CN-122011545-A - Polyethylene composition and preparation method and application thereof

Abstract

The invention relates to a polyethylene composition, a preparation method and application thereof, and belongs to the technical field of compositions of high molecular compounds. The polyethylene composition comprises, by weight, 74-100 parts of polyethylene, 0.2-10 parts of a fluorinated elastomer, 1-10 parts of a light aging resistant agent, 0.5-5 parts of lamellar inorganic filler, 0.5-3 parts of a light shielding agent, 0.1-0.5 part of an antioxidant and 0.1-1 part of a weather resistant agent, wherein the light aging resistant agent is a silicon dioxide immobilized hindered amine, and the weather resistant agent comprises an ultraviolet light absorber and a free radical scavenger. The polyethylene composition can effectively improve the elongation at break attenuation after photo-aging and maintain good environmental stress cracking resistance.

Inventors

• YIN CHAOQING
• LI CHENG
• ZHANG SHUANGSHUANG
• LI QILONG
• YANG LEI
• ZHOU JIE
• WU ZHAOMIAN
• WANG HAI

Assignees

• 上海金发科技发展有限公司
• 江苏金发科技新材料有限公司

Dates

Publication Date

20260512

Application Date

20260129

Claims (10)

1. 1. The polyethylene composition is characterized by comprising the following components in parts by weight: 74-100 parts of polyethylene, 0.2-10 parts of fluorinated elastomer, 1-10 parts of light aging resistant agent, 0.5-5 parts of lamellar inorganic filler, 0.5-3 parts of light shielding agent, 0.1-0.5 part of antioxidant and 0.1-1 part of weather resistant agent; The photo-aging resistant agent is a silica-immobilized hindered amine, and the silica-immobilized hindered amine comprises silica, a silane coupling agent and hindered amine; The weathering agent includes an ultraviolet light absorber and a free radical scavenger.
2. 2. The polyethylene composition according to claim 1, wherein the mass fraction of hindered amine in the photo-aging inhibitor relative to silica is from 10% to 30%.
3. 3. The polyethylene composition according to claim 1, wherein the mass fraction of the silane coupling agent in the photo-aging resistant agent is 5% to 20% relative to silica.
4. 4. The polyethylene composition of claim 1, wherein the mass ratio of ultraviolet light absorber to radical scavenger is from 1:0.8 to 1:1.2.
5. 5. The polyethylene composition of claim 1, further comprising a hydrogenated petroleum resin in a mass ratio of the hydrogenated petroleum resin to the lamellar inorganic filler of 1:2 to 1:10.
6. 6. The polyethylene composition of claim 1, wherein the polyethylene has a melt mass flow rate of 0.1g/10min to 10g/10min at 190 ℃ and 2.16 kg.
7. 7. The polyethylene composition according to claim 1, wherein the lamellar inorganic filler comprises at least one of montmorillonite, magnesium hydroxide, hydrotalcite, and/or the light shielding agent comprises at least one of carbon black, titanium white, zinc oxide, cerium oxide.
8. 8. A process for producing a polyethylene composition according to any one of claims 1 to 7, comprising the step of uniformly mixing the components and melt-extruding the mixture to obtain a polyethylene composition.
9. 9. Use of the polyethylene composition according to any of claims 1 to 7 for the preparation of cable jackets, electronic packages, pipes, packaging materials.
10. 10. An article made from the polyethylene composition of any one of claims 1 to 7.

Description

Polyethylene composition and preparation method and application thereof Technical Field The invention relates to the technical field of compositions of high molecular compounds, in particular to a polyethylene composition, a preparation method and application thereof. Background Polyethylene has excellent chemical stability, high toughness, good electrical insulation and processability, and is widely applied to the fields of cable sheaths, electronic element encapsulation, pipelines, packaging materials and the like. However, polyethylene is susceptible to photo-aging under outdoor conditions due to prolonged light exposure, which results in a substantial reduction in elongation at break. Although the photo aging resistance of polyethylene can be improved by adding the UV-resistant agent, the UV-resistant agent is easy to migrate and be consumed in a hot and humid environment (such as spraying), and the service life of the polyethylene material is difficult to effectively improve. At the same time, photo-aging also affects crosslinking, post-crystallization and molecular chain degradation of the polyethylene, thereby increasing the risk of stress cracking of the polyethylene material. Disclosure of Invention The invention aims to overcome the defects of the prior art and provide a polyethylene composition, a preparation method and application thereof. In order to achieve the above purpose, the technical scheme adopted by the invention is as follows: The invention provides a polyethylene composition, which comprises, by weight, 74-100 parts of polyethylene, 0.2-10 parts of fluorinated elastomer, 1-10 parts of photo-aging resistant agent, 0.5-5 parts of lamellar inorganic filler, 0.5-3 parts of light shielding agent, 0.1-0.5 part of antioxidant and 0.1-1 part of weather resistant agent; The photo-aging resistant agent is a silica-immobilized hindered amine, and the silica-immobilized hindered amine comprises silica, a silane coupling agent and hindered amine; The weathering agent includes an ultraviolet light absorber and a free radical scavenger. According to the invention, polyethylene is taken as matrix resin, the crystallinity of the polyethylene is reduced by introducing fluorinated elastomer, so that local stress absorption and dispersion are promoted to inhibit stress concentration at the interfaces of a crystal area and an amorphous area, further generation and expansion of microcracks in the aging process are reduced, fluorine in the fluorinated elastomer is utilized to improve hydrophobicity and oleophobicity to reduce degradation of polyethylene composition performance by a spraying environment, meanwhile, the polyethylene is combined with silica immobilized hindered amine, on one hand, the polyethylene can be cooperated with the fluorinated elastomer to inhibit extraction of an antioxidant and a weather resistant agent by the spraying environment, on the other hand, the hindered amine is bonded or adsorbed and fixed on the surface of silica particles, migration or volatilization of the hindered amine can be reduced, even distribution of active sites of the hindered amine in the polyethylene matrix can be promoted, further high free radical capture efficiency under long-term aging condition is realized, and the weather resistant agent and light shielding agent containing ultraviolet light absorber and free radical capture agent can form a multi-level cooperative shielding-absorbing-capturing system, on the other hand, the lamellar inorganic filler and the antioxidant can effectively inhibit extraction of the antioxidant and the oxidation environment, and the mutual effective stress reduction of the polyethylene can be effectively inhibited after the mutual stress reduction and the aging resistance of the polyethylene is well-aged and the aging resistance is kept. The polyethylene in the polyethylene composition is taken as matrix resin, the mass ratio of the polyethylene is more than or equal to 45 percent based on the total mass of the polyethylene composition, and the fluorinated elastomer is a copolymer (PFE) elastomer taking Tetrafluoroethylene (TFE) and perfluorovinyl ether (PFVE) as main monomers. In some embodiments, the particle size D50 of the silica in the silica-immobilized hindered amine is from 1 μm to 10 μm, for example, may be, but not limited to, a range of values of any one or any two of 1 μm, 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, 10 μm. The particle diameter D50 of the silicon dioxide can be measured by referring to GB/T19077.1-2008 particle size analysis laser diffraction method. In some embodiments, the parts by weight of polyethylene in the polyethylene composition may specifically be, but is not limited to, any one or any two of the range values of 74 parts, 75 parts, 76 parts, 78 parts, 80 parts, 82 parts, 84 parts, 86 parts, 88 parts, 90 parts, 92 parts, 94 parts, 96 parts, 98 parts, 100 parts. In some embodiments, the parts by weight of the fluorinated elastomer i