High-strength and high-toughness PP material and preparation method thereof

Abstract

The invention relates to the technical field of materials, and discloses a high-strength and high-toughness PP material and a preparation method thereof.The PP material is prepared by taking polypropylene as a base material and diamond fiber reinforced modified materials and the like as additives through mixing and extrusion processes. Wherein the diamond fiber reinforced modified material is prepared by modifying the surface of diamond fiber with a polymer modifier in which fluorene and rubber are alternately connected, and the diamond fiber can exist in the material in a physical crosslinking core form, so that the tensile strength of polypropylene is greatly enhanced; a rigid fluorene ring in the macromolecular modifier can effectively enhance the stability of the polypropylene material, so that the polypropylene material shows more excellent impact strength, and a polysulfide rubber molecular chain can make the flexibility of a network structure higher by utilizing the high flexibility of the polysulfide rubber molecular chain, so that the toughness of the polypropylene material is effectively improved.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of materials, in particular to a high-strength and high-toughness PP material and a preparation method thereof. BACKGROUND

[0002] Polypropylene (PP) is one of the five general-purpose plastics, and is gradually selected as a daily-use plastic due to the characteristics of non-toxicity, chemical corrosion resistance, low density and excellent processing performance. However, the molecular chain structure of polypropylene has inherent defects, that is, the strength and toughness are poor, which greatly limits the application of polypropylene in the field of daily-use plastics. Therefore, it is necessary to modify the polypropylene material to meet the use requirements of high-strength and high-toughness daily-use plastic products.

[0003] Nanotechnology is one of the important ways for the modification of polypropylene. By blending inorganic nanomaterials with polypropylene, the inorganic nanomaterials can be used to modify the polypropylene by utilizing the high strength of the inorganic nanomaterials. However, there is a natural interface problem between the inorganic materials and the high polymer materials, and the poor interface compatibility between them will cause the inorganic materials to agglomerate, and a large amount of inorganic materials need to be added to achieve the purpose of strengthening. However, a large amount of addition will have a great negative impact on the modification of the material. Based on this, the application provides a polypropylene composite material, which can solve the problems in the prior art. SUMMARY

[0004] In order to solve the problems mentioned in the background art, the purpose of the application is to provide a high-strength and high-toughness PP material and a preparation method thereof.

[0005] The purpose of the application can be achieved by the following technical solutions.

[0006] A high-strength and high-toughness PP material comprises the following raw materials in parts by weight:

[0007]

[0008] As a further scheme of the application, the diamond fiber reinforced modified material is prepared by the following method:

[0009] Step one, disperse the diamond fiber in an ethanol aqueous solution, then add a surface modifier to the formed uniform dispersion liquid, after the addition is completed, adjust the pH to 3-4, then increase the temperature to 60-70 DEG C, stir for 4-8 h, stop heating, cool down, centrifuge the solid, wash, vacuum dry, and prepare the surface modified diamond fiber;

[0010] Step two, the surface modified diamond fiber is added into dimethyl sulfoxide, and ultrasonic dispersion is carried out to form a uniform dispersion liquid, then phenyl ether fluorene and an aqueous solution of alkaline hydroxide are added into the dispersion liquid, after addition, nitrogen is introduced for protection, after stirring and mixing uniformly, the temperature is increased to 70-80℃, and after continuous incubation for 2-3h, the rubber connecting agent is added into the dispersion liquid, and the temperature is further increased to 90-100℃, and after continuous stirring for 9-18h, the heating is stopped, the temperature is lowered, the product is collected, and the diamond fiber reinforced modified material is obtained.

[0011] As a further scheme of the present application, the surface modifier is 3-bromopropyl trimethoxysilane or 3-bromopropyl triethoxysilane.

[0012] As a further scheme of the present application, the alkaline hydroxide is potassium hydroxide or sodium hydroxide.

[0013] As a further scheme of the present application, the mass fraction of the aqueous solution of alkaline hydroxide is 10-30%.

[0014] As a further scheme of the present application, the rubber connecting agent is prepared by the following method:

[0015] Liquid polysulfide rubber and dimethylbenzene are added into a nitrogen-filled reaction kettle, after addition, stirring is started, and after a uniform mixture is formed, bromoacetyl chloride and triethylamine are added into the mixture, after addition, stirring is uniform, then mechanical stirring is carried out at a temperature of 30-40℃ for 3-6h, then the solvent is removed by distillation under reduced pressure, the product is collected, and after purification treatment, the rubber connecting agent is obtained.

[0016] As a further scheme of the present application, the number average molecular weight of the liquid polysulfide rubber is 1000-1600.

[0017] As a further scheme of the present application, the molar ratio of the liquid polysulfide rubber and bromoacetyl chloride is 1:2.

[0018] In the above technical scheme, first, the surface of the diamond fiber is modified by using a surface modifier, so that the diamond fiber surface can carry a halogen substituent, and the surface modified diamond fiber is prepared, then under the catalysis of alkaline hydroxide, the halogen substituent can be substituted with the active hydroxyl substituent in the structure of phenyl ether fluorene, and the remaining amount of phenyl ether fluorene in the system can act as a bridging agent to continuously and uninterruptedly substitute the halogen substituent at the end of the rubber connecting agent structure, thereby producing the effect of initiating in-situ polymerization of phenyl ether fluorene and rubber connecting agent on the surface of the diamond fiber with the halogen substituent of the surface modified diamond fiber as the active initiation site, thereby modifying the fluorene-rubber alternating connected high molecular modifier on the surface of the diamond fiber, and preparing the diamond fiber reinforced modified material.

[0019] The rubber binder is prepared by condensing the terminal thiol groups and acyl halide groups in the structure of liquid polysulfide rubber and bromoacetyl chloride as raw materials. By controlling the ratio of the two, the rubber binder can be made to exhibit bromine-terminated behavior.

[0020] As a further aspect of the present invention, the compatibilizer is any one of maleic anhydride-grafted polypropylene, maleic anhydride-grafted polyethylene, or maleic anhydride-grafted ethylene-octene copolymer; the antioxidant is at least one of antioxidant 1010 or antioxidant 1076; the filler is any one of fumed silica, talc, calcium carbonate, or titanium dioxide; and the lubricant is polyethylene wax or zinc stearate.

[0021] A method for preparing a high-strength and high-toughness PP material includes the following steps:

[0022] Step 1: Weigh all the ingredients according to the specified weight proportions, add them to the mixer, control the speed to 1000-1500 r / min, and mechanically mix for 1-2 hours to obtain a uniform mixture.

[0023] The second step is to transfer the mixture to a twin-screw extruder, control the temperature at 200-240℃ and the screw speed at 300-500 r / min, and perform melt extrusion granulation.

[0024] The beneficial effects of this invention are:

[0025] This invention prepares a diamond fiber reinforced modified material by modifying the surface of diamond fibers with a polymeric modifier that alternates between fluorene and rubber. It should be noted that when mixed with polypropylene, the presence of the polymeric modifier creates a transition between the diamond fibers and polypropylene. During subsequent melt extrusion, the polymeric modifier molecular chains intertwine with the polypropylene molecular chains, forming a network structure. This allows the diamond fibers to exist in the material as physical cross-linked cores, thus fully utilizing their tensile and stress absorption effects to significantly enhance the tensile strength of the polypropylene. Furthermore, the rigid fluorene rings in the polymeric modifier effectively enhance the stability of the polypropylene material, resulting in superior impact strength, while the high flexibility of the polysulfide rubber molecular chains further improves the network structure's toughness, effectively enhancing the toughness of the polypropylene material.

[0026] Of course, any product implementing this invention does not necessarily need to achieve all of the advantages described above at the same time. Detailed Implementation

[0027] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] Example 1

[0029] A high-strength and high-toughness PP material, comprising the following raw materials in parts by weight:

[0030]

[0031] The preparation method of the PP material includes the following steps:

[0032] Step 1: Weigh all the ingredients according to the specified weight proportions, add them to the mixer, control the speed to 1000 r / min, and mechanically mix for 2 hours to obtain a uniform mixture.

[0033] The second step is to transfer the mixture to a twin-screw extruder, control the temperature at 220℃ and the screw speed at 400r / min, and perform melt extrusion granulation.

[0034] The diamond fiber reinforced modified material is prepared using the following method:

[0035] Step 1: Disperse 2.6g of diamond fiber in an ethanol aqueous solution, then add 1.5g of 3-bromopropyltriethoxysilane to the formed uniform dispersion. After the addition is complete, adjust the pH to 4, then raise the temperature to 65℃, stir for 6 hours, stop heating, cool down and discharge the material, centrifuge to remove the solid, wash and vacuum dry to obtain surface-modified diamond fiber.

[0036] Step 2: Add 1.8g of surface-modified diamond fiber to dimethyl sulfoxide and ultrasonically disperse until a uniform dispersion is formed. Then, add 2.5g of phenyl diether fluorene and 5mL of 20% (w / w) alkaline hydroxide aqueous solution to the dispersion. After the addition is complete, purge with nitrogen for protection, stir and mix evenly, raise the temperature to 75℃ and keep it at that temperature for 3 hours. Then, add 1.5g of rubber binder to the dispersion and raise the temperature further to 90℃. Continue stirring for 16 hours, then stop heating, cool down and discharge the material, collect the product, and obtain the diamond fiber reinforced modified material.

[0037] The rubber binder is prepared using the following method:

[0038] 2.5g of liquid polysulfide rubber with a number average molecular weight of 1000 and xylene were added to a nitrogen-filled reactor. After the addition was complete, stirring was started. After a homogeneous mixture was formed, 0.8g of bromoacetyl chloride and 0.1g of triethylamine were added to the mixture. After the addition was complete, the mixture was stirred evenly. Then, the mixture was mechanically stirred at 35°C for 4 hours. The solvent was removed by vacuum distillation, the product was collected, and the rubber binder was obtained through purification.

[0039] Example 2

[0040] A high-strength and high-toughness PP material, comprising the following raw materials in parts by weight:

[0041]

[0042]

[0043] The preparation method of the PP material includes the following steps:

[0044] Step 1: Weigh all the ingredients according to the specified weight proportions, add them to the mixer, control the speed to 1200 r / min, and mechanically mix for 2 hours to obtain a uniform mixture.

[0045] The second step is to transfer the mixture to a twin-screw extruder, control the temperature at 220℃ and the screw speed at 400r / min, and perform melt extrusion granulation.

[0046] The preparation method of the diamond fiber reinforced modified material is the same as that in Example 1.

[0047] Example 3

[0048] A high-strength and high-toughness PP material, comprising the following raw materials in parts by weight:

[0049]

[0050] The preparation method of the PP material includes the following steps:

[0051] Step 1: Weigh all the ingredients according to the specified weight proportions, add them to the mixer, control the speed to 1500 r / min, and mechanically mix for 1 hour to obtain a uniform mixture.

[0052] The second step is to transfer the mixture to a twin-screw extruder, control the temperature at 220℃ and the screw speed at 400r / min, and perform melt extrusion granulation.

[0053] The preparation method of the diamond fiber reinforced modified material is the same as that in Example 1.

[0054] Comparative Example 1

[0055] A high-strength and high-toughness PP material, comprising the following raw materials in parts by weight:

[0056]

[0057] The preparation method of the PP material includes the following steps:

[0058] Step 1: Weigh all the ingredients according to the specified weight proportions, add them to the mixer, control the speed to 1200 r / min, and mechanically mix for 2 hours to obtain a uniform mixture.

[0059] The second step is to transfer the mixture to a twin-screw extruder, control the temperature at 220℃ and the screw speed at 400r / min, and perform melt extrusion granulation.

[0060] Comparative Example 2

[0061] A high-strength and high-toughness PP material, comprising the following raw materials in parts by weight:

[0062]

[0063] The preparation method of the PP material includes the following steps:

[0064] Step 1: Weigh all the ingredients according to the specified weight proportions, add them to the mixer, control the speed to 1200 r / min, and mechanically mix for 2 hours to obtain a uniform mixture.

[0065] The second step is to transfer the mixture to a twin-screw extruder, control the temperature at 220℃ and the screw speed at 400r / min, and perform melt extrusion granulation.

[0066] Performance testing

[0067] The PP materials used in the examples and comparative examples were made into test strips that met various specifications, and various performance tests were conducted.

[0068] Tensile properties were tested according to standard GB / T 1040.1-2006;

[0069] Impact performance testing was conducted according to standard GB / T 1843-2008;

[0070] The test results are recorded in Table 1:

[0071] Tensile strength / MPa Elongation at break / % Impact strength / kJ / m 2 ]] Example 1 36.4 68.1 28.6 Example 2 36.9 68.7 29.0 Example 3 36.7 68.3 28.9 Comparative Example 1 32.1 59.4 25.2 Comparative Example 2 25.7 48.0 20.8

[0072] Analysis of the test results shows that the material prepared in the embodiments of the present invention has significantly better performance in all aspects. After replacing the diamond fiber reinforced material with diamond fiber, there is an obvious interfacial incompatibility problem between the diamond fiber and the polypropylene matrix due to the lack of surface modification. This results in the material being unable to fully exert its reinforcing advantages, leading to a significant decrease in strength. At the same time, the toughening effect of the polysulfide rubber molecular chain is lost, and the toughness of the material is also significantly reduced.

[0073] This document uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of these embodiments are merely to aid in understanding the method and core ideas of the present invention, including the best mode, and to enable 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 those skilled in the art can make various improvements and modifications to the present invention without departing from its principles, and these improvements and modifications also fall within the scope of protection of the claims. The scope of protection of this 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 those expressed in the claims, or if they include equivalent structural elements that are not substantially different from those expressed in the claims, then these other embodiments should also be included within the scope of the claims.

[0074] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions 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-strength and high-toughness PP material, characterized in that, Includes the following raw materials by weight:

2. The high-strength and high-toughness PP material according to claim 1, characterized in that, The diamond fiber reinforced modified material is prepared by the following method: Step 1: Disperse diamond fibers in an ethanol aqueous solution, then add a surface modifier to the formed uniform dispersion. After the addition is complete, adjust the pH to 3-4, then raise the temperature to 60-70℃, stir for 4-8 hours, stop heating, cool down and discharge the material, centrifuge to remove the solids, wash and vacuum dry to obtain surface-modified diamond fibers. Step 2: Add the surface-modified diamond fibers to dimethyl sulfoxide and ultrasonically disperse until a uniform dispersion is formed. Then, add phenyl diether fluorene and an alkaline hydroxide aqueous solution to the dispersion. After the addition is complete, purge with nitrogen for protection and stir until uniformly mixed. Raise the temperature to 70-80℃ and maintain the temperature for 2-3 hours. Then, add the rubber binder to the dispersion and further raise the temperature to 90-100℃. Continue stirring for 9-18 hours, then stop heating, cool down and discharge the material. Collect the product to obtain the diamond fiber reinforced modified material.

3. The high-strength and high-toughness PP material according to claim 2, characterized in that, The surface modifier is 3-bromopropyltrimethoxysilane or 3-bromopropyltriethoxysilane.

4. The high-strength and high-toughness PP material according to claim 2, characterized in that, The alkaline hydroxide is potassium hydroxide or sodium hydroxide.

5. The high-strength and high-toughness PP material according to claim 2, characterized in that, The mass fraction of the alkaline hydroxide aqueous solution is 10-30%.

6. The high-strength and high-toughness PP material according to claim 2, characterized in that, The rubber binder is prepared using the following method: Liquid polysulfide rubber and xylene are added to a nitrogen-filled reactor. After the addition is complete, stirring is started. Once a homogeneous mixture is formed, bromoacetyl chloride and triethylamine are added to the mixture. After the addition is complete, the mixture is stirred evenly. Then, the mixture is mechanically stirred at 30-40℃ for 3-6 hours. The solvent is removed by vacuum distillation, the product is collected, and the rubber binder is obtained through purification.

7. The high-strength and high-toughness PP material according to claim 6, characterized in that, The number average molecular weight of the liquid polysulfide rubber is 1000-1600.

8. The high-strength and high-toughness PP material according to claim 6, characterized in that, The molar ratio of the liquid polysulfide rubber to bromoacetyl chloride is 1:

2.

9. The high-strength and high-toughness PP material according to claim 1, characterized in that, The compatibilizer is any one of maleic anhydride-grafted polypropylene, maleic anhydride-grafted polyethylene, or maleic anhydride-grafted ethylene-octene copolymer; the antioxidant is at least one of antioxidant 1010 or antioxidant 1076; the filler is any one of fumed silica, talc, calcium carbonate, or titanium dioxide; and the lubricant is polyethylene wax or zinc stearate.

10. A method for preparing the high-strength and high-toughness PP material as described in claim 1, characterized in that, Includes the following steps: Step 1: Weigh all the ingredients according to the specified weight proportions, add them to the mixer, control the speed to 1000-1500 r / min, and mechanically mix for 1-2 hours to obtain a uniform mixture. The second step is to transfer the mixture to a twin-screw extruder, control the temperature at 200-240℃ and the screw speed at 300-500 r / min, and perform melt extrusion granulation.

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