High-rigidity high-toughness anti-aging MPP material, cable conduit and preparation method and application thereof

Abstract

The invention discloses a high-rigidity high-toughness anti-aging MPP material, a cable conduit and a preparation method and application thereof, and relates to the technical field of high polymer materials. The MPP material comprises the following components in parts by mass: 75-95 parts of polypropylene resin, 2-10 parts of a toughening agent, 2-6 parts of PE, 0.5-3 parts of anti-aging master batch and 2-10 parts of stiffening master batch. The reinforcing master batch is prepared from talcum powder, wollastonite and polypropylene in a mass ratio of (2.5-3.5): (0.8-1.2): (0.8-2). The polypropylene resin is used as matrix resin, the rigidity-increasing master batch is added to improve the ring stiffness of the material, the rigidity-increasing master batch can improve the rigidity and thermal stability of the material by using the talcum powder with a sheet structure, and the rigidity and hardness of the material can be improved by matching the wollastonite with a fibrous structure. Meanwhile, a small amount of PE, the flexibilizer and the anti-aging master batch are added, so that the toughness and the anti-aging property of the material can be synergistically improved.

Description

Technical Field

[0001] The present invention relates to the technical field of polymer materials, and more specifically to a high-rigidity, high-toughness, and anti-aging MPP material, a cable conduit, and a preparation method and application thereof. Background Art

[0002] Pipes are essential materials for construction projects and are widely used in various fields. Cable conduits are mainly used to contain and protect power cables. They can be laid in various complex environments such as buildings and roads. There is no need to dig a lot of mud and soil. Just drill a hole and pull the welded cable conduit through. Compared with the traditional trenching and landfilling method, it has obvious advantages.

[0003] Common cable conduits are MPP (modified polypropylene) cable conduits, which are tubes made of one or more polypropylene materials; polypropylene has excellent physical and mechanical properties and processing properties, but its disadvantages are poor toughness, low strength, and poor aging resistance. According to the requirements of DL / T802.7-2010 standard, MPP cable conduits are divided into different levels of ring stiffness requirements, SN24 level ≥ 24kPa, SN32 level ≥ 32kPa, SN40 level ≥ 40kPa, tensile strength ≥ 25MPa, elongation at break requirement ≥ 400%, and bending strength ≥ 36MPa. Ring stiffness is a comprehensive parameter of the pipeline's ability to resist external pressure loads. Usually, MPP cable conduits with high ring stiffness have low toughness. At present, the elongation at break of MPP cable conduits with high ring stiffness grades on the market can only barely meet the requirements of industry standards. The PP resin (polypropylene) used in MPP cable conduits is a material that is easy to age. It is easy to age and degrade under the action of heat, oxygen, and light, and even loses its excellent comprehensive physical properties and use value. In order to ensure the normal use of the product, it is very necessary to improve the anti-aging performance of the MPP pipe. However, the addition of anti-aging agents will affect the mechanical strength and toughness to a certain extent, and significantly reduce the ring stiffness and elongation at break. Therefore, it is of great significance to improve the anti-aging performance while ensuring the mechanical properties of the MPP cable conduit material.

[0004] A high-toughness MPP material and its preparation method and the prepared cable protection tube in the prior art, the raw materials of which include MPP and a carbonate toughening agent, and the raw materials cooperate with each other so that the prepared MPP material has good toughness, heat resistance, flame retardancy and bending properties. The elongation at break of the obtained product is 550-580%, and the ring stiffness is 45.5-46.7 kPa. However, the problem of high-temperature aging of the MPP material is not solved. Summary of the invention

[0005] The purpose of the present invention is to overcome the defects and shortcomings of existing MPP materials that cannot simultaneously take into account stiffness, toughness and high temperature aging resistance, and to provide a high stiffness, high toughness and aging resistance MPP material.

[0006] Another object of the present invention is to provide a method for preparing a high-rigidity, high-toughness and aging-resistant MPP material.

[0007] Another object of the present invention is to provide an application of the above-mentioned high-rigidity, high-toughness and aging-resistant MPP material in cable conduits.

[0008] The above-mentioned purpose of the present invention is achieved through the following technical solutions:

[0009] The present invention protects a high-rigidity, high-toughness, and anti-aging MPP material, which includes the following components by weight: 75-95 parts of polypropylene resin, 2-10 parts of toughening agent, 2-6 parts of PE, 0.5-3 parts of anti-aging masterbatch, and 2-10 parts of stiffening masterbatch;

[0010] The rigidity-enhancing masterbatch is made of talcum powder, wollastonite and polypropylene in a mass ratio of (2.5-3.5):(0.8-1.2):(0.8-2).

[0011] The present invention uses polypropylene resin as a base resin, and adds a stiffening masterbatch to improve the tensile strength and bending strength of the material; the stiffening masterbatch is made of talcum powder, wollastonite and polypropylene. The talcum powder with a flaky structure can improve the toughness, rigidity and thermal stability of the plastic, and the wollastonite is fibrous and has a strong hardness, which can improve the hardness of the plastic. The present invention compounds talcum powder, wollastonite and polypropylene and optimizes the ratio. The two fillers with different microstructures can be used to fill the gaps in the base resin to greatly improve the stiffness and hardness of the material; at the same time, the materials are first evenly dispersed and compatible, and the use of the masterbatch is more convenient for the mixing and dispersion of multiple materials in the entire formula, thereby improving the mechanical properties of the plastic. At the same time, adding a small amount of PE (polyethylene) and a toughening agent can synergistically improve the toughness of the material, which can achieve good compatibility with the base resin of polypropylene, improve the toughness of the plastic and improve the aging resistance; then adding the anti-aging masterbatch further improves the aging resistance.

[0012] Preferably, the anti-aging masterbatch is a masterbatch of antioxidant 1010 diluted 10 times with polypropylene. The masterbatch is made by diluting polypropylene, which can facilitate the dispersion of the antioxidant in the overall material and reduce the impact on the mechanical properties of the plastic.

[0013] The mass ratio of talcum powder, wollastonite and polypropylene in the rigid masterbatch of the present invention is a key parameter for improving the tensile strength, flexural strength and elongation of the material. Talc can improve the toughness, rigidity and thermal stability of plastics, but a large amount of addition is required to make the hardness meet the requirements, and too much addition will cause the problem of low dispersibility, affecting the overall mechanical properties; Wollastonite has a high hardness and can significantly improve the hardness of plastics, but excessive use will affect the toughness and easily cause excessive wear of the equipment mold; the present invention optimizes the ratio of talcum powder and wollastonite, adds an appropriate amount of polypropylene to make a rigid masterbatch, which can improve the mechanical properties and thermal stability of MPP materials.

[0014] In some embodiments, the PE (polyethylene) content is no more than 5wt.%, preferably 1-4wt.%, which can achieve good compatibility with the polypropylene matrix resin, and can enhance the toughness of the plastic and improve the aging resistance.

[0015] In some embodiments, the following components are included by weight: 80-90 parts of polypropylene resin, 3-8 parts of toughening agent, 3-5 parts of PE, 1-2 parts of anti-aging masterbatch, and 3-6 parts of stiffening masterbatch. By further optimizing the raw material ratio, the rigidity, toughness and anti-aging properties of the material are improved.

[0016] In some embodiments, the particle size of the talc and wollastonite is 2000-2500 mesh. After the inorganic powders such as talc and wollastonite are melted with plastic, they are evenly dispersed in the plastic. If the particle size of the inorganic powder is large, it will become a defect in the plastic, and it is more likely to crack, affecting the mechanical properties; if the particle size of the inorganic powder is too fine, the processing cost of the inorganic powder is too high, and the too fine inorganic powder is easy to agglomerate and difficult to disperse; through repeated tests, the inorganic powder with a particle size of 2000-2500 mesh sieve has achieved ideal results in terms of dispersibility and compatibility, as well as the rigidity and hardening performance of the plastic.

[0017] In some embodiments, the method for preparing the rigidity-enhancing masterbatch is as follows: talcum powder, wollastonite and polypropylene are uniformly mixed, and then melt-extruded and granulated to obtain the rigidity-enhancing masterbatch.

[0018] In some embodiments, the polypropylene resin is PPB (block copolymer polypropylene) and / or PPH (homopolymer polypropylene). More preferably, the carrier resin is composed of PPH and PPB in a mass ratio of (8-10):(6-8).

[0019] In some embodiments, the toughening agent is POE (polyolefin thermoplastic elastomer) and / or EPDM (ethylene propylene diene monomer). More preferably, the toughening agent is composed of POE and EPDM in a mass ratio of (4-6):(2-4).

[0020] In some embodiments, the PE is LDPE (low density polyethylene) and / or LLDPE (linear low density polyethylene).

[0021] The present invention provides a method for preparing a high-rigidity, high-toughness, and aging-resistant MPP material, comprising the following steps:

[0022] S1, taking the formulated amount of carrier resin, toughening agent, PE, stiffening masterbatch and anti-aging masterbatch and mixing them evenly to obtain a mixed material;

[0023] S2, subjecting the mixed material to melt blending and extrusion molding to obtain the MPP material. Preferably, the temperature of the melt blending is 180-210°C.

[0024] The invention discloses application of a high-rigidity, high-toughness, and anti-aging MPP material in preparing a cable conduit.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] The present invention provides a high-rigidity, high-toughness, and anti-aging MPP material, which uses polypropylene resin as a base resin, and adds a stiffening masterbatch to improve the ring stiffness of the material, wherein the stiffening masterbatch is made of talcum powder, wollastonite, and polypropylene. The use of talcum powder with a flaky structure can improve the rigidity and thermal stability of the material, and the use of wollastonite with a high-hardness fibrous structure can effectively improve the rigidity and hardness of the material. At the same time, a small amount of PE, a toughening agent, and an anti-aging masterbatch are added and the ratio is optimized, which can synergistically improve the toughness of the material and improve the heat aging resistance. DETAILED DESCRIPTION

[0027] The present invention is further described below in conjunction with specific embodiments, but the embodiments do not limit the present invention in any form. Unless otherwise specified, the raw materials and reagents used in the embodiments of the present invention are conventionally purchased raw materials and reagents.

[0028] The raw materials of the following examples or comparative examples are as follows:

[0029] 1. Polypropylene resin:

[0030] PPH resin, CNOOC Shell HP500N;

[0031] PPB resin, Hainan Refining and Chemical K8003.

[0032] 2. Polyethylene PE

[0033] LDPE, Maoming Petrochemical 951-050;

[0034] LLDPE, Maoming Petrochemical 7042.

[0035] 3. Toughening agent

[0036] POE,

[0037] EPDM,

[0038] 4. Anti-aging masterbatch: Antioxidant 1010 is diluted 10 times with polypropylene.

[0039] 5. Rigidity-enhancing masterbatch: A mixture of talcum powder, wollastonite and polypropylene raw materials that have passed a 2200 mesh sieve in a mass ratio of 3:1:1 is extruded and granulated using a parallel twin-screw extruder.

[0040] Examples 1 to 3 and Comparative Example 1

[0041] This embodiment and comparative example provide a series of high-rigidity, high-toughness, and aging-resistant MPP materials, the components of which are shown in Table 1.

[0042] Table 1 Raw material components (parts by mass)

[0043]

[0044]

[0045] The preparation method of the high-rigidity, high-toughness, and anti-aging MPP material comprises the following steps:

[0046] Take the above-mentioned raw materials in the formula amount and add them to the mixer for 15 minutes, then discharge the materials. The discharged materials are extruded on a single screw extruder, and the temperature of each zone of the extruder is set at 180-210°C. After extrusion, cooling, cutting and storage, the obtained product is obtained.

[0047] Embodiments 4 to 6

[0048] The MPP cable conduits of Examples 4 to 6 are respectively made of the high-rigidity, high-toughness, and anti-aging MPP materials of Examples 1 to 3.

[0049] Performance Testing

[0050] The tensile strength, elongation, flexural strength, oxidation induction value and ring stiffness of the MPP material samples of Examples 1 to 3 and Comparative Example 1 were tested respectively. The results are shown in Table 2.

[0051] Table 2 Performance test results

[0052]

[0053] As shown in Table 2, the tensile strength of the MPP material of the present invention reaches more than 29.0 MPa, the elongation reaches more than 480%, the bending strength reaches more than 38.2 MPa, and the oxidation induction value is more than 70.2 min. Its mechanical properties are higher than the requirements of industry standards and have significant aging properties.

[0054] The above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. 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 embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A high-rigidity, high-toughness, and anti-aging MPP material, characterized in that: The invention comprises the following components in parts by weight: 75-95 parts of polypropylene resin, 2-10 parts of toughening agent, 2-6 parts of PE, 0.5-3 parts of anti-aging masterbatch, and 2-10 parts of stiffening masterbatch; The rigidity-enhancing masterbatch is made of talcum powder, wollastonite and polypropylene in a mass ratio of (2.5-3.5):(0.8-1.2):(0.8-2).

2. The high-rigidity, high-toughness, and anti-aging MPP material according to claim 1, characterized in that: The invention comprises the following components in parts by weight: 80-90 parts of polypropylene resin, 3-8 parts of toughening agent, 3-5 parts of PE, 1-2 parts of anti-aging masterbatch and 3-6 parts of rigidity-enhancing masterbatch.

3. The high-rigidity, high-toughness, and anti-aging MPP material according to claim 1, characterized in that: The particle size of the talc powder is 2000-2500 mesh, and the particle size of the wollastonite is 2000-2500 mesh.

4. The high-rigidity, high-toughness, and anti-aging MPP material according to claim 1, characterized in that: The polypropylene resin is PPB and / or PPH.

5. The high-rigidity, high-toughness, and anti-aging MPP material according to claim 1, characterized in that: The toughening agent is POE and / or EPDM.

6. The high-rigidity, high-toughness, and anti-aging MPP material according to claim 5, characterized in that: The toughening agent is composed of POE and EPDM in a mass ratio of (4-6):(2-4).

7. The high-rigidity, high-toughness, and anti-aging MPP material according to claim 1, characterized in that: The PE is LDPE and / or LLDPE.

8. A method for preparing the high-rigidity, high-toughness, and anti-aging MPP material according to any one of claims 1 to 7, characterized in that: The following steps are involved: S1, taking the formulated amount of carrier resin, toughening agent, PE, stiffening masterbatch and anti-aging masterbatch and mixing them evenly to obtain a mixed material; S2, subjecting the mixed material to melt blending and extrusion molding, the melt blending temperature is 180-210° C., to obtain the MPP material.

9. Use of the high-rigidity, high-toughness, and anti-aging MPP material according to any one of claims 1 to 7 in the preparation of cable conduits.

10. A high-rigidity, high-toughness, and anti-aging MPP cable conduit, characterized in that: It is made of the MPP material with high rigidity, toughness and anti-aging as described in any one of claims 1 to 7.

Images