White high light-shielding polypropylene material and preparation method thereof
By using modified calcite and wollastonite as light-shielding additives, the problem of insufficient light-shielding performance of white polypropylene pipe fittings was solved, achieving improved light-shielding performance and mechanical strength, and reducing production costs.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- WUHAN CENTURY JINNIU PIPE FITTING TECH CO LTD
- Filing Date
- 2023-11-29
- Publication Date
- 2026-06-09
AI Technical Summary
The existing white polypropylene pipe fittings have insufficient light-shielding performance, resulting in high light transmittance, which makes them prone to algae and bacteria growth. In addition, commonly used light-shielding additives such as titanium dioxide and mica powder are expensive and have poor dispersibility, affecting processing performance and mechanical properties.
Surface-modified calcite and wollastonite were used as light-shielding agents. Through stearic acid modification, combined with dispersants and antioxidants, white high-light-shielding polypropylene materials were prepared. Modified calcite and modified wollastonite were used to replace traditional high-cost titanium dioxide and mica powder.
It significantly improves the light-blocking and mechanical properties of polypropylene materials, reduces costs, and meets the requirements for light-blocking and mechanical properties, conforming to industry standards.
Smart Images
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Abstract
Description
Technical Field
[0001] This invention relates to the field of polypropylene materials technology, specifically to a white, high-opacity polypropylene material and its preparation method. Background Technology
[0002] Polypropylene (PP) has a wide range of applications in home appliances, sanitary ware, and electronics due to its advantages such as being non-toxic, low-odor, low-cost, chemically resistant, and having good mechanical properties. Currently, PP pipe fittings on the market are available in a variety of colors, including green, white, gray, blue, yellow, and red. With the increase in colors, the composition of the masterbatch used to prepare the pipe body varies greatly. For example, white pipes have a higher content of light-blocking components compared to green pipes, and different pigment ratios also result in variations.
[0003] There are strict requirements for the light-shielding performance of polypropylene pipe fittings both domestically and internationally. For example, ISO 15874-2:2003 and GB / T18742.3-2017 standards clearly require that the light transmittance of pipe fitting products should not exceed 0.2%. In order to meet this requirement, most manufacturers choose to produce dark-colored products such as gray and green. However, in some cases, such as when the pipes are installed in the open, white polypropylene pipe fittings are required. Because white products have the problem of light transmission, algae and bacteria can easily grow inside the pipes, which can be harmful to human health.
[0004] Currently, titanium dioxide and mica powder are commonly used additives to improve the light-shielding performance of polypropylene pipe fittings. However, titanium dioxide and mica powder are relatively expensive. If the amount added is small, the hiding power is insufficient. If the amount added is large, the cost is high. In addition, the poor dispersibility of titanium dioxide and mica powder will affect the processing performance of PP pipe fittings and also reduce the mechanical properties and low-temperature resistance of PP pipe fittings. Summary of the Invention
[0005] To address the problems existing in the prior art, the present invention provides a white high-opacity polypropylene material and its preparation method. This polypropylene material has good light-blocking and mechanical properties, and other properties meet the requirements of industry or national standards.
[0006] The technical solution adopted to achieve the above-mentioned objectives of this invention is as follows:
[0007] A white, high-light-blocking polypropylene material is prepared from the following raw materials in parts by weight:
[0008]
[0009]
[0010] The modified calcite is surface-modified calcite, and the modified wollastonite is surface-modified alumina-coated wollastonite.
[0011] Furthermore, the preparation method of the modified calcite is as follows:
[0012] Add calcite powder to a high-speed mixer and heat to 90-110℃. Add stearic acid, the mass of which is 0.8-1.5% of the mass of the calcite powder. Stir and modify at 90-110℃ for 15-20 minutes to obtain modified calcite.
[0013] Furthermore, the preparation method of the modified wollastonite is as follows:
[0014] Wollastonite powder was added to water to prepare a wollastonite dispersion. Aluminum sulfate solution was added to the wollastonite dispersion and mixed evenly. The pH was adjusted to 5-6 and reacted at 70-90℃ for 0.5-1.5 hours. After washing with water and drying, alumina-coated wollastonite was obtained.
[0015] Add alumina-coated wollastonite to a high-speed mixer and heat to 90-110℃. Add stearic acid, the mass of which is 0.8-1.5% of the mass of alumina-coated wollastonite. Stir and modify at 90-110℃ for 15-20 minutes to obtain modified wollastonite.
[0016] Furthermore, the dispersant is maleic anhydride-grafted polypropylene wax or polypropylene wax.
[0017] Furthermore, the antioxidant is selected from at least one of antioxidant 1010, antioxidant 168 and antioxidant 1076.
[0018] A method for preparing the white, high-opacity polypropylene material according to claim 1, characterized by comprising the following steps:
[0019] S1. Add polypropylene resin, modified calcite, modified wollastonite, dispersant and antioxidant to a mixer and mix at high speed.
[0020] S2. The mixture is added to a twin-screw extruder for extrusion granulation to obtain the composite antistatic polypropylene material.
[0021] Compared with the prior art, the advantages and beneficial effects of the present invention are as follows:
[0022] 1. This invention uses modified calcite and modified wollastonite as light-shielding additives, which can not only improve the light-shielding performance of polypropylene materials, but also greatly reduce costs due to the low price of calcite and wollastonite.
[0023] 2. This invention uses modified calcite and modified wollastonite as light-shielding agents to improve the mechanical strength of polypropylene materials.
[0024] 3. This invention uses stearic acid to modify the surface of calcite and wollastonite, which can improve the light-blocking performance and mechanical properties of polypropylene materials compared to other surface modifiers. Detailed Implementation
[0025] The present invention will now be described in detail with reference to specific embodiments, but these embodiments are not to be construed as limiting the scope of protection of the present invention in any sense.
[0026] The modified calcite is prepared as follows:
[0027] 100 parts by weight of calcite powder were added to a high-speed mixing pot with a rotation speed of 800 r / min, heated to 100℃, 1 part by weight of stearic acid was added, and the mixture was stirred and modified at 100℃ for 20 min to obtain modified calcite.
[0028] The modified wollastonite is prepared as follows:
[0029] 100 parts by weight of wollastonite powder were added to water to prepare a wollastonite dispersion with a mass fraction of 30%. Aluminum sulfate solution (10 parts by weight of aluminum sulfate) was added to the wollastonite dispersion, mixed evenly, and the pH was adjusted to 5.5. The mixture was reacted at 80°C for 1 hour. After washing with water and drying, alumina-coated wollastonite was obtained.
[0030] 100 parts by mass of alumina-coated wollastonite were added to a high-speed mixing pot with a rotation speed of 800 r / min, heated to 100℃, 1 part by mass of stearic acid was added, and the mixture was stirred at 100℃ for 20 min to obtain modified wollastonite.
[0031] The modified calcite and modified wollastonite used in the following examples and comparative examples were all prepared according to the above method.
[0032] Example 1
[0033] A white, high-light-blocking polypropylene material is prepared from the following raw materials in parts by weight:
[0034]
[0035] The preparation method of the above-mentioned white high-opacity polypropylene material is as follows:
[0036] 1. Add polypropylene resin, modified calcite, modified wollastonite, maleic anhydride grafted polypropylene wax and antioxidant 1010 to the mixing pot, control the speed of the mixing pot to 900 r / min, and mix evenly.
[0037] 2. Add the mixture to a twin-screw extruder and extrude and granulate at 180°C to obtain the white high-opacity polypropylene material.
[0038] Example 2
[0039] A white, high-light-blocking polypropylene material is prepared from the following raw materials in parts by weight:
[0040]
[0041]
[0042] The preparation method of the above-mentioned white high-opacity polypropylene material is as follows:
[0043] 1. Add polypropylene resin, modified calcite, modified wollastonite, maleic anhydride grafted polypropylene wax and antioxidant 1010 to the mixing pot, control the speed of the mixing pot to 900 r / min, and mix evenly.
[0044] 2. Add the mixture to a twin-screw extruder and extrude and granulate at 180°C to obtain the white high-opacity polypropylene material.
[0045] Comparative Example 1
[0046] A white polypropylene material, prepared from the following raw materials in parts by weight:
[0047]
[0048] The preparation method of the above-mentioned white high-opacity polypropylene material is as follows:
[0049] 1. Add polypropylene resin, modified calcite, maleic anhydride grafted polypropylene wax and antioxidant 1010 to the mixing pot, control the speed of the mixing pot to 900 r / min, and mix evenly.
[0050] 2. Add the mixture to a twin-screw extruder and extrude and granulate at 180°C to obtain the white high-opacity polypropylene material.
[0051] Comparative Example 2
[0052] A white polypropylene material, prepared from the following raw materials in parts by weight:
[0053]
[0054] The preparation method of the above-mentioned white high-opacity polypropylene material is as follows:
[0055] 1. Add polypropylene resin, modified wollastonite, maleic anhydride grafted polypropylene wax and antioxidant 1010 to the mixing pot, control the speed of the mixing pot to 900 r / min, and mix evenly.
[0056] 2. Add the mixture to a twin-screw extruder and granulate it at 180°C to obtain the white high-opacity polypropylene material.
[0057] Comparative Example 3
[0058] A white polypropylene material, prepared from the following raw materials in parts by weight:
[0059] 100 parts of polypropylene resin
[0060] 1.5 parts maleic anhydride-grafted polypropylene wax
[0061] Antioxidant 1010 0.8 parts;
[0062] The preparation method of the above-mentioned white polypropylene material is as follows:
[0063] 1. Add polypropylene resin, modified wollastonite, maleic anhydride grafted polypropylene wax and antioxidant 1010 to the mixing pot, control the speed of the mixing pot to 900 r / min, and mix evenly.
[0064] 2. Add the mixture to a twin-screw extruder and granulate it at 180°C to obtain the white high-opacity polypropylene material.
[0065] Comparative Example 4
[0066] The difference from Example 1 is that the surface modifier is changed from stearic acid to isopropyl dioleoyloxy (dioctyl phosphate oxy).
[0067] Comparative Example 5
[0068] The difference from Example 1 is that the surface modifier is changed from stearic acid to γ-methacryloyloxypropyltrimethoxysilane.
[0069] The white high-opacity polypropylene materials prepared in Examples 1-2 and the white polypropylene materials prepared in Comparative Examples 1-5 were tested. The transmittance, tensile strength, and flexural modulus of the white polypropylene materials were tested. Transmittance was tested according to standard GB / T 21300-2007 "Determination of Opacity of Plastic Pipes and Fittings," tensile strength was tested according to standard GB / T1040-1992 "Plastics - Tensile Testing Method," and flexural modulus was tested according to GB / T 9341-2008 "Determination of Flexural Properties of Plastics."
[0070] The test results are shown in Table 1 below:
[0071] Table 1 Comparison of the properties of white polypropylene materials with different formulations
[0072]
[0073] As shown in the table above, when modified calcite and modified wollastonite are used as light-blocking additives, the light-blocking performance of polypropylene materials can be significantly improved, and their mechanical properties can also be enhanced.
Claims
1. A white, high-light-blocking polypropylene material, characterized in that... It is prepared from the following raw materials in parts by weight: 100 parts of polypropylene resin 6-12 parts of modified calcite 5-8 parts of modified wollastonite 1-2 parts of dispersant Antioxidant 0.5-1 part; The modified calcite is surface-modified calcite, and the modified wollastonite is surface-modified alumina-coated wollastonite; The modified calcite is prepared as follows: Add calcite powder to a high-speed mixer, heat to 90-110℃, add stearic acid (0.8-1.5% of the mass of calcite powder), stir at 90-110℃ for 15-20 minutes to modify, and obtain modified calcite. The modified wollastonite is prepared as follows: Wollastonite powder was added to water to prepare a wollastonite dispersion. Aluminum sulfate solution was added to the wollastonite dispersion and mixed evenly. The pH was adjusted to 5-6 and reacted at 70-90℃ for 0.5-1.5 hours. After washing with water and drying, alumina-coated wollastonite was obtained. Add alumina-coated wollastonite to a high-speed mixer and heat to 90-110℃. Add stearic acid, the mass of which is 0.8-1.5% of the mass of alumina-coated wollastonite. Stir and modify at 90-110℃ for 15-20 minutes to obtain modified wollastonite.
2. The white, high-light-blocking polypropylene material according to claim 1, characterized in that: The dispersant is maleic anhydride-grafted polypropylene wax or polypropylene wax.
3. The white, high-light-blocking polypropylene material according to claim 1, characterized in that: The antioxidant is selected from at least one of antioxidant 1010, antioxidant 168 and antioxidant 1076.
4. A method for preparing the white high-opacity polypropylene material according to claim 1, characterized in that... Includes the following steps: S1. Add polypropylene resin, modified calcite, modified wollastonite, dispersant and antioxidant to a mixer and mix at high speed. S2. The mixture is added to a twin-screw extruder for extrusion granulation to obtain the white high-opacity polypropylene material.