PP material with scratch resistance and preparation method thereof

Abstract

The invention discloses a PP (polypropylene) material with scratch resistance. The PP material is prepared from the following raw materials in parts by weight: 75-85 parts of a PP matrix; 3 to 8 parts of modified nano silicon dioxide; 5 to 10 parts of an ethylene-octylene copolymer (POE); 2-5 parts of an organosilicon elastomer; 1 to 4 parts of hyperbranched polymer (HBP); 1 to 3 parts of self-repairing microcapsules; 2-5 parts of nano calcium carbonate; 0.3 to 0.8 part of an antioxidant; and 0.5-2 parts of a dispersant. Through the synergistic effect of the modified nano silicon dioxide, the nano calcium carbonate and the hyperbranched polymer (HBP), the surface hardness and the scratch resistance of the PP material are improved, the compatibility of the nano silicon dioxide and the nano calcium carbonate with a PP matrix is enhanced through modification treatment of the nano silicon dioxide and the nano calcium carbonate, and the mechanical property and the wear resistance of the material are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of chemical materials, and in particular to a PP material with scratch-resistant performance and a preparation method thereof. Background Art

[0002] Due to its excellent mechanical properties, chemical resistance and processability, polypropylene (PP) material is widely used in the fields of automotive interiors, household appliance shells, packaging materials, etc. It is light in weight, low in density, resistant to chemical corrosion, good in solvent resistance, moderate in mechanical strength, good in anti-bending fatigue, recyclable and environmentally friendly.

[0003] The surface hardness of traditional PP materials is relatively low and is easily scratched by external forces, affecting its aesthetics and service life. Existing technologies improve the scratch resistance of PP by adding scratch-resistant agents, nano-fillers, etc., but there are still limitations in improving scratch resistance and uneven dispersion of materials. Therefore, it is of great practical significance to develop a PP material with scratch-resistant performance. Summary of the Invention

[0004] In order to solve the above technical deficiencies, the present invention adopts a modified technical solution. A PP material with scratch-resistant performance is composed of the following raw materials in parts by weight:

[0005] Polypropylene (PP) matrix: 75 - 85 parts;

[0006] Modified nano-silica: 3 - 8 parts;

[0007] Ethylene-octene copolymer (POE): 5 - 10 parts;

[0008] Organic silicon elastomer: 2 - 5 parts;

[0009] Hyperbranched polymer (HBP): 1 - 4 parts;

[0010] Self-healing microcapsules: 1 - 3 parts;

[0011] Nano-calcium carbonate: 2 - 5 parts;

[0012] Antioxidant: 0.3 - 0.8 parts;

[0013] Dispersant: 0.5 - 2 parts.

[0014] As a further preferred embodiment of the present invention, it further includes the following amounts of raw materials, wherein polypropylene (PP) matrix: 85 parts; modified nano-silica: 8 parts; ethylene-octene copolymer (POE): 10 parts; organic silicon elastomer: 5 parts; hyperbranched polymer (HBP): 4 parts; self-healing microcapsules: 3 parts; nano-calcium carbonate: 5 parts; antioxidant: 0.8 parts;

[0015] Dispersant: 2 parts.

[0016] As a further preferred embodiment of the present invention, it further includes the following raw material dosages, wherein the polypropylene (PP) matrix: 75 parts; modified nano-silica: 3 parts; ethylene-octene copolymer (POE): 5 parts; silicone elastomer: 2 parts; hyperbranched polymer (HBP): 1 part; self-healing microcapsules: 1 part; nano-calcium carbonate: 2 parts; antioxidant: 0.3 parts;

[0017] Dispersant: 0.2 parts.

[0018] As a further preferred embodiment of the present invention, the self-healing microcapsules are filled with a repair agent, and the repair agent is one or more of epoxy resin, polyurea, polysiloxane or polyurethane to form a mixture, and the wall material of the self-healing microcapsules includes urea-formaldehyde resin, polyurea-formaldehyde resin, polylactic acid, polymethyl methacrylate (PMMA).

[0019] As a further preferred embodiment of the present invention, the hyperbranched polymer (HBP) is one of polyester-based HBP, polyurethane-based HBP, and polyamide-based HBP.

[0020] As a further preferred embodiment of the present invention, it includes the following steps

[0021] S1. Modify the nano-silica and set it aside;

[0022] S2. Modify the nano-calcium carbonate and set it aside;

[0023] S3. According to the formulation ratio, mix PP, modified nano-silica, POE, silicone elastomer, HBP, self-healing microcapsules, nano-calcium carbonate, antioxidant and dispersant, and place them in a mixer to stir evenly;

[0024] S4. Feed the uniformly mixed material into a twin-screw extruder, melt and blend it in the temperature range of 180-230 °C, and make the modified nano-fillers and self-healing microcapsules evenly disperse in the PP matrix through shear action;

[0025] S5. The melt extrudate is cooled, cut into underwater pellets or air-cooled pellets to obtain scratch-resistant PP pellets.

[0026] As a further preferred embodiment of the present invention, the modification treatment of the silica includes the following steps: Take 100 g of nano-silica with a particle size of 20-50 nm, add it to 500 mL of anhydrous ethanol, ultrasonically disperse it for 30 minutes to make the particles evenly dispersed, add 3-5 g of silane coupling agent, stir at 60 °C for 3 hours to promote surface modification, continue stirring, and evaporate the solvent to a dry state, and then dry it in a vacuum oven at 80 °C for 6 hours to obtain modified nano-silica.

[0027] As a further preferred embodiment of the present invention, the modification step of the nano calcium carbonate includes the following: Take 100 g of nano calcium carbonate with a particle size of 50 - 100 nm, add it to 500 mL of deionized water, stir for 30 minutes, add 2 - 3 g of stearic acid, heat up to 70 °C, and continue to stir for 2 hours to allow the stearic acid to be evenly adsorbed on the surface of the calcium carbonate particles. After being treated by high-speed centrifugal separation, it is dried in a vacuum drying oven at 100 °C for 6 hours to obtain surface-modified nano calcium carbonate.

[0028] As a further preferred embodiment of the present invention, in step S3, the stirring temperature is controlled at 45 °C, and the stirring speed is controlled at 250 r / min - 720 r / min.

[0029] Beneficial effects

[0030] Through the synergistic effect of modified nano-silica, nano calcium carbonate, and hyperbranched polymer (HBP), the present invention improves the surface hardness and scratch resistance of the PP material. The modification treatment of nano-silica and nano calcium carbonate enhances their compatibility with the PP matrix, improving the mechanical properties and wear resistance of the material. Self-healing microcapsules are introduced, which are filled with repair agents such as epoxy resin, polyurea, polysiloxane, or polyurethane. When the surface of the material is scratched, the microcapsules rupture, the repair agent flows out and cures, automatically repairing fine scratches and improving the durability of the material. The addition of ethylene-octene copolymer (POE) and silicone elastomer enhances the flexibility of the material and improves the impact resistance, making the material less likely to break or crack when subjected to external forces. The use of modified nano-fillers enhances the dispersibility and mechanical properties of the material. The nano-silica modified with silane coupling agent improves its interfacial bonding force with PP, making it more evenly dispersed in the matrix, reducing the agglomeration phenomenon, and improving the reinforcement effect of the filler. The stearic acid-modified nano calcium carbonate is more evenly dispersed in the PP, enhancing the rigidity and wear resistance of the material, while reducing the energy consumption during the preparation process. Specific embodiments

[0031] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in combination with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts fall within the protection scope of the present invention.

[0032] The present invention provides a technical solution: A PP material with scratch-resistant performance, which is composed of the following raw materials in parts by weight:

[0033] Polypropylene (PP) matrix: 75 - 85 parts;

[0034] Modified nano-silica: 3 - 8 parts;

[0035] Ethylene-octene copolymer (POE): 5-10 parts;

[0036] Silicone elastomer: 2-5 parts;

[0037] Hyperbranched polymer (HBP): 1-4 parts;

[0038] Self-healing microcapsules: 1-3 parts;

[0039] Nano calcium carbonate: 2-5 parts;

[0040] Antioxidant: 0.3-0.8 parts;

[0041] Dispersant: 0.5-2 parts.

[0042] It also includes the following amounts of raw materials, where the polypropylene (PP) matrix: 85 parts; modified nano-silica: 8 parts; ethylene-octene copolymer (POE): 10 parts; silicone elastomer: 5 parts; hyperbranched polymer (HBP): 4 parts; self-healing microcapsules: 3 parts; nano calcium carbonate: 5 parts; antioxidant: 0.8 parts; dispersant: 2 parts.

[0043] It also includes the following amounts of raw materials, where the polypropylene (PP) matrix: 75 parts; modified nano-silica: 3 parts; ethylene-octene copolymer (POE): 5 parts; silicone elastomer: 2 parts; hyperbranched polymer (HBP): 1 part; self-healing microcapsules: 1 part; nano calcium carbonate: 2 parts; antioxidant: 0.3 parts; dispersant: 0.2 parts.

[0044] The self-healing microcapsules are filled with a repair agent, and the repair agent is one or more of epoxy resin, polyurea, polysiloxane or polyurethane to form a mixture. The wall material of the self-healing microcapsules includes urea-formaldehyde resin, polyurea-formaldehyde resin, polylactic acid, polymethyl methacrylate (PMMA). Scratch repair function: When the PP material is scratched, the microcapsules break, releasing the repair agent (such as epoxy resin, polysiloxane, etc.), filling the damaged area, reducing the whitening phenomenon, and improving the scratch resistance. Extend service life: Effectively reduce the accumulation of surface damage and improve the durability of PP products. Maintain the original properties of PP: The microcapsule particles are evenly distributed in the PP matrix, do not affect the overall mechanical properties, and at the same time, the repair rate and effect can be adjusted as needed.

[0045] The hyperbranched polymer (HBP) is one of polyester HBP, polyurethane HBP, and polyamide HBP. It enhances compatibility: improves the uniform dispersion of inorganic fillers (such as nano-silica, calcium carbonate, etc.) in the PP matrix, improves the scratch resistance performance, and improves toughness: the multi-functional group structure of HBP can improve the impact resistance of the material, enabling the material to have good toughness while maintaining high scratch resistance. It reduces the melt viscosity: optimizes the processing fluidity and improves the processing adaptability of the PP material.

[0046] Manufacturing steps: S1. Modify nano-silica and set it aside.

[0047] S2. Modify nano-calcium carbonate and set it aside.

[0048] S3. According to the formulation ratio, mix PP, modified nano-silica, POE, silicone elastomer, HBP, self-healing microcapsules, nano-calcium carbonate, antioxidant, and dispersant, and place them in a mixer to stir evenly.

[0049] S4. Feed the evenly mixed materials into a twin-screw extruder and melt-blend them in the temperature range of 180 - 230 °C. Through the shearing action, make the modified nano-fillers and self-healing microcapsules evenly disperse in the PP matrix.

[0050] S5. The melt-extruded product is cooled and pelletized by underwater pelletizing or air-cooled pelletizing to obtain scratch-resistant PP pellets.

[0051] The modification treatment of silica includes the following steps: Take 100 g of nano-silica with a particle size of 20 - 50 nm, add it to 500 mL of anhydrous ethanol, ultrasonically disperse for 30 minutes to make the particles evenly dispersed, add 3 - 5 g of silane coupling agent, stir at 60 °C for 3 hours to promote surface modification, continue stirring, and evaporate the solvent to a dry state, then dry in a vacuum oven at 80 °C for 6 hours to obtain modified nano-silica.

[0052] The modification steps of nano-calcium carbonate include the following: Take 100 g of nano-calcium carbonate with a particle size of 50 - 100 nm, add it to 500 mL of deionized water, stir for 30 minutes, add 2 - 3 g of stearic acid, heat to 70 °C, and continue stirring for 2 hours to make stearic acid evenly adsorbed on the surface of calcium carbonate particles. After high-speed centrifugal separation, dry in a vacuum drying oven at 100 °C for 6 hours to obtain surface-modified nano-calcium carbonate.

[0053] In step S3, the stirring temperature is controlled at 45 °C, and the stirring speed is controlled at 250 r / min - 720 r / min.

[0054] Example 1:

[0055] Polypropylene (PP) matrix: 85 parts; modified nano-silica: 8 parts; ethylene-octene copolymer (POE): 10 parts; silicone elastomer: 5 parts; hyperbranched polymer (HBP): 4 parts; self-healing microcapsules: 3 parts; nano-calcium carbonate: 5 parts; antioxidant: 0.8 parts; dispersant: 2 parts. Modify the nano-silica and set it aside; modify the nano-calcium carbonate and set it aside; according to the formulation ratio, mix PP, modified nano-silica, POE, silicone elastomer, HBP, self-healing microcapsules, nano-calcium carbonate, antioxidant and dispersant, place them in a mixer and stir evenly. The stirring temperature is controlled at 45 °C and the stirring speed is controlled at 720 r / min; feed the evenly mixed material into a twin-screw extruder and melt-blend it in the temperature range of 230 °C. Through the shearing action, the modified nano-fillers and self-healing microcapsules are evenly dispersed in the PP matrix; the melt-extruded product is cooled and pelletized by underwater pelletizing or air-cooled pelletizing to obtain scratch-resistant PP pellets.

[0056] Example 2:

[0057] Polypropylene (PP) matrix: 75 parts; modified nano-silica: 3 parts; ethylene-octene copolymer (POE): 5 parts; silicone elastomer: 2 parts; hyperbranched polymer (HBP): 1 part; self-healing microcapsules: 1 part; nano-calcium carbonate: 2 parts; antioxidant: 0.3 parts; dispersant: 0.2 parts.

[0058] Modify the nano-silica and set it aside; modify the nano-calcium carbonate and set it aside; according to the formulation ratio, mix PP, modified nano-silica, POE, silicone elastomer, HBP, self-healing microcapsules, nano-calcium carbonate, antioxidant and dispersant, place them in a mixer and stir evenly. The stirring temperature is controlled at 45 °C and the stirring speed is controlled at 250 r / min; feed the evenly mixed material into a twin-screw extruder and melt-blend it in the temperature range of 180 °C. Through the shearing action, the modified nano-fillers and self-healing microcapsules are evenly dispersed in the PP matrix; the melt-extruded product is cooled and pelletized by underwater pelletizing or air-cooled pelletizing to obtain scratch-resistant PP pellets.

[0059] The above shows and describes the basic principles, main features and advantages of the present invention. For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and without departing from the spirit or basic features of the present invention, the present invention can be implemented in other specific forms. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, it is intended to include all changes falling within the meaning and scope of the equivalent elements of the claims in the present invention.

[0060] In addition, it should be understood that although this specification is described according to embodiments, not every embodiment only contains an independent technical solution. This narrative way of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A PP material with scratch-resistant performance, characterized in that: It consists of the following raw materials in parts by weight: Polypropylene (PP) matrix: 75 - 85 parts; Modified nano-silica: 3 - 8 parts; Ethylene-octene copolymer (POE): 5 - 10 parts; Silicone elastomer: 2 - 5 parts; Hyperbranched polymer (HBP): 1 - 4 parts; Self-healing microcapsules: 1 - 3 parts; Nano-calcium carbonate: 2 - 5 parts; Antioxidant: 0.3 - 0.8 parts; Dispersant: 0.5 - 2 parts.

2. The PP material with scratch resistance according to claim 1, characterized in that, It also includes the following amounts of raw materials, where polypropylene (PP) matrix: 85 parts; modified nano-silica: 8 parts; ethylene-octene copolymer (POE): 10 parts; silicone elastomer: 5 parts; hyperbranched polymer (HBP): 4 parts; self-healing microcapsules: 3 parts; nano-calcium carbonate: 5 parts; antioxidant: 0.8 parts; dispersant: 2 parts.

3. A PP material with scratch resistance according to claim 1, characterized in that, It also includes the following amounts of raw materials, where polypropylene (PP) matrix: 75 parts; modified nano-silica: 3 parts; ethylene-octene copolymer (POE): 5 parts; silicone elastomer: 2 parts; hyperbranched polymer (HBP): 1 part; self-healing microcapsules: 1 part; nano-calcium carbonate: 2 parts; antioxidant: 0.3 parts; Dispersant: 0.2 parts.

4. A PP material with scratch resistance according to claim 1, characterized in that, The interior of the self-healing microcapsules is filled with a repair agent, and the repair agent is one or more of epoxy resin, polyurea, polysiloxane or polyurethane to form a mixture. The wall material of the self-healing microcapsules includes urea-formaldehyde resin, polyurea-formaldehyde resin, polylactic acid, polymethyl methacrylate (PMMA).

5. The PP material with scratch resistance according to claim 1 is characterized in that, The hyperbranched polymer (HBP) is one of polyester-based HBP, polyurethane-based HBP, and polyamide-based HBP.

6. The preparation method of a PP material with scratch resistance according to claim 1, characterized in that, It includes the following steps S1. Modify the nano-silica and set it aside; S2. Modify the nano-calcium carbonate and set it aside; S3. According to the formula ratio, mix PP, modified nano-silica, POE, silicone elastomer, HBP, self-healing microcapsules, nano-calcium carbonate, antioxidant and dispersant, and place them in a mixer to stir evenly; S4. Feed the evenly mixed material into a twin-screw extruder and melt-blend it in the temperature range of 180 - 230 °C. Through shear action, the modified nano-fillers and self-healing microcapsules are evenly dispersed in the PP matrix; S5. The melt-extruded product is cooled and pelletized by underwater pelletizing or air-cooled pelletizing to obtain scratch-resistant PP pellets.

7. The preparation method of a PP material with scratch resistance according to claim 6, characterized in that, The modification treatment of the silica includes the following steps. Take 100 g of nano-silica with a particle size of 20 - 50 nm, add it to 500 mL of absolute ethanol, and ultrasonically disperse it for 30 minutes to make the particles evenly dispersed. Add 3 - 5 g of silane coupling agent, stir at 60 °C for 3 hours to promote surface modification, continue stirring, and evaporate the solvent to a dry state, and then dry it in a vacuum oven at 80 °C for 6 hours to obtain modified nano-silica.

8. The preparation method of a PP material with scratch resistance according to claim 6, characterized in that, The modification steps of the nano calcium carbonate are as follows: Take 100 g of nano calcium carbonate with a particle size of 50 - 100 nm, add it to 500 mL of deionized water, stir for 30 minutes, add 2 - 3 g of stearic acid, raise the temperature to 70 °C, and continue stirring for 2 hours to allow the stearic acid to be evenly adsorbed on the surface of the calcium carbonate particles. After being treated by high-speed centrifugal separation, it is dried in a vacuum drying oven at 100 °C for 6 hours to obtain surface-modified nano calcium carbonate.

9. The preparation method of a PP material with scratch resistance according to claim 6, characterized in that, In step S3, the stirring temperature is controlled at 45 °C, and the stirring speed is controlled at 250 r / min - 720 r / min.