Flexible flame-retardant thermoplastic polyurethane elastomer cable material and preparation method thereof

Abstract

The invention discloses a flexible flame-retardant thermoplastic polyurethane elastomer cable material and a preparation method thereof. The cable material is prepared from the following raw materials in parts by weight: 100 parts of thermoplastic polyurethane resin, 10-20 parts of polyvinyl chloride resin, 8-15 parts of a plasticizer, 1-5 parts of a flame retardant A, 5-12 parts of a flame retardant B, 25-40 parts of an inorganic filler, 1-5 parts of a heat stabilizer, 0.2-0.8 part of an antioxidant A, 0.2-0.8 part of an antioxidant B, 0.5-1 part of a processing aid, 1-5 parts of a lubricant and 2-6 parts of color master batch. The hardness of the TPU cable material is controlled to be about 85A under the condition of not changing the excellent comprehensive properties such as high strength, high elasticity and high elongation of TPU, the flame retardance of the TPU cable material is improved, and the TPU cable material which is relatively good in flame retardant effect, flexibility, mechanical property and low-temperature resistance is prepared and can pass a low-temperature impact test at the temperature of 50 DEG C below zero.

Description

Technical Field

[0001] The invention relates to the technical field of wire and cable materials, and in particular to a flexible flame-retardant thermoplastic polyurethane elastomer cable material and a preparation method thereof. Background Art

[0002] As a new type of polymer material, thermoplastic polyurethane (TPU) is composed of soft segments composed of oligomer polyols and hard segments composed of diisocyanates and small molecule chain extenders. This two-phase state makes TPU have excellent tensile strength as well as good resilience and flexibility. At the same time, TPU can be divided into polyester type and polyether type. In comparison, polyether type has more stable hydrolysis resistance. In addition, TPU has good wear resistance, high elongation, outstanding oil resistance, corrosion resistance, low temperature resistance, and long service life, so it is widely used in many fields.

[0003] As the outermost layer of the cable, the cable sheath plays a key role in protecting the safe transmission of the cable. This places high demands on the cable sheath material. Polyvinyl chloride (PVC), as a traditional polymer material, is currently one of the main cable sheath materials. Compared with PVC, TPU is more environmentally friendly, does not release chlorine or other by-products when burned, and is recyclable. Combined with the excellent comprehensive properties of TPU such as high strength, high flexibility, high elongation, and corrosion resistance, TPU has great application potential as a cable sheath material.

[0004] However, TPU itself also has certain defects. Its limiting oxygen index is lower than 21%, which makes it easy to burn and drip during the burning process. In addition, the hardness of TPU will also affect the flexibility and tensile strength of the material. If the hardness is high, the flexibility of the material will be poor, and the tensile strength will also be reduced; if the hardness is low, the result will be the opposite. Therefore, the difficulty in modifying TPU lies in finding a balance between improving the flame retardant effect of TPU itself and obtaining better flexibility and tensile strength, so as to improve the flame retardancy of TPU itself without changing the performance of the TPU cable material itself. Summary of the invention

[0005] The purpose of the present invention is to control the hardness of TPU cable material to about 85A without changing the excellent comprehensive properties of TPU itself, such as high strength, high elasticity, and high elongation, and improve its own flame retardancy to produce TPU cable material with good flame retardant effect and good flexibility. The preparation method provided has low cost, high cost performance, simple extrusion process, and the obtained cable material can be applied to cable sheaths with complex working environments, has a long safe service life, and can ensure effective transmission of power transmission lines.

[0006] The present invention adopts the following technical solution:

[0007] A flexible flame-retardant thermoplastic polyurethane elastomer cable material is prepared from the following raw materials in parts by weight:

[0008]

[0009] Preferably, the thermoplastic polyurethane resin is a hydrolysis-resistant polyether polyurethane resin.

[0010] Preferably, the volatile content of the polyvinyl chloride resin is ≤0.30% (110° C., 10 min).

[0011] Preferably, the plasticizer is dioctyl terephthalate, and its density is 0.978-0.986 g / cm 3 , flash point>210℃, volume resistivity≥1.0×10 11 Ω·cm.

[0012] Preferably, the flame retardant A is an antimony-containing flame retardant, with an average particle size of 1.000-1.300 μm, a blue light whiteness of ≥93.00%, and a water content of ≤0.10%.

[0013] Preferably, the flame retardant B is a bromine-containing flame retardant with an average particle size of 1.500-2.000 μm, a blue light whiteness of 90.00-94.00%, and a water content of ≤0.10%.

[0014] Preferably, the antioxidant A is pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, which is a white flowable powder.

[0015] Preferably, the antioxidant B is dilauryl thiodipropionate, which is in the form of white granules, powder or flakes.

[0016] Preferably, the inorganic filler is calcium carbonate, with an average particle size of ≤1.750 μm, a blue light whiteness of ≥95.50%, and a water content of ≤0.50%.

[0017] Preferably, the stabilizer is a calcium-zinc composite stabilizer, and its thermal stability time at 200° C. is ≥160 min.

[0018] Preferably, the processing aid is an acrylate, and its water content is less than 0.50%.

[0019] Preferably, the lubricant is a white powder, and the total bromine and total chromium contents thereof are both ≤1000 ppm.

[0020] Preferably, the masterbatch is a PVC black masterbatch.

[0021] A method for preparing a flexible flame-retardant thermoplastic polyurethane elastomer cable material comprises the following steps:

[0022] S1, adding each raw material component into a high-speed kneader in order according to the proportion, heating, stirring and kneading to obtain a mixture;

[0023] S2, putting the mixed material kneaded in step S1 into an extruder for extrusion granulation, and drying the mixed material to obtain the desired flexible flame-retardant thermoplastic polyurethane elastomer cable material.

[0024] Preferably, in step S1, the kneading temperature of the high-speed kneading machine is 80-100° C., and the kneading time is 5-10 min.

[0025] Preferably, in step S2, the temperature for drying the extruded granules is 70-80° C., and the drying time is 2 hours.

[0026] Preferably, in step S2, a twin-screw extruder is used for extrusion granulation, and the heating temperature of the twin-screw extruder is 150-190°C.

[0027] More preferably, the twin-screw material making machine is divided into eight heating zones, and the corresponding temperatures are first zone temperature: 150-155°C, second zone temperature: 155-160°C, third zone temperature: 160-165°C, fourth zone temperature: 165-170°C, fifth zone temperature: 165-170°C, sixth zone temperature: 165-170°C, seventh zone temperature: 165-170°C, eighth zone temperature: 165-170°C.

[0028] Compared with the prior art, the technical solution of the present invention has the following advantages:

[0029] A. The present invention further optimizes the performance of the cable material without changing the excellent properties of thermoplastic polyurethane (TPU) itself, such as high strength, high elasticity, and high elongation, so that its Shore hardness is about 85A, while maintaining good tensile strength and anti-aging performance.

[0030] B. By adding a specific flame retardant, the present invention successfully improves the flame retardancy of the TPU cable material, making it have a better flame retardant effect, thereby enhancing the safety of the cable material during use.

[0031] C. The cable material prepared by the present invention has outstanding low temperature resistance and can maintain stable performance in a complex working environment, thus ensuring safe and efficient transmission of power transmission lines.

[0032] D. The preparation method provided by the present invention has low cost and high cost performance, and the extrusion process is simple and easy to realize industrial production.

[0033] E. Since the cable material of the present invention has excellent comprehensive performance and flame retardancy, it has a long safe service life and can meet the needs of long-term use. DETAILED DESCRIPTION

[0034] The present invention can be implemented in many different forms and should not be construed as being limited to the embodiments set forth herein. Instead, these embodiments are provided so that the present disclosure will be thorough and complete and will fully convey the concept of the present invention to those skilled in the art. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work are within the scope of protection of the present invention.

[0035] Embodiment 1:

[0036] A flexible flame-retardant thermoplastic polyurethane elastomer cable material is made from the following raw materials in parts by weight:

[0037]

[0038] The preparation method of the flexible flame-retardant thermoplastic polyurethane elastomer cable material of this embodiment comprises the following steps:

[0039] S1. Add the raw material components into a high-speed kneader in order according to the proportion, heat, stir and knead, the kneading temperature of the high-speed kneader is 100° C., and the kneading time is 6 min to obtain a mixed material;

[0040] S2. The mixed material kneaded in step S1 is put into a twin-screw material maker for extrusion granulation. The granulator is divided into 8 heating zones, and the heating temperature of each zone is 150-155°C, 155-160°C, 160-165°C, 165-170°C, 170-175°C, 175-180°C, 180-185°C, and 185-190°C. The mixed material is dried at 70°C for 2 hours to obtain the desired flexible flame-retardant thermoplastic polyurethane elastomer cable material.

[0041] Embodiment 2:

[0042] A flexible flame-retardant thermoplastic polyurethane elastomer cable material is made from the following raw materials in parts by weight:

[0043]

[0044] The preparation method of the flexible flame-retardant thermoplastic polyurethane elastomer cable material of this embodiment comprises the following steps:

[0045] S1. Add the raw material components into a high-speed kneader in order according to the proportion, heat, stir and knead, the kneading temperature of the high-speed kneader is 90° C., and the kneading time is 8 min to obtain a mixed material;

[0046] S2. The mixed material kneaded in step S1 is put into a twin-screw material maker for extrusion granulation. The granulator is divided into 8 heating zones, and the heating temperature of each zone is 150-155°C, 155-160°C, 160-165°C, 165-170°C, 170-175°C, 175-180°C, 180-185°C, and 185-190°C. The mixed material is dried at 80°C for 2 hours to obtain the desired flexible flame-retardant thermoplastic polyurethane elastomer cable material.

[0047] Embodiment 3:

[0048] A flexible flame-retardant thermoplastic polyurethane elastomer cable material is made from the following raw materials in parts by weight:

[0049]

[0050] The preparation method of the flexible flame-retardant thermoplastic polyurethane elastomer cable material of this embodiment comprises the following steps:

[0051] S1. Add the raw material components into a high-speed kneader in order according to the proportion, heat, stir and knead, the kneading temperature of the high-speed kneader is 90° C., and the kneading time is 10 min to obtain a mixed material;

[0052] S2. The mixed material kneaded in step S1 is put into a twin-screw material maker for extrusion granulation. The granulator is divided into 8 heating zones, and the heating temperature of each zone is 150-155°C, 155-160°C, 160-165°C, 165-170°C, 170-175°C, 175-180°C, 180-185°C, and 185-190°C. The mixed material is dried at 75°C for 2 hours to obtain the desired flexible flame-retardant thermoplastic polyurethane elastomer cable material.

[0053] Embodiment 4:

[0054] A flexible flame-retardant thermoplastic polyurethane elastomer cable material is made from the following raw materials in parts by weight:

[0055]

[0056] The preparation method of the flexible flame-retardant thermoplastic polyurethane elastomer cable material of this embodiment comprises the following steps:

[0057] S1. Add the raw material components into a high-speed kneader in order according to the proportion, heat, stir and knead, the kneading temperature of the high-speed kneader is 80° C., and the kneading time is 5 min to obtain a mixture;

[0058] S2. The mixed material kneaded in step S1 is put into a twin-screw material maker for extrusion granulation. The granulator is divided into 8 heating zones, and the heating temperature of each zone is 150-155°C, 155-160°C, 160-165°C, 165-170°C, 170-175°C, 175-180°C, 180-185°C, and 185-190°C. The mixed material is dried at 70°C for 2 hours to obtain the desired flexible flame-retardant thermoplastic polyurethane elastomer cable material.

[0059] The cable material obtained above was tested accordingly according to the same test method, and the relevant performance results of the prepared cable material are shown in Table 1.

[0060] Table 1 Performance test of flexible flame retardant thermoplastic polyurethane cable materials

[0061]

[0062] It can be seen from the data in Table 1 that the flexible flame retardant thermoplastic polyurethane cable material of the present invention has moderate hardness, high mechanical strength, strong low temperature resistance, and good flame retardant effect. In general, the flexible flame retardant thermoplastic polyurethane cable material prepared by the present invention has good comprehensive performance. The preparation method has low cost, high cost performance, simple extrusion process, and the obtained cable material can be applied to cable sheaths with complex working environments, has a long safe service life, and can ensure effective transmission of power transmission lines.

[0063] Anything not described in the present invention is applicable to the prior art.

[0064] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. However, the obvious changes or modifications derived therefrom are still within the scope of protection of the present invention.

Claims

1. A flexible flame retardant thermoplastic polyurethane elastomer cable material, characterized in that: It is prepared from the following raw materials in parts by weight:

2. The flexible flame-retardant thermoplastic polyurethane elastomer cable material according to claim 1, characterized in that: The thermoplastic polyurethane resin is a hydrolysis-resistant polyether polyurethane resin; The volatile content of the polyvinyl chloride resin is ≤0.30% (110°C, 10min); The plasticizer is dioctyl terephthalate, and its density is 0.978-0.986 g / cm 3 , flash point>210℃, volume resistivity≥1.0×10 11 Ω·cm.

3. The flexible flame-retardant thermoplastic polyurethane elastomer cable material according to claim 1, characterized in that: The flame retardant A is an antimony-containing flame retardant with an average particle size of 1.000-1.300 μm, a blue light whiteness of ≥93.00%, and a water content of ≤0.10%; The flame retardant B is a bromine-containing flame retardant with an average particle size of 1.500-2.000 μm, a blue light whiteness of 90.00-94.00%, and a water content of ≤0.10%.

4. The flexible flame-retardant thermoplastic polyurethane elastomer cable material according to claim 1, characterized in that: The antioxidant A is pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, which is a white flowable powder; The antioxidant B is dilauryl thiodipropionate, which is in the form of white granules, powder or flakes.

5. The flexible flame-retardant thermoplastic polyurethane elastomer cable material according to claim 5, characterized in that: The inorganic filler is calcium carbonate, with an average particle size of ≤1.750 μm, a blue light whiteness of ≥95.50%, and a water content of ≤0.50%; The stabilizer is a calcium-zinc composite stabilizer, and its thermal stability time at 200° C. is ≥160 min; The processing aid is an acrylate, and its water content is less than 0.50%; The lubricant is a white powder, and its total bromine and total chromium contents are both ≤1000ppm; The masterbatch is a PVC black masterbatch.

6. A method for preparing the flexible flame-retardant thermoplastic polyurethane elastomer cable material according to any one of claims 1 to 5, characterized in that: The steps include: S1, adding each raw material component into a high-speed kneader in order according to the proportion, heating, stirring and kneading to obtain a mixture; S2, putting the mixed material kneaded in step S1 into an extruder for extrusion granulation, and drying the mixed material to obtain the desired flexible flame-retardant thermoplastic polyurethane elastomer cable material.

7. The preparation method according to claim 6, characterized in that: In the step S1, the kneading temperature of the high-speed kneading machine is 80-100° C., and the kneading time is 5-10 min.

8. The preparation method according to claim 6, characterized in that: In the step S2, the temperature for drying the extruded granules is 70-80°C, and the drying time is 2 hours.

9. The preparation method according to claim 6, characterized in that: In the step S2, a twin-screw extruder is used for extrusion granulation, and the heating temperature of the twin-screw extruder is 150-190°C.

10. The preparation method according to claim 9, characterized in that: The twin-screw material making machine is divided into eight heating zones, and the corresponding temperatures are first zone temperature: 150-155°C, second zone temperature: 155-160°C, third zone temperature: 160-165°C, fourth zone temperature: 165-170°C, fifth zone temperature: 165-170°C, sixth zone temperature: 165-170°C, seventh zone temperature: 165-170°C, and eighth zone temperature: 165-170°C.

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