A fast-curing material for insulating a tower and a method for preparing the same

Abstract

The application discloses a polyurethane material for insulating a tower side and a preparation method thereof. 26 parts of functional fillers are added to 100 parts of a B component, and the functional fillers and a polyurethane A component are loaded into a feeding inlet of a spraying device. After being heated to 60 DEG C and being fully mixed, the material is sprayed through a nozzle and coated on a surface of a substrate to be treated. After being naturally maintained at room temperature for one week, the polyurethane material is obtained. The polyurethane spraying material has superior mechanical properties and electrical properties. Since the polyurethane spraying material can be sprayed, the polyurethane spraying material can be directly applied to substrates of various shapes without complex preparation work. The polyurethane spraying material has a fast forming speed, ensures construction efficiency, has a long service life, can meet long-term stable application requirements, and is not limited by scene applications.

Description

TECHNICAL FIELD

[0001] The present application relates to a kind of polyurethane material for tower side insulation and its preparation method, belong to polyurethane material technical field. BACKGROUND

[0002] Polyurethane (PU) is one of the most common, most widely used, most researched materials in the world. It can combine the durability and toughness of metal with the elasticity of rubber, making it a suitable replacement for several engineering products such as metal, plastic and rubber. Polyurethane materials have been used in various types of industrial equipment and used to manufacture a variety of application goods, commonly including, for example, paints, liquids, elastomers, rigid insulating materials, elastic fibers, soft foam, and even used as an integral skin. Polyurethane is made from a variety of diisocyanates, a variety of polyols, other chain extenders and crosslinking agents. Therefore, according to the different characteristics of the monomer, the polyurethane product with customized function can be prepared, which can meet the application in many specific situations. The performance advantages of polyurethane mainly include the following aspects:

[0003] (1) During the curing process of polyurethane film, a large number of urethane bonds and urea bonds are continuously formed in the molecular structure. The two chemical bonds promote the formation of hydrogen bonds between the molecules of the high polymer. The existence of a large number of hydrogen bonds improves the intermolecular cohesive energy, thereby enhancing the tear resistance of the coating. Therefore, compared with other types, under the joint action of several chemical bonds, polyurethane has excellent wear resistance and higher hardness. And because it has both protective and decorative advantages, it is widely used in external protective coatings of high-strength working machines, cargo deck paint, aircraft integral surface coating paint, etc. At the same time, under the action of external force, hydrogen bonds can be broken to absorb energy; when the external force disappears, hydrogen bonds can be regenerated. Therefore, the breaking and recovery of hydrogen bonds improve the wear resistance and toughness of polyurethane, which is also the principle of preparing self-repairing polyurethane.

[0004] (2) Polyurethane also has very excellent performance in oil resistance, chemical resistance, etc. After the coating is completely cured, it can still maintain the characteristics of not being contaminated and not being eroded in the environment of long-term contact with corrosive liquids, oil storage, and synthetic oils, etc. Therefore, most of the oil extraction storage tanks and corrosion-resistant liquid tank inner walls on the market currently use polyurethane for corrosion protection.

[0005] (3) Polyurethane has excellent substrate adhesion. It can be made into good performance sealant and adhesive. In practical application, except that the adhesion to individual metal surfaces is weaker than that of epoxy resin paint, it has excellent adhesion to the surfaces of various object substrates (such as metal, wood, glass, and some plastics).

[0006] (4) When polyurethane is used in combination with other resin paints, the combined characteristics of multiple varieties and multiple performances can be used to strengthen the comprehensive performance advantages and meet the use requirements under special application conditions. Secondly, by adjusting the ratio between various synthetic monomer components, the reasonable transformation between firm toughness and soft elasticity can be achieved. Compared with the single performance brought by the use of a certain resin alone, polyurethane has more application markets.

[0007] (5) The curing temperature range of polyurethane is very wide, which can be cured into a film at room temperature and at a higher temperature, or can be cured at a low temperature. Therefore, the application scenarios are rich, and can adapt to complex working environments. In the product cured at room temperature: the coating of epoxy resin and unsaturated polyester is difficult to cure completely at a room temperature below 10℃, even if the coating can be cured, the required period is long, and the mechanical properties of the product are poor. However, polyurethane can be rapidly cured at room temperature, and even at an environmental temperature of zero degrees and below, and the effect is excellent.

[0008] At present, the following problems exist in the sprayed insulation material:

[0009] ① Although the isolation type measure can effectively reduce the short circuit failure caused by the use of iron wire by birds to build nests or the wet bird nests, the types and appearances of actual wire clamps and other power devices are different, and the insulating protective cover is difficult to realize mass and unified production, resulting in high cost.

[0010] ② The material modified by the epoxy resin has a long curing time, and there is a dripping phenomenon after spraying, which leads to serious material loss and cannot form an insulating protective layer.

[0011] ③ Although the RTV coating used for insulator anti-pollution flashover can eliminate the difference in appearance of power devices, the principle of anti-pollution flashover is mainly the migration of hydrophobicity, and the purpose is not to effectively eliminate the short circuit failure caused by the use of conductor such as iron wire by birds to build nests or wet bird nests.

[0012] Therefore, the specific synthesis process of polyurethane is explored, the influence of each monomer component of polyurethane on the performance of the coating is investigated and demonstrated, and the characteristics of polyurethane are better applied to practice. SUMMARY

[0013] The purpose of the present application is to provide a kind of polyurethane material for tower side insulation and a preparation method thereof.

[0014] A kind of polyurethane material for tower side insulation and a preparation method thereof, comprising the following steps: 26 mass parts of functional filler are added to 100 mass parts of component B, and the polyurethane A component is loaded into the feed inlet of the spraying device together, heated to 60 DEG C and the material is fully mixed, then sprayed out through the nozzle, coated on the surface of the substrate to be treated, and naturally cured at room temperature for one week to obtain the polyurethane material.

[0015] Preferably, the polyurethane A component is that the hydroxyl-terminated butadiene-acrylonitrile copolymer (HTBN) is heated to 120 DEG C in a container, vacuum dewatering for 1h, then cooled to 60 DEG C, nitrogen is introduced, and hexamethylene diisocyanate (HDI) is added to react for 3h at 60 DEG C to obtain an isocyanate-terminated prepolymer, namely the polyurethane A component.

[0016] Preferably, the B component is a dihydric alcohol small molecule chain extender, which is composed of ethylene glycol, propylene glycol, 1,4-butanediol and 1,6-hexanediol in a mass ratio of 6:1.5:2:0.5.

[0017] Preferably, in the polyurethane A component, the number of moles of isocyanate of HDI is n, the number of moles of hydroxyl of HTBN is n1, and in the B component, the number of moles of hydroxyl of the dihydric alcohol small molecule chain extender is n2, n = n1 + n2.

[0018] Preferably, the functional filler is composed of 10 parts by mass of aluminum oxide nanoparticles, 1 part by mass of hydrophobic fumed silica nanoparticles, 5 parts by mass of high-purity boron nitride powder and 10 parts by mass of silane coupling agent.

[0019] Compared with the prior art, the present application has the following beneficial effects:

[0020] ① Since the present application adopts the spraying implementation method, the problem that the insulating protective cover is difficult to realize mass and unified production can be effectively solved, aiming at the different models and appearances of power devices.

[0021] ② The material designed by the present application has a fast molding speed and a short curing time, which can effectively solve the dripping problem after spraying and reduce the waste of materials.

[0022] ③ The material designed by the present application has a high breakdown voltage and can be used as an insulating material, which can effectively eliminate the short circuit failure caused by birds building nests with conductors such as iron wires or wet nests.

[0023] Compared with the traditional insulating sheath, the polyurethane spraying material in the present application has superior mechanical and electrical properties. Since it can be sprayed, it can be directly applied to substrates of various shapes without complex preparation work. The material has a fast molding speed, ensuring construction efficiency, and has a long service life, which can meet the long-term stable application requirements and is not limited by scene applications. Whether indoors or outdoors, the material can adapt and maintain good performance, and the formula ratio and construction method can be adjusted according to different needs and scenes, providing great flexibility for construction personnel. The material applied to power transmission towers can effectively reduce the occurrence of bird damage and foreign matter failures, further reducing maintenance costs. At the same time, the material has a fast curing time, avoiding the dripping phenomenon, maintaining the physical properties and aesthetics of the material, and having a wide application scene. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 Synthesis principle diagram of polyurethane material.

[0025] Figure 2 Structure diagram of polyurethane material spraying device for tower side insulation.

[0026] Figure 3 Scanning electron microscope (SEM) diagram of polyurethane film prepared in Example 1.

[0027] Figure 4 Contact angle diagram of polyurethane film prepared in Example 1. DETAILED DESCRIPTION

[0028] The application will be further described below in conjunction with the drawings and examples.

[0029] (I) Preparation of polyurethane material

[0030] The synthesis adopts a two-step method, HDI and HTBN are first reacted to obtain component A, component A is reacted with component B and functional filler to form polyurethane elastomer, and the principle is as shown in Figure 1 .

[0031] (II) Selection of fillers

[0032] Inorganic nano-aluminum oxide particles prepared by gas phase method are doped into polyurethane composite to improve its thermal conductivity and insulation performance, which can prevent the damage to power devices or surrounding cured products caused by heat release of polyurethane during curing, and improve the insulation capacity of the insulation layer after the mixture is cured. When a small amount of particles are doped, the interaction thickness between spherical nanoparticles and the polyurethane matrix will be less than the free travel of charge carriers, which inhibits the migration of charge carriers, and further increases the breakdown field strength.

[0033] Hydrophobic nano-silicon dioxide particles are selected as fillers to improve the thermal stability and water resistance of the composite material. The high surface area of nano-silicon dioxide can provide more hydrophobic interfaces, increasing the number and effect of water resistance barriers. Micro-nano-sized nano-silicon dioxide particles can fill the micropores and defects in polyurethane, reducing the penetration channels of water molecules, and further improving the water resistance.

[0034] Boron nitride is selected to improve the thermal conductivity of polyurethane material, so that it is more efficient in heat transfer process, reduces the material temperature, and increases the stability.

[0035] The silane coupling agent can form a chemical bond on the surface of the filler, react with the matrix, thereby improving the compatibility of the filler and the matrix. The formation of such chemical bonds can enhance the adhesion between the filler and the matrix, reduce the interfacial tension between the filler and the matrix, thereby improving the strength, toughness and durability of the material. The silane coupling agent can form a protective film of organosilicon compounds on the surface of the filler, form a chemical bond with the matrix, and enhance the interfacial interaction between the filler and the matrix. This helps to improve the bonding strength, interfacial adhesion and interfacial energy transfer of the material, thereby improving the mechanical properties and durability of the material.

[0036] (Three) spraying equipment

[0037] Engineering applications or mass production can be carried out using spraying devices (such as Figure 2 ), the polyurethane A component and the B component with fillers are mixed, the material is loaded into the feeding port, heated to 60°C and stirred by an auger, the polyurethane A and B components are fully mixed and then sprayed out through a nozzle, the nozzle can be connected to a pipeline and a spray gun to extend the spraying distance to realize spraying of different environmental pole towers.

[0038] The present application is illustrated by the following examples, but the examples are only used for illustration and cannot be considered as limiting the scope or application method of the invention. Unless otherwise specified, the raw materials of the present application are commercially available. Among them, HDI (manufacturer: Shanghai Macklin Reagent Biochemical Technology Co., Ltd.), HTBN (manufacturer: Zibo Qilong Chemical Co., Ltd.), diol small molecule chain extender (ethylene glycol (EG) purity 99+% Acros Company, propylene glycol (PG) purity 98% Ark Company, 1,4-butanediol (BDO) purity 99+% Acros Company, 1,6-hexanediol (HDO) purity 98% Adamas Company). Aluminum oxide nanoparticles with a purity of 99.99% (manufacturer: Shanghai Macklin Reagent Biochemical Technology Co., Ltd., item number: A874824), hydrophobic fumed silica nanoparticles with a purity of 99.8% (manufacturer: Shanghai Macklin Reagent Biochemical Technology Co., Ltd., item number: N817578), high-purity boron nitride powder (particle size 13 microns, purity 99.99%, manufacturer: Nangong City Xindun Alloy Welding Material Spraying Co., Ltd.), silane coupling agent (Dow Corning, CAS: 23779-32-0, A-1160 ureidopropyl triethoxysilane).

[0039] In order to facilitate the testing of the performance of the polyurethane material prepared by the present application, test samples were prepared under laboratory conditions, as described in Example 1. Example 1

[0040] 50 parts by weight of HTBN were heated to 120°C in a four-necked flask and vacuum-dehydrated for 1 hour. The temperature was then lowered to 60°C, nitrogen gas was introduced, and 50 parts by weight of HDI were added. The mixture was reacted in a 60°C oil bath for 3 hours to obtain an isocyanate-terminated prepolymer (i.e., polyurethane component A). At 60°C, 100 parts by weight of a weighed diol small molecule chain extender (component B, composed of ethylene glycol:propylene glycol:1,4-butanediol:1,6-hexanediol in a mass ratio of 6:1.5:2:0.5) and a certain mass of functional filler (10 parts by weight of alumina nanoparticles, 1 part by weight of hydrophobic fumed silica nanoparticles, 5 parts by weight of high-purity boron nitride powder, and 10 parts by weight of silane coupling agent) were added directly to another flask. The mixture was stirred magnetically for 10 hours. After thorough stirring for minutes, the product is placed in an ultrasonic cleaner and strongly ultrasonically dispersed for 2 hours to depolymerize the filler agglomerates. Then, polyurethane component A and component B containing functional fillers are poured into a PTFE grinding disc and heated to 60°C in an oven for 2-3 hours for chain extension reaction. Afterward, a vacuum is applied using an oil pump for 12 hours to obtain solid polyurethane. The solid polyurethane is then demolded, heated to 120°C, and cured for 3 hours. Finally, it is hot-pressed into a film in a film press at 200°C to obtain the dielectric elastomer. SEM images and contact angle images are shown below. Figure 3 and Figure 4 As shown, Figure 3 The flake-like material consists of mixed boron nitride particles, while the smaller particles are nanofillers. Example 2

[0041] 50 parts by mass of HTBN were heated to 120°C in a four-necked flask and vacuum dehydrated for 1 hour. Then the temperature was lowered to 60°C, nitrogen gas was introduced, and 50 parts by mass of HDI were added. The mixture was reacted in an oil bath at 60°C for 3 hours to obtain an isocyanate-terminated prepolymer (i.e., polyurethane component A).

[0042] 26 parts by mass of functional filler (10 parts by mass of alumina nanoparticles, 1 part by mass of hydrophobic fumed silica nanoparticles, 5 parts by mass of high-purity boron nitride powder, and 10 parts by mass of silane coupling agent) were added to 100 parts by mass of component B (composed of ethylene glycol: propylene glycol: 1,4-butanediol: 1,6-hexanediol in a mass ratio of 6:1.5:2:0.5) and loaded into a spraying device together with 100 parts by mass of polyurethane component A. Figure 2 The material is heated to 60°C in the feed inlet and thoroughly mixed (by the auger) before being sprayed out through the nozzle and coated onto the tower surface. It is then naturally cured at room temperature for one week.

[0043] Compared with the insulating shield, the application uses an insulating spraying material without fixed shape, no visual clip and other power devices to cover the weak points such as insulator, wire clip, lightning arrester connection point and exposed point, which avoids the cost of production and installation of insulating shield caused by the difference in model. Compared with the similar RTV anti-pollution flashover coating, the electrical insulation performance of the spraying material is greatly improved, and it has a more extensive application scene. Compared with the similar spraying process of modified silicone rubber and modified epoxy resin, the modified polyurethane material has a shorter curing time and strong waterproof and corrosion-resistant performance, which is a good insulating armor material.

Claims

1. A method for producing a fast-curing material for insulating a tower side, characterized by, The method comprises the following steps: adding 26 parts by mass of functional fillers into 100 parts by mass of B component, loading the polyurethane A component into the feeding port of a spraying device, heating to 60 DEG C and mixing the materials, then spraying through a nozzle, coating on the surface of a substrate to be treated, and naturally curing at room temperature for one week to obtain a cured material; The polyurethane A component is prepared by heating a hydroxyl-terminated butadiene-acrylonitrile copolymer to 120 DEG C in a container, vacuum drying for 1 h, then cooling to 60 DEG C, introducing nitrogen, adding hexamethylene diisocyanate, and reacting at 60 DEG C for 3 h to obtain an isocyanate-terminated prepolymer, i.e., the polyurethane A component; The B component is a small-molecule diol chain extender composed of ethylene glycol, propylene glycol, 1,4-butanediol and 1,6-hexanediol in a mass ratio of 6:1.5:2:0.5; In the polyurethane A component, the number of moles of isocyanate groups of HDI is n, the number of moles of hydroxyl groups of HTBN is n1, and in the B component, the number of moles of hydroxyl groups of the small-molecule diol chain extender is n2, n=n1+n2; The functional fillers are composed of 10 parts by mass of aluminum oxide nanoparticles, 1 part by mass of hydrophobic fumed silica nanoparticles, 5 parts by mass of high-purity boron nitride powder and 10 parts by mass of silane coupling agent.

2. The fast-cured material for tower and pole side insulation prepared by the method of claim 1.

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