High-temperature-resistant flame-retardant cable and preparation process thereof

Abstract

The invention discloses a high-temperature-resistant flame-retardant cable and a preparation process thereof, and belongs to the technical field of cables, and the high-temperature-resistant flame-retardant cable sequentially comprises a copper conductor, an insulating layer and a flame-retardant layer coated outside the insulating layer from inside to outside; the flame-retardant layer is prepared from the following raw materials in parts by weight: 5 to 14 parts of ammonia alkali white mud, 2 to 4 parts of a coupling agent A-151, 15 to 23 parts of polyphenylene sulfide, 0.8 to 1.3 parts of 3-octanoylthio-1-propyltriethoxysilane, 5 to 8 parts of palmitic acid, 230 to 280 parts of polyethylene, 18 to 27 parts of composite flame-retardant powder, 6 to 9 parts of 3-mercaptopropyltrimethoxysilane and 1 to 4 parts of octadecanamide. Polyphenylene sulfide is modified through compounded 3-octanoylthio-1-propyltriethoxysilane and palmitic acid, so that the flame retardant property of the material is greatly enhanced, the mechanical property of the material is remarkably improved, and specifically, the tensile strength is increased in a leap manner. In addition, by introducing a hot pressing process, the stability of the material in a high-temperature environment is further consolidated.

Description

Technical Field

[0001] The present invention relates to the technical field of cables, and in particular to a high temperature resistant flame retardant cable and a preparation process thereof. Background Art

[0002] Cables are the main carriers for transmitting electrical energy, information or realizing electromagnetic conversion. They are widely used in many fields such as electricity, rail transportation, construction engineering, communications, etc. They are called the "blood vessels" of the national economy. With the rapid development of the global economy and the enhancement of human environmental awareness, various fields have higher and higher requirements for the quality and performance (such as flame retardant properties) of wires and cables.

[0003] For example, Chinese patent CN117877803B discloses a smoke-suppressing flame-retardant cable. The cable prepared by the present invention includes a conductor, a shielding layer, an insulating layer, a flame-retardant layer and an outer sheath layer from the inside to the outside, wherein the conductor is a copper conductor, the conductor shielding layer covers the copper conductor, the insulating layer covers the conductor shielding layer, the flame-retardant layer covers the insulating layer, and the outer sheath layer covers the flame-retardant layer; wherein the flame-retardant layer is coated with acrylic paint to give the cable excellent flame-retardant properties; the outer sheath layer is prepared from a sheath material, which uses PVC resin and nitrile rubber with excellent corrosion resistance as the main raw materials, and then uses magnesium hydroxide nanomaterials with excellent flame-retardant and smoke-suppressing effects as a substrate, and modifies it, further improving the flame-retardant and smoke-suppressing properties of the substrate.

[0004] However, step 2 of the above patent requires reflux for 12 hours and drying for 12 hours, and step 3 requires reaction for 12 hours, which significantly prolongs the overall production cycle, thereby affecting the further improvement of production efficiency; in addition, the high temperature resistance of the cable produced in the above patent also needs to be improved.

[0005] Based on this, the present invention designs a high temperature resistant flame retardant cable and a preparation process thereof to solve the above problems. Summary of the invention

[0006] In view of the above-mentioned shortcomings of the prior art, the present invention provides a high temperature resistant flame retardant cable and a preparation process thereof.

[0007] To achieve the above objectives, the present invention is implemented through the following technical solutions:

[0008] A high temperature resistant flame retardant cable, which comprises, from inside to outside, a copper conductor, an insulating layer, and a flame retardant layer coated outside the insulating layer;

[0009] The flame retardant layer comprises the following raw materials: 5-14 parts of ammonia-alkali white mud, 2-4 parts of coupling agent A-151, 15-23 parts of polyphenylene sulfide, 0.8-1.3 parts of 3-octanoylthio-1-propyltriethoxysilane, 5-8 parts of palmitic acid, 230-280 parts of polyethylene, 18-27 parts of composite flame retardant powder, 6-9 parts of 3-mercaptopropyltrimethoxysilane and 1-4 parts of stearic acid amide.

[0010] A method for preparing the high temperature resistant flame retardant cable comprises the following steps:

[0011] Step 1: Grind the ammonia-soda white mud, then add anhydrous ethanol to wash, and dry to obtain the ammonia-soda white mud powder;

[0012] Step 2: Add coupling agent A-151 into ammonia-alkali white mud and disperse for 20-30 minutes;

[0013] Step 3: Heat and dissolve polyphenylene sulfide, gradually dropwise add palmitic acid containing 3-octanoylthio-1-propyltriethoxysilane to form a mixed solution, react to obtain an initial film-forming solution, and degas the initial film-forming solution in a vacuum drying oven to obtain a film-forming solution;

[0014] Step 4: pouring the film-forming liquid into a mold by a casting method, and drying to obtain a palmitic acid plasticized modified polyphenylene sulfide film;

[0015] Step 5: preheating the polyphenylene sulfide film, hot pressing, releasing the pressure and letting it stand, freezing and grinding the polyphenylene sulfide film into composite flame retardant powder, and drying;

[0016] Step 6: Stir and mix the ammonia-alkali white mud, polyethylene, composite flame retardant powder, 3-mercaptopropyltrimethoxysilane and stearic acid amide in step 2 to obtain a flame retardant coating;

[0017] Step 7: Compound the insulation layer on the outer layer of the copper conductor, and apply the flame retardant coating on the outer layer of the insulation layer to form a flame retardant layer, which is a high temperature resistant flame retardant cable.

[0018] Furthermore, step one is specifically as follows: grinding 5-14 parts of ammonia-soda mud to 3-5 μm, then adding anhydrous ethanol for washing, and drying at 50-60° C. to obtain ammonia-soda mud powder.

[0019] Furthermore, step 2 is specifically as follows: 2-4 parts of coupling agent A-151 are added to the ammonia-soda white mud, and dispersed at 25-30° C. and 200-300 rpm for 20-30 minutes.

[0020] Furthermore, step three is specifically as follows: dissolving 15-23 parts of polyphenylene sulfide at 290-300° C., gradually dropping 5-8 parts of palmitic acid containing 0.8-1.3 parts of 3-octanoylthio-1-propyltriethoxysilane, and completing the dropping within 20-30 minutes to form a mixed solution, reacting for 2 hours to obtain an initial film-forming solution, and degassing the initial film-forming solution in a vacuum drying oven to obtain a film-forming solution.

[0021] Furthermore, step five is specifically as follows: preheating the polyphenylene sulfide film to 60-80°C, releasing the pressure and standing for 5-10 minutes, freezing at -2--10°C for 5-10 minutes, grinding the polyphenylene sulfide film into composite flame retardant powder, and drying at 40°C.

[0022] Furthermore, in step five, hot pressing is performed for 7-12 minutes at a pressure of 2-3 MPa.

[0023] Furthermore, step six is ​​specifically as follows: the ammonia-alkali white mud of step two, 230-280 parts of polyethylene, 18-27 parts of composite flame retardant powder, 6-9 parts of 3-mercaptopropyltrimethoxysilane and 1-4 parts of stearic acid amide are stirred and mixed for 15-20 minutes to obtain a flame retardant coating.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] The present invention modifies polyphenylene sulfide by compounding 3-octanoylthio-1-propyltriethoxysilane and palmitic acid, which not only greatly enhances the flame retardant properties of the material, making it show excellent resistance to fire, but also significantly improves its mechanical properties, specifically manifested in a leap-forward increase in tensile strength. In addition, by introducing the hot pressing process, the stability of the material in a high temperature environment is further consolidated, effectively broadening the application boundary of its high temperature resistance.

[0026] Compared with Chinese patent CN117877803B, the preparation time of the present invention is significantly shortened, and the overall production cycle is significantly shortened, thereby achieving further improvement in production efficiency. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described in combination with the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] Embodiment 1: This embodiment provides a method for preparing a high temperature resistant flame retardant cable, comprising the following steps:

[0029] The high temperature resistant flame retardant cable comprises, from inside to outside, a copper conductor, an insulating layer, and a flame retardant layer coated outside the insulating layer;

[0030] The insulating layer is made of polyvinyl chloride, and the flame retardant layer is coated with flame retardant paint;

[0031] The flame retardant coating is prepared by the following steps:

[0032] Step 1: Grind 14 parts of ammonia-soda white mud (alkali residue) to 5 μm, then add anhydrous ethanol for washing, and dry at 60° C. to obtain ammonia-soda white mud powder;

[0033] Step 2: Add 4 parts of coupling agent A-151 (vinyl triethoxysilane) into the ammonia-alkali white mud and disperse at 30°C and 300 rpm for 30 minutes;

[0034] Step 3: dissolving 23 parts of polyphenylene sulfide at 300° C., gradually dropping 8 parts of palmitic acid containing 1.3 parts of 3-octanoylthio-1-propyltriethoxysilane, and completing the dropping within 30 minutes to form a mixed solution, reacting for 2 hours to obtain an initial film-forming solution, and then degassing the initial film-forming solution in a vacuum drying oven to obtain a film-forming solution;

[0035] Step 4: pouring the film-forming liquid into a mold by a casting method, and drying to obtain a palmitic acid plasticized modified polyphenylene sulfide film;

[0036] Step 5: preheat the polyphenylene sulfide film to 80°C, hot press for 12 minutes, and the pressure is 3Mpa. After releasing the pressure, let it stand for 10 minutes, freeze it at -10°C for 10 minutes, grind the polyphenylene sulfide film into composite flame retardant powder, and dry it at 40°C;

[0037] Step 6: Stir and mix the ammonia-alkali white mud of step 2, 280 parts of polyethylene, 27 parts of composite flame retardant powder, 9 parts of 3-mercaptopropyltrimethoxysilane and 4 parts of stearic acid amide for 15-20 minutes to obtain a flame retardant coating;

[0038] Step 7: Compound the insulation layer on the outer layer of the copper conductor, and apply the flame retardant coating on the outer layer of the insulation layer to form a flame retardant layer, which is a high temperature resistant flame retardant cable.

[0039] Embodiment 2: This embodiment provides a method for preparing a high temperature resistant flame retardant cable, comprising the following steps:

[0040] The high temperature resistant flame retardant cable comprises, from inside to outside, a copper conductor, an insulating layer, and a flame retardant layer coated outside the insulating layer;

[0041] The insulating layer is made of polyvinyl chloride, and the flame retardant layer is coated with flame retardant paint;

[0042] The flame retardant coating is prepared by the following steps:

[0043] Step 1: Grind 5 parts of ammonia-soda white mud (alkali residue) to 3 μm, then add anhydrous ethanol for washing, and dry at 50° C. to obtain ammonia-soda white mud powder;

[0044] Step 2: Add 2 parts of coupling agent A-151 (vinyl triethoxysilane) to the ammonia-alkali white mud and disperse at 25°C and 200 rpm for 20 minutes;

[0045] Step 3: dissolving 15 parts of polyphenylene sulfide at 290°C, gradually adding 5 parts of palmitic acid containing 0.8 parts of 3-octanoylthio-1-propyltriethoxysilane, and dropping them all over for 20 minutes to form a mixed solution, reacting for 2 hours to obtain an initial film-forming solution, and then degassing the initial film-forming solution in a vacuum drying oven to obtain a film-forming solution;

[0046] Step 4: pouring the film-forming liquid into a mold by a casting method, and drying to obtain a palmitic acid plasticized modified polyphenylene sulfide film;

[0047] Step 5: preheat the polyphenylene sulfide film to 60°C, hot press for 7 minutes, and the pressure is 2Mpa. After releasing the pressure, let it stand for 5 minutes, freeze it at -2°C for 5 minutes, grind the polyphenylene sulfide film into composite flame retardant powder, and dry it at 40°C;

[0048] Step 6: Stir and mix the ammonia-alkali white mud of step 2, 230 parts of polyethylene, 18 parts of composite flame retardant powder, 6 parts of 3-mercaptopropyltrimethoxysilane and 1 part of stearic acid amide for 15 minutes to obtain a flame retardant coating;

[0049] Step 7: Compound the insulation layer on the outer layer of the copper conductor, and apply the flame retardant coating on the outer layer of the insulation layer to form a flame retardant layer, which is a high temperature resistant flame retardant cable.

[0050] Embodiment 3: This embodiment provides a method for preparing a high temperature resistant flame retardant cable, comprising the following steps:

[0051] The high temperature resistant flame retardant cable comprises, from inside to outside, a copper conductor, an insulating layer, and a flame retardant layer coated outside the insulating layer;

[0052] The insulating layer is made of polyvinyl chloride, and the flame retardant layer is coated with flame retardant paint;

[0053] The flame retardant coating is prepared by the following steps:

[0054] Step 1: Grind 8 parts of ammonia-soda mud (alkali residue) to 4 μm, then add anhydrous ethanol for washing, and dry at 58° C. to obtain ammonia-soda mud powder;

[0055] Step 2: Add 3 parts of coupling agent A-151 (vinyl triethoxysilane) into ammonia-alkali white mud and disperse at 28°C and 260rpm for 28min;

[0056] Step 3: dissolving 19 parts of polyphenylene sulfide at 294°C, gradually adding 6 parts of palmitic acid containing 1.1 parts of 3-octanoylthio-1-propyltriethoxysilane, and dropping the mixture for 20 minutes to form a mixed solution, reacting for 2 hours to obtain an initial film-forming solution, and then degassing the initial film-forming solution in a vacuum drying oven to obtain a film-forming solution;

[0057] Step 4: pouring the film-forming liquid into a mold by a casting method, and drying to obtain a palmitic acid plasticized modified polyphenylene sulfide film;

[0058] Step 5: preheat the polyphenylene sulfide film to 75°C, hot press for 10 minutes, and the pressure is 2.5 MPa. After releasing the pressure, let it stand for 8 minutes, freeze it at -7°C for 6 minutes, grind the polyphenylene sulfide film into composite flame retardant powder, and dry it at 40°C;

[0059] Step 6: Stir and mix the ammonia-alkali white mud of step 2, 250 parts of polyethylene, 22 parts of composite flame retardant powder, 7 parts of 3-mercaptopropyltrimethoxysilane and 2 parts of stearic acid amide for 18 minutes to obtain a flame retardant coating;

[0060] Step 7: Compound the insulation layer on the outer layer of the copper conductor, and apply the flame retardant coating on the outer layer of the insulation layer to form a flame retardant layer, which is a high temperature resistant flame retardant cable.

[0061] Comparative Example 1: The difference from Example 3 is that 3-octanoylthio-1-propyltriethoxysilane is not added;

[0062] This comparative example provides a method for preparing a high temperature resistant flame retardant cable, comprising the following steps:

[0063] The high temperature resistant flame retardant cable comprises, from inside to outside, a copper conductor, an insulating layer, and a flame retardant layer coated outside the insulating layer;

[0064] The insulating layer is made of polyvinyl chloride, and the flame retardant layer is coated with flame retardant paint;

[0065] The flame retardant coating is prepared by the following steps:

[0066] Step 1: Grind 8 parts of ammonia-soda mud (alkali residue) to 4 μm, then add anhydrous ethanol for washing, and dry at 58° C. to obtain ammonia-soda mud powder;

[0067] Step 2: Add 3 parts of coupling agent A-151 (vinyl triethoxysilane) into ammonia-alkali white mud and disperse at 28°C and 260rpm for 28min;

[0068] Step 3: dissolve 19 parts of polyphenylene sulfide at 294°C, gradually add 6 parts of palmitic acid, and drip it for 20 minutes to form a mixed solution, react for 2 hours to obtain an initial film-forming solution, and then degas the initial film-forming solution in a vacuum drying oven to obtain a film-forming solution;

[0069] Step 4: pouring the film-forming liquid into a mold by a casting method, and drying to obtain a palmitic acid plasticized modified polyphenylene sulfide film;

[0070] Step 5: preheat the polyphenylene sulfide film to 75°C, hot press for 10 minutes, and the pressure is 2.5 MPa. After releasing the pressure, let it stand for 8 minutes, freeze it at -7°C for 6 minutes, grind the polyphenylene sulfide film into composite flame retardant powder, and dry it at 40°C;

[0071] Step 6: Stir and mix the ammonia-alkali white mud of step 2, 250 parts of polyethylene, 22 parts of composite flame retardant powder, 7 parts of 3-mercaptopropyltrimethoxysilane and 2 parts of stearic acid amide for 18 minutes to obtain a flame retardant coating;

[0072] Step 7: Compound the insulation layer on the outer layer of the copper conductor, and apply the flame retardant coating on the outer layer of the insulation layer to form a flame retardant layer, which is a high temperature resistant flame retardant cable.

[0073] Comparative Example 2: The difference from Example 3 is that hot pressing is not performed in step 5;

[0074] This comparative example provides a method for preparing a high temperature resistant flame retardant cable, comprising the following steps:

[0075] The high temperature resistant flame retardant cable comprises, from inside to outside, a copper conductor, an insulating layer, and a flame retardant layer coated outside the insulating layer;

[0076] The insulating layer is made of polyvinyl chloride, and the flame retardant layer is coated with flame retardant paint;

[0077] The flame retardant coating is prepared by the following steps:

[0078] Step 1: Grind 8 parts of ammonia-soda mud (alkali residue) to 4 μm, then add anhydrous ethanol for washing, and dry at 58° C. to obtain ammonia-soda mud powder;

[0079] Step 2: Add 3 parts of coupling agent A-151 (vinyl triethoxysilane) into ammonia-alkali white mud and disperse at 28°C and 260rpm for 28min;

[0080] Step 3: dissolving 19 parts of polyphenylene sulfide at 294°C, gradually adding 6 parts of palmitic acid containing 1.1 parts of 3-octanoylthio-1-propyltriethoxysilane, and dropping the mixture for 20 minutes to form a mixed solution, reacting for 2 hours to obtain an initial film-forming solution, and then degassing the initial film-forming solution in a vacuum drying oven to obtain a film-forming solution;

[0081] Step 4: pouring the film-forming liquid into a mold by a casting method, and drying to obtain a palmitic acid plasticized modified polyphenylene sulfide film;

[0082] Step 5: preheat the polyphenylene sulfide film to 75°C, let it stand for 8 minutes, freeze it at -7°C for 6 minutes, grind the polyphenylene sulfide film into composite flame retardant powder, and dry it at 40°C;

[0083] Step 6: Stir and mix the ammonia-alkali white mud of step 2, 250 parts of polyethylene, 22 parts of composite flame retardant powder, 7 parts of 3-mercaptopropyltrimethoxysilane and 2 parts of stearic acid amide for 18 minutes to obtain a flame retardant coating;

[0084] Step 7: Compound the insulation layer on the outer layer of the copper conductor, and apply the flame retardant coating on the outer layer of the insulation layer to form a flame retardant layer, which is a high temperature resistant flame retardant cable.

[0085] Experimental example

[0086] According to GB / T 2951.42-2008 "Test for tensile strength and elongation at break after high temperature treatment", the tensile strength A0 before high temperature treatment and the tensile strength A1 after high temperature treatment are tested (the difference between A0 and A1 reflects the high temperature resistance);

[0087] Test the oxygen index according to GB / T 2406.2-2009 "Determination of combustion behavior of plastics by oxygen index method Part 2: Room temperature test" (an oxygen index less than 23 indicates that the material is flammable, and an oxygen index greater than 36 indicates that the material has high flame retardancy);

[0088] project Embodiment 1 Embodiment 2 Embodiment 3 Comparative Example 1 Comparative Example 2 Oxygen index% 37.4 38.2 37.9 35.6 36.8 A0 / MPa 14.3 14.2 13.7 12.4 13.8 A1 / MPa 14.1 13.9 13.6 12.2 11.7

[0089] The invention modifies polyphenylene sulfide by compounding 3-octanoylthio-1-propyltriethoxysilane and palmitic acid, thereby significantly improving the flame retardancy and mechanical properties (tensile strength); and effectively improving the high temperature resistance by hot pressing process.

[0090] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements will not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A high temperature resistant flame retardant cable, characterized in that: The high temperature resistant flame retardant cable comprises, from inside to outside, a copper conductor, an insulating layer, and a flame retardant layer coated outside the insulating layer; The flame retardant layer comprises the following raw materials: 5-14 parts of ammonia-alkali white mud, 2-4 parts of coupling agent A-151, 15-23 parts of polyphenylene sulfide, 0.8-1.3 parts of 3-octanoylthio-1-propyltriethoxysilane, 5-8 parts of palmitic acid, 230-280 parts of polyethylene, 18-27 parts of composite flame retardant powder, 6-9 parts of 3-mercaptopropyltrimethoxysilane and 1-4 parts of stearic acid amide.

2. A method for preparing a high temperature resistant flame retardant cable as claimed in claim 1, characterized in that: The following steps are involved: Step 1: Grind the ammonia-soda white mud, then add anhydrous ethanol to wash, and dry to obtain the ammonia-soda white mud powder; Step 2: Add coupling agent A-151 into ammonia-alkali white mud and disperse for 20-30 minutes; Step 3: Heat and dissolve polyphenylene sulfide, gradually dropwise add palmitic acid containing 3-octanoylthio-1-propyltriethoxysilane to form a mixed solution, react to obtain an initial film-forming solution, and degas the initial film-forming solution in a vacuum drying oven to obtain a film-forming solution; Step 4: pouring the film-forming liquid into a mold by a casting method, and drying to obtain a palmitic acid plasticized modified polyphenylene sulfide film; Step 5: preheating the polyphenylene sulfide film, hot pressing, releasing the pressure and letting it stand, freezing and grinding the polyphenylene sulfide film into composite flame retardant powder, and drying; Step 6: Stir and mix the ammonia-alkali white mud, polyethylene, composite flame retardant powder, 3-mercaptopropyltrimethoxysilane and stearic acid amide in step 2 to obtain a flame retardant coating; Step 7: Compound the insulation layer on the outer layer of the copper conductor, and apply the flame retardant coating on the outer layer of the insulation layer to form a flame retardant layer, which is a high temperature resistant flame retardant cable.

3. The preparation method according to claim 2, characterized in that: Step 1 is specifically as follows: grinding 5-14 parts of ammonia-soda mud to 3-5 μm, then adding anhydrous ethanol for washing, and drying at 50-60° C. to obtain ammonia-soda mud powder.

4. The preparation method according to claim 3, characterized in that: Step 2 is as follows: add 2-4 parts of coupling agent A-151 into ammonia-soda white mud, and disperse at 25-30° C. and 200-300 rpm for 20-30 minutes.

5. The preparation method according to claim 4, characterized in that: Step three is as follows: dissolving 15-23 parts of polyphenylene sulfide at 290-300°C, gradually dropping 5-8 parts of palmitic acid containing 0.8-1.3 parts of 3-octanoylthio-1-propyltriethoxysilane, and completing the dropping within 20-30 minutes to form a mixed solution, reacting for 2 hours to obtain an initial film-forming solution, and degassing the initial film-forming solution in a vacuum drying oven to obtain a film-forming solution.

6. The preparation method according to claim 5, characterized in that: Step five is as follows: preheat the polyphenylene sulfide film to 60-80°C, let it stand for 5-10 minutes after releasing the pressure, freeze it at -2--10°C for 5-10 minutes, grind the polyphenylene sulfide film into composite flame retardant powder, and dry it at 40°C.

7. The preparation method according to claim 6, characterized in that: In step five, hot pressing is performed for 7-12 minutes at a pressure of 2-3 MPa.

8. The preparation method according to claim 7, characterized in that: Step six is ​​as follows: the ammonia-alkali white mud of step two, 230-280 parts of polyethylene, 18-27 parts of composite flame retardant powder, 6-9 parts of 3-mercaptopropyltrimethoxysilane and 1-4 parts of stearic acid amide are stirred and mixed for 15-20 minutes to obtain a flame retardant coating.