Fiber reinforced resin composite core for overhead conductor and preparation method of fiber reinforced resin composite core

Abstract

The invention provides a fiber reinforced resin composite core for an overhead conductor, the fiber reinforced resin composite core is prepared by compounding components including reinforced fibers and thermoplastic resin, and the reinforced fibers are selected from one or more of carbon fibers, glass fibers, basalt fibers and alumina fibers; the thermoplastic resin is prepared from a prepolymer, a chain extender and a catalyst; the invention also provides a preparation method of the fiber reinforced resin composite core for the overhead conductor. According to the fiber reinforced resin composite core for the overhead conductor, thermoplastic resin is adopted to replace thermosetting resin in the prior art, so that the forming speed is increased, the generation efficiency of the composite core is improved, and meanwhile, the recovery rate and the utilization rate of materials are improved; and stable and rapid preparation of the fiber-reinforced thermoplastic composite core is realized.

Description

Technical Field

[0001] The present invention relates to the technical field of overhead conductors, and particularly to a fiber-reinforced resin composite core for overhead conductors and a preparation method thereof. Background Art

[0002] Carbon fiber-reinforced resin composite cores, due to the advantages of high strength and low linear expansion coefficient of the carbon fiber itself, are used as the strengthening cores of overhead conductors to make composite core conductors. Compared with traditional steel core-reinforced overhead conductors, they have significant advantages such as high temperature resistance, large capacity, low sag, low energy consumption, and light weight, becoming a disruptive product in the field of overhead transmission lines. However, almost all of the existing commercial carbon fiber composite cores are composed of thermosetting resins as the matrix. On the one hand, due to the curing characteristics of thermosetting resins, the production and processing speed of the composite cores is limited. Generally, the processing speed is about <3 m / min. On the other hand, thermosetting resins are prone to curing cross-linking during the processing, forming an insoluble three-dimensional structure, which affects the subsequent recycling of products.

[0003] Using thermoplastic resins to replace thermosetting resins as the matrix materials of composite cores can well solve the above deficiencies. However, in order to make the physical properties of thermoplastic composite cores reach or even exceed those of thermosetting composite cores, the selected thermoplastic resins (plastics) need to have high melting points and high molecular weights (high melt viscosities), which increases the difficulty and manufacturing cost of composite core forming and affects their application in the field of overhead conductors. Patent CN103858181A uses thermoplastic prepreg tapes for pultrusion molding of composite cores, increasing the product process flow and cost; Patent CN104010783A uses resin transfer molding (RTM) to prepare thermoplastic composites, and different types of resin matrices are prepared by adjusting the monomer composition, but this type of solution still fails to prepare continuous fiber-reinforced composites. Summary of the Invention

[0004] In view of the above-mentioned disadvantages of the prior art, the purpose of the present invention is to provide a fiber-reinforced resin composite core for overhead conductors and a preparation method thereof, which are used to solve the problems in the prior art such as difficult impregnation of thermoplastic resins, long process flow and high cost of pultrusion molding of thermoplastic prepregs, and the inability of traditional RTM methods to prepare continuous fiber composites.

[0005] To achieve the above purpose and other related purposes, the present invention provides a fiber-reinforced resin composite core for overhead conductors, which is prepared by compounding components including reinforcing fibers and thermoplastic resins. The reinforcing fibers are selected from one or more of carbon fibers, glass fibers, basalt fibers, and alumina fibers; the thermoplastic resin is prepared from components including a prepolymer, a chain extender, and a catalyst.

[0006] Preferably, the prepolymer is prepared from components including diisocyanate and long-chain diol.

[0007] Preferably, the chain extender is selected from one or more of short-chain diols and diamines.

[0008] Preferably, the catalyst is selected from one or more of alkyltin compounds and alkylbismuth compounds.

[0009] Preferably, the molar ratio of the prepolymer to the chain extender is 1.10 - 1.40.

[0010] Preferably, the addition amount of the catalyst is 0.05% - 0.3% of the weight of the thermoplastic resin.

[0011] Preferably, the number of monofilament fibers in a single bundle of the reinforcing fibers is 3 - 59K.

[0012] Preferably, the volume content of the reinforcing fibers in the composite core is 30% - 80%.

[0013] The present invention also provides a method for preparing a fiber-reinforced resin composite core for an overhead conductor as described above, comprising the following steps:

[0014] S1. Pre-tension the reinforcing fibers and unwind them from the creel under a uniform tension state. After preheating and dehumidifying, spray and moisten the catalyst in the state of unwinding the yarn, and then enter the pultrusion die.

[0015] S2. Mix the prepolymer and the chain extender in the thermoplastic resin evenly and then heat it. Then disperse it evenly into the pultrusion die, so that the reinforcing fibers complete resin infiltration and in-situ polymerization, and cool and shape to obtain a fiber-reinforced thermoplastic resin.

[0016] Preferably, in step S2, the heating temperature is 140 - 200 °C.

[0017] Preferably, in step S2, the cooling and shaping temperature is 20 - 40 °C.

[0018] As described above, the fiber-reinforced resin composite core for an overhead conductor of the present invention and its preparation method have the following beneficial effects:

[0019] By using a thermoplastic resin to replace the thermosetting resin in the prior art, the fiber-reinforced resin composite core for an overhead conductor of the present invention improves the molding speed and the production efficiency of the composite core; meanwhile, it solves the deficiencies such as difficult impregnation of traditional thermoplastic resins.

[0020] The preparation method of the fiber-reinforced resin composite core for an overhead conductor of the present invention realizes the stable and rapid preparation of the fiber-reinforced thermoplastic composite core through the pultrusion process. Specific embodiments

[0021] The following describes the embodiments of the present invention through specific examples. Those skilled in the art can easily understand the other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through different specific embodiments. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0022] When a numerical range is disclosed herein, the above range is considered continuous and includes the minimum and maximum values of the range, as well as each value between such minimum and maximum values. Further, when the range refers to integers, it includes each integer between the minimum and maximum values of the range. In addition, when multiple ranges are provided to describe features or characteristics, the ranges can be combined. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any and all sub-ranges subsumed therein. For example, the specified range from "1 to 10" should be considered to include any and all sub-ranges between the minimum value 1 and the maximum value 10. Exemplary sub-ranges of the range 1 to 10 include, but are not limited to, 1 to 6.1, 3.5 to 7.8, 5.5 to 10, etc.

[0023] In addition, it should be understood that one or more method steps mentioned in the present invention do not exclude the existence of other method steps before and after the combined steps or the insertion of other method steps between these explicitly mentioned steps, unless otherwise specified; moreover, unless otherwise specified, the numbers of the method steps are only convenient tools for identifying the method steps, rather than limiting the arrangement order of the method steps or the scope in which the present invention can be implemented. The change or adjustment of their relative relationship, without substantial change in the technical content, should also be regarded as the scope in which the present invention can be implemented.

[0024] The first aspect of the present invention provides a fiber-reinforced resin composite core for an overhead conductor, which is prepared by compounding components including reinforcing fibers and a thermoplastic resin. The reinforcing fibers are selected from one or more of carbon fibers, glass fibers, basalt fibers, and alumina fibers; the thermoplastic resin is prepared from components including a prepolymer, a chain extender, and a catalyst.

[0025] In some embodiments of the present invention, the prepolymer is prepared from components including a diisocyanate and a long-chain diol.

[0026] Among them, the long-chain diol is selected from one or more of polycarbonate diol, polycaprolactone diol, and polyether diol.

[0027] The number-average molecular weight of the long-chain diol is 300 to 2000. For example, it is 300 to 500, 500 to 800, 800 to 1000, 1000 to 1300, 1300 to 1500, 1500 to 1800 or 1800 to 2000.

[0028] In some embodiments of the present invention, the chain extender is selected from one or more of short-chain diols and diamines.

[0029] Among them, the short-chain diol is selected from one or more of aliphatic diols and aromatic diols. The aliphatic diol is selected from one or more of 1,4-butanediol, ethylene glycol, propylene glycol, neopentyl glycol, 1,4-cyclohexanediol, and decahydronaphthalene diol; the aromatic diol is selected from one or more of hydroquinone bis(2-hydroxyethyl) ether, dihydroxyethyl terephthalate, resorcinol bis(2-hydroxyethyl) ether, and dihydroxynaphthalene.

[0030] The diamine is selected from one or more of aliphatic diamines and aromatic diamines. The aliphatic diamine is selected from one or more of ethylenediamine, pentanediamine, decanediamine, 1,3-cyclohexanedimethanamine, 1,4-cyclohexanedimethanamine, 4,4'-diaminodicyclohexylmethane, 4,4'-isopropylbicyclohexylamine, and isophorone diamine; the aromatic diamine is selected from one or more of 4,4'-diamino-3,3'-dichlorodiphenylmethane, m-xylylenediamine, p-xylylenediamine, 4,4'-diaminodiphenylmethane, and 3,3'-dimethyl-4,4'-diaminodiphenylmethane.

[0031] In some embodiments of the present invention, the chain extender further includes a polyol or polyamine with a functionality > 2.

[0032] In some embodiments of the present invention, the catalyst is selected from one or more of alkyltin compounds and alkylbismuth compounds. In a preferred embodiment of the present invention, the catalyst is selected from stannous diacetate, stannous dioctanoate, stannous dilaurate, bismuth caprylate, and bismuth decanoate. In a more preferred embodiment of the present invention, the catalyst is dibutyltin dilaurate (DBTDL).

[0033] The addition amount of the catalyst is 0.05% to 0.3% of the weight of the thermoplastic resin. For example, it is 0.05% to 0.1%, 0.1% to 0.15%, 0.15% to 0.2%, 0.2% to 0.25%, or 0.25% to 0.3%.

[0034] The molar ratio of the prepolymer to the chain extender is 1.10 to 1.40. For example, it is 1.10 to 1.15, 1.15 to 1.20, 1.20 to 1.25, 1.25 to 1.30, 1.30 to 1.35, or 1.35 to 1.40.

[0035] In some embodiments of the present invention, the number of monofilament fibers in a single bundle of the reinforcing fibers is 3 to 59K. For example, it is 3 to 5K, 5 to 10K, 10 to 12K, 12 to 15K, 15 to 20K, 20 to 25K, 25 to 30K, 30 to 35K, 35 to 40K, 40 to 45K, 45 to 50K, 50 to 55K, or 55 to 59K. In a preferred embodiment of the present invention, the number of monofilament fibers in a single bundle of the reinforcing fibers is 12K.

[0036] In some embodiments of the present invention, the volume content of the reinforcing fibers in the composite core is 30% to 80%. For example, it is 30% to 35%, 35% to 40%, 40% to 45%, 45% to 50%, 50% to 55%, 55% to 60%, 60% to 65%, 65% to 70%, 70% to 75%, or 75% to 80%.

[0037] The second aspect of the present invention provides a method for preparing a fiber-reinforced resin composite core for an overhead conductor as described above, comprising the following steps:

[0038] S1. Pre-tension the release of the reinforcing fibers, release them from the yarn rack under a uniform tension state, preheat and dehumidify, spray and moisten the catalyst in the state of spreading the yarn, and then enter the pultrusion die.

[0039] S2. Mix the prepolymer and the chain extender in the thermoplastic resin evenly and then heat, and then disperse them evenly into the pultrusion die, so that the reinforcing fibers complete resin infiltration and in-situ polymerization, and cool and shape to obtain a fiber-reinforced thermoplastic resin.

[0040] In some embodiments of the present invention, in step S2, the heating temperature is 140 to 200°C. For example, it is 140 to 145°C, 145 to 150°C, 150 to 155°C, 155 to 160°C, 160 to 165°C, 165 to 170°C, 170 to 175°C, 175 to 180°C, 180 to 185°C, 185 to 190°C, 190 to 195°C, or 195 to 200°C.

[0041] In some embodiments of the present invention, in step S2, the cooling and shaping temperature is 20 to 40°C. For example, it is 20 to 25°C, 25 to 30°C, 30 to 35°C, or 35 to 40°C.

[0042] The following material components used in the examples of the present invention are all commercially available conventional and commonly used products.

[0043] Reinforcing fiber: carbon fiber, Hexcel IM7, 12K.

[0044] Thermoplastic resin: It includes component prepolymer, chain extender and catalyst. The prepolymer includes component diisocyanate, diol 1 or diol 2; the chain extender includes chain extender 1 or chain extender 2;

[0045] Diisocyanate: BASF Lupranate MM 103C, carbodiimide-modified MDI;

[0046] Diol 1: Ube polycarbonate diol UH-CARB50, number average molecular weight 500;

[0047] Diol 2: Mitsubishi polyether diol PTMG350, number average molecular weight 305±20;

[0048] Chain extender 1: BASF 1,4-butanediol BDO;

[0049] Chain extender 2: Mitsubishi 1,3-cyclohexanedimethanamine;

[0050] Chain extender 3: A mixture of 1,4-butanediol and glycerol in a molar ratio of 10:1;

[0051] Catalyst: Sinopharm dibutyltin dilaurate DBTDL.

[0052] Examples 1 to 6

[0053] Preparation of a fiber-reinforced resin composite core for an overhead conductor:

[0054] S1. Pre-tension the release of the reinforcing fiber (carbon fiber, Hexcel IM7, 12K), release multiple bundles of fibers from the creel under a uniform tension state, preheat and dehumidify at 150°C, spray the catalyst in the spreading state, and then enter the pultrusion die;

[0055] S2. Mix the prepolymer (diisocyanate and diol) and the chain extender in the thermoplastic resin through a twin-screw, heat at 180°C, and then uniformly disperse and enter the pultrusion die. The forming speed of the composite core is 5 m / min, and it is cooled and formed at 30°C to obtain the fiber-reinforced resin composite core.

[0056] The raw material components used in Examples 1 to 6 are as shown in Table 1 below, where the molar ratio of diisocyanate:diol:chain extender is 6.8:1:5.8, and the addition ratio of the catalyst is 0.1% of the weight of the thermoplastic resin.

[0057] Table 1

[0058]

[0059] Comparative Example 1

[0060] Direct pultrusion molding is adopted for the thermoplastic prepreg tape described in Patent CN103858181A. The selected prepreg tape is Toray TAC TC1100, a unidirectional prepreg tape with a PPS (polyphenylene sulfide) matrix; the pultrusion temperature is 280°C and the pultrusion speed is 5 m / min. The difference between Comparative Example 1 and the examples lies in: different preparation methods and different thermoplastic resins.

[0061] In the examples and comparative examples of the present invention, the inner cavity diameter of the pultrusion die used is 7.8 mm.

[0062] Performance test:

[0063] Density test standard: GB / T 1463 standard; tensile strength and elastic modulus test standard: GB / T 29234 (the test standards are all the latest standards). The test results are shown in Table 2.

[0064] Table 2

[0065]

[0066]

[0067] It can be seen from the data of Examples 1 to 6, Comparative Example 1 and Tables 1 to 2 that: the tensile strength and elastic modulus of all examples and comparative examples meet the requirements of GB / T 29234, and the physical properties of the examples are improved to a certain extent compared with the comparative examples, showing the effectiveness of the fiber-reinforced resin composite core for overhead conductors of the present invention.

[0068] In summary, the fiber-reinforced resin composite core for overhead conductors prepared by the present invention has good tensile strength and elastic modulus, and the molding speed and production efficiency are improved compared with the prior art. Therefore, the present invention effectively overcomes various disadvantages in the prior art and has high industrial utilization value.

[0069] The above examples only illustrate the principles and effects of the present invention by way of example, and are not intended to limit the present invention. Any person familiar with this technology can modify or change the above examples without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or changes made by those with ordinary knowledge in the technical field without departing from the spirit and technical idea disclosed by the present invention should still be covered by the claims of the present invention.

Claims

1. A fiber-reinforced resin composite core for an overhead conductor, characterized in that, It is prepared by compounding components including reinforcing fibers and a thermoplastic resin, and the reinforcing fibers are selected from one or more of carbon fibers, glass fibers, basalt fibers, and alumina fibers; the thermoplastic resin is prepared from components including a prepolymer, a chain extender, and a catalyst.

2. The fiber-reinforced resin composite core for overhead conductors according to claim 1, wherein The prepolymer is prepared from components including a diisocyanate and a long-chain diol.

3. The fiber-reinforced resin composite core for an overhead conductor according to claim 2, wherein, The long-chain diol is selected from one or more of polycarbonate diol, polycaprolactone diol, and polyether diol; and / or, the number-average molecular weight of the long-chain diol is 300 to 2000.

4. The fiber-reinforced resin composite core for an overhead conductor according to claim 1, characterized in that, The chain extender is selected from one or more of short-chain diols and diamines.

5. The fiber-reinforced resin composite core for overhead conductors according to claim 5, characterized in that, The short-chain diol is selected from one or more of aliphatic diols and aromatic diols; and / or, the diamine is selected from one or more of aliphatic diamines and aromatic diamines.

6. The fiber-reinforced resin composite core for overhead conductors according to claim 5, characterized in that, The chain extender further includes a polyol or polyamine with a functionality > 2.

7. The fiber-reinforced resin composite core for overhead conductors according to claim 1, characterized in that, The catalyst is selected from one or more of alkyltin compounds and alkylbismuth compounds; and / or, the molar ratio of the prepolymer to the chain extender is 1.10 to 1.40; and / or, the addition amount of the catalyst is 0.05% to 0.3% of the weight of the thermoplastic resin.

8. The fiber-reinforced resin composite core for an overhead conductor according to claim 1, characterized in that, The number of monofilaments in a single bundle of the reinforcing fibers is 3 to 59K; and / or, the volume content of the reinforcing fibers in the composite core is 30% to 80%.

9. A preparation method of a fiber-reinforced resin composite core for an overhead conductor according to any one of claims 1 to 8, characterized in that, It includes the following steps: S1. Release the reinforcing fibers with pre-tension, unwind them from the creel under a uniform tension state, preheat and dehumidify them, spray and moisten the catalyst in a yarn spreading state, and then enter the pultrusion die. S2. Mix the prepolymer and the chain extender in the thermoplastic resin evenly and then heat them, and then disperse them evenly into the pultrusion die, so that the reinforcing fibers complete resin infiltration and in-situ polymerization, and are cooled and shaped to obtain a fiber-reinforced thermoplastic resin.

10. The preparation method of the fiber-reinforced resin composite core for overhead conductors according to claim 9, characterized in that, In step S2, the heating temperature is 140 to 200 °C; and / or, in step S2, the cooling and shaping temperature is 20 to 40 °C.

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