1 to TPX is 0.2:10, and the mass ratio of Ag-MCBs-2 to PBT is 0.2:10. After mixing evenly, add the mixture to a twin-screw extruder for granulation to prepare modified TPX particles and PBT particles.

[0070] S2. Modified TPX particles and PBT particles are cast into films using a single screw extruder to obtain a TPX film with a thickness of 180 μm and a PBT film with a thickness of 150 μm.

[0071] S3. A TPX film, a SiC electrospun film, and a PBT film are stacked sequentially. The SiC electrospun film is heated to 220℃ and then laminated under pressure of 4 N / cm. 2 TPX / PBT composite release film was obtained.

[0072] Example 9

[0073] A TPX / PBT composite release film, the release film comprising a TPX film layer and a PBT film layer, wherein the TPX film and the PBT film are composited by electrospun film, and the electrospun film is a SiC electrospun film with a porosity of 95% and a thickness of 30 μm.

[0074] The preparation method of the above-mentioned TPX / PBT composite release film includes the following steps:

[0075] S1. Add Ag-MCBs-1 prepared in Example 4 to TPX and Ag-MCBs-2 to PBT. The mass ratio of Ag-MCBs-1 to TPX is 0.3:10, and the mass ratio of Ag-MCBs-2 to PBT is 0.3:10. After mixing evenly, add the mixture to a twin-screw extruder for granulation to prepare modified TPX particles and PBT particles.

[0076] S2. Modified TPX particles and PBT particles are cast into films using a single-screw extruder to obtain a TPX film with a thickness of 170 μm and a PBT film with a thickness of 140 μm.

[0077] S3. A TPX film, a SiC electrospun film, and a PBT film are stacked sequentially. The SiC electrospun film is heated to 250℃ and then laminated under pressure of 8 N / cm. 2 TPX / PBT composite release film was obtained.

[0078] Example 10

[0079] A TPX / PBT composite release film, the release film comprising a TPX film layer and a PBT film layer, wherein the TPX film and the PBT film are composited by electrospun film, and the electrospun film is a SiC electrospun film with a porosity of 85% and a thickness of 20 μm.

[0080] The preparation method of the above-mentioned TPX / PBT composite release film includes the following steps:

[0081] S1. Add Ag-MCBs-1 prepared in Example 5 to TPX and Ag-MCBs-2 to PBT. The mass ratio of Ag-MCBs-1 to TPX is 0.4:10 and the mass ratio of Ag-MCBs-2 to PBT is 0.3:10. After mixing evenly, add the mixture to a twin-screw extruder for granulation to prepare modified TPX particles and PBT particles.

[0082] S2. Modified TPX particles and PBT particles are cast into films using a single screw extruder to obtain a TPX film with a thickness of 160 μm and a PBT film with a thickness of 130 μm.

[0083] S3. A TPX film, a SiC electrospun film, and a PBT film are stacked sequentially. The SiC electrospun film is heated to 230℃ and then laminated under pressure of 6 N / cm. 2 TPX / PBT composite release film was obtained.

[0084] Example 11

[0085] A TPX / PBT composite release film, the release film comprising a TPX film layer and a PBT film layer, the TPX film and PBT film being composited by an electrospun film, the electrospun film being a SiC electrospun film with a porosity of 90% and a thickness of 25µm;

[0086] The preparation method of the above-mentioned TPX / PBT composite release film includes the following steps:

[0087] S1. Add Ag-MCBs-1 prepared in Example 6 to TPX and Ag-MCBs-2 to PBT. The mass ratio of Ag-MCBs-1 to TPX is 0.5:10 and the mass ratio of Ag-MCBs-2 to PBT is 0.4:10. After mixing evenly, add the mixture to a twin-screw extruder for granulation to prepare modified TPX particles and PBT particles.

[0088] S2. Modified TPX particles and PBT particles are cast into films using a single screw extruder to obtain a TPX film with a thickness of 150 μm and a PBT film with a thickness of 120 μm.

[0089] S3. A TPX film, a SiC electrospun film, and a PBT film are stacked sequentially. The SiC electrospun film is heated to 230℃ and then laminated under pressure of 6 N / cm. 2 TPX / PBT composite release film was obtained.

[0090] Example 12

[0091] A TPX / PBT composite release film, the release film comprising a TPX film layer and a PBT film layer, the TPX film and PBT film being composited by an electrospun film, the electrospun film being a SiC electrospun film with a porosity of 90% and a thickness of 25µm;

[0092] The preparation method of the above-mentioned TPX / PBT composite release film includes the following steps:

[0093] S1. The Ag-MCBs-1 prepared in Example 7 was added to TP and PBT. The mass ratio of Ag-MCBs-1 to TPX was 0.5:10, and the mass ratio of Ag-MCBs-1 to PBT was 0.4:10. After being mixed evenly, the mixture was added to a twin-screw extruder for granulation to prepare modified TPX particles and PBT particles.

[0094] S2. Modified TPX particles and PBT particles are cast into films using a single screw extruder to obtain a TPX film with a thickness of 150 μm and a PBT film with a thickness of 120 μm.

[0095] S3. A TPX film, a SiC electrospun film, and a PBT film are stacked sequentially. The SiC electrospun film is heated to 230℃ and then laminated under pressure of 6 N / cm. 2 TPX / PBT composite release film was obtained.

[0096] Comparative Example 1

[0097] A TPX / PBT composite release film, the release film comprising a TPX film layer and a PBT film layer, wherein the TPX film and the PBT film are laminated by hot pressing;

[0098] The preparation method of the above-mentioned TPX / PBT composite release film includes the following steps:

[0099] S1. Add Ag-MCBs-1 prepared in Example 6 to TPX and Ag-MCBs-2 to PBT. The mass ratio of Ag-MCBs-1 to TPX is 0.5:10 and the mass ratio of Ag-MCBs-2 to PBT is 0.4:10. After mixing evenly, add the mixture to a twin-screw extruder for granulation to prepare modified TPX particles and PBT particles.

[0100] S2. Modified TPX particles and PBT particles are cast into films using a single screw extruder to obtain a TPX film with a thickness of 150 μm and a PBT film with a thickness of 120 μm.

[0101] S3. Stack the TPX film and PBT film sequentially, and then hot-press them together at a temperature of 200℃ and a pressure of 6 N / cm. 2 TPX / PBT composite release film was obtained.

[0102] Comparative Example 2

[0103] A TPX / PBT composite release film, the release film comprising a TPX film layer and a PBT film layer, the TPX film and PBT film being composited by an electrospun film, the electrospun film being a SiC electrospun film with a porosity of 90% and a thickness of 25µm;

[0104] The preparation method of the above-mentioned TPX / PBT composite release film includes the following steps:

[0105] S1. The MCBs-1 prepared in Example 6 was added to TPX, and the MCBs-2 was added to PBT. The mass ratio of MCBs-1 to TPX was 0.5:10, and the mass ratio of MCBs-2 to PBT was 0.4:10. After mixing evenly, the mixture was added to a twin-screw extruder for granulation to prepare modified TPX particles and PBT particles.

[0106] S2. Modified TPX particles and PBT particles are cast into films using a single screw extruder to obtain a TPX film with a thickness of 150 μm and a PBT film with a thickness of 120 μm.

[0107] S3. A TPX film, a SiC electrospun film, and a PBT film are stacked sequentially. The SiC electrospun film is heated to 230℃ and then laminated under pressure of 6 N / cm. 2TPX / PBT composite release film was obtained.

[0108] Comparative Example 3

[0109] A TPX / PBT composite release film, the release film comprising a TPX film layer and a PBT film layer, the TPX film and PBT film being composited by an electrospun film, the electrospun film being a SiC electrospun film with a porosity of 90% and a thickness of 25µm;

[0110] The preparation method of the above-mentioned TPX / PBT composite release film includes the following steps:

[0111] S1. Ag-MCBs were added to TPX and PBT respectively, with the mass ratio of Ag-MCBs to TPX being 0.5:10 and the mass ratio of Ag-MCBs to PBT being 0.4:10. After being mixed evenly, the mixture was fed into a twin-screw extruder for granulation to prepare modified TPX particles and PBT particles.

[0112] S2. Modified TPX particles and PBT particles are cast into films using a single screw extruder to obtain a TPX film with a thickness of 150 μm and a PBT film with a thickness of 120 μm.

[0113] S3. A TPX film, a SiC electrospun film, and a PBT film are stacked sequentially. The SiC electrospun film is heated to 230℃ and then laminated under pressure of 6 N / cm. 2 A TPX / PBT composite release film was obtained.

[0114] The preparation method of the Ag-MCBs includes the following steps:

[0115] S11. Dissolve cellulose in a mixed solvent of sodium hydroxide, urea and water in a mass ratio of 7:12:81 to obtain a cellulose solution with a concentration of 6wt%.

[0116] S12. Add calcium carbonate and carbon nanotubes to the cellulose solution. The mass-volume ratio of calcium carbonate, carbon nanotubes and cellulose solution is 3g:4g:100mL to obtain a mixed cellulose solution.

[0117] S13. Using a mixed cellulose solution as the aqueous phase, the aqueous solution was added dropwise to the oil phases of Tween 80, Span 80 and liquid paraffin, respectively. The mixture was stirred at a speed of 500 r / min, with a volume ratio of aqueous phase to oil phase of 5:1. 2-Epoxypropane was added, and after the reaction was completed, ethanol was added. The mixture was filtered and dried to obtain cellulose microspheres, denoted as MCBs.

[0118] S14. Add cellulose microspheres to a dilute hydrochloric acid solution, stir to react, filter and dry to obtain porous cellulose microspheres;

[0119] S15. Porous cellulose microspheres were added to an ethylene glycol solution containing PVP, and after mixing and stirring evenly, an ethylene glycol solution containing silver nitrate was added dropwise for reaction. The mass-volume ratio of porous cellulose microspheres, PVP, silver nitrate and ethylene glycol was 25g:1.5g:5g:240mL. After the reaction was completed, the mixture was filtered to obtain spiky silver / carbon nanotube / cellulose composite microspheres, denoted as Ag-MCBs.

[0120] Comparative Example 4

[0121] A TPX / PBT composite release film, the release film comprising a TPX film layer and a PBT film layer, the TPX film and PBT film being composited by an electrospun film, the electrospun film being a SiC electrospun film with a porosity of 90% and a thickness of 25µm;

[0122] The preparation method of the above-mentioned TPX / PBT composite release film includes the following steps:

[0123] S1. Add silver nanowires to TPX and PBT respectively, with a mass ratio of silver nanowires to TPX of 0.5:10 and a mass ratio of silver nanowires to PBT of 0.4:10. After mixing evenly, add to a twin-screw extruder for granulation to prepare modified TPX particles and PBT particles.

[0124] S2. Modified TPX particles and PBT particles are cast into films using a single screw extruder to obtain a TPX film with a thickness of 150 μm and a PBT film with a thickness of 120 μm.

[0125] S3. A TPX film, a SiC electrospun film, and a PBT film are stacked sequentially. The SiC electrospun film is heated to 230℃ and then laminated under pressure of 6 N / cm. 2 A TPX / PBT composite release film was obtained.

[0126] The method for preparing the silver nanowires includes the following steps:

[0127] After mixing and stirring the PVP solution in ethylene glycol, a silver nitrate-containing ethylene glycol solution was added dropwise to react. The mass-volume ratio of PVP, silver nitrate, and ethylene glycol was 1 g: 3 g: 100 mL. After the reaction was completed, the nanowires were obtained by filtration.

[0128] Performance characterization:

[0129] Peel strength test: According to the test method in GB / T 2792-1998 "Test method for 180° peel strength of pressure sensitive adhesive tape", double-sided optical tape was attached to the test steel plate for testing, and peeling was performed at a test speed of 300mm / min. The test results were recorded.

[0130] Heat shrinkage rate and heat resistance: According to GB / T 33377-2016, the longitudinal and transverse heat shrinkage rates were tested using a micrometer and a forced-air constant temperature drying oven. The test conditions were 150 ℃ for 30 minutes, with 3 samples tested in each direction, and the average value was calculated.

[0131] Table 3

[0132]

[0133] Table 4

[0134]

[0135] Obviously, the above embodiments are merely examples for clarity of explanation and are not intended to limit the implementation methods. Those skilled in the art will readily appreciate that other variations or modifications based on the above descriptions are possible. It is not necessary and impossible to enumerate all implementation methods here. Obvious variations or modifications arising therefrom remain within the scope of protection of the present invention.

Claims

1. A TPX / PBT composite release film, characterized in that: The release membrane includes a TPX film layer and a PBT film layer, which are composited by electrospun film. The electrospun film is a SiC electrospun film with a porosity of 85-95%. The TPX film layer and the PBT film layer contain tendril-shaped thermally conductive particles. The particle size of the tendril-shaped thermally conductive particles in the TPX film layer may be the same as or different from the particle size of the tendril-shaped thermally conductive particles in the PBT film layer. The method for preparing the whisker-like thermally conductive particles includes the following steps: S11. Dissolve cellulose in a mixed solvent of sodium hydroxide, urea and water in a mass ratio of 7:12:81 to obtain a cellulose solution with a concentration of 5.2-6.5 wt%. S12. Add calcium carbonate and carbon nanotubes to the cellulose solution, with a mass-to-volume ratio of calcium carbonate, carbon nanotubes and cellulose solution of 2-4 g: 3.5-5 g: 100 mL, to obtain a mixed cellulose solution; S13. Divide the mixed cellulose solution into two portions. Using the mixed cellulose solution as the aqueous phase, add the two portions of the solution dropwise to the oil phases of Tween 80, Span 80, and liquid paraffin, respectively. The volume ratio of the aqueous phase to the oil phase is 4-6:

1. Stir at different or the same speeds and add 2-epoxypropane. After the reaction is complete, add ethanol, filter and dry to obtain cellulose microspheres of different or the same particle size. When stirring at different speeds, the speeds are 1200-1600 r / min and 1500-1800 r / min, respectively. When stirring at the same speed, the speed is 1600 r / min. S14. Two different or the same cellulose microspheres were added to a 0.1 mol / L dilute hydrochloric acid solution, stirred and reacted, filtered and dried to obtain porous cellulose microspheres; S15. Two types of porous cellulose microspheres with different or the same particle size are added to an ethylene glycol solution containing PVP. After mixing and stirring evenly, an ethylene glycol solution containing silver nitrate is added dropwise for reaction. The mass-volume ratio of porous cellulose microspheres, PVP, silver nitrate and ethylene glycol is 20-30g:1-2g:3-6g:200-300mL. After the reaction is completed, the mixture is filtered to obtain spiky spherical silver / carbon nanotube / cellulose composite microspheres with different or the same particle size.

2. The TPX / PBT composite release film according to claim 1, characterized in that: The electrospun film has a thickness of 20-30 μm, the TPX film has a thickness of 150-180 μm, and the PBT film has a thickness of 120-150 μm.

3. The method for preparing the TPX / PBT composite release film according to claim 1, characterized in that, The following steps are involved: S1. Two types of spiky silver / carbon nanotube / cellulose composite microspheres with different or the same particle size were added to TPX and PBT respectively. After being mixed evenly, they were added to a twin-screw extruder for granulation to prepare modified TPX particles and PBT particles. S2. Modified TPX particles and PBT particles are cast into films using a single-screw extruder to obtain TPX films and PBT films; S3. Stack the three layers of film in sequence: TPX film, SiC electrospun film and PBT film. Heat the SiC electrospun film and then pressurize it to obtain the TPX / PBT composite release film.

4. The method for preparing the TPX / PBT composite release film according to claim 3, characterized in that: In step S1, the mass ratio of spiky silver / carbon nanotube / cellulose composite microspheres to TPX is 0.2-0.5:10, and the mass ratio of spiky silver / carbon nanotube / cellulose composite microspheres to PBT is 0.2-0.4:

10.

5. The method for preparing the TPX / PBT composite release film according to claim 3, characterized in that: In step S3, the heating temperature of the SiC electrospun film is 220-250℃, and the pressure applied is 4-8 N / cm. 2 .

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