Insulating flame-retardant adhesive tape and preparation method thereof

Abstract

The invention belongs to the technical field of insulating flame-retardant adhesive tapes, and particularly relates to an insulating flame-retardant adhesive tape and a preparation method thereof. According to the invention, phytic acid reacts with 3-amino-5-methylpyrazole, triaminopyrimidine and polyether amine-2000 to prepare a flame-retardant auxiliary agent, and the flame-retardant auxiliary agent is compounded with magnesium hydroxide, zinc borate and melamine to prepare a modified flame retardant which can generate an expansive carbon layer during combustion to block heat and isolate oxygen so as to achieve a flame-retardant effect; an aluminum oxide layer generated on the artificial diamond micro-powder is used as an insulating heat-conducting aid, so that the insulativity, wear resistance and corrosion resistance of the insulating flame-retardant adhesive tape are improved, the adhesive tape can be assisted in uniform heat conduction, and combustion caused by over-high local temperature is prevented; epoxy resin is used for wrapping the uniformly dispersed insulating heat-conducting auxiliary agent, and anisyl and boron nitride ceramic powder are cured to prepare an insulating material, so that the dielectric breakdown performance of the adhesive tape is enhanced. The insulating flame-retardant adhesive tape prepared by the invention is excellent in insulativity and flame retardance and free of halogen flame retardants, and the production process is environment-friendly.

Description

Technical Field

[0001] The invention belongs to the technical field of insulating flame-retardant adhesive tapes, and in particular relates to an insulating flame-retardant adhesive tape and a preparation method thereof. Background Art

[0002] Adhesive tape consists of two parts: base material and adhesive. It connects two or more unconnected objects together through bonding. The base material of the adhesive tape can be polyethylene, polypropylene, paper, etc., and the adhesive material can be acrylic resin, butyl rubber, polyester resin, etc. However, these commonly used base materials and adhesive materials are all flammable materials. In order to make the adhesive tape have flame retardant and insulating properties, flame retardants and insulating agents need to be added to modify the tape.

[0003] The Chinese invention patent with publication number CN113930168B provides a flame-retardant insulating electrical tape, comprising a first adhesive layer 1 and a second adhesive layer 2 laminated together; the first adhesive layer 1 contains the following components by weight: 100 parts of chlorinated butyl rubber, 10-20 parts of POE elastomer, 3-10 parts of liquid polyisobutylene, 5-15 parts of fumed white carbon black, 100-150 parts of hydrophobic aluminum hydroxide, 15-30 parts of decabromodiphenylethane, 5-10 parts of liquid chlorinated paraffin, 5-10 parts of trioctyl phosphate, 0.5-2 parts of alkane coupling agent, and 2-5 parts of antioxidant. The Chinese invention patent with publication number CN115926638B discloses a flame-retardant waterproof insulating composite tape, comprising an upper adhesive layer and a lower backing. The upper adhesive layer is composed of butyl rubber, magnesium hydroxide, decabromodiphenylethane, silicon micropowder, silicon magnesium powder, polyisobutylene, carbon black, and stearic acid; the lower backing layer is composed of ethylene propylene rubber, butyl rubber, chlorinated polyethylene, polyisobutylene, magnesium hydroxide, decabromodiphenylethane, silicon micropowder, silicon magnesium powder, chlorinated paraffin, carbon black, stearic acid, and polyethylene wax. However, the existing technology has the technical problems of using halogen flame retardants, which is not environmentally friendly, and the adhesive layer of the tape is not adhesive enough. Summary of the invention

[0004] The purpose of the present invention is to provide an insulating flame retardant tape and a preparation method thereof, so as to solve the technical problems in the prior art that the use of halogen flame retardants is not environmentally friendly and the adhesive layer of the tape has insufficient adhesion.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions: An insulating flame-retardant adhesive tape comprises a base film layer, an adhesive layer, a flame-retardant adhesive layer, an insulating adhesive layer and an isolation film layer in sequence from top to bottom.

[0006] The base film layer is composed of the following components, in parts by mass: 60-70 parts of high-density polyethylene, 30-40 parts of low-density polyethylene, 0.5-2 parts of antioxidant and 1-5 parts of lubricant; The adhesive layer is composed of the following components, in parts by mass: 60-70 parts of hydroxy acrylic resin, 30-40 parts of methacrylic resin, 0.5-2 parts of defoaming agent and 0.5-2 parts of leveling agent; The isolation film layer is one or more combinations of a polyethylene isolation film layer, a polypropylene isolation film layer and a polyester isolation film layer; The flame retardant rubber layer is composed of the following components, in parts by mass: 30-50 parts of butyl rubber, 20-30 parts of styrene-butadiene rubber, 15-25 parts of modified flame retardant, 1-5 parts of coupling agent, 0.5-2 parts of antioxidant and 30-50 parts of filler; The insulating rubber layer is composed of the following components, in parts by mass: 30-50 parts of butyl rubber, 20-30 parts of EPDM rubber, 15-30 parts of insulating material, 1-5 parts of coupling agent, 0.5-2 parts of antioxidant and 30-50 parts of filler.

[0007] Preferably, the antioxidants of the base film layer, the flame retardant adhesive layer and the insulating adhesive layer are all one or more combinations of 168, 1010 and 1076.

[0008] Preferably, the lubricant of the base film layer is one or a combination of polyethylene wax, sodium stearate and polyethylene glycol.

[0009] Preferably, the defoaming agent of the adhesive layer is one or more combinations of BYK-021, BYK-028 and BYK-A530, and the leveling agent is one or more combinations of ASK-191, LD-9601 and LB-575.

[0010] Preferably, the coupling agents of the flame retardant adhesive layer and the insulating adhesive layer are one or more combinations of KH-550, KH-560, KH-570 and KH-590.

[0011] Preferably, the fillers of the flame retardant adhesive layer and the insulating adhesive layer are one or more combinations of fumed silica, calcium carbonate and montmorillonite.

[0012] A method for preparing an insulating flame-retardant tape comprises the following steps: S1. Preparation of base film layer: weigh the materials used for the base film layer, add the weighed materials into a high-speed mixer and mix for 10-20 minutes, add them into an extruder for extrusion and calendering, and control the thickness to be 0.2-0.5 mm to obtain a base film layer; S2. Preparation of bonding layer material: weigh the materials used for the bonding layer, add hydroxy acrylic resin and methacrylic resin into deionized water for dilution, add leveling agent and defoaming agent and stir evenly to obtain bonding layer material; S3, preparation of adhesive mortar: weigh the materials used for the flame retardant adhesive layer and the insulating adhesive layer respectively, mix the materials used for the flame retardant adhesive layer and the insulating adhesive layer respectively, and then mix them into sheets through an open mill and a mixer, crush and granulate them, add an organic solvent, stir at 70-85°C until there is no colloidal solid, and let it stand for 24 hours to obtain a flame retardant adhesive mortar and an insulating adhesive mortar; S4, glue coating: After the base film layer is coated with the adhesive layer material through the composite molding machine, the flame retardant glue and the insulating glue are coated in sequence, composite molding is performed, and the film is wound up by the guide roller; S5, applying the isolation film layer: after roller cooling, applying the isolation film layer, controlling the thickness to be 1.4~1.8mm, and winding it by the traction machine to obtain a large roll of insulating flame-retardant tape; S6. Cutting and packaging: Put the large roll of insulating flame retardant tape into the slitting machine for cutting and packaging to obtain the insulating flame retardant tape product.

[0013] Preferably, the feed inlet temperature of the extruder in S1 is 130-150°C, and the extrusion outlet temperature is 160-180°C.

[0014] Preferably, deionized water is added to dilute the S2 to a total acrylic resin content of 30-50 wt %.

[0015] Preferably, the organic solvent in S3 is one or more combinations of n-hexane, n-propanol and isopropanol.

[0016] Preferably, the starting temperature of the flame retardant adhesive layer in S3 is 120-150°C, and the mixing temperature is 140-160°C; the starting temperature of the insulating adhesive layer is 140-160°C, and the mixing temperature is 160-180°C.

[0017] Preferably, the method for preparing the modified flame retardant comprises the following steps: S11, dissolving 3-amino-5-methylpyrazole in deionized water, adding phytic acid, reacting at 110-150° C. for 1-2 h, then adding triaminopyrimidine, reacting at 120-150° C. for 1-2 h, and drying to obtain a mixture 1; S12, adding mixture 1 to polyetheramine-2000 solution, reacting at 60-70° C. for 1-2 hours, and drying to obtain a flame retardant additive; S13, stirring the flame retardant additive with magnesium hydroxide, zinc borate and melamine for 10 to 20 minutes to obtain a modified flame retardant.

[0018] Preferably, the modified flame retardant comprises, by mass, 10 to 20 parts of 3-amino-5-methylpyrazole, 10 to 50 parts of triaminopyrimidine, 100 parts of deionized water, 10 to 15 parts of phytic acid, 10 to 20 parts of polyetheramine-2000 solution, 5 to 25 parts of magnesium hydroxide, 5 to 25 parts of zinc borate and 10 to 15 parts of melamine.

[0019] Preferably, the reaction mechanism involved in the flame retardant additive is as follows:

[0020] Wherein R1 represents the remaining part of phytic acid except the phosphoric acid group, R2 represents the remaining part of 3-amino-5-methylpyrazole, triaminopyrimidine and polyetheramine-2000 except the amino group, the amino groups in 3-amino-5-methylpyrazole and triaminopyrimidine react with the carboxyl groups on multiple phosphoric acid groups in phytic acid to synthesize a mixture with multiple phosphoramide groups, and the introduction of nitrogen-rich groups can increase the thermal stability and mechanical properties of the material. During combustion, phytic acid decomposes to generate phosphoric acid, which catalyzes triaminopyrimidine and 3-amino-5-methylpyrazole to generate a large amount of nitrogen and water vapor during the combustion process, and reacts with the polymer matrix to form an expanded carbon layer, thereby achieving a flame retardant effect.

[0021] Preferably, the method for preparing the insulating material comprises the following steps: S21, adding anisil and boron nitride ceramic powder to an insulating thermal conductive additive, stirring for 10 to 15 minutes to obtain an insulating mixed powder; S22. Add the insulating mixed powder into the epoxy resin, stir and mix evenly, add the polyetheramine curing agent, cure at 50-60°C for 3-4 hours, and crush and granulate to obtain the insulating material.

[0022] Preferably, the insulating material comprises 30-50 parts of insulating thermal conductive additive, 10-20 parts of anisil, 20-30 parts of boron nitride ceramic powder, 50-60 parts of epoxy resin, and 20-40 parts of polyetheramine curing agent in parts by mass.

[0023] Preferably, the particle size of the boron nitride ceramic powder in S21 is between 10 and 20 μm.

[0024] Preferably, the method for preparing the insulating thermal conductive additive comprises the following steps: S31, adding artificial diamond powder and surfactant into deionized water, and ultrasonically dispersing at 70-80° C. for 10-30 min to obtain a suspension; S32. Keep the suspension at 75-80°C, add 10wt% aluminum nitrate solution while stirring, and simultaneously add 10wt% sodium hydroxide solution to maintain the pH of the system at 6-7. After the aluminum nitrate solution is added within 1-2 hours, continue stirring and reacting for 2-3 hours. After filtering and drying, calcine at 600-700°C for 3-4 hours to obtain an insulating thermal conductive additive.

[0025] Preferably, the insulating and thermally conductive additive comprises 5 to 10 parts of artificial diamond powder, 1 to 5 parts of a surfactant, 15 to 20 parts of an aluminum nitrate solution and 100 parts of deionized water, respectively.

[0026] Preferably, the particle size of the artificial diamond powder in S31 is between 0.1 and 5 μm.

[0027] Preferably, the surfactant in S31 is one or more combinations of sodium cetyl sulfate, polyoxyethylene lauryl alcohol ether and lauryl amide propyl betaine.

[0028] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are: 1. Based on the prior art, the present invention optimizes the composition and preparation process of the flame-retardant adhesive layer and the insulating adhesive layer, and the prepared insulating flame-retardant adhesive tape has not only strong adhesion, but also good flexibility and mechanical properties. The butyl rubber and styrene-butadiene rubber are used as the flame-retardant adhesive layer substrates, and the tape has excellent heat resistance and air tightness. The butyl rubber and EPDM rubber are used as the insulating adhesive layer substrates, and the tape has excellent heat resistance and air tightness as well as excellent chemical corrosion resistance and weather resistance. The insulating flame-retardant adhesive tape prepared by the present invention does not contain halogen flame retardants, and the production process is environmentally friendly.

[0029] 2. The present invention grafts 3-amino-5-methylpyrazole and triaminopyrimidine onto phytic acid through reaction. The flame retardant additive combined by the reaction of phytic acid and polyetheramine is a good acid source and carbon source. The flame retardant additive is compounded with gas source melamine to generate an expanded carbon layer during combustion to block heat and isolate oxygen to achieve a flame retardant effect. Polyetheramine-2000 loads nitrogen-rich groups and phytic acid through an amidation reaction, so that the nitrogen-rich groups and phytic acid are more evenly dispersed in the adhesive layer and have higher interface compatibility. Zinc borate can cover the surface of the expanded carbon layer with a glass protective layer to improve the density and thermal insulation of the carbon layer.

[0030] 3. The present invention generates a layer of dense aluminum oxide on artificial diamond powder as an insulating and thermal conductive auxiliary agent, which can not only improve the insulation, wear resistance and corrosion resistance of the insulating flame-retardant tape, but also assist the tape in uniformly conducting heat, prevent the tape from burning due to excessive local temperature, and make the insulating adhesive layer have certain flame retardant properties.

[0031] 4. The insulating material of the present invention is prepared by curing a uniformly dispersed insulating thermal conductive agent, anisil and boron nitride ceramic powder wrapped with epoxy resin. The epoxy resin wrapping anisil prevents the effective ingredient from migrating out and escaping during the production process of the tape, and can improve the local discharge starting voltage and extinction voltage of the tape, and to a certain extent slow down the growth rate of electrical trees on the tape. The insulating thermal conductive agent, anisil and boron nitride ceramic powder are compounded to enhance the dielectric breakdown performance of the tape. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0033] Figure 1 A schematic diagram of the hierarchical structure of an insulating flame-retardant tape of the present invention is shown.

[0034] Description of main reference numerals: 1-base material layer, 2-adhesive layer, 3-flame retardant adhesive layer, 4-insulating adhesive layer, 5-isolating film layer. DETAILED DESCRIPTION

[0035] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0036] Example 1, see Figure 1 As shown, an insulating flame-retardant adhesive tape of this embodiment is provided with a base film layer 1, an adhesive layer 2, a flame-retardant adhesive layer 3, an insulating adhesive layer 4 and an isolation film layer 5 in sequence from top to bottom.

[0037] The base film layer is composed of the following components, in parts by mass: 60 parts of high-density polyethylene, 40 parts of low-density polyethylene, 2 parts of antioxidant and 3 parts of lubricant; The adhesive layer is composed of the following components, in parts by mass: 65 parts of hydroxy acrylic resin, 35 parts of methacrylic resin, 1 part of defoaming agent and 1 part of leveling agent; The isolation film layer is a polyethylene isolation film layer; The flame retardant rubber layer is composed of the following components, in parts by mass: 30 parts of butyl rubber, 30 parts of styrene-butadiene rubber, 20 parts of modified flame retardant, 3 parts of coupling agent, 2 parts of antioxidant and 30 parts of filler; The insulating rubber layer is composed of the following components, in parts by mass: 30 parts of butyl rubber, 20 parts of EPDM rubber, 20 parts of insulating material, 3 parts of coupling agent, 1 part of antioxidant and 30 parts of filler.

[0038] The antioxidant model of the base film layer, flame retardant adhesive layer and insulating adhesive layer is 168; the lubricant of the base film layer is polyethylene wax; the defoaming agent of the adhesive layer is BYK-021, and the leveling agent is ASK-191; the coupling agent model of the flame retardant adhesive layer and the insulating adhesive layer is KH-550; the fillers of the flame retardant adhesive layer and the insulating adhesive layer are both fumed silica.

[0039] A method for preparing an insulating flame-retardant tape according to the present embodiment comprises the following steps: S1. Preparation of base film layer: weigh the materials used for the base film layer, add the weighed materials into a high-speed mixer and mix for 10 minutes, add them into an extruder for extrusion and calendering, and control the thickness to 0.2 mm to obtain a base film layer; S2. Preparation of bonding layer material: weigh the materials used for the bonding layer, add hydroxy acrylic resin and methacrylic resin into deionized water to dilute the total content of acrylic resin to 40wt%, add leveling agent and defoaming agent and stir evenly to obtain bonding layer material; S3, preparation of adhesive mortar: weigh the materials used for the flame retardant adhesive layer and the insulating adhesive layer respectively, mix the materials used for the flame retardant adhesive layer and the insulating adhesive layer respectively, and then pass through an open mill and a mixer. The open milling temperature of the flame retardant adhesive layer is 130°C, and the mixing temperature is 150°C. The open milling temperature of the insulating adhesive layer is 150°C, and the mixing temperature is 170°C. After mixing into sheets, crush and granulate, add n-hexane, stir at 75°C until there is no colloidal solid, and let stand for 24 hours to obtain flame retardant adhesive mortar and insulating adhesive mortar; S4, glue coating: After the base film layer is coated with the adhesive layer material through the composite molding machine, the flame retardant glue and the insulating glue are coated in sequence, composite molding is performed, and the film is wound up by the guide roller; S5, applying an isolation film layer: after roller cooling, applying an isolation film layer, controlling the thickness to be 1.4 mm, and winding it through a traction machine to obtain a large roll of insulating flame-retardant tape; S6. Cutting and packaging: Put the large roll of insulating flame retardant tape into the slitting machine for cutting and packaging to obtain the insulating flame retardant tape product.

[0040] The preparation method of the modified flame retardant of this embodiment comprises the following steps: S11, dissolving 10 parts of 3-amino-5-methylpyrazole in deionized water, adding 10 parts of phytic acid, reacting at 130° C. for 2 h, then adding 50 parts of triaminopyrimidine, reacting at 150° C. for 2 h, and drying to obtain a mixture 1; S12, adding mixture 1 to 10 parts of polyetheramine-2000 solution, reacting at 70° C. for 2 hours, and drying to obtain a flame retardant additive; S13, mixing the flame retardant auxiliary agent with 10 parts of magnesium hydroxide, 15 parts of zinc borate and 15 parts of melamine for 20 minutes to obtain a modified flame retardant.

[0041] The method for preparing the insulating material of this embodiment includes the following steps: S21, adding 30 parts of insulating thermal conductive additives to 15 parts of anisil and 25 parts of 10 μm boron nitride ceramic powder, stirring for 15 minutes to obtain an insulating mixed powder; S22, adding the insulating mixed powder into 50 parts of epoxy resin, stirring and mixing evenly, adding 30 parts of polyetheramine-650 curing agent, curing at 60°C for 3 hours, and crushing and granulating to obtain insulating material.

[0042] The preparation method of the insulating thermal conductive additive of this embodiment comprises the following steps: S31, adding 7 parts of artificial diamond powder and 2 parts of sodium hexadecyl sulfate to 100 parts of deionized water, and dispersing them ultrasonically at 70° C. for 20 minutes to obtain a suspension; S32. Keep the suspension at 70°C, add 15 parts of 10wt% aluminum nitrate solution while stirring, and at the same time add 10wt% sodium hydroxide solution to maintain the pH of the system at 7. After the aluminum nitrate solution is added within 2 hours, continue stirring and reacting for 2 hours. After filtering and drying, calcine at 700°C for 3 hours to obtain an insulating thermal conductive additive.

[0043] Example 2, see Figure 1 As shown, an insulating flame-retardant adhesive tape of this embodiment is provided with a base film layer 1, an adhesive layer 2, a flame-retardant adhesive layer 3, an insulating adhesive layer 4 and an isolation film layer 5 in sequence from top to bottom.

[0044] The base film layer is composed of the following components, in parts by mass: 70 parts of high-density polyethylene, 30 parts of low-density polyethylene, 2 parts of antioxidant and 5 parts of lubricant; The adhesive layer is composed of the following components, in parts by mass: 60 parts of hydroxy acrylic resin, 40 parts of methacrylic resin, 2 parts of defoaming agent and 2 parts of leveling agent; The isolation film layer is a polyester isolation film layer; The flame retardant rubber layer is composed of the following components, in parts by mass: 50 parts of butyl rubber, 20 parts of styrene-butadiene rubber, 25 parts of modified flame retardant, 3 parts of coupling agent, 1 part of antioxidant and 45 parts of filler; The insulating rubber layer is composed of the following components, in parts by mass: 50 parts of butyl rubber, 30 parts of EPDM rubber, 25 parts of insulating material, 3 parts of coupling agent, 1 part of antioxidant and 30 parts of filler.

[0045] The antioxidant model of the base film layer, flame retardant adhesive layer and insulating adhesive layer is 1076; the lubricant of the base film layer is polyethylene wax; the defoaming agent of the adhesive layer is BYK-028, and the leveling agent is LD-9601; the coupling agent model of the flame retardant adhesive layer and the insulating adhesive layer is KH-570; the fillers of the flame retardant adhesive layer and the insulating adhesive layer are calcium carbonate.

[0046] A method for preparing an insulating flame-retardant tape according to the present embodiment comprises the following steps: S1. Preparation of base film layer: weigh the materials used for the base film layer, add the weighed materials into a high-speed mixer and mix for 15 minutes, add the materials into an extruder for extrusion and calendering, and control the thickness to 0.4 mm to obtain a base film layer; S2. Preparation of bonding layer material: weigh the materials used for the bonding layer, add hydroxy acrylic resin and methacrylic resin into deionized water to dilute the total content of acrylic resin to 30wt%, add leveling agent and defoaming agent and stir evenly to obtain bonding layer material; S3, preparation of adhesive mortar: weigh the materials used for the flame retardant adhesive layer and the insulating adhesive layer respectively, mix the materials used for the flame retardant adhesive layer and the insulating adhesive layer respectively, and then pass through an open mill and a mixer. The open milling temperature of the flame retardant adhesive layer is 125°C, and the mixing temperature is 155°C. The open milling temperature of the insulating adhesive layer is 155°C, and the mixing temperature is 175°C. After mixing into sheets, crush and granulate, add n-propanol, stir at 80°C until there is no colloidal solid, and let stand for 24 hours to obtain flame retardant adhesive mortar and insulating adhesive mortar; S4, glue coating: After the base film layer is coated with the adhesive layer material through the composite molding machine, the flame retardant glue and the insulating glue are coated in sequence, composite molding is performed, and the film is wound up by the guide roller; S5, applying an isolation film layer: after roller cooling, applying an isolation film layer, controlling the thickness to be 1.8 mm, and winding it through a traction machine to obtain a large roll of insulating flame-retardant tape; S6. Cutting and packaging: Put the large roll of insulating flame retardant tape into the slitting machine for cutting and packaging to obtain the insulating flame retardant tape product.

[0047] The preparation method of the modified flame retardant of this embodiment is the same as that of embodiment 1.

[0048] The insulating material of this embodiment is different from that of Embodiment 1 in that the substances used in the insulating material are changed to 50 parts of insulating thermal conductive additive, 20 parts of anisil, 20 parts of boron nitride ceramic powder, 60 parts of epoxy resin, and 30 parts of polyetheramine D-230 curing agent in parts by mass.

[0049] The preparation method of the insulating thermal conductive additive of this embodiment is the same as that of embodiment 1.

[0050] Example 3, see Figure 1 As shown, an insulating flame-retardant adhesive tape of this embodiment is provided with a base film layer 1, an adhesive layer 2, a flame-retardant adhesive layer 3, an insulating adhesive layer 4 and an isolation film layer 5 in sequence from top to bottom.

[0051] The base film layer is composed of the following components, in parts by mass: 65 parts of high-density polyethylene, 35 parts of low-density polyethylene, 0.5 parts of antioxidant and 2 parts of lubricant; The adhesive layer is composed of the following components, in parts by mass: 70 parts of hydroxy acrylic resin, 30 parts of methacrylic resin, 0.5 parts of defoaming agent and 0.5 parts of leveling agent; The isolation film layer is a polypropylene isolation film layer; The flame retardant rubber layer is composed of the following components, in parts by mass: 30 parts of butyl rubber, 30 parts of styrene-butadiene rubber, 20 parts of modified flame retardant, 3 parts of coupling agent, 2 parts of antioxidant and 30 parts of filler; The insulating rubber layer is composed of the following components, in parts by mass: 30 parts of butyl rubber, 20 parts of EPDM rubber, 20 parts of insulating material, 3 parts of coupling agent, 1 part of antioxidant and 30 parts of filler.

[0052] The antioxidant model of the base film layer, flame retardant adhesive layer and insulating adhesive layer is 1010; the lubricant of the base film layer is sodium stearate; the defoaming agent of the adhesive layer is BYK-A530, and the leveling agent is LB-575; the coupling agent model of the flame retardant adhesive layer and the insulating adhesive layer is KH-560; the fillers of the flame retardant adhesive layer and the insulating adhesive layer are montmorillonite.

[0053] A method for preparing an insulating flame-retardant tape according to the present embodiment comprises the following steps: S1. Preparation of base film layer: weigh the materials used for the base film layer, add the weighed materials into a high-speed mixer and mix for 10 minutes, add them into an extruder for extrusion and calendering, and control the thickness to 0.3 mm to obtain a base film layer; S2. Preparation of bonding layer material: weigh the materials used for the bonding layer, add hydroxy acrylic resin and methacrylic resin into deionized water to dilute the total content of acrylic resin to 40wt%, add leveling agent and defoaming agent and stir evenly to obtain bonding layer material; S3, preparation of adhesive mortar: weigh the materials used for the flame retardant adhesive layer and the insulating adhesive layer respectively, mix the materials used for the flame retardant adhesive layer and the insulating adhesive layer respectively, and then pass through an open mill and a mixer. The open milling temperature of the flame retardant adhesive layer is 150°C, and the mixing temperature is 160°C. The open milling temperature of the insulating adhesive layer is 160°C, and the mixing temperature is 180°C. After mixing into sheets, crush and granulate, add isopropyl alcohol, stir at 70°C until there is no colloidal solid, and let stand for 24 hours to obtain flame retardant adhesive mortar and insulating adhesive mortar; S4, glue coating: After the base film layer is coated with the adhesive layer material through the composite molding machine, the flame retardant glue and the insulating glue are coated in sequence, composite molding is performed, and the film is wound up by the guide roller; S5, applying an isolation film layer: after roller cooling, applying an isolation film layer, controlling the thickness to be 1.6 mm, and winding it through a traction machine to obtain a large roll of insulating flame-retardant tape; S6. Cutting and packaging: Put the large roll of insulating flame retardant tape into the slitting machine for cutting and packaging to obtain the insulating flame retardant tape product.

[0054] The modified flame retardant of this embodiment is different from that of Example 1 in that the substances used in the modified flame retardant are changed to 20 parts of 3-amino-5-methylpyrazole, 40 parts of triaminopyrimidine, 100 parts of deionized water, 15 parts of phytic acid, 10 parts of polyetheramine-2000 solution, 25 parts of magnesium hydroxide, 5 parts of zinc borate and 10 parts of melamine in parts by mass.

[0055] The preparation method of the insulating material and the insulating thermal conductive additive of this embodiment is the same as that of Embodiment 1.

[0056] Comparative Example 1: The difference between this comparative example and Example 1 is that the 3-amino-5-methylpyrazole and triaminopyrimidine components in the modified flame retardant are replaced by diethylenetriamine.

[0057] Comparative Example 2: This comparative example differs from Example 1 in that the insulating materials are directly blended and prepared without adding epoxy resin and curing agent for curing.

[0058] Comparative Example 3: This comparative example differs from Example 1 in that the insulating and thermally conductive auxiliary agent is replaced with alumina micropowder.

[0059] Performance Testing Mechanical properties test The tensile strength and elongation at break of the adhesive tapes prepared in the examples and comparative examples were measured according to GB / T 528-2009 “Determination of tensile stress-strain properties of vulcanized rubber or thermoplastic rubber”.

[0060] The peel strength of the adhesive tapes prepared in each example and comparative example was measured according to GB / T 2792-2014 “Test method for peel strength of adhesive tapes”.

[0061] The test results are shown in Table 1 below: Table 1 Serial number Tensile strength (MPa) Elongation at break (%) Adhesive tape peel strength (N / cm) Example 1 17.1 416 23.7 Example 2 16.8 413 22.6 Example 3 16.6 415 23.4 Comparative Example 1 15.2 378 20.9 Comparative Example 2 16.1 409 23.7 Comparative Example 3 16.3 414 21.1 Flame retardant performance test The limiting oxygen index of the adhesive tapes prepared in the examples and comparative examples was measured according to GB / T 10707-2008 “Determination of Combustion Performance of Rubber”.

[0062] The flame retardancy rating of the adhesive tapes prepared in each embodiment and comparative example was determined according to UL 94-2020 “Combustibility Tests for Plastic Materials for Equipment and Electrical Parts”.

[0063] The test results are shown in Table 2 below: Table 2 Serial number Limiting oxygen index (%) Flame retardant grade Example 1 32.9 V-0 Example 2 33.6 V-0 Example 3 33.1 V-0 Comparative Example 1 25.7 V-1 Comparative Example 2 31.7 V-0 Comparative Example 3 30.4 V-0 Insulation performance test The breakdown voltage strength of the adhesive tapes prepared in the examples and comparative examples was measured according to GB / T 1695-2005 “Method for determination of power frequency breakdown voltage strength and withstand voltage of vulcanized rubber”.

[0064] The volume resistivity of the adhesive tapes prepared in the examples and comparative examples was measured according to GB / T 1692-2008 “Determination of insulation resistivity of vulcanized rubber”.

[0065] The test results are shown in Table 3 below: Table 3 Serial number Breakdown voltage strength (kV / mm) Volume resistivity (Ω×mm) Example 1 25.7 <![CDATA[4.5×10 15 ]]> Example 2 26.1 <![CDATA[4.7×10 15 ]]> Example 3 26.2 <![CDATA[4.6×10 15 ]]> Comparative Example 1 23.1 <![CDATA[3.4×10 15 ]]> Comparative Example 2 21.4 <![CDATA[6.9×10 14 ]]> Comparative Example 3 23.6 <![CDATA[7.1×10 14 ]]> According to the above table data, the tensile strength of the tapes prepared in Examples 1 to 3 is between 16.6 and 17.1 MPa, the elongation at break is between 413 and 416%, and the peel strength of the adhesive tape is between 22.6 and 23.7 N / cm, indicating that the tapes prepared in the present invention have good mechanical properties and strong adhesive force; the limiting oxygen index is between 32.9 and 33.6%, and the flame retardant grade is V-0, indicating that the tapes prepared in the present invention have excellent flame retardant properties; the breakdown voltage strength is between 25.7 and 26.3 kV / mm, and the volume resistivity is between 4.5×10 15 ~4.7×10 15 Ω×mm, indicating that the adhesive tape prepared by the present invention has excellent dielectric breakdown performance and insulation performance. Comparative Example 1 Since the 3-amino-5-methylpyrazole and triaminopyrimidine components in the modified flame retardant are changed to diethylenetriamine, the rubber in the adhesive layer reacts with diethylenetriamine, causing the adhesive layer to become brittle, so the tensile strength, elongation at break and peel strength of the adhesive tape of Comparative Example 1 are the lowest.

[0066] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

[0067] The preferred embodiments of the present invention disclosed above are only used to help explain the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to only specific implementation methods. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. An insulating flame-retardant tape, characterized in that: A base film layer (1), an adhesive layer (2), a flame retardant adhesive layer (3), an insulating adhesive layer (4) and an isolation film layer (5) are sequentially arranged from top to bottom; The base film layer is composed of the following components, in parts by mass: 60-70 parts of high-density polyethylene, 30-40 parts of low-density polyethylene, 0.5-2 parts of antioxidant and 1-5 parts of lubricant; The adhesive layer is composed of the following components, in parts by mass: 60-70 parts of hydroxy acrylic resin, 30-40 parts of methacrylic resin, 0.5-2 parts of defoaming agent and 0.5-2 parts of leveling agent; The isolation film layer is one or more combinations of a polyethylene isolation film layer, a polypropylene isolation film layer and a polyester isolation film layer; The flame retardant rubber layer is composed of the following components, in parts by mass: 30-50 parts of butyl rubber, 20-30 parts of styrene-butadiene rubber, 15-25 parts of modified flame retardant, 1-5 parts of coupling agent, 0.5-2 parts of antioxidant and 30-50 parts of filler; The insulating rubber layer is composed of the following components, in parts by mass: 30-50 parts of butyl rubber, 20-30 parts of EPDM rubber, 15-30 parts of insulating material, 1-5 parts of coupling agent, 0.5-2 parts of antioxidant and 30-50 parts of filler.

2. The flame-retardant insulating tape according to claim 1, characterized in that: The antioxidants of the base film layer, flame retardant adhesive layer and insulating adhesive layer are all one or more combinations of 168, 1010 and 1076; the lubricant of the base film layer is one or more combinations of polyethylene wax, sodium stearate and polyethylene glycol; the defoaming agent of the adhesive layer is one or more combinations of BYK-021, BYK-028 and BYK-A530, and the leveling agent is one or more combinations of ASK-191, LD-9601 and LB-575; the coupling agents of the flame retardant adhesive layer and the insulating adhesive layer are all one or more combinations of KH-550, KH-560, KH-570 and KH-590; the fillers of the flame retardant adhesive layer and the insulating adhesive layer are all one or more combinations of fumed silica, calcium carbonate and montmorillonite.

3. The flame-retardant insulating tape according to claim 1, characterized in that: The preparation method of the modified flame retardant comprises the following steps: S11, dissolving 3-amino-5-methylpyrazole in deionized water, adding phytic acid, reacting at 110-150° C. for 1-2 h, then adding triaminopyrimidine, reacting at 120-150° C. for 1-2 h, and drying to obtain a mixture 1; S12, adding mixture 1 to polyetheramine-2000 solution, reacting at 60-70° C. for 1-2 hours, and drying to obtain a flame retardant additive; S13, stirring the flame retardant additive with magnesium hydroxide, zinc borate and melamine for 10 to 20 minutes to obtain a modified flame retardant.

4. The flame-retardant insulating tape according to claim 3, characterized in that: The modified flame retardant comprises, by mass, 10 to 20 parts of 3-amino-5-methylpyrazole, 10 to 50 parts of triaminopyrimidine, 100 parts of deionized water, 10 to 15 parts of phytic acid, 10 to 20 parts of polyetheramine-2000 solution, 5 to 25 parts of magnesium hydroxide, 5 to 25 parts of zinc borate and 10 to 15 parts of melamine.

5. The flame-retardant insulating tape according to claim 1, characterized in that: The method for preparing the insulating material comprises the following steps: S21, adding anisil and boron nitride ceramic powder to an insulating thermal conductive additive, stirring for 10 to 15 minutes to obtain an insulating mixed powder; S22. Add the insulating mixed powder into the epoxy resin, stir and mix evenly, add the polyetheramine curing agent, cure at 50-60°C for 3-4 hours, and crush and granulate to obtain the insulating material.

6. The flame-retardant insulating tape according to claim 5, characterized in that: The substances used in the insulating material are 30-50 parts of insulating thermal conductive additive, 10-20 parts of anisil, 20-30 parts of boron nitride ceramic powder, 50-60 parts of epoxy resin, and 20-40 parts of polyetheramine curing agent, respectively. The particle size of the boron nitride ceramic powder in S21 is between 10 and 20 μm.

7. The flame-retardant insulating tape according to claim 5, characterized in that: The preparation method of the insulating thermal conductive additive comprises the following steps: S31, adding artificial diamond powder and surfactant into deionized water, and ultrasonically dispersing at 70-80° C. for 10-30 min to obtain a suspension; S32. Keep the suspension at 75-80°C, add 10wt% aluminum nitrate solution while stirring, and simultaneously add 10wt% sodium hydroxide solution to maintain the pH of the system at 6-7. After the aluminum nitrate solution is added within 1-2 hours, continue stirring and reacting for 2-3 hours. After filtering and drying, calcine at 600-700°C for 3-4 hours to obtain an insulating thermal conductive additive.

8. The flame-retardant insulating tape according to claim 7, characterized in that: The materials used in the insulating and thermally conductive additive are 5-10 parts of artificial diamond micropowder, 1-5 parts of surfactant, 15-20 parts of aluminum nitrate solution and 100 parts of deionized water in parts by mass; the particle size of the artificial diamond micropowder in S31 is between 0.1 and 5 μm, and the surfactant is one or more combinations of sodium hexadecyl sulfate, polyoxyethylene dodecanol and lauryl amide propyl betaine.

9. A method for preparing an insulating flame-retardant tape, characterized in that: The steps include: S1. Preparation of base film layer: weigh the materials used for the base film layer, add the weighed materials into a high-speed mixer and mix for 10-20 minutes, add them into an extruder for extrusion and calendering, and control the thickness to be 0.2-0.5 mm to obtain a base film layer; S2. Preparation of bonding layer material: weigh the materials used for the bonding layer, add hydroxy acrylic resin and methacrylic resin into deionized water for dilution, add leveling agent and defoaming agent and stir evenly to obtain bonding layer material; S3, preparation of adhesive mortar: weigh the materials used for the flame retardant adhesive layer and the insulating adhesive layer respectively, mix the materials used for the flame retardant adhesive layer and the insulating adhesive layer respectively, and then mix them into sheets through an open mill and a mixer, crush and granulate them, add an organic solvent, stir at 70-85°C until there is no colloidal solid, and let it stand for 24 hours to obtain a flame retardant adhesive mortar and an insulating adhesive mortar; S4, glue coating: After the base film layer is coated with the adhesive layer material through the composite molding machine, the flame retardant glue and the insulating glue are coated in sequence, composite molding is performed, and the film is wound up by the guide roller; S5, applying the isolation film layer: after roller cooling, applying the isolation film layer, controlling the thickness to be 1.4~1.8mm, and winding it by the traction machine to obtain a large roll of insulating flame-retardant tape; S6. Cutting and packaging: Put the large roll of insulating flame retardant tape into the slitting machine for cutting and packaging to obtain the insulating flame retardant tape product.

10. The method for preparing an insulating flame-retardant tape according to claim 9, characterized in that: The extruder feed port temperature of S1 is 130-150°C, and the extrusion port temperature is 160-180°C; deionized water is added to S2 to dilute the total content of acrylic resin to 30-50wt%; the organic solvent in S3 is one or more combinations of n-hexane, n-propanol and isopropanol, the start-up temperature of the flame retardant adhesive layer is 120-150°C, the mixing temperature is 140-160°C, the start-up temperature of the insulating adhesive layer is 140-160°C, and the mixing temperature is 160-180°C.

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