Two-component dual-curing submarine cable water-blocking pouring sealant as well as preparation method and application thereof

Abstract

The invention relates to a two-component dual-curing submarine cable water-blocking pouring sealant, which is composed of a component A and a component B according to a mass ratio of 1: 0.3-1, the component A comprises tricyclodecane modified hydroxyl-terminated polybutadiene, tertiary carbonate epoxy acrylate, polybutadiene, an acrylate-silicon dioxide nano composite material and a silane coupling agent, and the component B comprises a component C, a component D and a component E according to a mass ratio of 1: 0.3-1. A catalyst, a photoinitiator, an antioxidant, a defoaming agent and a polymerization inhibitor; the component B is prepared from an organic silicon modified dual-curing prepolymer, isocyanate and polybutadiene. The dual-component dual-curing submarine cable water-blocking pouring sealant can be subjected to UV and polyurethane dual curing, has excellent flowability and infiltration permeability, can be used for quickly and completely filling even a narrow gap, does not empty, does not generate a bubble defect, has high dual curing efficiency, and has relatively good water-blocking performance, electrical insulation performance and excellent high and low temperature resistance; long-term use reliability is stable, and submarine cables are effectively protected from seawater erosion.

Description

Technical Field

[0001] This invention relates to the field of submarine optical cable technology, specifically to a two-component, dual-curing water-blocking potting compound for submarine optical cables, its preparation method, and its application. Background Technology

[0002] With the nation's vigorous development of offshore wind power, the demand for high-voltage submarine cables has surged. Emerging technologies such as 5G, cloud computing, and data centers have also driven the growth in demand for submarine optical cables. Submarine optical cables transmit signals through a central optical fiber, and fiber optic attenuation is extremely sensitive to hydrogen. Furthermore, submarine optical cables with relays require high-voltage DC power. To ensure cable reliability, submarine optical cables must possess radial water-blocking capabilities. On the other hand, submarine optical cables may break during long-term operation due to human or natural factors, allowing seawater to enter the cable and spread longitudinally, damaging its information transmission capabilities. To prevent seawater from penetrating the entire cable and to minimize the length of cable scrapped during repairs, submarine cables must be able to withstand longitudinal seawater infiltration at specified water depths. As the application depth of submarine optical cables continues to increase, especially in trans-Pacific submarine optical cable systems, extremely stringent requirements are placed on the radial and longitudinal water-blocking performance of submarine optical cables. How to effectively prevent water intrusion and maintain the long-term stable operation of submarine optical cables has become an urgent technical challenge.

[0003] Currently, most water-blocking materials used in submarine cables on the market suffer from insufficient longitudinal water-blocking performance. Traditional water-blocking materials (such as ordinary water-blocking tape / powder) absorb water at only 1 / 30th the rate of fresh water in seawater environments and lack sufficient pressure resistance. Uneven filling in large-section conductors allows water to penetrate longitudinally along the gaps in the monofilaments. Commercially available hot melt adhesive systems and two-component adhesive systems used in fully filled processes are prone to forming air bubbles or voids when dealing with complex geometries or tiny gaps in submarine cable structures. These defects lead to a decrease in the cable's water-blocking performance. Poor control of the adhesive curing process, such as curing too quickly and insufficient time for the adhesive to penetrate, results in uneven adhesive application and voids. Slow curing of the adhesive can cause voids to flow during the static placement process after the cable is formed and wound, ultimately leading to a significant reduction or even loss of water-blocking performance. Moreover, these adhesives are prone to problems such as oil separation, hardening, and cracking due to poor bending resistance during cyclic testing from -60℃ to 85℃, leading to deterioration of material performance and affecting the long-term reliability of submarine cables. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a two-component, dual-curing water-blocking potting compound for submarine cables that addresses the shortcomings of the prior art. It can be cured by both UV and polyurethane, has good fluidity and wetting penetration, is not prone to voids and air bubbles during use, and has excellent water-blocking performance, protecting submarine cables from seawater corrosion.

[0005] The technical solution adopted by the present invention to solve the above-mentioned problems is as follows: A two-component, dual-curing water-blocking potting compound for submarine cables, comprising component A and component B in a mass ratio of 1:0.3 to 1:1; wherein component A, by weight parts, includes: 30-70 parts of tricyclodecane-modified hydroxyl-terminated polybutadiene, 10-30 parts of tertiary carbonate epoxy acrylate, 10-30 parts of polybutadiene, 10-20 parts of acrylate-silica nanocomposite material, 0.1-3 parts of silane coupling agent, 0.01-0.8 parts of catalyst, 0.1-4 parts of photoinitiator, 0.1-3 parts of antioxidant, 0.01-0.5 parts of defoamer, and 0.01-0.5 parts of polymerization inhibitor; component B, by weight parts, includes: 20-60 parts of organosilicon-modified dual-curing prepolymer, 20-50 parts of isocyanate, and 10-30 parts of polybutadiene.

[0006] In the above scheme, the structure of the tricyclodecane-modified hydroxyl-terminated polybutadiene is as follows: Formula 1; The degree of polymerization, n, is generally in the range of 15 to 30. .

[0007] In the above scheme, the molecular structure of the tertiary carbonate epoxy acrylate is as follows: .

[0008] This tertiary carbonate epoxy acrylate possesses both hydroxyl and acrylate double bonds in its molecular chain, exhibiting dual curing activity. Furthermore, the tertiary carbon groups provide significant steric hindrance, protecting the ester bonds of the tertiary carbonate from decomposition and also hindering the decomposition of adjacent, easily decomposed groups in the polymer. This significantly improves its chemical resistance, weather resistance, and water-blocking properties. Additionally, the large volumetric structure of the tertiary carbon groups reduces intermolecular forces (such as chain entanglement) within the potting compound system, thereby drastically reducing the system viscosity.

[0009] In the above scheme, the preparation method of the tertiary carbonate epoxy acrylate is as follows: 1 mol of tertiary carbonate glycidyl ester, ammonium salt catalyst benzyltriethylammonium chloride (the amount of the catalyst added is 0.3% of the mass of tertiary carbonate glycidyl ester), and polymerization inhibitor p-hydroxyanisole (the amount of the polymerization inhibitor added is 0.5% of the mass of tertiary carbonate glycidyl ester) are stirred and mixed evenly, heated to 100~110℃ and stirred at a constant temperature, 1 mol of acrylic acid is added dropwise, and the dropwise addition time is controlled at 1~2h; after the dropwise addition is completed, the reaction temperature is controlled at 100~110℃, and the reaction is refluxed for 3~4h to obtain tertiary carbonate epoxy acrylate.

[0010] The structure of the tert-butyl glycidyl carbonate is as follows: ; The structure of the acrylic acid is as follows: .

[0011] In the above scheme, the polybutadiene is a low-vinyl content polybutadiene with a vinyl content of 20-35 wt% and a molecular weight of around 2500. It has a relatively low viscosity and a structure similar to that of the polybutadiene in the two-component adhesive matrix (i.e., tricyclodecane-modified hydroxyl-terminated polybutadiene and silicone-modified dual-curable prepolymer). Therefore, it exhibits good compatibility and dilution effect with the two-component dual-curing submarine cable water-blocking potting compound system of the present invention, maintaining its viscosity within a low range. Furthermore, the double bonds on the polybutadiene molecular chain can participate in the UV curing of the two-component dual-curing submarine cable water-blocking potting compound system, increasing the strength of the cured adhesive. This low-vinyl content polybutadiene has excellent low-temperature resistance, and its application in the two-component dual-curing submarine cable water-blocking potting compound system of the present invention can further improve the low-temperature resistance of the potting compound. Specifically, the polybutadiene is preferably Clayville liquid polybutadiene Ricon 130.

[0012] In the above scheme, the acrylate-silica nanocomposite material is one or more of 601A-35, 601C-35, and 601Q-35 from Changxing Chemical Materials Co., Ltd., mixed in any proportion. These acrylate-silica nanocomposite materials are silica / acrylate hybrid resins synthesized by the sol-gel method. Inorganic silica nanoparticles (with a particle size of about 10-20 nm) are uniformly dispersed in the acrylate polymer network, forming a relatively dense water-blocking barrier, which can further improve the water-blocking performance of the potting compound. In addition, the addition of the acrylate-silica nanocomposite material to the potting compound of the present invention can effectively reduce the curing shrinkage rate of the system and improve the tensile, flexural and impact strength.

[0013] In the above scheme, the catalyst in component A is selected from one or more of stannous octoate, dibutyltin dilaurate, organic bismuth catalysts (such as Vantrus Coscat® 83) in any proportion.

[0014] In the above scheme, the photoinitiator is selected from one or more of ethyl 2,4,6-trimethylbenzoylphenylphosphonate (TPO-L), bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide (819), 2,4,6-trimethylbenzoyl-di(p-tolyl)phosphine oxide (TMO) in any proportion.

[0015] In the above scheme, the antioxidant is a macromolecular active antioxidant, 2-(2-hydroxy-3-tert-butyl-5-methylbenzyl)-4-methyl-6-tert-butylphenyl acrylate (GM). It is a hindered phenol-acrylate composite antioxidant with both free radical scavenging and peroxide decomposition functions, effectively preventing polymer thermal aging. Because this macromolecular active antioxidant contains acrylate functional groups, it can participate in the radiation crosslinking and curing of the potting compound without migrating, ensuring the long-term reliability of the two-component submarine cable water-blocking potting compound.

[0016] In the above scheme, the defoamer is one or more of TEG RAD 2500, TEG RAD 2600, TEG RAD 2650, and TEG RAD2700, mixed in any proportion. These defoamers have the characteristics of accelerating defoaming and defoaming, which can quickly eliminate air bubbles in the two-component submarine cable water-blocking potting compound, preventing water leakage and scrapping of the submarine cable due to voids caused by air bubbles during the production and rapid coating process. Unlike other defoamers, because it contains acrylate functional groups, it can participate in the radiation crosslinking and curing of the potting compound, reducing the release of small molecule substances in the system.

[0017] In the above scheme, the polymerization inhibitor is p-hydroxyanisole, which is a highly efficient polymerization inhibitor used to inhibit the premature polymerization reaction of double bonds in acrylate and butadiene, improve the storage stability of component A, and extend the shelf life of the two-component water-blocking adhesive.

[0018] In the above scheme, the molecular structure of the organosilicon-modified dual-curable prepolymer is as follows: Formula 3 The degree of polymerization n is generally in the range of 15 to 30, and the degree of polymerization m is generally in the range of 1 to 5. , .

[0019] The isocyanate groups at both ends of the molecular chain of the aforementioned silicone-modified dual-curable prepolymer provide the reactivity of polyurethane, reacting with the hydroxyl groups in component A to extend and crosslink the molecular chain. Simultaneously, the double bonds in the polybutadiene molecular chain can participate in free radical photocuring to further increase the crosslinking density, ultimately forming a three-dimensional network structure. The main polybutadiene structure of the molecular chain has strong hydrophobicity, while the middle structure is composed of silicone segments. The Si-O bond energy (450 kJ / mol) in the silicone polymer is much greater than the C-C bond energy (345 kJ / mol) and C-O bond energy (351 kJ / mol), exhibiting advantages such as good thermal stability, oxidation resistance, and weather resistance. Introducing silicone segments into this dual-curable prepolymer, while maintaining advantages such as strong adhesion and good corrosion resistance, can reduce the internal stress of the cured product, increase toughness and heat resistance, and also enhance the wetting and leveling properties of the water-blocking potting compound, giving it rapid leveling and penetration performance.

[0020] In the above scheme, the isocyanate is one or more of 4,4'-dicyclohexylmethane diisocyanate (HMDI), diphenylmethane diisocyanate (MDI), Yantai Wanhua WANNATE HT-400, etc., in any proportion.

[0021] The preparation method of the two-component, dual-curing submarine cable water-blocking potting compound of the present invention includes the following steps: (1) According to the components and their weight parts of component A, tricyclodecane modified hydroxyl-terminated polybutadiene and polybutadiene are heated to 102±2℃ and vacuum dehydrated for 2-4 hours. Then, the material temperature is reduced to 60±2℃, and tertiary carbonate epoxy acrylate, acrylate-silica nanocomposite material, silane coupling agent, catalyst, photoinitiator, antioxidant, defoamer, and polymerization inhibitor are added in sequence. The mixture is stirred in the dark and kept warm for 1-2 hours. After stirring, it is filtered and defoamed to obtain component A. (2) According to the components and their weight parts of component B, heat the polybutadiene to 102±2℃ and dehydrate it under vacuum for 2-4 hours. Then, lower the material temperature to room temperature and add the organosilicon-modified dual-curable prepolymer and isocyanate in sequence. Keep the mixture at room temperature and stir for 1-2 hours. After stirring, filter and degas to obtain component B. (3) Mix components A and B at a mass ratio of 1:0.3 to 1:1 and stir evenly to obtain the two-component dual-curing submarine cable water-blocking potting compound.

[0022] The two-component, dual-curing water-blocking potting compound for submarine cables of the present invention has a viscosity (25°C) of 200~800 mPa.s, a hardness (SHORE OO) of 30~90H after curing, an elongation at break of >60%, a Tg of <-50°C, a water absorption rate of <0.5%, a curing shrinkage rate of <3%, and a change in hardness upon heating (500hrs, 70°C) of <5H; preferably, the viscosity (25°C) is 200~600 mPa.s, the hardness (SHORE OO) after curing is 50~80H, the elongation at break is >90%, the Tg of <-60°C, the water absorption rate of <0.1%, the curing shrinkage rate of <2%, and the change in hardness upon heating (500hrs, 100°C) of <3H.

[0023] Based on the above, the present invention also provides a submarine cable using the two-component dual-curing submarine cable water-blocking potting compound described in the present invention. The preparation method is as follows: First, a stainless steel tube is continuously and seamlessly welded to the outside of the optical fiber by laser welding. The stainless steel tube is filled with hydrogen-absorbing fiber paste. Three types of inner armored steel wires of different diameters are stranded on the outside of the stainless steel tube. When the steel wires are stranded, the two-component dual-curing submarine cable water-blocking potting compound is applied / poured into the stranded steel wires and the gaps between the steel wires by dispensing / pouring equipment. UV pre-curing is performed by UV curing equipment for rapid shaping. Copper strips are drawn into copper tubes after being welded by three guns argon arc welding on the outside of the steel wire layers. The bonding layer and insulation layer are extruded on the outside of the copper tube by a twin-screw long-time serial extrusion process. After extrusion molding, cooling and winding are performed. During the storage and placement of the cable, the water-blocking compound filled inside the submarine cable undergoes secondary polyurethane curing to finally form the final shape, thus obtaining a submarine optical cable with excellent water-blocking performance.

[0024] Compared with the prior art, the beneficial effects of the present invention are: First, the two-component, dual-curing submarine cable water-blocking potting compound of the present invention has low viscosity, good fluidity, and good wetting and penetration, which can fill even narrow gaps well without empty glue or air bubble defects. Secondly, the curing speed of the two-component dual-curing submarine cable water-blocking potting compound described in this invention is controllable. After the submarine cable is filled with the potting compound, it is first quickly cured and shaped by a UV curing device (quick initial curing without dripping), which facilitates the efficient and rapid production and winding of the submarine cable. During subsequent storage and placement, the isocyanate groups and hydroxyl groups on the prepolymer molecular chain of the adhesive undergo further polyurethane-enhanced curing to form a relatively dense three-dimensional polymer network structure, which better blocks the penetration and passage of water molecules, achieving excellent water-blocking performance. Third, the two-component, dual-curing submarine cable water-blocking potting compound of the present invention has good electrical insulation properties and excellent high and low temperature resistance, and its long-term reliability is stable, protecting the submarine cable from seawater corrosion.

[0025] Fourth, the two-component, dual-curing submarine cable water-blocking potting compound of the present invention has good transparency and moderate strength. It can ensure that the submarine cable has good water-blocking performance, and can also quickly distinguish the cable structure and cleanly remove the adhesive from the repaired part during the construction and maintenance of the submarine cable, which can greatly improve the construction efficiency.

[0026] Fifth, the two-component, dual-curing submarine cable water-blocking potting and curing colloid of the present invention has no VOC emissions, low odor, complies with the latest EU REACH regulations, will not cause harm to the health of production personnel, and is very safe and environmentally friendly. Attached Figure Description

[0027] Figure 1 The reaction equation for preparing tricyclodecane-modified hydroxyl-terminated polybutadiene.

[0028] Figure 2 The reaction equation for preparing tertiary carbonate epoxy acrylate.

[0029] Figure 3 The reaction equation for preparing organosilicon-modified dual-curable prepolymers.

[0030] Figure 4 This is a schematic diagram of the transverse cross-section of a certain type of submarine optical cable. In the diagram: 1. Optical fiber, 2. Hydrogen-absorbing fiber paste, 3. Adhesive layer, 4. Insulation layer, 5. Copper tube, 6. Water-blocking adhesive, 7. Steel wire layer, 8. Stainless steel tube. Detailed Implementation

[0031] To better understand the present invention, the following embodiments further illustrate the content of the present invention, but the present invention is not limited to the following embodiments.

[0032] The tricyclodecane-modified hydroxyl-terminated polybutadiene structure used in the following examples is shown below:

[0033] Wherein, the degree of polymerization n = 21~22, Its preparation method is as follows: 1 mol of tricyclodecanediethanol and 2 mol of isophthalic dimethyl isocyanate (XDI) were heated and stirred. Dibutyltin dilaurate (0.05% of the total mass of tricyclodecanediethanol and isophthalic dimethyl isocyanate) was added as a catalyst, and the mixture was heated to 40-45°C and reacted for 2-3 hours. After the reaction was complete, 2 mol of hydroxyl-terminated polybutadiene polyol, 0.05% of the hydroxyl-terminated polybutadiene polyol catalyst, and p-hydroxyanisole (0.1% of the hydroxyl-terminated polybutadiene polyol polymerization inhibitor) were added. The mixture was then heated to 70-75°C and reacted for 3-4 hours to obtain tricyclodecane-modified hydroxyl-terminated polybutadiene. The reaction equations involved are as follows: Figure 1 As shown.

[0034] The structure of the tricyclodecanediethanol is as follows: ; The structure of the m-phenylenedimethyl isocyanate (XDI) is as follows: ; The hydroxyl-terminated polybutadiene polyol used is Krevili PolyBD R45V, with a molecular weight of approximately 2800 and a hydroxyl content of 0.85 mmol / g. Its molecular structure is as follows: n is approximately 21 to 22.

[0035] In the preparation of tricyclodecane-modified hydroxyl-terminated polybutadiene, isophthalic dimethyl isocyanate (XDI) is used to extend the chain of tricyclodecanediethanol and hydroxyl-terminated polybutadiene. This not only provides the molecular chain with more benzene ring structures, further blocking the passage and penetration of water molecules, but also, due to the high reactivity and high production efficiency of isophthalic dimethyl isocyanate, the synthesized product has a lower viscosity. The resulting tricyclodecane-modified hydroxyl-terminated polybutadiene, with its three-membered ring structure of tricyclodecane in the molecular chain, endows the polymer with good adhesion, high tensile strength, heat resistance, weather resistance, and impact resistance. The hydroxyl groups at both ends of the molecular chain provide the reactivity of polyurethane, which can react with the isocyanate groups in component B, playing a role in chain extension and cross-linking. At the same time, the double bonds in the polybutadiene molecular chain can also participate in free radical photocuring to further increase the cross-linking density, ultimately forming a three-dimensional network structure.

[0036] In the following examples, the structure of the tertiary carbonate epoxy acrylate is as follows: The specific preparation steps are as follows: 1 mol of glycidyl tert-carbonate, benzyl triethylammonium chloride catalyst (catalyst amount is 0.3% of the total mass of glycidyl tert-carbonate and acrylic acid), and p-hydroxyanisole polymerization inhibitor (polymerization inhibitor amount is 0.5% of the total mass of glycidyl tert-carbonate and acrylic acid) are heated and stirred until homogeneous. When the temperature rises to 100~110℃, 1 mol of acrylic acid is added dropwise at a uniform rate, with the addition time controlled at 1~2 hours. After the addition is completed, the reaction temperature is controlled at 100~110℃, and the reaction is refluxed for 3~4 hours to obtain tert-carbonate epoxy acrylate. The reaction equations involved are as follows: Figure 2 As shown.

[0037] The structure of the tert-butyl glycidyl carbonate is as follows:

[0038] The structure of the acrylic acid is as follows: . In the following examples, the structure of the silicone-modified dual-curable prepolymer used is as follows:

[0039] Wherein, the degree of polymerization m = 2~3, n = 21~22, , Its preparation method is as follows: 1 mol of hydroxyl silicone oil (10% hydroxyl content) and 2 mol of isophthalic dimethyl isocyanate (XDI) were heated and stirred. Dibutyltin dilaurate catalyst (0.05% of the total mass of hydroxyl silicone oil and isophthalic diisocyanate) was added, and the mixture was then heated to 40-45°C and reacted at this temperature for 2-3 hours. Then, 2 mol of hydroxyl-terminated polybutadiene polyol and 0.05% of the mass of hydroxyl-terminated polybutadiene polyol catalyst were added. The reaction mixture is prepared by adding p-hydroxyanisole (0.1% of the mass of the hydroxyl-terminated polybutadiene polyol) and a polymerization inhibitor, p-hydroxyanisole (at a concentration of 0.1% of the mass of the hydroxyl-terminated polybutadiene polyol), heating to 70-75°C and reacting at this temperature for 3-4 hours. Then, 2 mol of isophthalic acid diisocyanate and dibutyltin dilaurate (0.05% of the mass of the isophthalic acid diisocyanate) are added, and the reaction is continued at 70-75°C for another 3-4 hours to obtain the organosilicon-modified dual-curable prepolymer. The reaction equations involved are as follows: Figure 3 As shown.

[0040] The hydroxyl silicone oil was purchased from Jiangsu Keqi Polymer Materials Co., Ltd., with the product name OH-003, a viscosity of 20~30 cst, and a hydroxyl content of 10%. Its specific structure is as follows: The degree of polymerization m is approximately 2 to 3; The structure of the m-phenylenedimethyl isocyanate (XDI) is as follows: ; The structure of the hydroxyl-terminated polybutadiene polyol is as follows: , n=21~22.

[0041] In the following embodiments, the structure of the photoinitiator ethyl 2,4,6-trimethylbenzoylphenylphosphonate (TPO-L) is as follows: ; The structure of the photoinitiator (2,4,6-trimethylbenzoyl)phosphine di(p-tolyl)oxide (TMO) is as follows: ; The structure of the photoinitiator phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide is as follows: .

[0042] In the following examples, the polybutadiene is a low-vinyl content polybutadiene with a vinyl content of 20-35 wt% and a molecular weight of 2500.

[0043] Example 1 A two-component, dual-curing water-blocking potting compound for submarine cables, comprising component A and component B in a mass ratio of 1:0.3; wherein component A comprises, by weight, the following components: 40 parts of tricyclodecane-modified hydroxyl-terminated polybutadiene, 16 parts of tert-carbonate epoxy acrylate, 25 parts of polybutadiene, 13.8 parts of acrylate-silica nanocomposite material (601A-35 from Changxing Chemical Materials Co., Ltd.), 1.2 parts of silane coupling agent KH570, 0.3 parts of catalyst, 2 parts of photoinitiator, 1 part of antioxidant 2-(2-hydroxy-3-tert-butyl-5-methylbenzyl)-4-methyl-6-tert-butylphenyl acrylate (GM), 0.3 parts of defoamer, and 0.4 parts of polymerization inhibitor p-hydroxyanisole; component B comprises, by weight, the following components: 35 parts of organosilicon-modified dual-curing prepolymer, 45 parts of isocyanate, and 20 parts of polybutadiene.

[0044] The catalyst comprises, by weight percentage: 50% stannous octoate and 50% dibutyltin dilaurate; the photoinitiator comprises, by weight percentage: 40% ethyl 2,4,6-trimethylbenzoylphenylphosphonate (TPO-L) and 60% (2,4,6-trimethylbenzoyl)bis(p-tolyl)phosphine oxide (TMO); the defoamer comprises, by weight percentage: 25% Evonik Specialty Chemicals TEG RAD 2500 and 75% Evonik Specialty Chemicals TEG RAD 2650; and the isocyanate comprises, by weight percentage: 50% HMDI and 50% WANNATE HT-400.

[0045] Example 2 A two-component, dual-curing water-blocking potting compound for submarine cables, comprising component A and component B in a 1:1 mass ratio; wherein component A comprises, by weight, the following components: 50 parts of tricyclodecane-modified hydroxyl-terminated polybutadiene, 20 parts of tert-carbonate epoxy acrylate, 11 parts of polybutadiene, 15 parts of acrylate-silica nanocomposite material (601C-35 from Changxing Chemical Materials Co., Ltd.), 1.3 parts of silane coupling agent KH570, 0.13 parts of catalyst, 1 part of photoinitiator, 1.2 parts of antioxidant 2-(2-hydroxy-3-tert-butyl-5-methylbenzyl)-4-methyl-6-tert-butylphenyl acrylate (GM), 0.23 parts of defoamer, and 0.14 parts of polymerization inhibitor p-hydroxyanisole; component B comprises, by weight, the following components: 62 parts of organosilicon-modified dual-curing prepolymer, 20 parts of isocyanate, and 18 parts of polybutadiene.

[0046] The catalyst comprises, by weight percentage: 40% of Vantrus organic bismuth catalyst Coscat® 83 and 60% of dibutyltin dilaurate; the photoinitiator comprises, by weight percentage: 60% of ethyl 2,4,6-trimethylbenzoylphenylphosphonate (TPO-L) and 40% of phenyl bis(2,4,6-trimethylbenzoyl)phosphine oxide; the defoamer comprises, by weight percentage: 50% of Evonik Specialty Chemicals TEG RAD 2600 and 50% of Evonik Specialty Chemicals TEG RAD 2700; and the isocyanate comprises, by weight percentage: 60% of HMDI and 40% of MDI.

[0047] Example 3 A two-component, dual-curing water-blocking potting compound for submarine cables, comprising component A and component B in a mass ratio of 1:0.5; wherein component A comprises, by weight, the following components: 35 parts of tricyclodecane-modified hydroxyl-terminated polybutadiene, 20 parts of tert-carbonate epoxy acrylate, 22 parts of polybutadiene, 16 parts of acrylate-silica nanocomposite material (601Q-35 from Changxing Chemical Materials Co., Ltd.), 2.0 parts of silane coupling agent KH570, 0.1 parts of catalyst, 3.1 parts of photoinitiator, 1.5 parts of antioxidant 2-(2-hydroxy-3-tert-butyl-5-methylbenzyl)-4-methyl-6-tert-butylphenyl acrylate (GM), 0.21 parts of defoamer TEG RAD 2650, and 0.09 parts of polymerization inhibitor p-hydroxyanisole; component B comprises, by weight, the following components: 46 parts of organosilicon-modified dual-curing prepolymer, 32 parts of isocyanate, and 22 parts of polybutadiene.

[0048] The catalyst comprises, by weight percentage: 20% of Vantrus organic bismuth catalyst Coscat® 83 and 80% of stannous octoate; the photoinitiator comprises, by weight percentage: 90% of (2,4,6-trimethylbenzoyl)phosphine bis(p-tolyl)oxide (TMO) and 10% of phenylbis(2,4,6-trimethylbenzoyl)oxide; the isocyanate comprises, by weight percentage: 80% MDI and 20% of Yantai Wanhua WANNATE HT-400.

[0049] Example 4 A two-component, dual-curing water-blocking potting compound for submarine cables, comprising component A and component B in a mass ratio of 1:0.6; wherein component A comprises the following components by weight: 30 parts of tricyclodecane-modified hydroxyl-terminated polybutadiene, 24 parts of tert-carbonate epoxy acrylate, 22 parts of polybutadiene, 19 parts of acrylate-silica nanocomposite material (Changxing Chemical Materials Co., Ltd.'s 601A-35), 1.5 parts of silane coupling agent KH570, 0.12 parts of catalyst, 1.9 parts of photoinitiator, 1.23 parts of antioxidant 2-(2-hydroxy-3-tert-butyl-5-methylbenzyl)-4-methyl-6-tert-butylphenyl acrylate (GM), and defoamer TEG RAD2650. 0.15 parts, polymerization inhibitor p-hydroxyanisole 0.10 parts; Component B includes the following components by weight: 50 parts of silicone-modified dual-curable prepolymer, 30 parts of isocyanate, and 20 parts of polybutadiene.

[0050] The catalyst comprises, by weight percentage: 10% of Vantrus organic bismuth catalyst Coscat® 83 and 90% of dibutyltin dilaurate; the photoinitiator comprises, by weight percentage: 80% of (2,4,6-trimethylbenzoyl)bis(p-tolyl)phosphine oxide (TMO) and 20% of ethyl 2,4,6-trimethylbenzoylphenylphosphonate (TPO-L); the isocyanate comprises, by weight percentage: 80% MDI and 20% HMDI.

[0051] The preparation method of the two-component, dual-curing submarine cable water-blocking potting compound in Examples 1-4 includes the following specific steps: (1) According to the components and dosage of component A in the above embodiments, tricyclodecane modified hydroxyl-terminated polybutadiene and polybutadiene are heated to 102±2℃ and vacuum dehydrated for 3h. Then the material temperature is reduced to 60±2℃, and tertiary carbonate epoxy acrylate, acrylate-silica nanocomposite material, silane coupling agent, catalyst, photoinitiator, antioxidant, defoamer and polymerization inhibitor are added in sequence. The mixture is stirred in the dark and kept warm for 1.5 hours. After stirring, it is filtered and defoamed to obtain component A. (2) According to the components and dosage of component B in the above embodiments, the polybutadiene was heated to 102±2℃ and vacuum dehydrated for 3h. Then the material temperature was reduced to room temperature, and the organosilicon-modified dual-curable prepolymer and isocyanate were added in sequence. The mixture was stirred at room temperature for 1.5 hours. After stirring, the mixture was filtered and degassed to obtain component B. (3) When using, weigh and mix components A and B according to the mass ratio in each embodiment and stir evenly to obtain the finished two-component dual-curing submarine cable water-blocking potting compound of each embodiment.

[0052] The performance of the two-component, dual-curing submarine cable water-blocking potting compounds prepared in Examples 1-4 was tested, and the results are shown in Table 1. A commercially available two-component polyurethane potting compound was used as a comparative example.

[0053] Table 1 Technical specifications of Examples 1-4 and comparative examples.

[0054] As shown in Table 1, the viscosity (25℃) of the prepared adhesive in the examples is in the range of 250~600 mPa·s, which is low and has good fluidity, making it easy to fill and effectively avoiding defects such as voids and bubbles. The hardness (SHORE OO) after curing is between 55~80H, which ensures that it has a certain strength during use and is easy to remove during maintenance. The elongation at break is between 105%~140%, which ensures that the cured adhesive has good flexibility and good bending resistance. Tg < -60℃ ensures that the cured adhesive has excellent low-temperature performance. The water absorption rate ≤0.06% ensures that the cured adhesive has good water-blocking effect. The curing shrinkage rate <1% reduces the internal stress of the adhesive during the curing process, and the volume change before and after curing is small, preventing voids and maintaining good adhesion. The change in hardness after heating (500hrs, 70℃) ≤2H ensures the long-term reliability and stability of the adhesive.

[0055] Application examples To verify the water-blocking performance of submarine optical cables produced by the two-component, dual-curing water-blocking potting compound described in this invention, submarine optical cables were fabricated using the potting compounds prepared in each embodiment according to the following method, with a commercially available two-component potting compound used as a comparative example. Specific conditions and methods are as follows: Preparation such as Figure 4 The submarine optical cable with the structure shown is first made by laser welding a continuous, seamless stainless steel tube to the outside of the optical fiber. The stainless steel tube is filled with hydrogen-absorbing fiber paste. Three types of inner armored steel wires of different diameters are twisted together on the outside of the stainless steel tube. When the steel wires are twisted together, the two-component, double-curing submarine cable water-blocking potting compound is applied / poured into the stranded steel wires and the gaps between the steel wires using a dispensing / pouring equipment. UV pre-curing is performed for rapid shaping using a UV curing equipment. Copper strips are drawn into copper tubes after being welded by three guns in an argon arc. The bonding layer and insulation layer are extruded on the outside of the copper tube using a twin-screw long-time serial extrusion process. After extrusion molding, the cable is cooled and wound up. During the cable storage and placement process, the water-blocking adhesive filled inside the submarine cable undergoes a second curing of polyurethane to finally form the final shape, thus obtaining a submarine optical cable with excellent water-blocking performance and stable long-term reliability.

[0056] A 500m sample of the above-mentioned submarine optical cable was subjected to a 5MPa hydrostatic pressure test for 14 consecutive days. The longitudinal seepage length of the submarine cable after the test is shown in Table 2. The longitudinal seepage length of the submarine cable prepared by the potting compound of the present invention is in the range of 33~53m, and the test results are qualified, which is significantly lower than the longitudinal seepage length of 165m of the control group.

[0057] Table 2 Water seepage test results for submarine optical cable samples

[0058] The above description is only a preferred embodiment of the present invention. It should be noted that those skilled in the art can make several improvements and modifications without departing from the inventive concept of the present invention, and these all fall within the protection scope of the present invention.

Claims

1. A two-component dual-cure water-blocking pouring sealant for submarine cables, characterized in that, The A component and the B component are composed according to the mass ratio of 1:0.3-1:1, wherein the A component comprises, in parts by weight: tricyclodecane modified hydroxyl-terminated polybutadiene 30-70 parts, tertiary carbonate epoxy acrylate 10-30 parts, polybutadiene 10-30 parts, acrylate-silicon dioxide nanocomposite 10-20 parts, silane coupling agent 0.1-3 parts, catalyst 0.01-0.8 parts, photoinitiator 0.1-4 parts, antioxidant 0.1-3 parts, defoaming agent 0.01-0.5 parts, and polymerization inhibitor 0.01-0.5 parts; and the B component comprises, in parts by weight: organosilicon modified dual-curable prepolymer 20-60 parts, isocyanate 20-50 parts, and polybutadiene 10-30 parts.

2. The dual-component dual-cure water-blocking pouring sealant for submarine cables according to claim 1, characterized in that, The tricyclodecane modified hydroxyl-terminated polybutadiene has a structure as shown in Formula 1: Formula 1; wherein .

3. The dual component dual cure water blocking potting adhesive for submarine cable according to claim 1, characterized in that, The preparation method of the tricyclodecane modified hydroxyl-terminated polybutadiene comprises the following steps: heating and stirring tricyclodecanedimethyl alcohol and m-xylyl isocyanate, adding a catalyst dibutyltin dilaurate, then increasing the temperature to 40-45 DEG C for constant temperature reaction for 2-3 hours; after the reaction is completed, adding hydroxyl-terminated polybutadiene polyol, catalyst dibutyltin dilaurate and polymerization inhibitor p-hydroxyanisole, increasing the temperature to 70-75 DEG C for constant temperature reaction for 3-4 hours, and obtaining the tricyclodecane modified hydroxyl-terminated polybutadiene.

4. The dual component dual cure water blocking potting adhesive for submarine cable according to claim 1, characterized in that, The tertiary carbonate epoxy acrylate has a structure as shown in Formula 2: Formula 2.

5. The dual component dual cure water blocking potting gel for submarine cable according to claim 1, characterized in that, The preparation method of the tertiary carbonate epoxy acrylate comprises the following steps: uniformly stirring glycidyl ester carbonate, ammonium salt catalyst and polymerization inhibitor p-hydroxyanisole, increasing the temperature to 100-110 DEG C for constant temperature stirring, dropwise adding acrylic acid, controlling the dropwise adding time in 1-2 hours; controlling the reaction temperature at 100-110 DEG C after the dropwise adding is completed, refluxing for 3-4 hours, and obtaining the tertiary carbonate epoxy acrylate.

6. The dual component dual cure water blocking potting gel for submarine cables according to claim 1, characterized in that, The polybutadiene has a vinyl content of 20-35 wt%, and a molecular weight of 2000-3000.

7. The dual component dual cure water blocking potting gel for submarine cable according to claim 1, characterized in that The catalyst is selected from one or more of stannous octoate, dibutyltin dilaurate and organic bismuth catalyst in an arbitrary ratio; and the photoinitiator is selected from one or more of 2,4,6-trimethylbenzoyl phenyl phosphinic acid ethyl ester, bis(2,4,6-trimethylbenzoyl) phenyl phosphine oxide and 2,4,6-trimethylbenzoyl-di(p-tolyl) phosphine oxide in an arbitrary ratio.

8. The dual component dual cure water blocking potting gel for submarine cable according to claim 1, characterized in that The antioxidant is macromolecular active antioxidant 2-(2-hydroxy-3-tert-butyl-5-methylbenzyl)-4-methyl-6-tert-butyl phenyl acrylate; the defoaming agent is one or more of TEG RAD 2500, TEG RAD 2600, TEG RAD 2650 and TEG RAD 2700 in an arbitrary ratio; and the polymerization inhibitor is p-hydroxyanisole.

9. The dual component dual cure water blocking potting gel for submarine cable according to claim 1, characterized in that, The organosilicon modified dual-curable prepolymer has a structure as shown in Formula 3: Formula 3 wherein , .

10. The dual component dual cure water blocking potting gel for submarine cables according to claim 1, characterized in that, The preparation method of the organic silicon modified dual-curable prepolymer is as follows: the hydroxyl silicone oil and m-xylyl isocyanate are heated and stirred, a catalyst dibutyltin dilaurate is added, then the temperature is increased to 40-45 DEG C and kept constant for 2-3 hours, then the hydroxyl-terminated polybutadiene polyol, the catalyst dibutyltin dilaurate and the polymerization inhibitor p-hydroxyanisole are added, the temperature is increased to 70-75 DEG C and kept constant for 3-4 hours, then the m-xylyl isocyanate and the catalyst dibutyltin dilaurate are added, and the temperature is kept constant at 70-75 DEG C for 3-4 hours, to obtain the organic silicon modified dual-curable prepolymer.

11. The method for preparing a two-component dual-curing water-blocking pouring sealant for submarine cables according to claim 1, characterized in that, Comprising the following steps: (1) according to the components and the weight percentage of each component in claim 1, the tricyclodecane modified hydroxyl-terminated polybutadiene and polybutadiene are heated to 100-105 DEG C and vacuum dewatered for 2-4 hours, then the material temperature is reduced to 58-62 DEG C, the tertiary carbonate epoxy acrylate, the acrylate-silica nanocomposite, the silane coupling agent, the catalyst, the photoinitiator, the antioxidant, the defoaming agent and the polymerization inhibitor are added in sequence, and the mixture is stirred for 1-2 hours in dark, then filtered and defoamed, to obtain the A component; (2) according to the components and the weight percentage of each component in claim 1, the polybutadiene is heated to 100-105 DEG C and vacuum dewatered for 2-4 hours, then the material temperature is reduced to room temperature, the organic silicon modified dual-curable prepolymer and the isocyanate are added in sequence, and the mixture is stirred for 1-2 hours at room temperature, then filtered and defoamed, to obtain the B component; (3) when used, the A and B components are mixed in a mass ratio of 1:0.3-1:1, and uniformly stirred, to obtain the two-component dual-curable submarine cable water-blocking pouring sealant.

12. A submarine optical cable, characterized by The submarine optical cable prepared by using the two-component dual-curable submarine cable water-blocking pouring sealant in any one of claims 1-14.

13. A method of manufacturing a submarine optical cable, characterized by, Comprising the following steps: (1) a stainless steel pipe is welded outside the optical fiber, then twisted by steel wires, and the two-component dual-curable submarine cable water-blocking pouring sealant in any one of claims 1-14 is spot-coated or poured into the gap between the layer-twisted steel wires and the steel wires during the steel wire twisting process, and then pre-cured by ultraviolet light to shape; (2) after the copper pipe and the adhesive layer and the insulation layer are sequentially arranged outside the steel wire layer, the submarine cable water-blocking pouring sealant is cured again to shape by polyurethane, to obtain the submarine optical cable with excellent water-blocking performance.

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