Wear-resistant high-toughness polypropylene material and preparation method thereof

Abstract

The invention relates to the technical field of materials, and discloses a wear-resistant high-toughness polypropylene material and a preparation method thereof.The polypropylene material is prepared by taking polypropylene as a base material and taking a compatibilizer, an ethylene-octylene block copolymer, a mullite functional agent and the like as auxiliary materials through mixing and melt extrusion processes. Wherein the mullite functional agent is prepared by modifying the surface of mullite with a branched macromolecular polymer connected by an ester bond, and the existence of the macromolecular polymer can improve the compatibility between the mullite and a polypropylene matrix, so that the mullite can efficiently exert the self-enhancement effect, the stress deformation resistance of the material is improved, and the mechanical property of the material is improved. And the material has high-strength and high-toughness effects. Besides, the macromolecular polymer can be cross-linked with a polypropylene molecular chain, so that the structural density of the material is improved, the material has higher hardness, the grinding crack width of the material on a membrane material surface is reduced, and the wear resistance of the material is improved.

Description

Technical Field

[0001] The invention relates to the technical field of materials, and in particular to a wear-resistant high-toughness polypropylene material and a preparation method thereof. Background Art

[0002] Polypropylene (PP for short) is the second largest general-purpose synthetic resin in the world after polyethylene, with a density of only 0.90-0.91 g / cm 3 , is one of the lightest types of plastics, and this feature makes it the preferred material for lightweight daily necessities. For example, plastic basins, storage boxes and other products made of polypropylene can reduce their weight by more than 30% compared with traditional materials while maintaining sufficient strength, significantly improving user experience. It is precisely because of its light weight, heat resistance, and chemical corrosion resistance that polypropylene has shown irreplaceable advantages in the field of daily plastic products.

[0003] However, with the continuous deepening of applications, the defects of poor wear resistance and toughness of polypropylene are gradually exposed, which has a great negative impact on the service life of polypropylene plastic products. In the prior art, inorganic reinforcing agents are generally added to improve the comprehensive properties of polypropylene such as wear resistance. However, there is a natural interface incompatibility problem between the inorganic reinforcing agent and the polypropylene matrix. A small amount of addition will result in ineffective improvement, and a large amount of addition will cause agglomeration, which has a negative impact on the performance of the material. Based on this, the present invention provides a polypropylene composite material with good comprehensive properties such as wear resistance and high toughness, which can be used to manufacture daily plastic products. Summary of the invention

[0004] In order to solve the problems mentioned in the background technology, the object of the present invention is to provide a wear-resistant and high-toughness polypropylene material and a preparation method thereof.

[0005] The purpose of the present invention can be achieved through the following technical solutions:

[0006] A wear-resistant high-toughness polypropylene material, comprising the following raw materials in parts by weight:

[0007] 65-85 parts of polypropylene, 5-15 parts of compatibilizer, 5-10 parts of ethylene-octene block copolymer, 2-6.5 parts of mullite functional agent, 0.5-1.5 parts of lubricant, 0.5-1 parts of antioxidant, and 0.1-0.4 parts of initiator.

[0008] As a further embodiment of the present invention, the compatibilizer is maleic anhydride grafted polyethylene or maleic anhydride grafted polypropylene.

[0009] As a further solution of the present invention, the mullite functional agent is prepared by the following method:

[0010] Step 1: Add the epoxy group silane coupling agent to the sulfuric acid solution, stir and mix evenly. Then raise the temperature to 90 - 100 °C, keep warm for 30 - 60 min, and then lower the temperature to 40 - 50 °C. Continue to add mullite, disperse it evenly by ultrasonic wave, and then control the temperature at 80 - 90 °C, continuously stir for 3 - 6 h, cool down and discharge. After the post-treatment process, activated mullite is prepared.

[0011] Step 2: Disperse the activated mullite in N,N-dimethylformamide, introduce nitrogen for protection. Then add triphenylene-2,6,10-tricarboxylic acid, catalyst and condensing agent to the formed dispersion liquid. After adding, stir evenly by mechanical stirring. Then raise the temperature to 100 - 120 °C, keep warm and stir for 4 - 8 h, and then continue to add allyl pentaerythritol. After adding, continuously keep warm and stir for 12 - 24 h, stop heating, centrifuge to separate the solid material, and after washing and vacuum drying treatment, the mullite functional agent can be prepared.

[0012] As a further scheme of the present invention, in Step 1, the epoxy group silane coupling agent is selected from 3-glycidoxypropyltrimethylsilane or 3-glycidoxypropyltriethylsilane.

[0013] As a further scheme of the present invention, in Step 1, the pH of the sulfuric acid solution is 2 - 3.

[0014] As a further scheme of the present invention, in Step 2, the catalyst is any one of 4-dimethylaminopyridine, N-hydroxysuccinimide or 1-hydroxybenzotriazole.

[0015] As a further scheme of the present invention, in Step 2, the condensing agent is dicyclohexylcarbodiimide or 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride.

[0016] As a further scheme of the present invention, in Step 2, the mass ratio of the activated mullite, triphenylene-2,6,10-tricarboxylic acid and allyl pentaerythritol is 1:1.5 - 2.5:0.8 - 1.5.

[0017] By adopting the above technical scheme, first, the epoxy substituent in the structure of the epoxy group silane coupling agent is ring-opened with sulfuric acid to form two equivalent hydroxyl substituents. Then, the surface of the mullite is modified to form a large number of active hydroxyl substituents on the surface of the mullite, and the activated mullite is prepared. Then, taking this active hydroxyl substituent as the initiation site, under high temperature conditions, and the common action of the catalyst and the condensing agent, triphenylene-2,6,10-tricarboxylic acid and allyl pentaerythritol are initiated to carry out in-situ branched polymerization on the surface of the mullite, so as to modify the surface of the mullite with a branched macromolecular polymer connected by ester bonds, that is, the mullite functional agent.

[0018] As a further solution of the present invention, the lubricant is polyethylene wax or liquid paraffin; the antioxidant is any one of hindered phenol antioxidants or phosphite antioxidants; the initiator is benzoyl peroxide or dicumyl peroxide.

[0019] A preparation method of a wear-resistant and high-toughness polypropylene material comprises the following steps:

[0020] First step: Add each raw material weighed and prepared according to parts by weight to a high-speed mixer, set the rotation speed to 1000-2000 r / min and the temperature to 80-100 °C, mechanically stir and mix for 20-40 min, then cool down and discharge to form a premix.

[0021] Second step: Feed the premix into a twin-screw extruder through a feeding port, control the temperature at 180-230 °C and the screw rotation speed at 300-400 r / min, and carry out melt extrusion.

[0022] The beneficial effects of the present invention:

[0023] In the present invention, a branched macromolecular polymer connected by an ester bond is modified on the surface of mullite to obtain a mullite functional agent. As an additive, on the one hand, the branched structure of the macromolecular polymer contains unsaturated alkenyl substituents, which can interact with the polypropylene molecular chain during the melt extrusion process under the action of an initiator, and then form a crosslinked network with each other, thereby greatly improving the compatibility between mullite and the polypropylene matrix. Moreover, mullite will act as a rigid support point in the form of a crosslinked core, which can not only bear and transfer loads, but also improve the ability of the material to resist stress deformation, resulting in toughening and strengthening effects. In addition, the branched macromolecular polymer structure contains a large number of rigid triphenylene heterocyclic structures. The existence of this structure can improve the rigidity of the crosslinked network, and the existence of the crosslinked network can make the material show a higher structural density, making the material have a higher hardness, thereby reducing the scratch width of the material on the film surface and improving the wear resistance of the material.

[0024] Of course, it is not necessary for any product implementing the present invention to achieve all the above-mentioned advantages simultaneously. Specific embodiments

[0025] The following will clearly and completely describe the technical solutions of the present invention in conjunction with the embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0026] Example 1

[0027] A wear-resistant high-toughness polypropylene material, comprising the following raw materials in parts by weight:

[0028] 65 parts of polypropylene, 5 parts of maleic anhydride grafted polyethylene, 5 parts of ethylene-octene block copolymer, 2 parts of mullite functional agent, 0.5 parts of polyethylene wax, 0.5 parts of antioxidant 1010, and 0.1 parts of benzoyl peroxide.

[0029] The preparation method of the polypropylene material comprises the following steps:

[0030] The first step is to weigh all the prepared raw materials according to their weight and add them into a high-speed mixer, set the speed to 1000r / min and the temperature to 80°C, mechanically stir and mix for 40 minutes, cool and discharge the materials to form a premix;

[0031] The second step is to feed the premixed material into the twin-screw extruder through the feeding port, control the temperature to 220°C, and the screw speed to 300 / min for melt extrusion.

[0032] Example 2

[0033] A wear-resistant high-toughness polypropylene material, comprising the following raw materials in parts by weight:

[0034] 70 parts of polypropylene, 10 parts of maleic anhydride grafted polyethylene, 6 parts of ethylene-octene block copolymer, 6 parts of mullite functional agent, 1 part of polyethylene wax, 0.6 parts of antioxidant 1010, and 0.3 parts of benzoyl peroxide.

[0035] The preparation method of the polypropylene material comprises the following steps:

[0036] The first step is to weigh all the prepared raw materials according to their weight and add them into a high-speed mixer, set the speed to 1500r / min and the temperature to 100°C, stir and mix mechanically for 30 minutes, cool and discharge the materials to form a premix;

[0037] The second step is to feed the premixed material into the twin-screw extruder through the feeding port, control the temperature to 220°C, the screw speed to 350r / min, and perform melt extrusion.

[0038] Example 3

[0039] A wear-resistant high-toughness polypropylene material, comprising the following raw materials in parts by weight:

[0040] 85 parts of polypropylene, 15 parts of maleic anhydride grafted polyethylene, 10 parts of ethylene-octene block copolymer, 6.5 parts of mullite functional agent, 1.5 parts of polyethylene wax, 1 part of antioxidant 1010, and 0.4 parts of benzoyl peroxide.

[0041] The preparation method of the polypropylene material comprises the following steps:

[0042] First step: Add the weighed raw materials in parts by weight to a high-speed mixer, set the rotation speed at 2000 r / min and the temperature at 100 °C, mechanically stir and mix for 20 min, then cool down and discharge to form a premix.

[0043] Second step: Feed the premix into a twin-screw extruder through a feeding port, control the temperature at 220 °C and the screw rotation speed at 400 r / min, and carry out melt extrusion.

[0044] The mullite functional agent in the above examples is prepared by the following method:

[0045] Step 1: Add 1 g of 3-glycidoxypropyltriethylsilane to 2 mL of sulfuric acid solution with a pH of 2, stir and mix evenly, then raise the temperature to 100 °C, keep warm for 40 min, then lower the temperature to 40 °C, continue to add 1.5 h of mullite, ultrasonically disperse evenly, then control the temperature at 90 °C, continuously stir for 4 h, cool down and discharge, and obtain activated mullite through a post-treatment process.

[0046] Step 2: Disperse 1.2 g of activated mullite in N,N-dimethylformamide, introduce nitrogen protection, then add 2.5 g of triphenylene-2,6,10-tricarboxylic acid, 0.1 g of 4-dimethylaminopyridine and 0.3 g of dicyclohexylcarbodiimide to the formed dispersion, after adding, mechanically stir evenly, then raise the temperature to 120 °C, keep warm and stir for 6 h, then continue to add 1.6 g of allyl pentaerythritol, after adding, continuously keep warm and stir for 18 h, stop heating, centrifuge to separate out the solid material, and obtain the mullite functional agent through washing and vacuum drying.

[0047] The ester group content of the mullite functional agent was titrated and tested by the soap back titration method, and the result showed that the ester group content was 4.697 mmol / g.

[0048] Comparative Example 1

[0049] A wear-resistant and high-toughness polypropylene material, by weight, comprises the following raw materials:

[0050] 70 parts of polypropylene, 10 parts of maleic anhydride grafted polyethylene, 6 parts of ethylene-octene block copolymer, 6 parts of mullite, 1 part of polyethylene wax, 0.6 part of antioxidant 1010, 0.3 part of benzoyl peroxide.

[0051] The preparation method of the polypropylene material comprises the following steps:

[0052] Step 1: Add each raw material weighed and prepared according to parts by weight into a high-speed mixer. Set the rotation speed to 1500 r / min and the temperature to 100 °C. After mechanically stirring and mixing for 30 min, cool down and discharge to form a premix.

[0053] Step 2: Feed the premix into a twin-screw extruder through the feeding port. Control the temperature at 220 °C and the screw rotation speed at 350 r / min, and perform melt extrusion.

[0054] Example 2

[0055] A wear-resistant and high-toughness polypropylene material, calculated by parts by weight, comprises the following raw materials:

[0056] 70 parts of polypropylene, 10 parts of maleic anhydride grafted polyethylene, 6 parts of ethylene-octene block copolymer, 1 part of polyethylene wax, 0.6 part of antioxidant 1010, and 0.3 part of benzoyl peroxide.

[0057] The preparation method of the polypropylene material comprises the following steps:

[0058] Step 1: Add each raw material weighed and prepared according to parts by weight into a high-speed mixer. Set the rotation speed to 1500 r / min and the temperature to 100 °C. After mechanically stirring and mixing for 30 min, cool down and discharge to form a premix.

[0059] Step 2: Feed the premix into a twin-screw extruder through the feeding port. Control the temperature at 220 °C and the screw rotation speed at 350 r / min, and perform melt extrusion.

[0060] Performance test

[0061] Make each test specimen from the polypropylene materials in the examples and comparative examples, and conduct various performance tests. The results are recorded in the following table:

[0062] Wear amount / g Tensile strength / MPa Elongation at break / % Example 1 0.05 32.6 458.9 Example 2 0.03 33.1 459.7 Example 3 0.04 33.0 459.4 Comparative example 1 0.11 29.9 381.2 Comparative example 2 0.12 23.8 338.5

[0063] The test method for the abrasion loss is as follows: Refer to the standard ASTM D3884. Take a specimen of 10 cm × 10 cm × 8 mm, place it on a grinding and rotating test bench, set the rotation speed to 60 r / min, rub the test specimen, with a load of 1000 g, and select SC10 for the grinding wheel. Test the abrasion loss of the test specimen after 5000 rotations.

[0064] Test the tensile properties of the test specimens according to GB / T 1040.1-2006.

[0065] According to the analysis of the test results, it can be seen that the wear resistance and toughness of the polypropylene material prepared by using unmodified mullite alone as an additive are both poor. This is because there is a compatibility problem between the unmodified mullite and the matrix polypropylene, which cannot efficiently exert its own performance, is difficult to achieve the enhancement and toughening effects, and also cannot utilize the cross-linked network and rigidity brought by the macromolecular polymer, resulting in poor wear resistance of the material.

[0066] In this article, specific examples are used to elaborate on the principle and implementation manner of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention, including the best mode, and also enables any person skilled in the art to practice the present invention, including manufacturing and using any device or system, and implementing any combined method. It should be noted that for those of ordinary skill in the art in the technical field, without departing from the principle of the present invention, several improvements and modifications can be made to the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention. The protection scope of this invention patent is defined by the claims and may include other embodiments that can be conceived by those skilled in the art. If these other embodiments have structural elements similar to the literal description of the claims, or if they include equivalent structural elements that have no substantial difference from the literal description of the claims, then these other embodiments should also be included within the scope of the claims.

[0067] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these 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 various embodiments of the present invention.

Claims

1. A wear-resistant and high-toughness polypropylene material, characterized in that, Comprising the following raw materials by weight parts: 65 - 85 parts of polypropylene, 5 - 15 parts of compatibilizer, 5 - 10 parts of ethylene - octene block copolymer, 2 - 6.5 parts of mullite functional agent, 0.5 - 1.5 parts of lubricant, 0.5 - 1 part of antioxidant, 0.1 - 0.4 part of initiator.

2. The wear-resistant and high-toughness polypropylene material according to claim 1, characterized in that, The compatibilizer is maleic anhydride grafted polyethylene or maleic anhydride grafted polypropylene.

3. The wear-resistant and high-toughness polypropylene material according to claim 1, wherein The mullite functional agent is prepared by the following method: Step 1: Add epoxy group silane coupling agent into sulfuric acid solution, stir and mix evenly, then raise the temperature to 90 - 100 °C, keep warm for 30 - 60 min, then lower the temperature to 40 - 50 °C, continue to add mullite, after ultrasonic dispersion evenly, then control the temperature at 80 - 90 °C, continuously stir for 3 - 6 h, cool down and discharge, through the post - treatment process, activated mullite is obtained; Step 2: Disperse the activated mullite in N,N - dimethylformamide, pass nitrogen for protection, then add triphenylene - 2,6,10 - tricarboxylic acid, catalyst and condensing agent into the formed dispersion liquid, after adding, stir evenly by mechanical stirring, then raise the temperature to 100 - 120 °C, keep warm and stir for 4 - 8 h, then continue to add allyl pentaerythritol, after adding, continuously keep warm and stir for 12 - 24 h, stop heating, centrifuge to separate out the solid material, through washing and vacuum drying treatment, the mullite functional agent can be obtained.

4. The wear-resistant and high-toughness polypropylene material according to claim 3, characterized in that, In Step 1, the epoxy group silane coupling agent is selected from 3 - glycidoxypropyltrimethylsilane or 3 - glycidoxypropyltriethylsilane.

5. The wear-resistant and high-toughness polypropylene material according to claim 3, wherein In Step 1, the pH of the sulfuric acid solution is 2 - 3.

6. The wear-resistant and high-toughness polypropylene material according to claim 3, wherein In Step 2, the catalyst is any one of 4 - dimethylaminopyridine, N - hydroxysuccinimide or 1 - hydroxybenzotriazole.

7. The wear-resistant and high-toughness polypropylene material according to claim 3, wherein In Step 2, the condensing agent is dicyclohexylcarbodiimide or 1 - ethyl - (3 - dimethylaminopropyl) carbodiimide hydrochloride.

8. An abrasion-resistant and high-toughness polypropylene material according to claim 3, characterized in that In Step 2, the mass ratio of the activated mullite, triphenylene - 2,6,10 - tricarboxylic acid and allyl pentaerythritol is 1:1.5 - 2.5:0.8 - 1.

5.

9. A wear-resistant and high-toughness polypropylene material according to claim 1, characterized in that, The lubricant is polyethylene wax or liquid paraffin; the antioxidant is any one of hindered phenol antioxidants or phosphite antioxidants; the initiator is benzoyl peroxide or di - isopropylbenzene peroxide.

10. A method for preparing the wear-resistant and high-toughness polypropylene material according to claim 1, characterized in that, Comprising the following steps: The first step: Add each raw material weighed and prepared according to weight parts into a high - speed mixer, set the rotation speed at 1000 - 2000 r / min and the temperature at 80 - 100 °C, mechanically stir and mix for 20 - 40 min, then cool down and discharge to form a pre - mixture; The second step: Feed the pre - mixture into a twin - screw extruder through a feeding port for melt extrusion.