High-performance flat base paper as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of insulating electrical materials, and particularly relates to high-performance flat base paper as well as a preparation method and application thereof. According to the preparation method of the high-performance flat base paper provided by the invention, after pulp such as softwood pulp is pulped to 35-45 DEG SR and wet paper sheets are formed, the wet paper sheets are subjected to specific hot-pressing shaping (9.0-11.0 MPa, 9.0-11.0 MPa, 9.0-11.0 MPa, 9.0-11.0 MPa, according to the invention, under the process conditions of temperature of 90-110 DEG C and drying (80-100 DEG C), the organic combination of three core technologies of fiber form regulation, hot-pressing densification and drying optimization is realized, the comprehensive properties such as electrical strength, mechanical property and impregnation property of the flat base paper are effectively improved, and the flat base paper is especially suitable for the field of high-end electrical equipment with strict requirements on the comprehensive properties of insulating materials; the technical problem that the comprehensive performance of flat base paper prepared through an existing technology is low is solved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of insulating electrical materials, and particularly relates to a high-performance flat base paper and a preparation method and application thereof. BACKGROUND

[0002] Electrical insulating paper is a key material for realizing electrical insulation in electrical equipment, and has good dielectric properties, heat resistance and mechanical strength. According to the source of raw materials, it can be divided into plant fiber insulating paper, synthetic fiber insulating paper and composite insulating paper.

[0003] The dry-type bushing of 110kV~500kV voltage grade is in a high-voltage and strong electric field working environment, and also needs to withstand strong wind, rainstorm, sand and other harsh natural environments. The performance of the core insulating material, electrical corrugated paper, is required to be strict: electrically, it needs to have an electrical strength of ≥17kV / mm (resisting long-term high-voltage breakdown), mechanically, it needs to have a transverse tear strength of ≥260mN (resisting strong stress and cold and hot cycle), and impregnation needs to realize uniform resin penetration (SEM score ≥4 / 5, reducing solidification stress concentration); and the performance of the flat base paper as the core raw material of the electrical corrugated paper directly determines the quality of the final product.

[0004] The preparation process of the flat base paper mainly includes beating the pulp slurry prepared by using a PFI beater to form a pulp slurry, forming by a paper machine, hot pressing by a flat hot press and drying; the beating degree of the pulp slurry affects the fiber morphology, when the beating degree is <30°SR, the fiber is not enough to be separated, the interweaving is loose and the porosity is high (42%), and the electrical strength is only 14.8kV / mm, while when the beating degree is >50°SR, the fiber is excessively cut (length <1.0mm), the pore distribution is uneven and the transverse tear strength decreases by 18%, which cannot balance the fiber interweaving density and fiber integrity; when hot pressing, when a low pressure of 5~8MPa is used, the base paper tightness is insufficient (breaking strength 400~450kPa), and when a high pressure of >12MPa is used, the fiber structure is crushed, the local carbonization risk increases, the electrical strength fluctuates ±0.7kV / mm, and the density and fiber protection cannot be balanced; and the beating degree of the pulp slurry, hot pressing and drying process need to be matched, the beating degree needs to be matched with the corresponding hot pressing and drying temperature to adapt to the fiber morphology, for example, long fibers (25°SR) matched with high pressure will cause fiber damage, and short fibers (55°SR) matched with high drying temperature will cause embrittlement, and finally the situation of electrical strength and mechanical difference, impregnation optimization and electrical instability is caused.

[0005] Therefore, in the preparation process of the preparation process of the flat base paper, the process parameters of the beating degree, hot pressing and drying need to be organically combined to realize the improvement of the comprehensive performance of electricity, machinery, impregnation and the like, and meet the insulation demand of the dry bushing and the like electrical equipment. However, the current preparation process of the flat base paper isolates the process parameters of the beating degree, hot pressing and drying, focuses on the improvement of a single aspect, and has low comprehensive performance, which is difficult to meet the insulation demand of the dry bushing and the like electrical equipment. SUMMARY

[0006] Therefore, the present application provides a high-performance flat base paper and a preparation method and application thereof, which are used to solve the technical problem of low comprehensive performance of the flat base paper prepared by the existing process.

[0007] The first aspect of the present application provides a preparation method of a high-performance flat base paper, comprising the following steps:

[0008] The step of beating: soaking the raw pulp board into water to form a pulp slurry and beating the pulp slurry by using a PFI beater to obtain a pulp slurry with a beating degree of 35-45°SR;

[0009] The step of papermaking and forming: using a papermaking machine to make and form the pulp slurry with a beating degree of 35-45°SR to obtain a wet paper sheet;

[0010] The step of hot pressing and forming: using a flat hot press to hot press the wet paper sheet under a hot pressing process of 9.0-11.0 MPa and 90-110°C to obtain a hot-pressed paper;

[0011] The step of drying: drying the hot-pressed paper at a temperature of 80-100°C to a moisture content of ≤5wt% to obtain a high-performance flat base paper.

[0012] Preferably, in the step of beating, the raw pulp board is selected from unbleached coniferous pulp raw pulp boards, and the fiber length is 1.8-2.2 mm and the fiber width is 20-25μm.

[0013] Preferably, in the step of beating, the process of beating the pulp slurry by using the PFI beater comprises: defibrating the pulp slurry with a concentration of 2-8wt% by using the PFI beater for 2-8min, and then beating under a rotation speed of 2000-4000rpm and a gap of 0.1-0.3mm to obtain a pulp slurry with a beating degree of 35-45°SR.

[0014] Preferably, in the step of papermaking and forming, the process of making and forming the pulp slurry by using the papermaking machine comprises: adjusting the concentration of the pulp slurry with a beating degree of 35-45°SR to 0.2wt% by adding water, adjusting the amount of pulp slurry to make the basis weight of the wet paper sheet 60±2g / m 2 , and injecting the wet paper sheet into the forming wire of the papermaking machine, and dehydrating to 75-80% to obtain a wet paper sheet.

[0015] Preferably, in the hot-pressing step, the process of hot-pressing the wet paper sheet includes: hot-pressing the wet paper sheet for 5-15 min to obtain a hot-pressed paper with a basis weight of 60±1 g / m 2 .

[0016] Preferably, in the drying step, the drying device used is a circulating hot air drying oven.

[0017] The second aspect of the present application provides a high-performance flat base paper prepared by the preparation method of the first aspect.

[0018] The third aspect of the present application provides an application of the high-performance flat base paper of the second aspect in the field of electrical equipment insulation.

[0019] The fourth aspect of the present application provides an electrical corrugated paper, and raw materials of the electrical corrugated paper include the high-performance flat base paper of the second aspect.

[0020] The fifth aspect of the present application provides an application of the electrical corrugated paper of the fourth aspect as an insulation material in an electrical environment with a voltage level of 110 kV-500 kV. BRIEF DESCRIPTION OF DRAWINGS

[0021] In order to more clearly illustrate the technical solutions of the specific embodiments or prior art in the present application, the drawings needed to be used in the description of the specific embodiments or prior art will be briefly introduced below. Obviously, the drawings in the following description are some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor on the basis of these drawings.

[0022] Figure 1 The influence of different beating degrees on the average fiber length, porosity and free rate of the flat base paper prepared by the preparation method of the flat base paper provided for Example 1 and Comparative Examples 1-2 of the present application is shown in the result graph.

[0023] Figure 2 The influence of different beating degrees on the mechanical properties of the flat base paper prepared by the preparation method of the flat base paper provided for Example 1 and Comparative Examples 1-2 of the present application is shown in the result graph. DETAILED DESCRIPTION

[0024] The present application provides a high-performance flat base paper and a preparation method and application thereof, which are used to solve the technical problem of low comprehensive performance of the flat base paper prepared by the existing process.

[0025] The technical solutions of the present application will be clearly and completely described below with reference to the drawings. Obviously, the described embodiments are some of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of the present application.

[0026] Embodiment 1

[0027] The embodiment provides a preparation method of high-performance flat base paper, which comprises the following steps: a step of raw material selection and pretreatment, a step of beating by using a PFI beater, a step of wet paper sheet forming by using a paper machine, a step of hot-pressing forming by using a flat hot press, and a step of drying by using a circulating hot air drying oven.

[0028] The step of raw material selection and pretreatment comprises the following steps:

[0029] The unbleached coniferous wood pulp stock board is cut into a size of 10 cm*10 cm, and then is soaked in deionized water with a water temperature of 25±2°C for 12 hours to make the fibers fully swell, so as to prepare a pulp liquid with a concentration of 5wt%; wherein the fiber length of the unbleached coniferous wood pulp is between 1.8-2.2 mm, the fiber width is between 20-25 μm, the ash content is 0.57%, and the moisture content is 4.09%.

[0030] The step of beating by using a PFI beater comprises the following steps:

[0031] The PFI beater (model: PFI Mill-3000) is adjusted to a rotating speed of 3000 rpm, a beating gap of 0.2 mm, and a target beating degree of 40°SR, the pulp liquid is put into the PFI beater, a defibration program (5 min) is started to disperse the fiber bundles, and then beating is performed, and the beating degree (measured by a Schopper-Riegler instrument) is monitored in real time to ensure that the beating degree of the pulp liquid after final beating is 40±2°SR.

[0032] The step of wet paper sheet forming by using a paper machine comprises the following steps:

[0033] The pulp liquid after beating is added with water, the concentration is adjusted to 0.2wt%, and the mixture is stirred at 500 rpm for 10 min, the amount of the pulp liquid is adjusted to make the basis weight of the wet paper sheet 60±2 g / m 2 , the wet paper sheet is obtained by dehydrating the forming wire of the paper machine, and the water content of the wet paper sheet is between 75%-80%.

[0034] The step of hot-pressing forming by using a flat hot press comprises the following steps:

[0035] The wet paper sheet is hot-pressed into a shape using a flat hot press (model: HP-50T, copper mesh and copper plate combined mold), the hot-pressing pressure is 10.0 MPa, the hot-pressing temperature is 100±2℃, the time is 10 min, and the pressing is stopped until the basis weight is stable at 60±1 g / m², to obtain hot-pressed paper;

[0036] The step of drying using a circulating hot air drying oven includes:

[0037] The hot-pressed paper is dried in a circulating hot air drying oven (model: DHG-9070), the drying temperature is 90±2℃, and the drying is stopped until the target moisture content is ≤5wt% (real-time monitoring is performed using a halogen moisture meter), to obtain high-performance flat base paper.

[0038] Comparative Example 1

[0039] The present comparative example provides a preparation method of flat base paper, which is different from Example 1 in that the step of beating using a PFI beater is used.

[0040] The step of beating using a PFI beater in the present comparative example includes: adjusting the parameters of the PFI beater (model: PFI Mill-3000) to a rotation speed of 3000 rpm and a beating gap of 0.2 mm, setting the target beating degree to 25°SR, feeding the slurry into the PFI beater, starting the defibration program (5 min) to disperse the fiber bundles, and then beating, and real-time monitoring of the beating degree (measured by a Schopper-Riegler instrument) to ensure that the beating degree of the slurry after the final beating is completed is 25±2°SR.

[0041] Comparative Example 2

[0042] The present comparative example provides a preparation method of flat base paper, which is different from Example 1 in that the step of beating using a PFI beater is used.

[0043] In the present comparative example, the step of beating using a PFI beater includes: adjusting the parameters of the PFI beater (model: PFI Mill-3000) to a rotation speed of 3000 rpm and a beating gap of 0.2 mm, setting the target beating degree to 55°SR, feeding the slurry into the PFI beater, starting the defibration program (5 min) to disperse the fiber bundles, and then beating, and real-time monitoring of the beating degree (measured by a Schopper-Riegler instrument) to ensure that the beating degree of the slurry after the final beating is completed is 55±2°SR.

[0044] Example 2

[0045] Referring to Table 3, the present example provides a set of orthogonal test preparation methods of flat base paper, which is different from Example 1 in that the step of hot-pressing into a shape using a flat hot press and the step of drying using a circulating hot air drying oven are used.

[0046] In this embodiment, the step of hot-pressing molding using a flat hot press comprises: hot-pressing molding the wet paper sheet using a flat hot press (model: HP-50T, copper mesh and copper plate combined mold), the hot-pressing pressure is 5 MPa, 10.0 MPa, and 15 MPa respectively, the hot-pressing temperature is 80℃, 100℃, and 120℃ respectively, the time is 10 min, and the pressing is stopped until the basis weight is stable at 60±1 g / m², to obtain the hot-pressed paper.

[0047] In this embodiment, the step of drying using a circulating hot air drying oven comprises: drying the hot-pressed paper in a circulating hot air drying oven (model: DHG-9070), the drying temperature is 70℃, 90℃, and 110℃ respectively, and the drying is stopped until the target moisture content is ≤5wt% (real-time monitoring is performed using a halogen moisture meter).

[0048] Table 3: Process parameters of a set of orthogonal test preparation methods of flat base paper provided by Example 2

[0049]

[0050] Example 3

[0051] Referring to Table 4, this embodiment provides a set of orthogonal test preparation methods of flat base paper, and the difference between this set of preparation methods and Example 1 is that the step of hot-pressing molding using a flat hot press and the step of drying using a circulating hot air drying oven.

[0052] In this embodiment, the step of hot-pressing molding using a flat hot press comprises: hot-pressing molding the wet paper sheet using a flat hot press (model: HP-50T, copper mesh and copper plate combined mold), the hot-pressing pressure is 5 MPa, 10.0 MPa, and 15 MPa respectively, the hot-pressing temperature is 80℃, 100℃, and 120℃ respectively, the time is 10 min, and the pressing is stopped until the basis weight is stable at 60±1 g / m², to obtain the hot-pressed paper.

[0053] In this embodiment, the step of drying using a circulating hot air drying oven comprises: drying the hot-pressed paper in a circulating hot air drying oven (model: DHG-9070), the drying temperature is 70℃, 90℃, and 110℃ respectively, and the drying is stopped until the target moisture content is ≤5wt% (real-time monitoring is performed using a halogen moisture meter).

[0054] Experimental Example 1

[0055] This experimental example 1 tests the performance of the flat base paper provided by Example 1, Comparative Examples 1-2, and Example 2-3.

[0056] Among them, the process of performance testing includes:

[0057] For Example 1, tests were conducted on the pulp and sheet paper with different degrees of freeness provided in Comparative Examples 1-2. The tests included: measuring the average fiber length in the pulp; measuring the porosity and free fiber content of the sheet paper; conducting breakdown strength tests according to GB / T1408.1-2016 standard, with a sample size of 100mm × 100mm and a DC voltage boost rate of 200 V / s; testing the longitudinal tensile strength according to GB / T 12914-2018 standard; testing the transverse tear strength according to GB / T 455-2002 standard, and calculating the anisotropy index (transverse / longitudinal tensile strength ratio); impregnating the sheet paper in epoxy resin (viscosity 200 mPa·s, 25℃) for 30 min to study the effect of freeness on epoxy resin impregnation, and observing the resin distribution through SEM cross-sections, including resin distribution uniformity (SEM score). The cross-section of the impregnated base paper was observed using a scanning electron microscope at a magnification of 2000×. The following criteria were used for scoring:

[0058] 5 points: The resin uniformly fills the micropores (pore size ≤ 2μm), and there are no voids at the interface;

[0059] 4 points: The resin was slightly enriched in local pores (pore size 2–5 μm), but no continuous layer was formed;

[0060] 3 points: The resin accumulates in large pores (pore size > 5μm), and there are void regions;

[0061] 2 points: The resin is distributed in patches;

[0062] 1 point: The resin only adheres to the surface and does not penetrate the interior.

[0063] The scoring was completed independently by two technicians, and the results were averaged as integers.

[0064] The performance test results are as follows Figures 1-2 As shown in Table 1-2; from Figure 1 The test results show that at low freeness (25±2°SR), the fibers are relatively long (2.1 mm), the porosity is moderate (42%), but the fibers are loosely interwoven and the free rate is low (500 mL). At medium freeness (40±2°SR), the fibers are fully bristled, the porosity drops to 40%, and the free rate increases to 700 mL, forming a dense and uniform structure. At high freeness (55±2°SR), the fibers are excessively cut, the porosity increases but is unevenly distributed. Table 1 shows that at 40±2°SR, the electrical strength is the highest (17.2 kV / mm), the fibers are tightly interwoven, and the pores are closed. High freeness base paper has a significantly increased risk of breakdown due to enhanced pore connectivity. Figure 2As can be seen from the test results shown in Table 1, the increase in beating degree aggravates the anisotropy, the transverse tear resistance decreases by 18% (55±2°SR vs 25±2°SR), the fiber longitudinal arrangement is more compact, and the comprehensive mechanical properties are better at 40±2°SR: the tensile strength ratio is 0.82, and the transverse tear resistance is 260 mN; as can be seen from the test results shown in Table 2, the impregnation height is the highest (26 mm) at a high beating degree (55±2°SR), but the resin is prone to enrichment in the coarse pores, and forms stress concentration points after curing, and the impregnation rate and uniformity of the flat base paper at a beating degree of 40±2°SR are balanced, and the pore structure is suitable for uniform diffusion of the resin.

[0065] Referring to the performance test process of the flat base paper provided in Example 1, the flat base paper prepared by the orthogonal test preparation method provided in Example 2-3 is tested for performance.

[0066] Among them, the flat base paper provided in Example 2 has the highest electrical strength under the process combination of a hot pressing pressure of 10 MPa, a hot pressing temperature of 100°C, and a drying temperature of 90°C; the moderate hot pressing pressure promotes the close combination of fibers and improves the paper density; the appropriate hot pressing temperature helps the fiber softening and interweaving to form a more compact structure; the appropriate drying temperature ensures the stability of the internal structure of the paper, and the three synergistically improve the electrical insulation performance; when the hot pressing pressure is too low (5 MPa), the paper tightness is insufficient, and the internal pores are too many, which is not conducive to electrical insulation; when the hot pressing pressure is too high (15 MPa), the fiber is easily damaged, the fiber structure is destroyed, and the electrical strength is reduced;

[0067] When the hot pressing temperature is too low (80°C), the fiber softening is insufficient, and the combination is not tight; when the hot pressing temperature is too high (120°C), the fiber is decomposed or carbonized, affecting the electrical performance; when the drying temperature is too low (70°C), the paper is not dried completely, and the residual moisture affects the electrical insulation; when the drying temperature is too high (110°C), the paper is over-dried, the fiber is brittle, and the electrical strength is reduced.

[0068] As to the mechanical properties of the flat base paper provided in Example 2, the longitudinal tensile strength: reaches the maximum under the process combination of hot-pressing pressure of 15 MPa, hot-pressing temperature of 120℃ and drying temperature of 110℃; higher hot-pressing pressure and temperature make the fibers fully flocked and tightly combined, and higher drying temperature further enhances the binding force between the fibers, thereby increasing the longitudinal tensile strength; the transverse tear strength: performs better under the process combination of hot-pressing pressure of 5 MPa, hot-pressing temperature of 80℃ and drying temperature of 70℃. Lower hot-pressing pressure and temperature preserve the fiber length and flexibility, and lower drying temperature makes the paper structure relatively loose, so that a greater external force is needed for transverse tearing, and thus the transverse tear strength is higher; the longitudinal burst strength: is higher under the process combination of hot-pressing pressure of 10 MPa, hot-pressing temperature of 100℃ and drying temperature of 90℃, at which the fiber interweaving and combination state is good, and can withstand a larger pressure without breaking; as to the capillary impregnation: under the process combination of hot-pressing pressure of 5 MPa, hot-pressing temperature of 80℃ and drying temperature of 70℃, the capillary rise height is larger, and the capillary impregnation is better. Lower hot-pressing pressure and temperature make the internal pores of the paper larger, and lower drying temperature does not make the paper structure too dense, which is beneficial to the penetration of epoxy resin. With the increase of hot-pressing pressure, hot-pressing temperature and drying temperature, the paper structure gradually becomes tight, the pores become smaller, and the capillary impregnation gradually becomes worse.

[0069] On the basis of the performance of the flat base paper prepared by the orthogonal test preparation method provided in Example 2, in order to further improve the preparation process parameters of the flat base paper, a set of orthogonal test preparation methods of flat base paper are provided in Example 3, and the performance test is carried out by referring to the performance test process of the flat base paper provided in Example 1. The performance test results are shown in Table 4.

[0070] As can be seen from Table 4, through orthogonal test design and range analysis, combined with the interaction of hot-pressing pressure (9.0-11.0 MPa), hot-pressing temperature (90-110℃) and drying temperature (80-100℃) three factors, it is found that the range values of hot-pressing pressure on electrical strength, impregnation height and longitudinal tensile strength are 1.3 kV / mm, 5 mm and 7 N / mm respectively, which are significantly higher than the influence of other parameters, indicating that it is the core control variable; the synergistic effect of hot-pressing temperature and drying temperature is reflected in the matching of cellulose softening and water evaporation rate: when the hot-pressing temperature reaches 100-105℃, the fiber flocks fully, and the binding energy density increases to 3.2 J / m 2 ; the drying temperature is controlled at 90-95℃ to avoid fiber embrittlement, so that the water gradient and resin diffusion rate are dynamically balanced (D=1.8×10 -9 m 2 / s). The verification experiment shows that the combination of hot-pressing pressure 10 MPa, hot-pressing temperature 100°C, and drying temperature 90°C achieves the best performance, with electrical strength 17.0±0.2 kV / mm, impregnation height 22±1 mm, longitudinal tensile strength 65±1 N / mm, and CV value <1.5%. This parameter is verified by the NSGA-II algorithm, and reaches the global optimum of electrical strength (17.2 kV / mm), mechanical performance (65 N / mm), and energy consumption (drying temperature 90°C) in the Pareto frontier, providing a replicable process window for industrial production.

[0071] According to the method shown in Example 1, 10 batches (100 sheets each) were continuously produced, and the performance qualified rate and batch-to-batch electrical strength standard deviation were analyzed. The average performance qualified rate was 98.8%, the standard deviation was ±0.4%, and the batch-to-batch electrical strength standard deviation was ≤0.3 kV / mm.

[0072] The performance qualified rate standard is:

[0073] According to the method shown in Example 1, 10 batches (100 sheets each) were continuously produced, and the performance qualified rate and batch-to-batch electrical strength stability were analyzed. The performance qualified rate was the proportion of samples in a single batch that met all the following indicators:

[0074] Electrical strength ≥ 17.0 kV / mm (GB / T 1408.1-2016);

[0075] Longitudinal tensile strength ≥ 65 N / mm (GB / T 12914-2018);

[0076] Transverse tear strength ≥ 260 mN (GB / T 455-2002);

[0077] Impregnation uniformity score ≥ 4 / 5 (SEM observation of resin distribution without significant enrichment).

[0078] The above examples and experimental examples show that in the preparation process of flat base paper as the core raw material of electrical crepe paper, the flat base paper prepared by beating to a pulp target value of 35-45°SR and under the process combination of hot-pressing pressure 10 MPa, hot-pressing temperature 100°C, and drying temperature 90°C has excellent comprehensive performance in electrical, mechanical, and impregnation properties, and can meet the insulation requirements of dry bushings and other electrical equipment, overcoming the defects of low comprehensive performance of flat base paper prepared by existing processes.

[0079] Table 1: Performance test results (breakdown strength) of flat base paper provided by Example 1 and Comparative Examples 1-2

[0080]

[0081] Table 2: Performance test results of flat base paper provided by Example 1, Comparative Examples 1-2 (resin impregnation)

[0082]

[0083] Table 4: Process parameters and performance test results of a set of orthogonal test preparation methods of flat base paper provided by Example 3

[0084]

[0085] The above embodiments are only used to illustrate the technical solutions of the present application, rather than limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for producing a high performance flat base paper, characterized by, The method comprises the following steps: a step of beating pulp: soaking raw pulp board into water to form a pulp slurry and beating the pulp slurry using a PFI beater to obtain a pulp slurry with a beating degree of 35-45°SR; a step of papermaking: using a papermaking machine to make the pulp slurry with a beating degree of 35-45°SR into a wet paper sheet; a step of hot pressing: using a flat hot press to hot press the wet paper sheet under a hot pressing process of 9.0-11.0 MPa and 90-110°C to obtain a hot pressed paper; a step of drying: drying the hot pressed paper at a temperature of 80-100°C until the moisture content is ≤5wt% to obtain a high-performance flat base paper.

2. A process for the production of a high performance paperboard according to claim 1, characterized in that, In the step of beating pulp, the raw pulp board is selected from unbleached softwood pulp raw pulp board, the fiber length is 1.8-2.2mm, and the fiber width is 20-25μm.

3. The method for preparing a high-performance flat sheet paper according to claim 1, characterized in that, In the step of beating pulp, the process of beating the pulp slurry using a PFI beater includes: using a PFI beater to defibrate the pulp slurry with a concentration of 2-8wt% for 2-8min, and then beating the pulp slurry at a speed of 2000-4000rpm and a gap of 0.1-0.3mm to obtain a pulp slurry with a beating degree of 35-45°SR.

4. The method of claim 1, wherein the high performance plain paper is prepared by adding 0.1 to 1.0 wt% of the cationic polymer to the papermaking furnish. In the step of paper forming, the process of paper forming using a paper machine comprises: adjusting the consistency of the pulp with a beating degree of 35~45°SR to 0.2wt% by adding water, adjusting the amount of pulp to make the basis weight of the wet paper sheet 60±2g / m 2 and injecting into the forming wire of the paper machine, and dehydrating to 75~80% to obtain a wet paper sheet.

5. The method of claim 1, wherein the high performance plain paper is prepared by adding 0.1 to 1.0 wt% of the cationic polymer to the papermaking furnish. 5 In the step of hot-pressing, the process of hot-pressing the wet paper sheet includes: hot-pressing the wet paper sheet for 5-15 min to obtain a hot-pressed paper with a basis weight of 60±1 g / m 2 .

6. The method of claim 1, wherein the high performance paper sheet is a base paper for a plain paper printer. In the step of drying, the equipment used for drying is a circulating hot air drying oven.

7. A high performance flat sheet base paper characterized by, Prepared by the preparation method of any one of claims 1-6.

8. Use of the high-performance flat base paper of claim 7 in the field of electrical equipment insulation.

9. An electrical corrugated paper, wherein the raw material of the electrical corrugated paper comprises the high-performance flat base paper of claim 7.

10. Use of the electrical corrugated paper of claim 9 as an insulating material in an electrical environment with a voltage level of 110 kV-500 kV.

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