阅读说明：本技术 一种用于制备绝缘子芯棒的改性树脂、绝缘子芯棒及绝缘子 (Modified resin for preparing insulator core rod, insulator core rod and insulator ) 是由 万小东 王钧 刘建犇 陈晞 刘艳 于 2020-11-25 设计创作，主要内容包括：本申请公开了一种用于制备绝缘子芯棒的改性树脂、绝缘子芯棒及绝缘子,改性树脂包括环氧树脂10-60重量份、使环氧树脂在第一温度下固化的第一固化剂10-50重量份、使环氧树脂在低于第一温度的第二温度下固化的第二固化剂1-5重量份。通过使用不同反应活性的第一固化剂和第二固化剂复合固化环氧树脂,使得其固化放热的温度区间变宽,降低了固化过程的平均热释放速率。因此在使用改性树脂制备大直径的拉挤复合绝缘子芯棒时,能够保证芯棒表层与内层的固化速率接近,消除了固化速率不一致带来内应力引起芯棒开裂。(The application discloses modified resin for preparing an insulator core rod, the insulator core rod and an insulator, wherein the modified resin comprises 10-60 parts by weight of epoxy resin, 10-50 parts by weight of first curing agent for curing the epoxy resin at a first temperature, and 1-5 parts by weight of second curing agent for curing the epoxy resin at a second temperature lower than the first temperature. The first curing agent and the second curing agent with different reactivities are used for compositely curing the epoxy resin, so that the temperature range of curing heat release of the epoxy resin is widened, and the average heat release rate in the curing process is reduced. Therefore, when the large-diameter pultrusion composite insulator core rod is prepared by using the modified resin, the curing rates of the surface layer and the inner layer of the core rod can be ensured to be close, and the cracking of the core rod caused by the internal stress due to the inconsistent curing rates is eliminated.)

1. The modified resin for preparing the insulator core rod is characterized by comprising 10-60 parts by weight of epoxy resin, 10-50 parts by weight of first curing agent for curing the epoxy resin at a first temperature and 1-5 parts by weight of second curing agent for curing the epoxy resin at a second temperature lower than the first temperature.

2. The modified resin of claim 1, wherein the first curing agent comprises a modified amine having the chemical formula shown in formula 1:

in formula 1, R1 is any one of the following structures:

r2 is any one of the following structures:

3. the modified resin of claim 1, wherein the second curing agent comprises a modified imidazole having a chemical formula as shown in formula 2 or formula 3:

R₃-R₄

formula 3

In formulas 2 and 3, R3 is any one of the following structures:

in formula 3, R4 is any one of the following structures:

4. the modified resin of claim 1, further comprising 1 to 5 parts by weight of an internal mold release agent.

5. An insulator core rod, characterized in that the preparation raw material comprises the modified resin of any one of claims 1 to 4.

6. The insulator core rod of claim 5, wherein the preparation method comprises the steps of:

a preparation step of providing a fiber and the modified resin;

and a preparation step of immersing the fibers in the modified resin, and then performing pultrusion and curing molding to obtain the insulator core rod.

7. The insulator core rod of claim 6,

in the preparation step, the product after the solidification and molding is subjected to gradient cooling.

8. The insulator core rod of claim 7,

in the preparation step, a cooling device is adopted for gradient cooling, the cooling device is provided with a containing cavity for the product to pass through, and the cooling device is configured to adjust the temperature in the containing cavity according to the temperature of the product passing through the containing cavity.

9. The insulator core rod of claim 5,

in the insulator core rod, the mass percentage of the fibers is 65-85%.

10. An insulator comprising an insulator core rod according to any one of claims 4 to 9.

Technical Field

The application relates to the technical field of power equipment manufacturing, in particular to modified resin for preparing an insulator core rod, the insulator core rod and an insulator.

Background

The core rod of the composite insulator is usually prepared by adopting a pultrusion process of resin-based composite materials. The traditional pultrusion process generally has the defect of product cracking in the process of preparing the large-diameter pultruded insulator core rod. On one hand, in the pultrusion process, the forming temperature inside and outside the core rod is influenced by heating and heat transfer, so that the curing rates of the inner layer and the outer layer of the product are different, and the internal stress is generated inside the material. When the internal stresses exceed the strength of the material, the article will fail to form a crack defect. On the other hand, in pultrusion, the product is exposed to room temperature for natural cooling after being separated from a pultrusion die, and the product is cracked due to thermal shock caused by the huge temperature difference between the die and the room temperature.

Content of application

The application provides a modified resin, insulator plug and insulator for preparing insulator plug, can avoid insulator plug fracture.

In a first aspect, embodiments of the present application provide a modified resin for preparing an insulator core rod, including 10 to 60 parts by weight of an epoxy resin, 10 to 50 parts by weight of a first curing agent for curing the epoxy resin at a first temperature, and 1 to 5 parts by weight of a second curing agent for curing the epoxy resin at a second temperature lower than the first temperature.

In some of these embodiments, the first curing agent comprises a modified amine having the chemical formula shown in formula 1:

in formula 1, R1 is any one of the following structures:

r2 is any one of the following structures:

in some embodiments, the second curing agent comprises a modified imidazole, which has a chemical formula shown in formula 2 or formula 3:

R₃-R₄

formula 3

In formulas 2 and 3, R3 is any one of the following structures:

in formula 3, R4 is any one of the following structures:

in some of these embodiments, the modified resin further comprises 1 to 5 parts by weight of an internal mold release agent.

In a second aspect, embodiments of the present application provide an insulator core rod, and the preparation raw material includes the modified resin in any one of the above embodiments.

In some embodiments, the preparation method of the insulator core rod comprises the following steps: a preparation step, providing fibers and modified resin. And the preparation step comprises the steps of immersing the fibers into the modified resin, and then carrying out pultrusion and curing molding to obtain the insulator core rod.

In some embodiments, in the preparation step, the product after solidification and forming is subjected to gradient cooling.

In some of these embodiments, gradient cooling is performed using a cooling device having a receiving chamber for the product to pass through, the cooling device being configured to adjust the temperature in the receiving chamber according to the temperature of the product passing through the receiving chamber.

In some embodiments, the mass ratio of the fibers in the insulator core rod is 65-85%.

In a third aspect, an embodiment of the present application provides an insulator, including the insulator core rod in any one of the above embodiments.

The modified resin for preparing the insulator core rod comprises 10-60 parts by weight of epoxy resin, 10-50 parts by weight of first curing agent for curing the epoxy resin at a first temperature, and 1-5 parts by weight of second curing agent for curing the epoxy resin at a second temperature lower than the first temperature. The first curing agent and the second curing agent with different reactivities are used for compositely curing the epoxy resin, so that the temperature range of curing heat release of the epoxy resin is widened, and the average heat release rate in the curing process is reduced. Therefore, when the large-diameter pultrusion composite insulator core rod is prepared by using the modified resin, the curing rates of the surface layer and the inner layer of the core rod can be ensured to be close, and the cracking of the core rod caused by the internal stress due to the inconsistent curing rates is eliminated.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative efforts.

Fig. 1 is a schematic structural diagram of a production system in an embodiment of the present application.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application more apparent, the present application is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application.

Embodiments of the present application provide a modified resin for preparing an insulator core rod, including 10-60 parts by weight (e.g., 100g, 200g, 600g) of an epoxy resin, 10-50 parts by weight (e.g., 100g, 300g, 500g) of a first curing agent for curing the epoxy resin at a first temperature, and 1-5 parts by weight (e.g., 10g, 30g, 50g) of a second curing agent for curing the epoxy resin at a second temperature lower than the first temperature.

The epoxy resin includes, but is not limited to, bisphenol A type epoxy resin, phenol formaldehyde type epoxy resin, bisphenol F type epoxy resin, AG-80 epoxy resin, AFG-90 epoxy resin, TDE-85 epoxy resin, etc.

The first curing agent can be modified amine, and the chemical structural formula of the modified amine is shown as formula 1:

in formula 1, R1 is any one of the following structures:

r2 is any one of the following structures:

the modified amine can be prepared by the Michael addition reaction of a maleimide compound and a diamine. The maleimide compound may include, but is not limited to, N-phenylmaleimide, 4-maleimidophenol. The diamine compound may include, but is not limited to, alicyclic diamines such as hydrogenated DDM, aromatic diamines such as m-phenylenediamine, diaminodiphenylmethane, diaminodiphenylsulfone, aliphatic diamines such as hexamethylenediamine or polyetheramine, and the like. The following are examples of the preparation of modified amines:

example 100 a first modified amine is prepared by michael addition reaction of N-phenylmaleimide and 4,4' -diaminodicyclohexylmethane (HMDA) at a molar ratio of 1-1.2: 1, and has a chemical structural formula shown in formula 10:

example 200, a michael addition reaction is performed between 4-maleimidophenol and diaminodiphenylmethane, and a feeding molar ratio is 1-1.1: 1 to obtain a second modified amine, wherein a chemical structural formula of the second modified amine is shown as a formula 11:

the first curing agent can be modified resin, and the chemical structural formula of the modified imidazole is shown as formula 2 or formula 3:

R₃-R₄

formula 3

In formulas 2 and 3, R3 is any one of the following structures:

in formula 3, R4 is any one of the following structures:

modified imidazoles may be prepared by the Michael addition reaction of maleimide compounds with imidazole substituents. The maleimide compound may include, but is not limited to, N-phenylmaleimide, 4-maleimidophenol. Imidazole substituents may include, but are not limited to, imidazole, 2-methylimidazole, 2-ethyl-4-methylimidazole. The following are examples of the preparation of modified imidazoles:

example 101 michael addition reaction of diphenylmethane Bismaleimide (BDM) with imidazole at a charge ratio: 1: 2-2.1, and preparing a first modified imidazole, wherein the chemical structural formula of the first modified imidazole is shown as a formula 20:

example 201 michael addition reaction of 4-maleimidophenol with 2-methylimidazole at a feed ratio: 1:1, preparing a second modified imidazole, wherein the chemical structural formula of the second modified imidazole is shown as a formula 30:

the modified resin may further include 1 to 5 parts by weight (e.g., 10g, 30g, 50g) of an internal mold release agent. The internal mold release agent may be zinc stearate.

The following are examples of the preparation of the modified resin:

example 10A first modified resin was obtained by mixing 10g of epoxy resin E-51, 10g of the first modified amine obtained in example 100, 1g of the first modified imidazole obtained in example 101, and 1g of an internal mold release agent, stirring them uniformly, and degassing the mixture for 5 min.

Example 20A second modified resin was obtained by mixing 30g of the epoxy resin TDE-85, 25g of the second modified amine obtained in example 200, 3g of the second modified imidazole obtained in example 201, and 3g of the internal mold release agent, followed by stirring and degassing for 5 min.

Example 30A third modified resin was obtained by blending 60g of the epoxy resin AFG-90, 50g of the second modified amine obtained in example 200, 5g of the second modified imidazole obtained in example 101, and 5g of the internal mold release agent, stirring them uniformly, and degassing the mixture for 5 min.

The first curing agent and the second curing agent with different reactivities are used for compositely curing the epoxy resin, so that the temperature range of curing heat release of the epoxy resin is widened, and the average heat release rate in the curing process is reduced. Therefore, when the modified resin is used for preparing the large-diameter pultrusion composite insulator core rod, the curing rates of the surface layer and the inner layer of the core rod can be close to each other, and the cracking of the core rod caused by internal stress due to the inconsistent curing rates is eliminated.

The embodiment of the application also provides an insulator core rod, and the preparation raw material comprises the modified resin in any one of the embodiments. The preparation raw materials may further include fibers, and in this case, the insulator core rod may be prepared through a pultrusion process.

The fibers include, but are not limited to, glass fibers, quartz fibers, basalt fibers, and kevlar fibers. The form of the fiber includes but is not limited to fiber yarn, fiber cloth, fiber belt, fiber felt, fiber woven sleeve, fiber three-dimensional fabric and the like.

The preparation method of the insulator core rod can comprise the following steps: a preparation step, providing fibers and modified resin. And the preparation step comprises the steps of immersing the fibers into the modified resin, and then carrying out pultrusion and curing molding to obtain the insulator core rod. Referring to fig. 1, the preparation of the insulator core rod may be completed by a production system 1, where the production system 1 includes a guide roller 10, a glue groove 20, a preforming device 30, a mold 40, and a traction device 50.

In the preparation step, the product after solidification and molding is subjected to gradient cooling, so that cracking caused by internal stress generated by quenching after the product is demoulded is eliminated.

In the preparation step, a temperature reduction device 60 is used for gradient temperature reduction, the temperature reduction device 60 is provided with a containing cavity for the product to pass through, and the temperature reduction device 60 is configured to adjust the temperature in the containing cavity according to the temperature of the product passing through the containing cavity. Referring to fig. 1, a temperature reduction device 60 may be located between mold 40 and traction device 50. The cooling device 60 may include a temperature measuring structure 61, a heating plate 62, and a control structure. The thermometric structure 61 is configured to detect the temperature of the product passing through the containment chamber. The heating sheet 62 is configured to regulate the temperature in the receiving cavity. The control structure is configured to control the heating plate 62 to regulate the temperature in the containing cavity according to the temperature of the product detected by the temperature measuring structure 61.

In the insulator core rod, the mass percentage of the fibers is 65-85%, such as 65%, 75% and 85%.

The following is an example of the preparation of the insulator core rod:

example 1, the first modified resin obtained in example 10 was poured into a glue tank 20, and 50 to 54 glass fibers of 9600Tex were used for production, thereby obtaining a first insulation core rod. Wherein, the initial production process comprises the following steps: the inlet temperature of the die cavity is 130 ℃, the die cavity temperature is 190 ℃, the outlet temperature of the die cavity is 190 ℃, and the pultrusion rate is 50-200 mm/min. When the production is gradually stabilized, the production process is changed to the conditions that the inlet temperature of the die cavity is 150 ℃, the temperature of the die cavity is 170 ℃, the outlet temperature of the die cavity is 190 ℃ and the pultrusion rate is 300 mm/min.

Example 2, the second modified resin obtained in example 20 was poured into a glue tank 20, and 50 to 54 glass fibers of 9600Tex were used for production, thereby obtaining a second insulator plug. Wherein, the initial production process comprises the following steps: the inlet temperature of the die cavity is 150 ℃, the die cavity temperature is 190 ℃, the outlet temperature of the die cavity is 190 ℃, and the pultrusion rate is 50-200 mm/min. When the production is gradually stabilized, the production process is changed into that the inlet temperature of the die cavity is 170 ℃, the outlet temperature of the die cavity is 190 ℃ and the pultrusion speed is 300 mm/min.

The insulator core rod has more excellent heat resistance and dielectric property, and the probability of internal defects such as cracking is lower.

The following are several examples of the present application:

example 1

Carrying out Michael addition reaction on N-phenylmaleimide and 4,4' -diaminodicyclohexylmethane (HMDA) in a feeding molar ratio of 1-1.2: 1 to obtain a first modified amine, wherein the chemical structural formula of the first modified amine is shown as a formula 10:

carrying out Michael addition reaction on diphenylmethane Bismaleimide (BDM) and imidazole at a charge ratio of: 1: 2-2.1, and preparing a first modified imidazole, wherein the chemical structural formula of the first modified imidazole is shown as a formula 20:

the first modified resin is prepared by 100g of epoxy resin E-51, 100g of first modified amine, 10g of first modified imidazole and 10g of internal mold release agent, and defoaming is carried out for 5min after uniform stirring to obtain the first modified resin.

Pouring the first modified resin into a glue groove 20, and producing by using 50-54 glass fibers of 9600Tex to obtain the first insulating mandril. Wherein, the initial production process comprises the following steps: the inlet temperature of the die cavity is 130 ℃, the die cavity temperature is 190 ℃, the outlet temperature of the die cavity is 190 ℃, and the pultrusion rate is 50-200 mm/min. When the production is gradually stabilized, the production process is changed to the conditions that the inlet temperature of the die cavity is 150 ℃, the temperature of the die cavity is 170 ℃, the outlet temperature of the die cavity is 190 ℃ and the pultrusion rate is 300 mm/min.

The core rod thus produced had a glass transition temperature of 95 ℃ and a volume resistivity of 6.3 x 10¹³～1.2*10¹⁴Ω*cm

Example two

Carrying out Michael addition reaction on 4-maleimidophenol and diaminodiphenylmethane, and preparing a second modified amine with the feeding molar ratio of 1-1.1: 1, wherein the chemical structural formula of the second modified amine is shown as a formula 11:

the Michael addition reaction is carried out on 4-maleimidophenol and 2-methylimidazole at the charge ratio: 1:1, preparing a second modified imidazole, wherein the chemical structural formula of the second modified imidazole is shown as a formula 30:

preparing 300g of epoxy resin TDE-85, 240g of second modified amine, 30g of second modified imidazole and 30g of internal mold release agent, stirring uniformly, and defoaming for 5min to obtain the second modified resin.

And pouring the second modified resin into the glue groove 20, and producing by using 50-54 glass fibers of 9600Tex to obtain a second insulator core rod. Wherein, the initial production process comprises the following steps: the inlet temperature of the die cavity is 150 ℃, the die cavity temperature is 190 ℃, the outlet temperature of the die cavity is 190 ℃, and the pultrusion rate is 50-200 mm/min. When the production is gradually stabilized, the production process is changed into that the inlet temperature of the die cavity is 170 ℃, the outlet temperature of the die cavity is 190 ℃ and the pultrusion speed is 300 mm/min.

The core rod thus produced had a glass transition temperature of 107 ℃ and a volume resistivity of 8.3X 10¹³～1.6*10¹⁴Ω*cm

EXAMPLE III

Carrying out Michael addition reaction on 4-maleimidophenol and diaminodiphenylmethane, and preparing a second modified amine with the feeding molar ratio of 1-1.1: 1, wherein the chemical structural formula of the second modified amine is shown as a formula 11:

carrying out Michael addition reaction on diphenylmethane Bismaleimide (BDM) and imidazole at a charge ratio of: 1: 2-2.1, and preparing a first modified imidazole, wherein the chemical structural formula of the first modified imidazole is shown as a formula 20:

preparing 600g of epoxy resin TDE-85, 500g of second modified amine, 50g of first modified imidazole and 50g of internal mold release agent, stirring uniformly, and defoaming for 5min to obtain second modified resin.

And pouring the second modified resin into the glue groove 20, and producing by using 50-54 glass fibers of 9600Tex to obtain a second insulator core rod. Wherein, the initial production process comprises the following steps: the inlet temperature of the die cavity is 150 ℃, the die cavity temperature is 190 ℃, the outlet temperature of the die cavity is 190 ℃, and the pultrusion rate is 50-200 mm/min. When the production is gradually stabilized, the production process is changed into that the inlet temperature of the die cavity is 170 ℃, the outlet temperature of the die cavity is 190 ℃ and the pultrusion speed is 300 mm/min.

The core rod thus produced had a glass transition temperature of 124 ℃ and a volume resistivity of 9.6 x 10¹³～1.8*10¹⁴Ω*cm

The above description is only exemplary of the present application and should not be taken as limiting the present application, as any modification, equivalent replacement, or improvement made within the spirit and principle of the present application should be included in the protection scope of the present application.