Oiling agent for polytetrafluoroethylene cable wrapping tape, polytetrafluoroethylene cable wrapping tape and preparation method of polytetrafluoroethylene cable wrapping tape

Abstract

The invention relates to an oiling agent for a polytetrafluoroethylene cable wrapping tape, the polytetrafluoroethylene cable wrapping tape and a preparation method of the polytetrafluoroethylene cable wrapping tape. The oil agent is a multi-component oil agent and comprises an oil agent A, an oil agent B and an oil agent C; the oiling agent A is C5-C6 hydrocarbons, and the distillation range is 30-80 DEG C; the oiling agent B is C7-C9 hydrocarbon, and the distillation range is 100-150 DEG C; and the oiling agent C is mainly C10-C12 hydrocarbons, and the distillation range is 160-200 DEG C. The oiling agent for the polytetrafluoroethylene cable wrapping tape provided by the invention contains three oiling agents A, B and C with different boiling ranges, so that a solvent system has a relatively wide boiling range, the oiling agents with different components can be removed in stages in the preparation process of the polytetrafluoroethylene cable wrapping tape, smooth proceeding of subsequent stretching and forming is ensured, and the service life of the polytetrafluoroethylene cable wrapping tape is prolonged. And the obtained polytetrafluoroethylene cable wrapping tape is uniform in molding and easy to sinter, and has very good mechanical properties.

Description

Technical Field

[0001] This invention relates to the field of cable technology, specifically to an oil agent for wrapping polytetrafluoroethylene (PTFE) cables, PTFE cable wrapping tape, and a method for preparing the same. Background Technology

[0002] Polytetrafluoroethylene (PTFE) possesses excellent high-temperature resistance, superior chemical stability (resistance to strong acids, strong alkalis, and organic solvents), and good electrical insulation properties. Therefore, PTFE is a high-performance material widely used in the wire and cable industry, primarily for cable insulation layers.

[0003] Polytetrafluoroethylene (PTFE) dispersion resin exhibits fiber-forming properties; under shear force, PTFE particles can form a mesh structure of a certain strength. When shear force is applied to the resin through extrusion, a certain amount of oil must be added to the resin to reduce resistance and prevent damage to the resin's fibrous structure.

[0004] In practical production, current wrapping tape manufacturing processes primarily involve uniformly dispersing polytetrafluoroethylene (PTFE) particles in a single oiling agent (a processing aid) to form a paste. This paste is then extruded and shaped, with thickness and width achieved through calendering and stretching. Finally, the tape is degreased and sintered. Wrapping tape prepared in this way is prone to unevenness and cracking during sintering, failing to form a dense product and affecting the overall cable's normal use and basic performance.

[0005] Furthermore, since oiling agents significantly affect the dispersibility of PTFE particles and consequently the uniformity of extrusion molding, calendering, and stretching during the molding process, the added oiling agents must be easily mixed with the resin and completely removed from the extrudate without residue during degreasing. Additives with low surface tension facilitate diffusion into PTFE particles, but surface tension increases with boiling point. Low-boiling-point additives tend to evaporate prematurely, preventing the PTFE particles from bonding tightly; high-boiling-point additives have high surface tension, hindering diffusion into the resin. Only by effectively controlling the content of oiling agents during the molding process can the smooth progress of subsequent stretching and molding be ensured, guaranteeing that its performance remains unaffected. Summary of the Invention

[0006] To address the shortcomings and deficiencies of existing technologies, the primary objective of this invention is to provide an oiling agent for polytetrafluoroethylene (PTFE) cable wrapping tape. This oiling agent is a multi-component compound with a wide boiling range. During the preparation of PTFE cable wrapping tape, it can remove different components of the oiling agent in stages, ensuring the smooth progress of subsequent stretching and molding. Furthermore, the resulting PTFE cable wrapping tape is uniformly formed, easy to sinter, and possesses excellent mechanical properties.

[0007] Another object of the present invention is to provide a polytetrafluoroethylene cable wrapping tape.

[0008] This invention also provides a method for preparing the aforementioned polytetrafluoroethylene (PTFE) cable wrapping tape. In preparing the PTFE cable wrapping tape, this invention adds the aforementioned multi-component oiling agent and a non-ionic penetration enhancer to help the oiling agent better penetrate into the PTFE particles for easier dispersion.

[0009] The objective of this invention is achieved through the following technical solution:

[0010] An oiling agent for wrapping polytetrafluoroethylene cables, characterized in that the oiling agent is a multi-component oiling agent, comprising oiling agent A, oiling agent B and oiling agent C; wherein the mass ratio of oiling agent A, oiling agent B and oiling agent C is (2~3):(4~5):(2~3).

[0011] Furthermore, the oil agent A is a C5-C6 hydrocarbon (mainly alkanes and cycloalkanes) with a molecular weight of 72-86 g / mol and a distillation range of 30-80℃.

[0012] Furthermore, the oil agent B is a C7~C9 hydrocarbon (mainly alkanes, cycloalkanes, and a small amount of aromatics), with a molecular weight of 98~128 g / mol and a distillation range of 100~150℃.

[0013] Furthermore, the oil agent C is mainly C 10 ~C 12 Hydrocarbons (including alkanes, cycloalkanes, and aromatics) with a molecular weight of 142-170 g / mol and a distillation range of 160-200℃.

[0014] Furthermore, the mass ratio of oil A: oil B: oil C is (2~3):(4~5):(2~3). For example, in some specific embodiments, the mass ratio of oil A: oil B: oil C can be 2:5:3, 3:5:2, or 3:4:3, etc.

[0015] The present invention also provides a polytetrafluoroethylene cable wrapping tape, the raw materials for which include 335-455 parts by weight of polytetrafluoroethylene, 0.5-2 parts by weight of penetration promoter and 200 parts by weight of multi-component oil agent.

[0016] The method for preparing the polytetrafluoroethylene cable wrapping tape of the present invention includes the following steps:

[0017] S1. Raw material screening and mixing: By weight, 335-455 parts of polytetrafluoroethylene particles are sieved, and then 0.5-2 parts of penetration enhancer and 100 parts of multi-component oil agent are added and mixed.

[0018] S2. Maturation: The mixed raw materials are matured to obtain a raw material;

[0019] S3. Pre-forming: The cured blank is placed into a mold and pre-pressed into a rod-shaped mold blank;

[0020] S4. Pressing and calendering: Add 100 parts of multi-component oil to wet the surface of the rod-shaped die blank, and then calender it into a film;

[0021] S5. Stretching: Stretching the calendered film;

[0022] S6. Degreasing: Degrease the stretched membrane to remove oil and penetration enhancers;

[0023] S7. Sintering: The degreased film is sintered in air atmosphere to obtain the polytetrafluoroethylene cable wrapping tape.

[0024] Further, in step S1, the total amount of the multi-component oiling agent is 100 parts, and the amount of PTFE particles is 335-455 parts. In this step, the mass fraction of the multi-component oiling agent (referring to the fraction of the multi-component oiling agent in the total mass of the multi-component oiling agent and PTFE particles) is 18%-23%. For example, in some specific embodiments, the mass fraction of the multi-component oiling agent can be 18%, 19%, 20%, 21%, 22%, or 23%, etc.

[0025] Further, in step S1, the penetration enhancer is a nonionic penetration enhancer, preferably a small molecule alcohol ether (carbon chain length ≤ 3, molecular weight < 100 g / mol, boiling point below 200℃) or a short / medium chain alkyl glycoside (C6~C4). 10 At least one of the following: (initial thermal decomposition temperature < 240℃).

[0026] In a more preferred embodiment, the penetration enhancer may be at least one of ethylene glycol monomethyl ether, propylene glycol monomethyl ether, and alkyl glycoside APG-0810. The ethylene glycol monomethyl ether has a boiling point of 124°C, the propylene glycol monomethyl ether has a boiling point of 120°C, and the alkyl glycoside APG-0810 has an initial thermal decomposition temperature of 210-220°C.

[0027] Further, in step S1, the mass of the penetration enhancer is 0.5-2% of the mass of the multi-component oil agent. In some specific embodiments, the mass of the penetration enhancer is 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, 1.6%, 1.7%, 1.8%, 1.9%, 2%, etc., of the multi-component oil agent.

[0028] Furthermore, in step S1, the sieving is performed using a 5-20 mesh sieve.

[0029] Further, in step S1, the mixing involves first adding a penetration enhancer to the sieved polytetrafluoroethylene particles, and then adding a multi-component oiling agent.

[0030] Further, in step S1, the mixing is carried out at a temperature of 10~20℃ using a three-dimensional mixing tank, the mixing time for adding the penetration enhancer is 5~10 minutes, and the mixing time for adding the multi-component oil agent is 10~15 minutes.

[0031] More preferably, in step S1, the mixing temperature is 15~18°C.

[0032] Furthermore, in step S2, the ripening temperature is 40~95℃ and the time is 4~16h.

[0033] Furthermore, the ripening temperature is more preferably 70~85°C, and the ripening time is more preferably 10~12h.

[0034] Further, in step S3, the preforming involves placing the cured polytetrafluoroethylene granules into a mold for pre-pressing to form a rod-shaped mold blank; the pre-pressing pressure is 2~6 MPa, and the pre-pressing temperature is 20~30℃.

[0035] Furthermore, the pre-compression pressure is more preferably 3~4 MPa, and the pre-compression temperature is more preferably 25~28°C.

[0036] Further, in step S4, the rod-shaped film preform is impregnated with a multi-component oil before calendering, and then calendered into a sheet-like long strip of 0.04mm~0.70mm by rollers at a temperature of 80~100℃. All oil A is removed during the calendering process.

[0037] Furthermore, the roller temperature is preferably 85~95℃ and the diaphragm thickness is 0.05mm.

[0038] Furthermore, in step S5, the stretching temperature is 150~170℃, and the stretching ratio is 1~8 times. During the stretching process, all oil A and oil B are removed, leaving a portion of oil C to assist in stretching the polytetrafluoroethylene sheet and strip more uniformly.

[0039] Furthermore, the stretching temperature is more preferably 155~160℃, and the stretching ratio is more preferably 1.5~2 times.

[0040] Furthermore, in step S6, the degreasing temperature is 240~280℃, and the degreasing time is 30~120 minutes. During the degreasing process, all oils and penetration enhancers are removed to prevent them from affecting the performance of the wrapping tape.

[0041] Furthermore, the degreasing temperature is more preferably 250~260℃, and the degreasing time is more preferably 40~60min.

[0042] Furthermore, in step S7, the sintering temperature is 300~600℃, and the sintering time is 1~30min.

[0043] Furthermore, the sintering temperature is more preferably 500~550℃, and the sintering time is more preferably 1~2min.

[0044] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0045] (1) The oil agent for polytetrafluoroethylene cable wrapping tape provided by the present invention contains three oil agents A, B and C with different boiling ranges, so that the solvent system has a wide boiling range. During the preparation of polytetrafluoroethylene cable wrapping tape, the oil agents of different components can be removed in stages to ensure the smooth progress of subsequent stretching and molding. The resulting polytetrafluoroethylene cable wrapping tape is uniformly shaped, easy to sinter, and has good mechanical properties.

[0046] (2) The polytetrafluoroethylene cable wrapping tape of the present invention also incorporates a non-ionic penetration enhancer during the preparation process to help the oil penetrate the polytetrafluoroethylene particles more effectively. The present invention removes the oil and penetration enhancer in stages during the molding process, controlling the oil content and thus ensuring more uniform dispersion of the polytetrafluoroethylene resin particles, laying the foundation for subsequent sintering and wrapping processes.

[0047] (3) In the preparation process of the polytetrafluoroethylene cable wrapping tape described in this invention, the paste extrusion molding method, by adding a penetration enhancer and changing the mass fraction and type of oil, can achieve the control of the network structure and mechanical properties of the membrane. This invention provides a new approach for preparing uniform, easily moldable, and easily sintered PTFE cable wrapping tape, and has good application prospects. Attached Figure Description

[0048] Figure 1 The images show the microstructure of polytetrafluoroethylene cable wrapping tapes prepared in Examples 1, 4, 5 and Comparative Example 1 of the present invention, where (a) is Example 1, (b) is Example 4, (c) is Example 5 and (d) is Comparative Example 1.

[0049] Figure 2 The mechanical properties of the polytetrafluoroethylene cable wrapping tapes prepared in Examples 1, 4, 5 and Comparative Example 1 of this invention are shown in the diagram. Detailed Implementation

[0050] The present invention will be further described in detail below with reference to embodiments and accompanying drawings, but the embodiments of the present invention are not limited thereto. All raw materials involved in the present invention can be purchased directly from the market. For process parameters not specifically specified, conventional techniques can be referred to.

[0051] Example 1

[0052] The polytetrafluoroethylene (PTFE) dispersion resin used in this embodiment is brand F201, supplied by Daikin Fluorochemicals (China) Co., Ltd., with a bulk density of 0.45 g / cm³. 3 The average particle size is 500 μm.

[0053] In this embodiment, the multi-component oil agent used, oil agent A is: petroleum ether from Jiyesheng Chemical Co., Ltd., product number 2029 (C). 5-6 Alkane, molecular weight approximately 72-86 g / mol); Oil B is: ExxonMobil's isoparaffin solvent Isopar E (isoparaffin C 8-9 The three oils are: Alkane (molecular weight approximately 114–128 g / mol); Oil C is ExxonMobil's isoalkane solvent Isopar G (primarily isodecane, molecular weight approximately 142–156 g / mol). The physical properties (including distillation range, density, and viscosity) of the three oils are shown in Table 1.

[0054] The penetration enhancer used in this embodiment is propylene glycol methyl ether provided by Jiangsu Yida Chemical Co., Ltd., with a molecular weight of 90.12 and a boiling range of 117~125℃.

[0055] Table 1

[0056]

[0057] In this embodiment, the formulation of the multi-component oil is as follows: the mass ratio of 2029 (oil agent A), Isopar E (oil agent B) and Isopar G (oil agent C) is 2:5:3.

[0058] Prepare polytetrafluoroethylene cable wrapping tape according to the following steps:

[0059] S1: Use a 20-mesh sieve to remove any agglomerated PTFE dispersion particles. According to the formula, mix the sieved PTFE dispersion resin powder and the penetration enhancer in a three-dimensional mixer at 30 r / min for 5 min. Then add the multi-component oil and mix for 15 min. The mixing process is carried out at 18℃. In this step, the mass fraction of the multi-component oil (referring to the percentage of the multi-component oil in the total mass of the multi-component oil and PTFE particles) is 20%; the mass of the penetration enhancer is 1% of the total mass of the multi-component oil. By weight, there are 400 parts PTFE particles, 100 parts multi-component oil, and 1 part penetration enhancer.

[0060] S2: The mixed raw materials are left to stand and mature in an oven at 80°C for 12 hours. Part of the oil agent A evaporates, making the polytetrafluoroethylene particles fluffy. The oil agent can fully penetrate into the PTFE dispersion resin particles, thereby uniformly dispersing and forming a PTFE paste.

[0061] S3: Press the matured PTFE paste at 4MPa for 5 minutes to form a uniform blank.

[0062] S4: Prepare 100 parts of multi-component oil according to the ratio of this embodiment (oil A: oil B: oil C = 2:5:3), impregnate the blank with the multi-component oil, and calender it at 85°C using a twin-roll calender to form a film with a thickness of about 500μm. At this time, oil A is completely removed.

[0063] S5: The calendered film is stretched again by 1.5 times by rollers at 160°C. At this time, oil A and oil B are completely removed, leaving some oil C to assist in stretching, making the film more uniform during the stretching process.

[0064] S6: Dry the stretched membrane in an oven at 240°C for 12 hours to completely remove liquid oil and penetration enhancer from the membrane.

[0065] S7: Sinter the strip treated in S6 at 500℃ for 1 minute to obtain the PTFE cable wrapping tape.

[0066] Example 2

[0067] The difference between this embodiment and Example 1 is that the polytetrafluoroethylene (PTFE) dispersion resin is replaced with Teflon 605XTX, supplied by Chemours Chemicals (Shanghai) Co., Ltd., with a bulk density of 0.5 g / cm³. 3 The average particle size is 675 μm; other process parameters remain unchanged.

[0068] Example 3

[0069] The difference between this embodiment and Embodiment 1 is that the multi-component oil agent is prepared according to the ratio of 2029 (oil agent A): Isopar E (oil agent B): Isopar G (oil agent C) = 3:4:3, while the other process parameters remain unchanged.

[0070] Example 4

[0071] The difference between this embodiment and Embodiment 1 is that the multi-component oil agent is prepared according to the ratio of 2029 (oil agent A): Isopar E (oil agent B): Isopar G (oil agent C) = 3:5:2, while the other process parameters remain unchanged.

[0072] Example 5

[0073] The difference between this embodiment and Embodiment 1 is that in step S1, the mass fraction of the multi-component oil agent is 23% (i.e., the components in step S1 are: 100 parts of multi-component oil agent, 335 parts of PTFE, and 1 part of penetration enhancer); the other process parameters remain unchanged.

[0074] Example 6

[0075] The difference between this embodiment and Embodiment 1 is that the penetration enhancer is APG0810 provided by Guangzhou Zhonghai Chemical Co., Ltd., with an initial thermal decomposition temperature of approximately 210-220℃; the other process parameters remain unchanged.

[0076] Example 7

[0077] The polytetrafluoroethylene (PTFE) dispersion resin used in this embodiment is brand F201, supplied by Daikin Fluorochemicals (China) Co., Ltd., with a bulk density of 0.45 g / cm³. 3 The average particle size is 500 μm.

[0078] In this embodiment, the multi-component oil agent used, oil agent A is: petroleum ether from Jiyesheng Chemical Co., Ltd., product number 2029 (C). 5-6 Alkane, molecular weight approximately 72-86 g / mol); Oil B is: Total Energy Group alkane solvent Solane 100-140 (isomeric C) 7-9 The three oils are: Alkane (molecular weight approximately 100-128 g / mol); Oil C is: Idemitsu Kogyo's IP CleanLX isoalkanes (mainly isododecane, molecular weight approximately 142-170 g / mol). The physical properties (including distillation range, density, and viscosity) of the three oils are shown in Table 2.

[0079] The penetration enhancer used in this embodiment is propylene glycol methyl ether provided by Jiangsu Yida Chemical Co., Ltd., with a molecular weight of 90.12 and a boiling range of 117~125℃.

[0080] Table 2

[0081]

[0082] In this embodiment, the multi-component oil formulation is as follows: the mass ratio of 2029 (oil A), Solane 100-140 (oil B), and IPClean LX (oil C) is 2:5:3. In step S1, the mass fraction of the multi-component oil is 20%, and the mass of the penetration enhancer accounts for 1% of the total mass of the oil (i.e., in step S1, each component is: 100 parts of multi-component oil, 400 parts of PTFE, and 1 part of penetration enhancer).

[0083] Polytetrafluoroethylene cable wrapping tape was prepared according to the preparation method described in Example 1.

[0084] Example 8

[0085] The difference between this embodiment and Example 7 is that the polytetrafluoroethylene (PTFE) dispersion resin is replaced with Teflon 605XTX, supplied by Chemours Chemicals (Shanghai) Co., Ltd., with a bulk density of 0.5 g / cm³. 3 The average particle size is 675 μm; other process parameters remain unchanged.

[0086] Example 9

[0087] The difference between this embodiment and embodiment 7 is that the multi-component oil is prepared according to the ratio of 2029 (oil A): Solane 100-140 (oil B): IP Clean LX (oil C) = 3:4:3 (mass ratio), while the other process parameters remain unchanged.

[0088] Example 10

[0089] The difference between this embodiment and embodiment 7 is that the multi-component oil is prepared according to the ratio of 2029 (oil A): Solane 100-140 (oil B): IP Clean LX (oil C) = 3:5:2 (mass ratio), while the other process parameters remain unchanged.

[0090] Example 11

[0091] The difference between this embodiment and Embodiment 7 is that the mass fraction of the multi-component oil agent is 23% (i.e., the components in step S1 are 100 parts of multi-component oil agent, 335 parts of PTFE, and 1 part of penetration enhancer); the other process parameters remain unchanged.

[0092] Example 12

[0093] The difference between this embodiment and embodiment 7 is that the penetration enhancer is APG0810 provided by Guangzhou Zhonghai Chemical Co., Ltd., with an initial thermal decomposition temperature of approximately 210~220℃; the other process parameters remain unchanged.

[0094] Comparative Example 1

[0095] This comparative example prepares polytetrafluoroethylene cable wrapping tape according to the method described in Example 1, but differs from Example 1 in that:

[0096] The polytetrafluoroethylene (PTFE) dispersion resin used in this comparative example, brand name F201, was supplied by Daikin Fluorochemicals (China) Co., Ltd., and its bulk density was 0.45 g / cm³. 3 The average particle size is 500 μm.

[0097] In this comparative example, only one oiling agent, IP Clean LX (isododecane), was used in steps S1 and S4. In step S1, the mass fraction of the oiling agent was 20% (400 parts PTFE particles and 100 parts multi-component oiling agent), and no penetration enhancer was added.

[0098] Comparative Example 2

[0099] This comparative example prepares polytetrafluoroethylene cable wrapping tape according to the method described in Example 1, but differs from Example 1 in that:

[0100] The formulation of the multi-component oil used in this comparative example is 2029 (oil A): Solane 100-140 (oil B): IPClean LX (oil C) = 4:2:4 (mass ratio).

[0101] The penetration enhancer added in this comparative example is propylene glycol methyl ether provided by Jiangsu Yida Chemical Co., Ltd., with a boiling range of 117~125℃.

[0102] Comparative Example 3

[0103] This comparative example prepares polytetrafluoroethylene cable wrapping tape according to the method described in Example 1, but differs from Example 1 in that:

[0104] The multi-component oil formulation used in this comparative example is 2029 (oil A): Solane 100-140 (oil B): IPClean LX (oil C) = 2:5:3 (mass ratio). The mass fraction of the oil in step S1 is 20%.

[0105] The penetration enhancer added in this comparative example is propylene glycol methyl ether provided by Jiangsu Yida Chemical Co., Ltd., with a boiling range of 117~125℃. The mass of the penetration enhancer accounts for 5% of the total mass of the multi-component oil agent in step S1.

[0106] Performance test results:

[0107] The microstructures of the polytetrafluoroethylene cable wrapping tapes prepared in Examples 1, 4, 5 and Comparative Example 1 of this invention are as follows: Figure 1 As shown.

[0108] The mechanical properties of the polytetrafluoroethylene cable wrapping tapes prepared in Examples 1, 4, 5 and Comparative Example 1 of this invention are as follows: Figure 2 As shown.

[0109] The mechanical properties of the polytetrafluoroethylene cable wrapping tapes prepared in Examples 1, 2, 3, 4, 5, 7, 9, 10 and Comparative Examples 1, 2, 3 of the present invention are shown in Table 3.

[0110] Figure 1The microstructures of PTFE cable wrapping tapes prepared with different proportions of multi-component oil agents and PTFE cable wrapping tapes prepared with a single oil agent are shown. The microstructure of the PTFE cable wrapping tapes can be divided into three parts: an island-like structure formed by the aggregation of PTFE particles, a fibrous structure obtained by stretching PTFE particles, and a microporous structure between microfibers. It can be observed that the PTFE cable wrapping tape prepared in Comparative Example 1 has a more obvious PTFE particle island structure with a single-component oil agent. Figure 1 The presence of fewer micropores (d) indicates that the PTFE particles and oil were not mixed evenly during the mixing process, resulting in insufficient oil absorption. Furthermore, the oil content was not controlled during subsequent molding, thus preventing the PTFE particles from being fully stretched during calendering and stretching.

[0111] The polytetrafluoroethylene cable wrapping tape prepared in Example 1 ( Figure 1 (a) exhibits the best morphological structure, forming an oriented, fluffy, porous structure. This indicates that the PTFE particles are uniformly dispersed during the preparation process, and the particles are subjected to uniform stress during calendering and stretching, resulting in a uniform and oriented microporous structure. This demonstrates that the addition of the penetration enhancer and multi-component oiling agent allows the oiling agent to better penetrate the PTFE particles, thereby ensuring the uniformity of subsequent molding. In Example 4 ( Figure 1 In example (b), by changing the proportion of the multi-component oil agent, the proportion of oil agent A was increased and the proportion of oil agent C was decreased. Some island structures were observed, which may be due to uneven particle dispersion caused by the low oil content during the stretching process. Example 5 ( Figure 1 (c) In the case of altering the mass fraction of the multi-component oil, it was observed that the microporous structure was excessively stretched, which was caused by excessive oil content.

[0112] Figure 2 The stress-strain curves verified the conclusions observed in the electron microscope images. The yield point tensile stress of the PTFE cable wrapping tape with an oriented porous structure reached 17.64 ± 0.52 MPa, and the initial modulus reached 92.48 ± 4.45 MPa. Meanwhile, the mechanical properties of other embodiments and comparative examples are shown in Table 3.

[0113] Mechanical property testing method: The yield point tensile stress and strain of the polytetrafluoroethylene (PTFE) cable wrapping tape were tested using a Shimadzu AGS-X electronic universal testing machine. The tensile rate used for measurement was 100 mm / min, and the tensile temperature was room temperature. All data were taken as the average of 5 measurements.

[0114] Table 3 Mechanical properties of PTFE wrapping tape

[0115]

[0116] As can be seen from the data in Table 3, compared with Examples 1-12 of the present invention, when the proportion of only one or three oil agents added is not within the preferred range described in the present invention, the mechanical properties of the polytetrafluoroethylene cable wrapping tape prepared in Comparative Examples 1 and 2 are significantly reduced; when the amount of penetration enhancer added exceeds the preferred range described in the present invention, the mechanical properties of the polytetrafluoroethylene cable wrapping tape prepared in Comparative Example 3 also deteriorate significantly.

[0117] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. An oiling agent for wrapping polytetrafluoroethylene (PTFE) cables, characterized in that, The oil is a multi-component oil, including oil A, oil B and oil C; the mass ratio of oil A, oil B and oil C is (2~3):(4~5):(2~3); Wherein, oil agent A is a C5-C6 hydrocarbon with a molecular weight of 72-86 g / mol and a distillation range of 30-80℃; oil agent B is a C7-C9 hydrocarbon with a molecular weight of 98-128 g / mol and a distillation range of 100-150℃; and oil agent C is mainly C5 hydrocarbon. 10 ~C 12 Hydrocarbons with a molecular weight of 142-170 g / mol and a distillation range of 160-200℃.

2. The oiling agent for wrapping polytetrafluoroethylene cables according to claim 1, characterized in that, The mass ratio of oil A, oil B and oil C is 2:5:3, 3:5:2 or 3:4:

3.

3. A polytetrafluoroethylene (PTFE) cable wrapping tape, characterized in that, The raw materials for its preparation include 335-455 parts by weight of polytetrafluoroethylene, 0.5-2 parts by weight of penetration enhancer and 200 parts by weight of the multi-component oil agent as described in claim 1 or 2.

4. The method for preparing the polytetrafluoroethylene cable wrapping tape according to claim 3, characterized in that, Includes the following steps: S1: By weight, 335-455 parts of polytetrafluoroethylene particles are sieved, and then 0.5-2 parts of penetration enhancer and 100 parts of the multi-component oil agent as described in claim 1 or 2 are added and mixed. S2: The mixed raw materials are matured to obtain the embryo material; S3: Place the cured blank into a mold and pre-press it into a rod-shaped mold blank; S4: Add 100 parts by weight of the multi-component oil agent as described in claim 1 or 2, impregnate the surface of the rod-shaped die blank, and then calender it into a film; S5: Stretch the calendered film; S6: Degrease the stretched membrane to remove oil and penetration enhancer; S7: The degreased membrane is sintered in air to obtain the polytetrafluoroethylene cable wrapping tape.

5. The method for preparing polytetrafluoroethylene cable wrapping tape according to claim 4, characterized in that, In step S1, the penetration enhancer is a nonionic penetration enhancer; specifically, it includes small molecule alcohol ethers with a carbon chain length ≤3, molecular weight <100 g / mol, and boiling point below 200℃, or C6~C 10 At least one of the following: short / medium chain alkyl glycosides with an initial thermal decomposition temperature below 240 °C.

6. The method for preparing polytetrafluoroethylene cable wrapping tape according to claim 5, characterized in that, The penetration enhancer is at least one of ethylene glycol monomethyl ether, propylene glycol monomethyl ether, and alkyl glycoside APG-0810.

7. The method for preparing polytetrafluoroethylene cable wrapping tape according to claim 4, characterized in that, In step S1, the sieving is performed using a 5-20 mesh sieve; The mixing process involves first adding a penetration enhancer to the sieved polytetrafluoroethylene particles, followed by adding a multi-component oiling agent. The mixing temperature is 10~20℃, and the mixing is carried out in a three-dimensional mixing tank. The mixing time for adding the penetration enhancer is 5~10 minutes, and the mixing time for adding the multi-component oil agent is 10~15 minutes.

8. In the method for preparing polytetrafluoroethylene cable wrapping tape according to claim 4, in step S2, the curing temperature is 40~95℃ and the time is 4~16h; In step S3, the pre-compression pressure is 2~6 MPa and the pre-compression temperature is 20~30℃.

9. The method for preparing polytetrafluoroethylene cable wrapping tape according to claim 4, characterized in that, In step S4, the rod-shaped film preform is impregnated with a multi-component oiling agent and then rolled into a sheet-like long strip of 0.04mm~0.70mm by rollers, with the roller temperature being 80~100℃; In step S5, the stretching temperature is 150~170℃, and the stretching ratio is 1~8 times.

10. The method for preparing polytetrafluoroethylene cable wrapping tape according to claim 4, characterized in that, In step S6, the degreasing temperature is 240~280℃, and the degreasing time is 30~120min; In step S7, the sintering temperature is 300~600℃ and the sintering time is 1~30min.

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