Migration-resistant and anti-UV aging PPR material and preparation method thereof

Abstract

Belonging to the field of high polymer material preparation, the invention discloses a migration-resistant anti-UV aging PPR material, which is prepared from the following raw materials by weight: PPR resin, a composite ultraviolet absorbent, a composite free radical scavenger, a carrier, a light screener, a modified rare earth oxide, a nucleating agent and a dispersant. The composite ultraviolet absorbent is obtained by mixing 2-hydroxy-4-acrylate benzophenone and 2 '-(2'-hydroxy-3 '-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole, and the composite free radical capturing agent is obtained by mixing 2, 2, 6, 6-tetramethyl-4-methacrylate piperidinol and 4-benzoyloxy-2, 2, 6, 6-tetramethylpiperidine. On the whole, after the components and the process are optimized, the PPR material with remarkable migration-resistant and anti-UV aging effects can be prepared, and the PPR material is excellent in thermal stability and mechanical property.

Description

Technical Field

[0001] The invention relates to the field of polymer material preparation, and in particular to a migration-resistant and UV-resistant PPR material and a preparation method thereof. Background Art

[0002] PPR is the abbreviation of random copolymer polypropylene (polypropylene random), which is favored due to its good toughness, high strength, excellent processing performance, and good creep resistance at high temperatures. PPR pipes are also widely used in building water supply and drainage, urban and rural water supply and drainage, city gas, electricity and optical cable sheathing, industrial fluid transportation, agricultural irrigation and other construction, municipal, industrial and agricultural fields.

[0003] Existing studies have shown that ultraviolet light in the solar spectrum has a strong destructive effect on PPR materials. The wavelength range of sunlight reaching the ground is about 190~3000nm, of which the photon energy of 700~300nm wavelength is about 170~390kJ / moL, while the energy required for CC single bond rupture is only 340 kJ / moL. The UV-B region (295~315nm) and UV-A region (315~400nm) in the solar ultraviolet range can cause photodegradation and loss of PPR materials, and the light energy of 400~760nm in the visible light region mainly causes thermal oxidation aging of PPR materials. The PPR material chain segments absorb ultraviolet light and break, and the activation energy required is much lower than the activation energy required for rupture due to absorption of heat. Among the sunlight that reaches the ground, although the ultraviolet light with a wavelength of 290~400nm can mainly cause the photodegradation of PPR materials, the ozone layer has become hollow and thinner due to the intensification of air pollution in recent years. The ultraviolet light with a wavelength of 190~290nm, which was originally difficult to penetrate the air, can now reach the ground, and the energy of ultraviolet light has increased, which makes the aging effect of sunlight more intense. At the same time, due to the presence of a large number of tertiary carbon structures in the molecular chain structure of the PPR material itself, free radicals are formed after absorbing ultraviolet light, causing the polymer chain segments to break and produce chromophores, which continue to absorb ultraviolet light, causing the photodegradation process to continue and accelerate. In the photodegradation process of PPR materials, oxygen in the air can react quickly with free radicals to form a large number of highly active peroxide free radicals, which promote the free radicals to undergo faster photooxidative dehydrogenation reactions, thereby causing the molecular chain of PPR materials to break, degrade, and cross-link. Light aging reaction can also cause PPR materials to fade and turn yellow, affecting their appearance, and causing their molecular weight to decrease or cross-link, making the PPR materials hard, brittle, and cracked, and their mechanical properties gradually deteriorate, eventually losing their use value. Therefore, in the prior art, research on the migration resistance and UV aging resistance of PPR materials has also put forward increasingly higher requirements.

[0004] For example, the Chinese patent application number CN201310500794.3 discloses a PPR pipe with high aging resistance and a method for manufacturing the same. This method can form a ZnO layer inside and on the surface of the pipe by adding zinc powder, which significantly improves the anti-aging performance of the pipe. However, the composition is single and cannot cope with more wavelengths of ultraviolet light, so the anti-aging effect is limited. Another example is the Chinese patent application number CN201811057201.X, which discloses an aging-resistant PPR pipe and a method for preparing the same. By adding lignin to the PPR raw material, the unique hindered phenol structure can effectively capture the free radicals generated in photo-oxidative aging and thermal-oxidative aging, thereby improving the light stability and thermal stability of the PPR pipe, but the migration resistance is not ideal. Therefore, the prior art still needs to develop more solutions to improve the migration resistance and UV aging resistance of PPR materials to meet market demand, which is of great significance. Summary of the invention

[0005] Based on this, in order to solve the technical problem that the PPR material in the prior art has poor anti-UV aging performance, the present invention provides a migration-resistant and UV-resistant PPR material and a preparation method thereof. The specific technical scheme is as follows: A migration-resistant and UV-resistant PPR material, the PPR material comprising the following raw materials in parts by weight: 100 parts of PPR resin, 0.01 to 0.05 parts of a composite ultraviolet absorber, 0.01 to 0.7 parts of a composite free radical scavenger, 1 to 5 parts of a carrier, 1 to 5 parts of a light shielding agent, 0.01 to 0.08 parts of a modified rare earth oxide, 0.5 to 0.9 parts of a nucleating agent, and 0.01 to 0.03 parts of a dispersant; The composite ultraviolet absorber is obtained by mixing 2-hydroxy-4-acrylate benzophenone and 2'-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole in a mass ratio of (1-5): (1-2); The composite free radical scavenger is obtained by mixing 2,2,6,6-tetramethyl-4-methylacrylate piperidinol and 4-benzoyloxy-2,2,6,6-tetramethylpiperidine in a mass ratio of (1-9):(1-5).

[0006] Furthermore, the melt index of the PPR resin at 230° C. and 2.16 kg is (0.25-0.35) g / 10 min.

[0007] Furthermore, the light shielding agent is carbon black, and the oil absorption value of the carbon black is (130-190) mL / 100 g. Furthermore, the modified rare earth oxide is obtained by subjecting rare earth oxide to modification treatment, and the rare earth oxide is at least one of lanthanum oxide and cerium oxide. Furthermore, the modification treatment is: adding rare earth oxide to a silane coupling agent, and subjecting the mixture to ball milling treatment for 5 min to 20 min at a temperature of 55° C. to 75° C.

[0008] Furthermore, the nucleating agent is at least one of bis(4-tert-butyl) sodium phosphate and 2,2-methylene-bis(4,6-di-tert-butylphenyl) sodium phosphate.

[0009] Furthermore, the carrier is a copolymer of octadecyl vinyl ether and maleic anhydride.

[0010] In addition, the present invention also provides a method for preparing a PPR material, the preparation method comprising the following steps: The composite ultraviolet absorber, the composite free radical scavenger, the carrier and the dispersant are mixed, and stirred at 70°C to 90°C for 10min to 20min to obtain a mixture A; Adding PPR resin, light shielding agent, modified rare earth oxide and nucleating agent into the mixture A, mixing at a speed of 500 r / min to 800 r / min for 5 min to 10 min to obtain a mixture B; The mixture B is added into a twin-screw extruder, and then melted, extruded, cooled, pulled, and cut to obtain a PPR material.

[0011] Furthermore, the melting temperature is 220°C to 235°C, and the melting time is 10min to 20min.

[0012] Furthermore, the cooling process adopts water cooling, and the cooling rate is 5°C / min~10°C / min.

[0013] Compared with the prior art, this application has the following beneficial effects: 1. In this application, by compounding 2-hydroxy-4-acrylate benzophenone with active double bonds and 2'-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole, ultraviolet light can be efficiently absorbed and converted into heat energy for dissipation, reducing the energy directly received by the PPR material from ultraviolet radiation, and at the same time, the migration resistance effect of the composite ultraviolet absorber in the PPR matrix is ​​significantly improved. In addition, the compounding of 2,2,6,6-tetramethyl-4-methylacrylate piperidinol with active double bonds and 4-benzoyloxy-2,2,6,6-tetramethylpiperidine can effectively act on the free radicals formed in the PPR matrix and make them more stable. At the same time, the compound ultraviolet absorber and the compound free radical scavenger can cope with more ultraviolet rays of different wavelengths, achieve a synergistic effect, and significantly reduce the photodegradation of PPR materials.

[0014] 2. This application achieves a certain protective effect by adding a light shielding agent to reduce the ultraviolet light exposure of the PPR material through physical means, and combines a composite ultraviolet absorber and a composite free radical scavenger to make improvements from chemical and physical aspects, which helps to improve the migration resistance and UV aging resistance of the PPR material.

[0015] 3. By adding modified rare earth oxides, the present application not only has high compatibility in PPR materials, but also can improve the thermal stability of PPR materials and improve their mechanical properties.

[0016] 4. The present invention uses a copolymer of octadecyl vinyl ether and maleic anhydride as a carrier, interacts with a composite ultraviolet absorber and a composite free radical scavenger, and then adds it to the PPR matrix after cross-linking. It has higher stability and can reduce migration under heat and light, exerting a better anti-UV aging effect, thereby increasing the service life of the PPR material. DETAILED DESCRIPTION

[0017] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific implementation methods described herein are only used to explain the present invention and do not limit the protection scope of the present invention.

[0018] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0019] A migration-resistant and UV-resistant PPR material in one embodiment of the present invention comprises the following raw materials in parts by weight: 100 parts of PPR resin, 0.01 to 0.05 parts of a composite ultraviolet absorber, 0.01 to 0.7 parts of a composite free radical scavenger, 1 to 5 parts of a carrier, 1 to 5 parts of a light shielding agent, 0.01 to 0.08 parts of a modified rare earth oxide, 0.5 to 0.9 parts of a nucleating agent, and 0.01 to 0.03 parts of a dispersant; The composite ultraviolet absorber is obtained by mixing 2-hydroxy-4-acrylate benzophenone and 2'-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole in a mass ratio of (1-5): (1-2); The composite free radical scavenger is obtained by mixing 2,2,6,6-tetramethyl-4-methylacrylate piperidinol and 4-benzoyloxy-2,2,6,6-tetramethylpiperidine in a mass ratio of (1-9):(1-5).

[0020] In one embodiment, the melt index of the PPR resin at 230° C. and 2.15 kg is (0.25-0.35) g / 10 min.

[0021] In one embodiment, the light shielding agent is carbon black, and the oil absorption value of the carbon black is (130-190) mL / 100 g. In one embodiment, the modified rare earth oxide is obtained by modifying the rare earth oxide, and the rare earth oxide is at least one of lanthanum oxide and cerium oxide. In one embodiment, the modification treatment is: adding rare earth oxide to a silane coupling agent, and ball milling for 5 min to 20 min at 55° C. to 75° C.

[0022] In one embodiment, the nucleating agent is at least one of sodium bis(4-tert-butyl) phosphate and sodium 2,2-methylene-bis(4,6-di-tert-butylphenyl) phosphate.

[0023] In one embodiment, the carrier is a copolymer of octadecyl vinyl ether and maleic anhydride.

[0024] In one embodiment, the dispersant is at least one of polyethylene wax and ethylene bisstearamide.

[0025] In addition, the present invention also provides a method for preparing a PPR material, the preparation method comprising the following steps: The composite ultraviolet absorber, the composite free radical scavenger, the carrier and the dispersant are mixed, and stirred at 70°C to 90°C for 10min to 20min to obtain a mixture A; Adding PPR resin, light shielding agent, modified rare earth oxide and nucleating agent into the mixture A, mixing at a speed of 500 r / min to 800 r / min for 5 min to 10 min to obtain a mixture B; The mixture B is added into a twin-screw extruder, and then melted, extruded, cooled, pulled, and cut to obtain a PPR material.

[0026] In one embodiment, the melting temperature is 220°C to 235°C, and the melting time is 10 min to 20 min.

[0027] In one embodiment, the cooling process adopts water cooling, and the cooling rate is 5°C / min~10°C / min.

[0028] In the above scheme, through the optimization of components and processes, a PPR material that is resistant to migration and UV aging can be obtained as a whole.

[0029] The embodiments of the present invention will be described in detail below with reference to specific examples.

[0030] It should be noted that the amounts of raw materials added in the following examples are in parts by weight.

[0031] Embodiment 1: A method for preparing a PPR material, the method comprising the following steps: A composite ultraviolet absorber is obtained by mixing 2-hydroxy-4-acrylate benzophenone and 2'-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole in a mass ratio of 3:2; A composite free radical scavenger is obtained by mixing 2,2,6,6-tetramethyl-4-methylacrylate piperidinol and 4-benzoyloxy-2,2,6,6-tetramethylpiperidine in a mass ratio of 5:2; Lanthanum oxide was added to a silane coupling agent, and ball-milled for 15 min at 65° C. to obtain a modified rare earth oxide. 0.05 parts of the composite ultraviolet absorber, 0.5 parts of the composite free radical scavenger, 3 parts of a copolymer of octadecyl vinyl ether and maleic anhydride, and 0.02 parts of polyethylene wax were mixed, and stirred at 85° C. for 15 minutes to obtain a mixture A; 100 parts of PPR resin, 3 parts of carbon black, 0.03 parts of the modified rare earth oxide, and 0.6 parts of sodium di(4-tert-butyl) phosphate were added to the mixture A, and the mixture was mixed at a speed of 500 r / min for 7 minutes to obtain a mixture B; The mixture B was added into a twin-screw extruder, melted at 225° C. for 15 minutes, extruded, water-cooled at a cooling rate of 5° C. / min, and pulled and cut to obtain a PPR material.

[0032] Embodiment 2: A method for preparing a PPR material, the method comprising the following steps: A composite ultraviolet absorber is obtained by mixing 2-hydroxy-4-acrylate benzophenone and 2'-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole in a mass ratio of 4:1; A composite free radical scavenger is obtained by mixing 2,2,6,6-tetramethyl-4-methylacrylate piperidinol and 4-benzoyloxy-2,2,6,6-tetramethylpiperidine in a mass ratio of 4:3; Lanthanum oxide was added to a silane coupling agent, and ball-milled for 12 minutes at 70°C to obtain a modified rare earth oxide. 0.04 parts of the composite ultraviolet absorber, 0.6 parts of the composite free radical scavenger, 4 parts of a copolymer of octadecyl vinyl ether and maleic anhydride, and 0.03 parts of polyethylene wax were mixed, and stirred at 88° C. for 15 minutes to obtain a mixture A; 100 parts of PPR resin, 4 parts of carbon black, 0.04 parts of the modified rare earth oxide, and 0.7 parts of sodium di(4-tert-butyl) phosphate were added to the mixture A, and the mixture was mixed at a speed of 500 r / min for 10 minutes to obtain a mixture B; The mixture B was added into a twin-screw extruder, melted at 225° C. for 15 minutes, extruded, water-cooled at a cooling rate of 5° C. / min, and towed and cut to obtain a PPR material.

[0033] Embodiment 3: A method for preparing a PPR material, the method comprising the following steps: A composite ultraviolet absorber is obtained by mixing 2-hydroxy-4-acrylate benzophenone and 2'-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole in a mass ratio of 3:2; A composite free radical scavenger is obtained by mixing 2,2,6,6-tetramethyl-4-methylacrylate piperidinol and 4-benzoyloxy-2,2,6,6-tetramethylpiperidine in a mass ratio of 2:5; Lanthanum oxide was added to a silane coupling agent, and ball-milled for 10 min at 75° C. to obtain a modified rare earth oxide. 0.03 parts of the composite ultraviolet absorber, 0.7 parts of the composite free radical scavenger, 5 parts of a copolymer of octadecyl vinyl ether and maleic anhydride, and 0.03 parts of polyethylene wax were mixed, and stirred at 90° C. for 20 minutes to obtain a mixture A; 100 parts of PPR resin, 3 parts of carbon black, 0.05 parts of the modified rare earth oxide, and 0.6 parts of sodium di(4-tert-butyl) phosphate were added to the mixture A, and the mixture was mixed at a speed of 500 r / min for 10 minutes to obtain a mixture B; The mixture B was added into a twin-screw extruder, melted at 230° C. for 10 min, extruded, water-cooled at a cooling rate of 8° C. / min, and pulled and cut to obtain a PPR material.

[0034] Comparative Example 1: Compared with Example 3, Comparative Example 1 adds a single 2-hydroxy-4-acrylate benzophenone as a UV absorber, and the rest is the same as Example 3.

[0035] Comparative Example 2: Comparative Example 2 Compared with Example 3, in Comparative Example 2, a single 2'-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole is added as a UV absorber, and the rest is the same as Example 3.

[0036] Comparative Example 3: Compared with Example 3, Comparative Example 3 adds a single 2,2,6,6-tetramethyl-4-methylacrylate piperidinol as a free radical scavenger, and the rest is the same as Example 3.

[0037] Comparative Example 4: Compared with Example 3, Comparative Example 4 uses a single 4-benzoyloxy-2,2,6,6-tetramethylpiperidine as a free radical scavenger, and the rest is the same as Example 3.

[0038] Comparative Example 5: Comparative Example 5 Compared with Example 3, the composite ultraviolet absorber and the composite free radical scavenger in Comparative Example 5 are not pre-mixed with the copolymer of octadecyl vinyl ether and maleic anhydride, and the rest is the same as Example 3, that is, the preparation process in Comparative Example 5 is as follows: 0.03 parts of the composite ultraviolet absorber, 0.7 parts of the composite free radical scavenger, 0.03 parts of polyethylene wax, 100 parts of PPR resin, 3 parts of carbon black, 0.05 parts of the modified rare earth oxide, and 0.6 parts of di(4-tert-butyl) sodium phosphate were mixed uniformly, and the mixture was mixed at a speed of 500 r / min for 10 minutes to obtain a mixture; The mixture was added into a twin-screw extruder, melted at 230° C. for 10 minutes, extruded, water-cooled at a cooling rate of 8° C. / min, and pulled and cut to obtain a PPR material.

[0039] Comparative Example 6: The difference between Comparative Example 6 and Example 3 is that no composite ultraviolet absorber is added in Comparative Example 6, and the rest is the same as Example 3.

[0040] Comparative Example 7: The difference between Comparative Example 7 and Example 3 is that no composite free radical scavenger is added in Comparative Example 7, and the rest is the same as Example 3.

[0041] Comparative Example 8: The difference between Comparative Example 8 and Example 3 is that no modified rare earth oxide is added in Comparative Example 8, and the rest is the same as Example 3.

[0042] Comparative Example 9: Compared with Example 3, Comparative Example 9 does not add carbon black (light shielding agent), and the rest is the same as Example 3.

[0043] The PPR material samples prepared in Examples 1 to 3 and the PPR material comparison samples prepared in Comparative Examples 1 to 9 were subjected to performance tests, and the apparent conditions at 85°C and 80% humidity for 1000 hours were recorded; the tensile strength retention rate (%) and the flexural modulus retention rate (%) of the 2000-hour UV aging test (method according to GB / T16422-2014) were shown in Table 1 below.

[0044] Table 1: Performance results

[0045] From the data analysis of Table 1, it can be seen that after the raw materials are optimized, the synergistic effect between the components of the present invention can achieve a significant anti-ultraviolet effect. Specifically, the difference between Comparative Examples 1 to 2 and Example 3 is that the addition of ultraviolet absorbers is different, but the yellowing index and the anti-ultraviolet effect are obviously worse than those of Example 3, indicating that the addition of a composite ultraviolet absorber in the present application can achieve the purpose of synergistic enhancement; the difference between Comparative Examples 3 to 4 and Example 3 is that the components of the free radical scavenger are different, but it can be seen that the yellowing index is higher and the anti-ultraviolet effect is poor, indicating that the synergistic effect between the components of the composite free radical scavenger can also improve the anti-ultraviolet effect; the difference between Comparative Example 5 and Example 3 is that no carrier is added in Comparative Example 5, but a slight stickiness occurs, and the yellowing The index is high and the anti-ultraviolet effect is poor, indicating that the carrier can promote the cross-linking of the composite ultraviolet agent and the composite free radical scavenger to form a more stable use state; Comparative Example 6 does not add a composite ultraviolet absorber, and Comparative Example 7 does not add a composite free radical scavenger. It can also be seen that its yellowing index is significantly higher than that of Example 3, and the anti-ultraviolet effect is significantly poor, indicating that there is also an interaction between the composite ultraviolet absorber and the composite free radical scavenger, a synergistic effect, and the compounding of the components achieves an effect of 1+1>2; Comparative Example 8 does not add modified rare earth oxides, and Comparative Example 9 does not add carbon black. Although the anti-ultraviolet effect is better than that of Comparative Examples 1 to 7, it is worse than that of Example 3, indicating that the addition of modified rare earth oxides and carbon black has a certain effect on the anti-ultraviolet effect. Therefore, as a complete formulation system, this application has an excellent migration resistance effect after optimizing the ingredients and the ratio of the ingredients, so that the effective ingredients can exert their anti-ultraviolet performance for a long time, and can obtain PPR materials with excellent apparent quality and significant anti-ultraviolet effect.

[0046] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0047] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A PPR material resistant to migration and UV aging, characterized in that: The PPR material comprises the following raw materials in parts by weight: 100 parts of PPR resin, 0.01 to 0.05 parts of composite ultraviolet absorber, 0.01 to 0.7 parts of composite free radical scavenger, 1 to 5 parts of carrier, 1 to 5 parts of light shielding agent, 0.01 to 0.08 parts of modified rare earth oxide, 0.5 to 0.9 parts of nucleating agent and 0.01 to 0.03 parts of dispersant; The composite ultraviolet absorber is obtained by mixing 2-hydroxy-4-acrylate benzophenone and 2'-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole in a mass ratio of (1-5): (1-2); The composite free radical scavenger is obtained by mixing 2,2,6,6-tetramethyl-4-methylacrylate piperidinol and 4-benzoyloxy-2,2,6,6-tetramethylpiperidine in a mass ratio of (1-9):(1-5).

2. The PPR material according to claim 1, characterized in that: The melt index of the PPR resin at 230° C. and 2.16 kg is (0.25-0.35) g / 10 min.

3. The PPR material according to claim 1, characterized in that: The light shielding agent is carbon black, and the oil absorption value of the carbon black is (130-190) mL / 100 g.

4. The PPR material according to claim 1, characterized in that: The modified rare earth oxide is obtained by subjecting rare earth oxide to modification treatment, and the rare earth oxide is at least one of lanthanum oxide and cerium oxide.

5. The PPR material according to claim 4, characterized in that: The modification treatment is as follows: adding rare earth oxide to a silane coupling agent, and subjecting the mixture to ball milling for 5 to 20 minutes at a temperature of 55 to 75°C.

6. The PPR material according to claim 1, characterized in that: The nucleating agent is at least one of bis(4-tert-butyl) sodium phosphate and 2,2-methylene-bis(4,6-di-tert-butylphenyl) sodium phosphate.

7. The PPR material according to claim 1, characterized in that: The carrier is a copolymer of octadecyl vinyl ether and maleic anhydride.

8. A method for preparing a PPR material, characterized in that: The preparation method is used to prepare the PPR material according to any one of claims 1 to 7, and the preparation method comprises the following steps: The composite ultraviolet absorber, the composite free radical scavenger, the carrier and the dispersant are mixed, and stirred at 70°C to 90°C for 10min to 20min to obtain a mixture A; Adding PPR resin, light shielding agent, modified rare earth oxide and nucleating agent into the mixture A, mixing at a speed of 500 r / min to 800 r / min for 5 min to 10 min to obtain a mixture B; The mixture B is added into a twin-screw extruder, and then melted, extruded, cooled, pulled, and cut to obtain a PPR material.

9. The preparation method according to claim 8, characterized in that: The melting temperature is 220° C. to 235° C., and the melting time is 10 min to 20 min.

10. The preparation method according to claim 8, characterized in that: The cooling process adopts water cooling, and the cooling rate is 5°C / min~10°C / min.

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