阅读说明：本技术 一种低烟无卤阻燃隔热材料及其在采煤机光电复合橡套软电缆中应用 (Low-smoke halogen-free flame-retardant heat-insulating material and application thereof in photoelectric composite rubber jacketed flexible cable of coal mining machine ) 是由 王义军 苏培生 李广凯 张娟 段洋洋 宋佳 张晶 翟丽娜 王昕哲 于 2020-11-12 设计创作，主要内容包括：本发明属于电缆加工应用技术领域,尤其涉及一种低烟无卤阻燃隔热材料及其在采煤机光电复合橡套软电缆中应用。包括线芯总成以及包裹在线芯总成外的内护套层,所述内护套层外依次套装有弹性阻燃层、包裹层以及外护套层,其中,所述弹性阻燃层为低烟无卤阻燃隔热材料。本发明通过对气凝胶做改性处理,提供其硬度,同时,将其加入到聚氨酯发泡材料中,进而提高聚氨酯发泡材料的强度的同时,利用其弹性形成对电缆的弹性保护,提高整个电缆的抗弯曲性能和抗干扰能力能力,同时,利用无机硅阻燃剂形成低烟无卤的结构设计,满足现有采煤机的使用。(The invention belongs to the technical field of cable processing and application, and particularly relates to a low-smoke halogen-free flame-retardant heat-insulating material and application thereof in a photoelectric composite rubber jacketed flexible cable of a coal mining machine. Including sinle silk assembly and parcel inner sheath layer outside the sinle silk assembly, the outer cover in proper order of inner sheath layer is equipped with elasticity fire-retardant layer, parcel layer and oversheath layer, wherein, elasticity fire-retardant layer is low smoke and zero halogen fire-retardant insulation material. According to the invention, the aerogel is subjected to modification treatment to provide the hardness, and meanwhile, the aerogel is added into the polyurethane foam material, so that the strength of the polyurethane foam material is improved, meanwhile, the elasticity of the aerogel is utilized to form elastic protection on a cable, the bending resistance and the anti-interference capability of the whole cable are improved, and meanwhile, the inorganic silicon flame retardant is utilized to form a low-smoke halogen-free structural design, so that the use of the existing coal mining machine is satisfied.)

1. A low-smoke halogen-free flame-retardant heat-insulating material is characterized by comprising the following effective steps:

a. adding alumina powder and inorganic silicon flame retardant powder into tetraethoxysilane, heating and stirring until the mixture is uniformly dispersed, and uniformly stirring;

b. after stirring uniformly, adding absolute ethyl alcohol and deionized water into tetraethoxysilane, mixing according to a certain mass ratio, and stirring for 10min by magnetic force;

c. dropwise adding dilute hydrochloric acid (0.1mol/L), continuously stirring for 30min, sealing the mixed solution, and hydrolyzing at a certain temperature for a period of time;

d. after the hydrolysis is finished, dropwise adding a certain amount of N, N-dimethylformamide and dilute ammonia water into the mixed solution to obtain alcogel;

e. drying for 3h at 40 ℃ and 10MPa by adopting a supercritical drying technology to obtain hard aerogel;

f. adding the obtained hard aerogel into polyether polyol, and foaming the polyether polyol serving as a white material and the polyisocyanate serving as a black material according to a mass ratio of 1-2: 1 under the action of a cross-linking agent, a catalyst and a foaming agent to obtain the low-smoke halogen-free flame-retardant heat-insulating material with the thickness of 0.1-0.2 mm.

2. The low-smoke zero-halogen flame-retardant heat-insulating material as claimed in claim 1, wherein in the step b, the molar ratio of the tetraethoxysilane to the absolute ethyl alcohol to the deionized water is 1:7: 2.

3. The low-smoke zero-halogen flame-retardant heat-insulating material according to claim 2, wherein in the step a, the doping amounts of the alumina powder and the inorganic silicon flame retardant are 5 wt% and 7 wt%, respectively.

4. The low-smoke zero-halogen flame-retardant heat-insulating material as claimed in claim 3, wherein the molar ratio of the N, N-dimethylformamide, the diluted ammonia water and the ethyl orthosilicate is 0.5:0.09: 1.

5. The low smoke zero halogen flame retardant and heat insulating material of claim 4, wherein in the step c, the hydrolysis temperature is 40 ℃.

6. The photoelectric composite rubber jacketed flexible cable for the coal mining machine, which is made of the low-smoke halogen-free flame-retardant heat-insulating material according to the claim 5, is characterized by comprising a wire core assembly and an inner jacket layer wrapped outside the wire core assembly, wherein an elastic flame-retardant layer, a wrapping layer and an outer jacket layer are sequentially sleeved outside the inner jacket layer, and the elastic flame-retardant layer is the low-smoke halogen-free flame-retardant heat-insulating material according to the claim 5.

7. The shearer photoelectric composite rubber jacketed flexible cable of claim 6, wherein the inner jacket layer is a halogen-free EVA jacket material extruded inner jacket.

8. The shearer photoelectric composite rubber-sheathed flexible cable according to claim 6, wherein the wrapping layer is formed by winding aramid yarns.

9. The photoelectric composite rubber jacketed flexible cable for coal mining machines according to claim 6, characterized in that the outer jacket layer is a low-smoke halogen-free EVA jacket material.

Technical Field

The invention belongs to the technical field of cable processing and application, and particularly relates to a low-smoke halogen-free flame-retardant heat-insulating material and application thereof in a photoelectric composite rubber jacketed flexible cable of a coal mining machine.

Background

Coal is one of important energy sources in China, the power demand is increased increasingly along with the continuous development of economic construction in China, the coal consumption is increased increasingly, coal is a mineral energy source existing in nature, and the reserve of the coal is large in China, particularly the coal resources in Xinjiang, inner Mongolia and Shanxi in China are particularly rich.

It is a mineral resource in nature and buried in deep underground. In the past, people use artificial mining and all coal mining machines in the coal mining industry of China to mine, and the frequency conversion technology is applied to the field of coal mines more and more widely along with the development of scientific technology. Because the shearer moves back and forth rather than being stationary during the coal mining process, the shearer and the power control cabinet are far away and need to be connected by a long cable. The coal mining machine moves back and forth, left and right in the coal mining process, when the coal mining machine reaches the foremost end, the coal mining machine needs to move backwards and leftwards, and the cable can be seriously bent and dragged in the shape of 8 and S in the process of moving backwards and leftwards. When the cable is bent, the inner ring wire core of the cable is subjected to large pressure, the outer ring wire core of the cable is subjected to large tension, and large longitudinal tension is formed on the cable when the coal mining machine walks. The cable of the coal mining machine is divided into a power wire core and a control wire core, and the control wire core is thin and easy to break, so that the frequency conversion system of the coal mining machine is interfered by other power signals during working, the whole machine cannot run, and a large amount of toxic gas can be released during fire. Thus, on one hand, the coal mining machine system should have the protection function for cable bending and mechanical impact, certain anti-interference capability and no toxic gas release during combustion, and under the severe conditions of underground, on the other hand, the cable has certain bending resistance, mechanical impact resistance, interference resistance and no toxic gas release performance during combustion, namely, the cable is bent for a certain specific radius, continuously for thousands of times or even ten thousands of times and has no mechanical impact under a certain condition, a scene picture of a working face can be transmitted to the ground, the cable can still keep normal operation, the cable conductor, particularly a control core conductor, is not broken, and the insulating and sheath materials are not cracked, and have certain interference resistance and no toxic gas release performance during combustion. No cable special for the coal mining machine, which has excellent bending resistance and interference resistance and does not release toxic gas during combustion, exists so far.

Disclosure of Invention

Aiming at the technical problems of the special cable for the coal mining machine, the invention provides a low-smoke halogen-free flame-retardant heat-insulating material which is reasonable in design, simple in structure, convenient to process, capable of effectively providing bending resistance and anti-interference capability and low in smoke and halogen, and application of the low-smoke halogen-free flame-retardant heat-insulating material in a photoelectric composite rubber jacketed flexible cable for the coal mining machine.

In order to achieve the purpose, the invention adopts the technical scheme that the invention provides a low-smoke halogen-free flame-retardant heat-insulating material, which comprises the following effective steps:

a. adding alumina powder and inorganic silicon flame retardant powder into tetraethoxysilane, heating and stirring until the mixture is uniformly dispersed, and uniformly stirring;

b. after stirring uniformly, adding absolute ethyl alcohol and deionized water into tetraethoxysilane, mixing according to a certain mass ratio, and stirring for 10min by magnetic force;

c. dropwise adding dilute hydrochloric acid (0.1mol/L), continuously stirring for 30min, sealing the mixed solution, and hydrolyzing at a certain temperature for a period of time;

d. after the hydrolysis is finished, dropwise adding a certain amount of N, N-dimethylformamide and dilute ammonia water into the mixed solution to obtain alcogel;

e. drying for 3h at 40 ℃ and 10MPa by adopting a supercritical drying technology to obtain hard aerogel;

f. adding the obtained hard aerogel into polyether polyol, and foaming the polyether polyol serving as a white material and the polyisocyanate serving as a black material according to a mass ratio of 1-2: 1 under the action of a cross-linking agent, a catalyst and a foaming agent to obtain the low-smoke halogen-free flame-retardant heat-insulating material with the thickness of 0.1-0.2 mm.

Preferably, in the step b, the molar ratio of the ethyl orthosilicate to the absolute ethyl alcohol to the deionized water is 1:7: 2.

Preferably, in the step a, the doping amounts of the alumina powder and the inorganic silicon flame retardant are 5 wt% and 7 wt%, respectively.

Preferably, the molar ratio of the N, N-dimethylformamide to the diluted ammonia water to the ethyl orthosilicate is 0.5:0.09: 1.

Preferably, in the step c, the hydrolysis temperature is 40 ℃.

The invention also provides a coal mining machine photoelectric composite rubber sleeve flexible cable applying the low-smoke halogen-free flame-retardant heat-insulating material, which comprises a wire core assembly and an inner sheath layer wrapped outside the wire core assembly, wherein an elastic flame-retardant layer, a wrapping layer and an outer sheath layer are sequentially sleeved outside the inner sheath layer, and the elastic flame-retardant layer is the low-smoke halogen-free flame-retardant heat-insulating material.

Preferably, the inner sheath layer is an extruded inner sheath made of halogen-free EVA sheath material.

Preferably, the wrapping layer is formed by winding aramid yarns.

Preferably, the outer jacket layer is a low-smoke halogen-free EVA jacket material.

Compared with the prior art, the invention has the advantages and positive effects that,

1. the invention provides a low-smoke halogen-free flame-retardant heat-insulating material, which is characterized in that aerogel is modified to provide hardness, and meanwhile, the aerogel is added into a polyurethane foam material, so that the strength of the polyurethane foam material is improved, meanwhile, the elasticity of the polyurethane foam material is utilized to form elastic protection for a cable, the bending resistance and the anti-interference capability of the whole cable are improved, meanwhile, an inorganic silicon flame retardant is utilized to form a low-smoke halogen-free structural design, and the use of the existing coal mining machine is satisfied.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without inventive labor.

Fig. 1 is a schematic structural diagram of a photoelectric composite rubber jacketed flexible cable of a coal mining machine provided in example 1;

in the above figures, 1, an inner sheath layer; 2. an elastic flame retardant layer; 3. a wrapping layer; 4. an outer jacket layer; 5. A power core conductor; 6. an insulating layer; 7. a metal shielding layer; 8. a ground core conductor; 9. an optical cable; 10. an optical cable armor layer; 11. an optical cable braid; 12. an optical cable insulation layer; 13. a control wire core conductor; 14. controlling the core conductor insulation layer; 15. and (4) coating.

Detailed Description

In order that the above objects, features and advantages of the present invention can be more clearly understood, the present invention will be further described with reference to the accompanying drawings and examples. It should be noted that the embodiments and features of the embodiments of the present application may be combined with each other without conflict.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, however, the present invention may be practiced in other ways than those specifically described herein, and therefore the present invention is not limited to the specific embodiments of the present disclosure.

Example 1, as shown in fig. 1, this example provides a photoelectric composite rubber jacketed flexible cable for a coal mining machine

Considering that the main problem of the existing cable is mainly the problem of low bending resistance and other properties caused by the materials used in the protective layer, for this reason, the embodiment provides a low-smoke halogen-free flame-retardant heat insulation material first

Firstly, adding alumina powder and inorganic silicon flame retardant powder into tetraethoxysilane, heating and stirring until the alumina powder and the inorganic silicon flame retardant powder are uniformly dispersed, and stirring uniformly, wherein the addition amount of the alumina powder is 5 wt% of the finished product of the hard aerogel, the inorganic silicon flame retardant powder is 7 wt% of the finished product of the hard aerogel, and the aerogel is a solid material with a nano porous skeleton structure formed by mutually crosslinking nano particles or polymer molecules, has unique nano-scale skeleton and pore distribution characteristics, and endows the material with excellent thermophysical properties, so the material has wide application in many fields. However, the intrinsic brittleness of aerogel limits its wide application to a great extent, for which the strength of aerogel is increased by the addition of alumina powder, the flame retardant effect of whole aerogel is improved by inorganic silicon flame retardant powder, and SiO is prepared using tetraethoxysilane as silicon source₂An aerogel.

After the mixture is uniformly stirred, adding absolute ethyl alcohol and deionized water into tetraethoxysilane according to the molar ratio of 7:2:1 for mixing, and performing magnetic stirring for 10min, wherein researches show that when the molar ratio of tetraethoxysilane to deionized water is 1:2, the tetraethoxysilane and the deionized water are hydrolyzed and reversely mixedThe hydrolysis should be accelerated at a temperature of 40 ℃. For this reason, this molar ratio was selected in this example. Then, dropwise adding dilute hydrochloric acid (0.1mol/L), continuously stirring for 30min, sealing the mixed solution, and hydrolyzing for a period of time at a certain temperature; in the presence of absolute ethyl alcohol as a solvent, the hydrolysis reaction of ethyl orthosilicate and deionized water is carried out. The hydrolysis of ethyl orthosilicate generates silicon oxide, and the existence of dilute hydrochloric acid as a catalyst finds that the hydrochloric acid catalyzes SiO under the acidic catalysis₂The integrity of the aerogel is significantly improved and the gelling speed is increased.

After the hydrolysis is finished, dropwise adding a certain amount of N, N-dimethylformamide and diluted ammonia water into the mixed solution to obtain the alcogel, wherein the diluted ammonia water exists as an alkaline catalyst to improve the gelling speed, and the N, N-dimethylformamide is used as a drying control chemical additive to reduce the surface tension of the pore solution, increase the pore radius, narrow the pore size distribution and shorten the gelling time. Because the diluted ammonia water is used as a catalyst, and the N, N-dimethylformamide is used as a drying control chemical additive, the proportion is small, and the N, N-dimethylformamide, the diluted ammonia water and the tetraethoxysilane are prepared according to the molar ratio of 0.5:0.09: 1.

Then, a supercritical drying technique is adopted to dry the aerogel for 3 hours at 40 ℃ and 10MPa to obtain the hard aerogel, and the supercritical drying technique belongs to the existing common technique, so the detailed description is omitted in the embodiment. The hard aerogel with better toughness is obtained by the implementation of the process.

The hard aerogel belongs to the existence of particles and needs a certain carrier, so that the obtained hard aerogel is added into polyether polyol, and the polyether polyol serving as a white material and the polyisocyanate serving as a black material are foamed under the action of a cross-linking agent, a catalyst and a foaming agent according to the mass ratio of 1-2: 1 to obtain the low-smoke halogen-free flame-retardant heat-insulating material with the thickness of 02-0.5 mm.

Polyether polyol and polyisocyanate are common materials for preparing polyurethane foam, and the polyether polyol and the polyisocyanate play a role of a cross-linking agent in the forming process of triethanolamine, so that the foaming time is shortened, the diameter of a product cell is reduced along with the increase of the content of the product cell, the apparent density, the thermal conductivity, the compressive strength, the tensile strength and the bending strength are increased, and the elongation at break is reduced; in the embodiment, the existence of the hard aerogel plays a role in filling air holes, meanwhile, macropores are changed into nanopores, the strength of the whole material is further improved, the connection of the macropore walls and the hard aerogel is utilized to form a bridging effect, the impact force received is relieved, the impact resistance of a cable of the whole material is further improved, and the problem of cable heat conduction is solved by the high heat insulation performance of the hard aerogel, meanwhile, inorganic silicon is adopted to achieve the purpose of flame retardance.

In order to apply the low-smoke halogen-free heat-insulating material to the cable, the photoelectric composite rubber jacketed flexible cable for the coal mining machine provided by the embodiment comprises a cable core assembly and an inner jacket layer 1 wrapped outside the cable core assembly, wherein an elastic flame-retardant layer 2, a wrapping layer 3 and an outer jacket layer 4 are sequentially sleeved outside the inner jacket layer 1, and the elastic flame-retardant layer 2 is the low-smoke halogen-free flame-retardant heat-insulating material. Because low smoke and zero halogen flame retardant heat insulating material is the shaping of prophase processing, its technique that can't adopt the crowded package wraps up interior sheath, for this reason, in this embodiment, cut into long banding with low smoke and zero halogen flame retardant heat insulating material, utilize the winding of parcel layer 3 with its surface of sheath layer 1 including the constraint, for this reason, parcel layer 3 is formed for the aramid yarn winding. The outer sheath layer 4 is a conventional low-smoke halogen-free EVA sheath material.

In this embodiment, the core assembly includes a power core, a cabling core and a grounding core, the power core is composed of a power core conductor 5, an insulating layer 6 and a metal shielding layer 7, the insulating layer 6 is extruded on the surface of the power core conductor 5, and the metal shielding layer 7 is arranged on the surface of the insulating layer 6; the grounding wire core consists of a grounding wire core conductor 8; the cabling core comprises a control core unit and an optical cable 9 control unit; the control wire core unit consists of a control wire core conductor 13 and a control wire core conductor insulating layer 14, wherein the control wire core conductor insulating layer 14 is extruded on the surface of the control wire core conductor 13; the optical cable control unit consists of an optical cable 9, an optical cable armor layer 10, an optical cable braid layer 11 and an optical cable insulating layer 12, wherein the optical cable armor layer 10 is wound on the surface of the optical cable 9, the optical cable braid layer 11 is arranged on the surface of the optical cable armor layer 10, and the optical cable insulating layer 12 is extruded on the surface of the optical cable braid layer 11; after the control wire core unit and the optical cable control unit are twisted, a coating layer 15 is extruded, and then a cable wire core is formed; after the power cable core, the grounding cable core and the cabling cable core are stranded into a cable, the inner sheath layer 1 is extruded, and a certain gap is reserved among the power cable core, the grounding cable core and the cabling cable core after the power cable core, the grounding cable core and the cabling cable core are stranded into the cable. The power wire core insulating layer 6, the optical cable insulating layer 12 and the control wire core conductor insulating layer 14 are high-strength rubber layers taking ethylene propylene diene monomer as a base material; the control line core cladding layer 15 and the sheath layer are high-strength sheath material layers.

An optical cable control unit is arranged in the cable core and consists of an optical cable 9, an optical cable armor layer 10, an optical cable braid layer 11 and an optical cable insulating layer 12, the optical cable armor layer 10 is wound on the surface of the optical cable 9, the optical cable braid layer 11 is arranged on the surface of the optical cable armor layer 10, the optical cable insulating layer 12 is extruded on the surface of the optical cable braid layer 11, the optical cable armor layer 10 and the optical cable braid layer 11 play a role in protecting the optical cable 9, the optical cable 9 is prevented from being damaged under the action of external forces such as tensile force, bending resistance and the like, and the acquired data such as images, gas concentration, temperature, humidity and the like can be timely uploaded to; the optical cable insulating layer 12 and the control wire core conductor 13 are made of high-strength rubber based on ethylene propylene diene monomer, and the outer insulating layer 6 has the advantages of heat resistance, ozone resistance, good flexibility, small specific weight, small hygroscopicity, high volume resistivity, high mechanical property, good low-temperature flexibility and the like.

The above description is only a preferred embodiment of the present invention, and not intended to limit the present invention in other forms, and any person skilled in the art may apply the above modifications or changes to the equivalent embodiments with equivalent changes, without departing from the technical spirit of the present invention, and any simple modification, equivalent change and change made to the above embodiments according to the technical spirit of the present invention still belong to the protection scope of the technical spirit of the present invention.