A high-toughness PP cable material and its preparation method

Abstract

This application relates to a high-toughness PP cable material and its preparation method. It comprises the following components: polypropylene-I 55.0-60.0%; polypropylene-II 25.0-30.0%; polyolefin elastomer 10.0-15.0%; antioxidant 0.1-0.5%; lubricant 0.1-0.5%; and color masterbatch 0.8-1.2%. It is prepared by the following method: the polyolefin elastomer, antioxidant, and lubricant are premixed, then mixed with polypropylene-I, polypropylene-II, and halloysite nanotubes and fed into a twin-screw extruder. The mixture is melt-extruded at 200-220°C, cooled with water, and then pelletized to obtain the final product. This application overcomes the problem of decreased material rigidity caused by simple blended elastomers during toughening by rationally combining components such as polypropylene-I, polypropylene-II, and polyolefin elastomers, and adding halloysite nanotubes. It improves the toughness of PP cable materials while effectively balancing other properties such as strength, modulus, and hardness, and also enhances heat resistance and dimensional stability, achieving an optimized improvement in comprehensive performance. Moreover, the preparation process is stable and easy for large-scale production.

Description

Technical Field

[0001] This application relates to the field of cable material technology, and more specifically to a PP cable material with high toughness and its preparation method. Background Technology

[0002] Polypropylene (PP) is increasingly widely used in the cable industry due to its advantages such as low density, good processing performance, good insulation, and chemical corrosion resistance. However, ordinary PP is brittle at room temperature, especially at low temperatures, and is prone to brittle cracking, making it difficult to meet the requirements of harsh environments such as high-altitude and cold regions, mobile laying, and rail transit for the impact resistance and crack resistance of cable sheath materials.

[0003] Currently, the most common toughening methods are simple blending of elastomers, but simple blending has drawbacks: due to the weak interfacial bonding force between non-polar PP and elastomers and poor compatibility, stress cannot be effectively transferred; at the same time, while significantly improving toughness, it often leads to a significant decrease in rigidity indicators such as strength, modulus, and hardness of the material, making it difficult to balance comprehensive performance; in addition, high amounts of elastomer may cause changes in melt strength, affecting processability.

[0004] Therefore, while significantly improving the toughness of PP, balancing other properties as much as possible has become a technical challenge that urgently needs to be solved in this field. Summary of the Invention

[0005] To address the aforementioned problems, this application provides a PP cable material with high toughness and a method for preparing the same.

[0006] Firstly, the PP cable material with high toughness provided in this application adopts the following technical solution:

[0007] A high-toughness PP cable material, by weight percentage, comprises the following components: polypropylene-I 55.0-60.0%; polypropylene-II 25.0-30.0%; polyolefin elastomer 10.0-15.0%; antioxidant 0.1-0.5%; lubricant 0.1-0.5%; and color masterbatch 0.8-1.2%.

[0008] Furthermore, the PP cable material also includes 0.05-0.1% halloysite nanotubes.

[0009] Furthermore, the polyolefin elastomer is composed of 99.1% POE 875L and 0.9% POE-g-MAH.

[0010] Furthermore, the polyolefin elastomer is composed of 99.1% POE 875L and 0.9% POE-g-MAH.

[0011] Furthermore, the polypropylene-I is obtained by blending PP-g-Furan with a polymaleimide crosslinking agent; the polypropylene-II is PP K8003.

[0012] Furthermore, the polypropylene-I is specifically prepared through the following preparation steps:

[0013] S1. Dissolve PP particles, initiator, and furan methacrylate monomer in xylene and carry out solution grafting reaction at 120-140℃ for 2-4 hours. After the reaction is completed, pour the solution into excess acetone to precipitate, filter, and wash with acetone several times to remove homopolymer and unreacted monomer. Finally, vacuum dry to obtain PP-g-Furan.

[0014] S2. The PP-g-Furan obtained in S1 is fully premixed with the polymaleimide crosslinking agent and additives in a high-speed mixer, and then fed into a twin-screw extruder for melt blending, and then extruded and granulated to obtain the final product.

[0015] Furthermore, the antioxidant is composed of a compound system of 1010 and 168, wherein the compounding ratio of antioxidant 1010 to antioxidant 168 is 1:1.

[0016] Furthermore, the lubricant is EBS; the color masterbatch is extra black masterbatch 2014B.

[0017] By adopting the above technical solution, the problem that simple blended elastomers significantly improve toughness but cause a significant decrease in rigidity indicators such as material strength, modulus, and hardness is overcome. By rationally combining components such as polypropylene-I, polypropylene-II, and polyolefin elastomers, and adding halloysite nanotubes, toughness is improved while balancing other properties of the material as much as possible, thus achieving optimization of comprehensive performance.

[0018] Halloysite nanotubes are added to PP cable materials at a ratio of 0.05-0.1%. Their unique tubular structure can form a special network structure inside the material. This structure can not only effectively prevent crack propagation, but also consume a large amount of energy through its own pull-out and fracture mechanisms when subjected to external impact, thereby significantly improving the toughness of the material. At the same time, due to its nanoscale effect, halloysite nanotubes can also be uniformly dispersed in the matrix, with little impact on the rigidity indicators such as the strength and modulus of the material. This helps to maintain a certain rigidity of the material while increasing toughness, thus achieving a preliminary balance between toughness and rigidity.

[0019] The polyolefin elastomer is composed of 99.1% POE 875L and 0.9% POE-g-MAH. POE 875L itself has good flexibility and elasticity, and can form soft phase regions in the material. When the material is subjected to external force, these soft phase regions can undergo large deformation, absorb energy, and effectively improve the impact resistance of the material. The addition of POE-g-MAH plays a key compatibilizer role. The maleic anhydride groups on its molecular chain can chemically react with the PP molecular chain, enhancing the bonding between PP and POE. The interfacial bonding force between 875L and the polyolefin elastomer forms a more uniform dispersion system, further optimizing the toughening effect. In addition, the polyolefin elastomer and halloysite nanotubes work together. The network structure of the halloysite nanotubes can limit the excessive deformation of the polyolefin elastomer phase region, avoiding the material performance degradation caused by excessive deformation of the elastomer. At the same time, the soft phase region of the polyolefin elastomer can also alleviate the stress concentration around the halloysite nanotubes. The two work synergistically to achieve more efficient toughening and performance stability. Polypropylene-I is obtained by blending PP-g-Furan with a domaleimide crosslinking agent. The furan group reacts chemically with the domaleimide to form a crosslinked structure. This crosslinked structure gives polypropylene-I a high molecular weight and a complex network structure, which not only improves the strength and modulus of the material, but also enhances the heat resistance and dimensional stability of the material. Furthermore, polypropylene-I has good compatibility with polyolefin elastomers and halloysite nanotubes. Its crosslinked structure can interpenetrate with the soft phase region of the polyolefin elastomer and the network structure of the halloysite nanotubes to form a more compact structural system, further improving the overall performance of the material.

[0020] PP K8003 was selected as polypropylene-II, which provides the basic performance support for the entire material system. PPK8003 has good processing performance and certain mechanical properties, and can be uniformly mixed with other components to form a stable material structure. When compounded with polypropylene-I, polyolefin elastomer and halloysite nanotubes, polypropylene-II acts as a continuous phase, uniformly dispersing other components within it, ensuring the integrity and uniformity of the material, and complementing other components to achieve an optimized balance in terms of toughness, rigidity and processing performance.

[0021] Secondly, the preparation method of a high-toughness PP cable material provided in this application adopts the following technical solution:

[0022] A method for preparing a PP cable material with high toughness includes the following steps:

[0023] Polyolefin elastomer, antioxidant and lubricant are premixed, and then mixed with polypropylene-I, polypropylene-II and halloysite nanotubes and fed into a twin-screw extruder for melt extrusion at 200-220℃. After cooling with water, the mixture is granulated to obtain the final product.

[0024] By adopting the above technical solutions and utilizing reasonable raw material matching and process design, the synergistic effect of each component can be fully utilized, which can not only significantly improve the toughness of the material, but also effectively balance its comprehensive performance, ensuring the stability and consistency of product quality, and providing a reliable guarantee for the large-scale production of high-performance PP cable materials.

[0025] In summary, this application has the following beneficial effects:

[0026] 1. While traditional simple blending of elastomers to toughen PP cable materials can improve toughness, it leads to a significant decrease in rigidity indicators such as strength, modulus, and hardness, making it difficult to meet the needs of complex real-world applications. This application overcomes this problem by carefully combining components such as polypropylene-I, polypropylene-II, and polyolefin elastomers, and cleverly adding halloysite nanotubes. The unique tubular structure of halloysite nanotubes forms a special network within the material, preventing crack propagation, consuming external force energy, and significantly improving toughness. Simultaneously, its nanoscale effect ensures uniform dispersion in the matrix, minimizing its impact on rigidity indicators and maintaining a certain level of material rigidity. POE-g-MAH in the polyolefin elastomer acts as a compatibilizer, enhancing the interfacial bonding between PP and POE 875L. Synergistically working with halloysite nanotubes, it further optimizes the toughening effect and stabilizes performance. The cross-linked structure of polypropylene-I, the soft phase region of the polyolefin elastomer, and the network structure of the halloysite nanotubes interpenetrate to form a compact structural system, achieving a highly efficient balance between toughness and rigidity.

[0027] 2. In this application, polypropylene-I is obtained by blending PP-g-Furan with a polymaleimide crosslinking agent. Its crosslinking structure increases the molecular weight and complexity, which not only enhances the strength and modulus, but also improves the heat resistance and dimensional stability. PPK8003 provides basic performance support for the material system, has good processing performance and certain mechanical properties, and forms a stable structure when uniformly mixed with other components. The components cooperate and complement each other to achieve an optimized balance in terms of toughness, rigidity, heat resistance, dimensional stability and processing performance, so that the material can better adapt to the use requirements in harsh environments such as high-altitude and cold regions, mobile laying, and rail transportation.

[0028] 3. The preparation method provided in this application has been scientifically designed and optimized. Every step of the process, from raw material premixing to extrusion granulation, has been carefully considered. The polyolefin elastomer, antioxidant, and lubricant are premixed first, and then mixed with other raw materials and fed into a twin-screw extruder for melt extrusion at a temperature of 200-220℃. Finally, the mixture is cooled with water and granulated. This reasonable combination of raw materials and process design ensures that the components can be fully and uniformly dispersed and interact in the material, so that each batch of PP cable material produced has stable and consistent performance. This effectively avoids product quality differences caused by uneven raw material dispersion or process fluctuations, and provides reliable quality assurance for large-scale production. Detailed Implementation

[0029] To more clearly illustrate the present invention, the following description, in conjunction with preferred embodiments, further clarifies the invention. It should be understood that the described embodiments are merely some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0030] The purpose of the present invention will be illustrated by the following examples. The components of the composition are described in parts by weight as a general standard. Unless otherwise specified, for the sake of brevity, "parts" and parts by weight are the same in the embodiments of the present invention.

[0031] Unless otherwise specified in the examples, the procedures should be performed under standard conditions or conditions recommended by the manufacturer. All reagents and instruments used, unless otherwise specified below, are commercially available products.

[0032] Examples 1-8

[0033] The raw materials used in the preparation of a high-toughness PP cable material and their amounts (%) are shown in the table below.

[0034]

[0035] The polyolefin elastomer in the above raw materials consists of 99.1% POE 875L and 0.9% POE-g-MAH; the polypropylene-II is PP K8003; polypropylene-I is obtained by blending PP-g-Furan with a dommaniimide crosslinking agent, and the specific preparation steps are as follows:

[0036] Take 100g PP, 2g DCP and 15g FMA, and react them in xylene solution at 130℃ for 3h. After the reaction is completed, pour the solution into excess acetone to precipitate, filter, and wash with acetone several times to remove homopolymer and unreacted monomers. Finally, dry under vacuum to obtain PP-g-Furan. The furan grafting rate was measured to be 1.8mol%.

[0037] Take 80 parts of the above PP-g-Furan, 8 parts of bismaleimide crosslinking agent BMI, and 0.5 parts of antioxidant 1010 and premix them thoroughly in a high-speed mixer. Then put them into a twin-screw extruder at 100°C for melt blending for 8 minutes, and then extrude and granulate to obtain the final product.

[0038] The aforementioned high-toughness PP cable material is prepared using the following method:

[0039] The polyolefin elastomer, antioxidant, and lubricant are premixed according to a predetermined amount, and then mixed with polypropylene-I, polypropylene-II, and halloysite nanotubes and fed into a twin-screw extruder for melt extrusion at a temperature of 200-220℃. The temperature of zone 1 is controlled at 200℃, the temperature of zones 2-5 is controlled at 220℃, the temperature of zones 6-9 is controlled at 215℃, and the die temperature is controlled at 220℃. The mixture is then cooled by water, with the cooling water pressure controlled at 0.3-0.5MPa, the vacuum degree maintained at <-0.08MPa, the water passage length controlled at 3-4m, and the water temperature <60℃. Finally, the pellets are pelletized at a speed of 800-1200 rpm, resulting in pellets with a size of 3×3mm*mm.

[0040] Performance tests were conducted on the PP cable materials prepared in Examples 1-8 above, and the specific test results are shown in the table below.

[0041]

[0042]

[0043]

[0044] As can be seen from the table above, the high-toughness PP cable materials prepared in Examples 1-8 exhibit good and stable performance compared to typical values ​​in various performance tests: In terms of physical properties, the test values ​​of specific gravity, melt flow index, tensile strength, flexural strength, elongation at break, flexural modulus, and cantilever beam notched impact strength all closely fluctuate around the typical values ​​with small fluctuations, demonstrating a high degree of consistency in material properties, and excellent overall mechanical properties, combining toughness and rigidity; in terms of flame retardant properties, all examples achieve the UL 94 standard HB level consistent with the typical values, meeting safety requirements; the processing parameters also conform to the reasonable range corresponding to the typical values, are easy to control, and can ensure the production of high-quality products; Example 8 shows the best performance among all examples and can be used as the preferred example.

[0045] Example 9

[0046] A PP cable material with high toughness is prepared in a manner basically the same as in Example 2, except that the polyolefin elastomer is composed only of POE 875L.

[0047] Example 10

[0048] A PP cable material with high toughness is prepared in a manner basically the same as in Example 2, except that the polyolefin elastomer is composed of 50% POE 875L and 50% POE-g-MAH.

[0049] Example 11

[0050] A PP cable material with high toughness is prepared in a manner basically the same as in Example 2, except that polypropylene-I is PP 533N.

[0051] Comparative Example 1

[0052] A high-toughness PP cable material is prepared in a manner similar to that in Example 2, with the only difference being the different raw materials used in its preparation. Details are shown in the table below.

[0053]

[0054]

[0055] Polypropylene is obtained by blending PP-g-Furan with a polymaleimide crosslinking agent.

[0056] Comparative Example 2

[0057] A high-toughness PP cable material is prepared in a manner similar to that in Example 2, with the only difference being the different raw materials used in its preparation. Details are shown in the table below.

[0058]

[0059] The polypropylene is PP K8003.

[0060] Performance tests were conducted on the PP cable materials prepared in Examples 9-11 and Comparative Examples 1-2. The specific test results are shown in the table below.

[0061]

[0062]

[0063] As can be seen from the table above, compared with the typical values ​​and the relevant characteristics of Example 2, the PP cable materials prepared in Examples 9-11 and Comparative Examples 1-2 show differences in many aspects.

[0064] The specific gravity of Examples 9-11 and Comparative Examples 1-2 is higher than the typical value of 0.90, indicating that the adjustment of the raw material formula has increased the material density. The melt index of each case is lower than the typical value of 10.5 g / 10 min, indicating that the material processing fluidity has deteriorated. Among them, Comparative Example 1 has the lowest value, and its fluidity is most affected.

[0065] The tensile strength, elongation at break, flexural strength, flexural modulus, and notched impact strength of the cantilever beam in Examples 9-11 and Comparative Examples 1-2 were all lower than the typical values, and the decrease in Comparative Examples 1-2 was more significant. This indicates that the type of polypropylene and the composition of the polyolefin elastomer have a greater impact on the mechanical properties of the material. The raw material formulation of Example 2 has a greater advantage in mechanical properties.

[0066] All cases achieved the HB level of the UL 94 standard, consistent with the typical value, indicating that the adjustment of the raw material formula did not have a significant negative impact on the flame retardant performance.

[0067] Examples 9 and Comparative Example 1 exceed the typical drying temperature range of 80-90℃, while Example 10 is below this range, indicating that changes in raw materials can affect drying temperature control. Example 10 is shorter than the typical drying time range, while Comparative Example 1 exceeds this range, indicating that different raw material formulations require different drying times. Examples 9, 11, and Comparative Example 1 exceed the typical range of 190-240℃, showing that changes in raw materials have a significant impact on melting temperature, which is detrimental to the stable control of processing temperature.

[0068] The above are all modifications that can be made to this embodiment without contributing any inventive step, or solutions that clearly constitute technical teaching, after reading this specification. However, as long as they are within the scope of the claims of this application, they should be protected by patent law.

Claims

1. A PP cable material with high toughness, characterized in that, Based on weight percentage, it includes the following components: Polypropylene-I 55.0-60.0%; Polypropylene-II 25.0-30.0%; Polyolefin elastomer 10.0-15.0%; Antioxidant 0.1-0.5%; Lubricant 0.1-0.5%; Masterbatch 0.8-1.2%; Halloysite nanotubes 0.05-0.1%; The polyolefin elastomer is composed of 99.1% POE 875L and 0.9% POE-g-MAH; The polypropylene-I is obtained by blending PP-g-Furan with a polymaleimide crosslinking agent; the polypropylene-II is PPK8003; PP-g-Furan is obtained through the following preparation steps: PP particles, initiator, and furan methacrylate monomer were dissolved in xylene and subjected to a solution grafting reaction at 120-140℃ for 2-4 hours. After the reaction was completed, the solution was poured into excess acetone to precipitate, filtered, and washed repeatedly with acetone to remove homopolymer and unreacted monomers. Finally, the solution was dried under vacuum to obtain PP-g-Furan.

2. The high-toughness PP cable material according to claim 1, characterized in that, The polypropylene-I is obtained through the following preparation steps: The obtained PP-g-Furan was premixed with a polymaleimide crosslinking agent and additives in a high-speed mixer, then fed into a twin-screw extruder for melt blending, and then extruded and granulated to obtain the final product.

3. The PP cable material with high toughness according to claim 1, characterized in that, The antioxidant is composed of a compound system of 1010 and 168, wherein the compounding ratio of antioxidant 1010 to antioxidant 168 is 1:

1.

4. The PP cable material with high toughness according to claim 1, characterized in that, The lubricant is EBS; the masterbatch is extra black masterbatch 2014B.

5. The method for preparing the high-toughness PP cable material according to any one of claims 1-4, characterized in that, Includes the following steps: Polyolefin elastomer, antioxidant and lubricant are premixed, and then mixed with polypropylene-I, polypropylene-II and halloysite nanotubes and fed into a twin-screw extruder for melt extrusion at 200-220℃. After cooling with water, the mixture is granulated to obtain the final product.

Images