Recycled polypropylene reinforcing and toughening master batch and preparation method thereof

Abstract

The invention provides a recycled polypropylene reinforced and toughened master batch and a preparation method of the recycled polypropylene reinforced and toughened master batch. The recycled polypropylene reinforced and toughened master batch is prepared from the following components: 10 to 45 parts of high-fluidity recycled polypropylene resin, 5 to 10 parts of recycled polyethylene resin, 5 to 10 parts of recycled thermoplastic polyolefin elastomer, 30 to 50 parts of talcum powder, 10 to 20 parts of recycled silicon dioxide powder, 0.1 to 10 parts of compatilizer, 0.1 to 5 parts of dispersing agent and 0.1 to 5 parts of antioxidant. The master batch is applied to reinforcement and toughening of recycled polypropylene, toughness of the recycled polypropylene can be improved, rigidity of the recycled polypropylene can be greatly improved, and due to the fact that most of the components of the master batch are recycled materials, performance can be guaranteed, and meanwhile production cost can be reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of polymer materials, and particularly to a recycled polypropylene reinforcing and toughening masterbatch and a preparation method thereof. Background Art

[0002] As a mature general polymer material, polypropylene (PP) is widely used in fields such as automobiles, household appliances, food packaging, building materials, etc. due to its advantages of low density, easy processing and molding, good corrosion resistance of products, non-toxic and harmless, and low cost. However, due to its poor impact resistance, the application of this material in these fields is limited to a certain extent. In order to expand the application range of polypropylene, scholars at home and abroad have carried out a large number of studies on the modification of polypropylene. Whether a polymer material can be used as an engineering material mainly depends on its two important properties, rigidity and toughness. Compared with the limitations of high equipment requirements and cumbersome processes for chemical copolymerization, physical blending is widely used because of its advantages of simplicity, obvious effect and low cost. Physical blending is usually a processing method of mixing two or more homopolymers or copolymers in a certain proportion to obtain a polymer blend. The binding mode between the components in the obtained blend is mainly physical binding.

[0003] Most additives in conventional physical blending are powdery materials. Direct mixing will cause dust to fly, which is harmful to the health of operators, and it is difficult to disperse the additives evenly in the resin. Plastic modification masterbatch is a new type of modified material, mainly composed of carrier resin, modifier and processing aids, which contains a high concentration of modifier and is evenly dispersed in the carrier resin with the help of processing aids. In the actual production process, only a small amount of modification masterbatch needs to be added to the raw materials to meet the corresponding mechanical property requirements. Developing a masterbatch that can increase the impact strength of polypropylene and at the same time increase its rigidity is a technical problem that needs to be solved by those skilled in the art. Summary of the Invention

[0004] In view of the above situation, the present invention provides a recycled polypropylene reinforcing and toughening masterbatch and a preparation method thereof, which can effectively improve the impact strength of recycled polypropylene, increase its rigidity at the same time, and compared with directly using additives, not only simplifies the additive mixing process, but also improves the dust flying.

[0005] One aspect of the present invention provides a recycled polypropylene reinforcing and toughening masterbatch, which comprises the following components in parts by weight: 10 - 45 parts of high-flow recycled polypropylene resin, 5 - 10 parts of recycled polyethylene resin, 5 - 10 parts of recycled thermoplastic polyolefin elastomer, 30 - 50 parts of talcum powder, 10 - 20 parts of recycled silica powder, 0.1 - 10 parts of compatibilizer, 0.1 - 5 parts of dispersant, and 0.1 - 5 parts of antioxidant.

[0006] Preferably, the high-flow recycled polypropylene resin is prepared by crushing, cleaning, and drying the polypropylene plastic from scrapped washing machines. Its main components are homopolypropylene, calcium carbonate inorganic filler, and color powder. The melt index is 40 - 60 g / min, and the Izod notched impact strength is 3 - 6 KJ / m 2 。

[0007] Preferably, the recycled polyethylene resin is prepared by recycling and crushing plastic pipes. Its main components are high-density polyethylene, calcium carbonate, color powder pigment, and processing aids. The melt index is 3 - 8 g / min, and the Izod notched impact strength is 40 - 60 KJ / m 2 。

[0008] Preferably, the recycled thermoplastic polyolefin elastomer is prepared by crushing and processing toy recycling materials, and is a combination of one or more of TPE, TPR, TPV, TPU, and TPO.

[0009] Preferably, the talc powder has a flaky structure and a mesh number of 1000 - 3000 mesh.

[0010] Preferably, the recycled silica powder has a spherical structure and a mesh number of 500 - 1500 mesh.

[0011] Preferably, the compatibilizer is a combination of one or more of PE-g-ST, PP-g-ST, ABS-g-MAH, PE-g-MAH, and PP-g-MAH.

[0012] Preferably, the dispersant is a combination of one or more of polyethylene wax, EBS, erucamide, paraffin wax, and stearic acid.

[0013] Preferably, the antioxidant is a mixture of phenolic antioxidants and phosphate antioxidants.

[0014] Another aspect of the present invention provides a method for preparing the above-mentioned recycled polypropylene reinforcing and toughening masterbatch, including the following steps:

[0015] (1) Weigh talc powder and recycled silica powder, dry them in an oven at 100 °C for 4 h, then take them out and put them into a sealed bag for later use to reduce the moisture content in the filler;

[0016] (2) Place the high-flow recycled polypropylene, recycled polyethylene resin, recycled thermoplastic polyolefin elastomer, talc powder, recycled silica powder, compatibilizer, dispersant, and antioxidant in a high-speed mixer, mix for 5 - 8 min until evenly mixed, then take them out and put them into the hopper of a screw extruder, and set a certain feeding rate to feed from the hopper;

[0017] (3) Set the extrusion temperature of the screw extruder to 180 - 220 °C, and the extrusion speed of the screw extruder to 200 - 500 rpm;

[0018] (4) After cooling and pelletizing the mixture extruded by the screw extruder, dry it to obtain the recycled polypropylene reinforced and toughened masterbatch.

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0020] 1. The present invention simplifies the auxiliary agent mixing process: the masterbatch has a particle size very close to that of the resin, and only simple mixing is required during batching.

[0021] 2. The present invention improves the dispersibility of the auxiliary agent: the carrier layer selected for the masterbatch is high-flow recycled polypropylene with a melt index > 50 g / min, which is beneficial to the uniform dispersion of the auxiliary agent in the resin and enables the auxiliary agent to fully exert its performance.

[0022] 3. The present invention utilizes recycled polyethylene resin, recycled thermoplastic polyolefin elastomer, talc powder, recycled silica powder, and compatibilizer to form core-shell structured particles with talc powder and recycled silica powder as the hard core and recycled polyethylene resin and recycled thermoplastic polyolefin elastomer as the soft shell. This structure effectively combines the rigidity and toughness of the auxiliary agent.

[0023] 4. The main function of the filling masterbatch is to reduce the cost of the product and appropriately improve certain properties of the product, such as rigidity and toughness. Using the filling masterbatch can increase the addition amount of the filler in the resin, and the performance is improved compared with directly adding the filler. Specific Embodiments

[0024] To facilitate the understanding of the present invention, the present invention will be described more comprehensively with reference to each embodiment below. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thorough and comprehensive.

[0025] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present invention belongs. The terms used in the specification of the present invention herein 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 of the related listed items.

[0026] An embodiment of the present invention provides a recycled polypropylene reinforcing and toughening masterbatch, which comprises the following components by weight: 10-45 parts of high-flow recycled polypropylene resin, 5-10 parts of recycled polyethylene resin, 5-10 parts of recycled thermoplastic polyolefin elastomer, 30-50 parts of talcum powder, 10-20 parts of recycled silica powder, 0.1-10 parts of compatibilizer, 0.1-5 parts of dispersant, and 0.1-5 parts of antioxidant.

[0027] In an alternative embodiment of the present invention, the high-flow recycled polypropylene resin is prepared by crushing, cleaning, and drying the polypropylene plastic from scrapped washing machines. Its main components are homopolypropylene, calcium carbonate inorganic filler, and color powder, with a melt index of 40-60 g / min and a cantilever beam notched impact strength of 3-6 KJ / m 2 。

[0028] In an alternative embodiment of the present invention, the recycled polyethylene resin is prepared by recycling and crushing plastic pipes. Its main components are high-density polyethylene, calcium carbonate, color powder pigment, and processing aids, with a melt index of 3-8 g / min and a cantilever beam notched impact strength of 40-60 KJ / m 2 。

[0029] In an alternative embodiment of the present invention, the recycled thermoplastic polyolefin elastomer is prepared by crushing and processing toy recycling materials and is a combination of one or more of thermoplastic elastomer (TPE), thermoplastic rubber (TPR), thermoplastic vulcanizate (TPV), thermoplastic polyurethane elastomer (TPU), and thermoplastic polyolefin (TPO).

[0030] In an alternative embodiment of the present invention, the talcum powder has a flaky structure and a mesh number of 1000-3000 mesh.

[0031] In an alternative embodiment of the present invention, the recycled silica powder has a spherical structure and a mesh number of 500-1500 mesh.

[0032] In an alternative embodiment of the present invention, the compatibilizer is a combination of one or more of PE-g-ST, PP-g-ST, ABS-g-MAH, PE-g-MAH, and PP-g-MAH.

[0033] In an alternative embodiment of the present invention, the dispersant is a combination of one or more of polyethylene wax, EBS, erucamide, paraffin wax, and stearic acid.

[0034] In an alternative embodiment of the present invention, the antioxidant is a mixture of phenolic antioxidants and phosphate antioxidants.

[0035] Another embodiment of the present invention provides the preparation method of the above-mentioned recycled polypropylene reinforcing and toughening masterbatch, including:

[0036] (1) Weigh talcum powder and recycled silica powder, dry them in an oven at 100 °C for 4 h, then take them out and put them into a sealed bag for standby to reduce the moisture content in the filler;

[0037] (2) Put high-flow recycled polypropylene, recycled polyethylene resin, recycled thermoplastic polyolefin elastomer, talcum powder, recycled silica powder, compatibilizer, dispersant, antioxidant into a high-speed mixer, mix for 5 - 8 min to make them evenly mixed, then take them out and put them into the feeding hopper of a screw extruder, and set a certain feeding rate to feed from the feeding hopper;

[0038] (3) Set the extrusion temperature of the screw extruder to 180 - 220 °C, and the extrusion speed of the screw extruder to 200 - 500 rpm;

[0039] (4) After cooling and pelletizing the mixture extruded by the screw extruder, dry it to obtain the recycled polypropylene reinforcing and toughening masterbatch.

[0040] The following further illustrates the embodiments of the present invention through multiple examples. The embodiments of the present invention are not limited to the following specific examples. Within the scope of the main rights unchanged, appropriate changes can be made for implementation.

[0041] A preparation method of a recycled polypropylene reinforcing and toughening masterbatch, including:

[0042] (1) Weigh talcum powder and recycled silica powder according to Table 1, dry them in an oven at 100 °C for 4 h, then take them out and put them into a sealed bag for standby to reduce the moisture content in the filler;

[0043] (2) Put raw materials such as high-flow recycled polypropylene, recycled polyethylene resin, recycled thermoplastic polyolefin elastomer, talcum powder, recycled silica powder, compatibilizer, polyethylene wax, antioxidant, etc. according to the mass ratio in Table 1 into a high-speed mixer, mix for 5 - 8 min to make them evenly mixed, then take them out and put them into the feeding hopper of a screw extruder, and set a certain feeding rate to feed from the feeding hopper;

[0044] (3) Set the extrusion temperature of the screw extruder to 180 - 220 °C; the extrusion speed of the screw extruder to 200 - 500 rpm.

[0045] (4) After cooling and pelletizing the mixture extruded by the screw extruder, dry it to obtain the masterbatch.

[0046] Table 1 Component composition of each example (parts by weight)

[0047]

[0048]

[0049] In Table 1 above, the highly fluid recycled polypropylene resin is prepared from the polypropylene plastic of scrapped washing machines through crushing, cleaning, and drying. Its main components are homopolypropylene, calcium carbonate inorganic filler, and color powder. The melt index is 50.1 g / min, and the Izod impact strength is 3.7 KJ / m 2 The recycled polyethylene resin is prepared by recycling and crushing plastic pipes. Its main components are high-density polyethylene, calcium carbonate, color powder pigment, and processing aids. The melt index is 5.7 g / min, and the Izod impact strength is 54.3 KJ / m 2 .

[0050] Comparative Example 1

[0051] By weight, 25 parts of highly fluid recycled polypropylene resin, 5 parts of recycled polyethylene resin, 10 parts of recycled thermoplastic polyolefin elastomer, 10 parts of talc powder, 50 parts of recycled silica powder, 2 parts of PP-g-MAH, 2 parts of polyethylene wax, and 0.5 part of antioxidant were weighed. Then, according to the method of Example 1, the filled masterbatch DM1 was prepared.

[0052] Comparative Example 2

[0053] By weight, 25 parts of highly fluid recycled polypropylene resin, 5 parts of recycled polyethylene resin, 10 parts of recycled thermoplastic polyolefin elastomer, 60 parts of talc powder, 2 parts of PP-g-MAH, 2 parts of polyethylene wax, and 0.5 part of antioxidant were weighed. Then, according to the method of Example 1, the filled masterbatch DM2 was prepared.

[0054] Comparative Example 3

[0055] By weight, 45 parts of highly fluid recycled polypropylene resin, 5 parts of recycled polyethylene resin, 10 parts of recycled thermoplastic polyolefin elastomer, 30 parts of talc powder, 10 parts of recycled silica powder, 2 parts of PP-g-MAH, 2 parts of polyethylene wax, and 0.5 part of antioxidant were weighed. During the preparation process, the difference between Comparative Example 3 and Example 1 was that instead of pre-preparing the core-shell structured particles, all the raw materials were directly put into the extruder and extruded and pelletized with recycled polypropylene.

[0056] The materials obtained in Examples 1 - 13 and Comparative Examples 1 - 3 were added to recycled polypropylene according to a mass ratio of 1:1 to prepare specimens and test their properties. The obtained results are as described in Table 2 below.

[0057] Table 2

[0058]

[0059] In Table 2, the recycled polypropylene raw material is recycled material from automobile interior decoration.

[0060] Comparative analysis of the embodiments and comparative examples

[0061] Combining Comparative Examples 1-2 and Example 1, it can be seen that talcum powder has a better reinforcing effect on the composite material when used as the reinforcing body of the filling masterbatch than when used as the reinforcing body of the filling masterbatch using recycled silica powder. This is because talcum powder has a lamellar structure at the microscopic level, can form a physical cross-linked network in the PP matrix, and is easily oriented and arranged under the action of shear force to form a reinforcing network, thereby significantly improving rigidity and strength. At the same time, adding a small amount of recycled silica powder to the filling masterbatch can improve the fluidity of the material, because silica powder is an inorganic nucleating agent, which can improve the mechanical properties of polypropylene and accelerate the crystallization of polypropylene. At the same time, silica powder has a spherical structure, which can play the role of a lubricant and improve the dispersibility of the additive in the composite material.

[0062] Combining Comparative Example 3 and Example 1, it can be seen that compared with the direct physical blending modification process of various processing aids and raw resins, first preparing the filling masterbatch and then blending it with the raw resin not only improves the dispersibility of the additives, but also promotes the uniformity of the material during the blending process, thereby achieving a better modification effect.

[0063] In summary, the recycled polypropylene reinforced toughening masterbatch and the preparation method thereof provided by the present invention have the following beneficial effects:

[0064] The beneficial effects of the present invention are:

[0065] 1. The present invention simplifies the auxiliary agent mixing process: the masterbatch and the resin particle size are very close, and the ingredients only need to be simply mixed.

[0066] 2. The present invention improves the dispersibility of the additive: the carrier layer selected for the masterbatch is a high-fluidity recycled polypropylene with a melt index of >50g / min, which is beneficial to the uniformity of the dispersion of the additive in the resin, so that the additive can give full play to its performance.

[0067] 3. The present invention utilizes recycled polyethylene resin, recycled thermoplastic polyolefin elastomer, talcum powder, recycled silica powder, and compatibilizer to form core-shell structure particles with talcum powder and recycled silica powder as hard core and recycled polyethylene resin and recycled thermoplastic polyolefin elastomer as soft shell. This structure effectively combines the rigidity and toughness of the additives.

[0068] 4. The main function of filling masterbatch is to reduce the cost of products and appropriately improve certain properties of products, such as rigidity and toughness. Using filling masterbatch can increase the amount of filler added to the resin, and the performance is improved compared to directly adding fillers.

[0069] The above-described embodiments merely represent several implementation manners of the present invention. The description thereof is relatively specific and detailed, but it should not be construed as a limitation on the scope of the patent for the present invention. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all fall within the protection scope of the present invention. Therefore, the protection scope of the patent for the present invention shall be subject to the appended claims.

Claims

1. A recycled polypropylene reinforced and toughened masterbatch, characterized in that: The invention comprises the following components by weight: 10-45 parts of high-fluidity recycled polypropylene resin, 5-10 parts of recycled polyethylene resin, 5-10 parts of recycled thermoplastic polyolefin elastomer, 30-50 parts of talc powder, 10-20 parts of recycled silicon dioxide powder, 0.1-10 parts of compatibilizer, 0.1-5 parts of dispersant and 0.1-5 parts of antioxidant.

2. The recycled polypropylene reinforced and toughened masterbatch according to claim 1, characterized in that: The high-fluidity recycled polypropylene resin is made by crushing, washing and drying the polypropylene plastic of scrapped washing machines. The main components are homopolymer polypropylene, calcium carbonate inorganic filler and color powder. The melt index is 40-60g / min and the cantilever beam notched impact strength is 3-6KJ / m 2 .

3. The recycled polypropylene reinforced and toughened masterbatch according to claim 1, characterized in that: The recycled polyethylene resin is obtained by recycling and crushing plastic pipes, and its main components are high-density polyethylene, calcium carbonate, toner pigments and processing aids, with a melt index of 3-8g / min and an Izod notched impact strength of 40-60KJ / m 2 .

4. The recycled polypropylene reinforced and toughened masterbatch according to claim 1, characterized in that: The recycled thermoplastic polyolefin elastomer is obtained by crushing and processing recycled toy materials, and is a combination of one or more of TPE, TPR, TPV, TPU, and TPO.

5. The recycled polypropylene reinforced and toughened masterbatch according to claim 1, characterized in that: The talcum powder is in a lamellar structure with a mesh size of 1000-3000 meshes.

6. The recycled polypropylene reinforced and toughened masterbatch according to claim 1, characterized in that: The recycled silicon dioxide powder is in a spherical structure with a mesh size of 500-1500 meshes.

7. The recycled polypropylene reinforced and toughened masterbatch according to claim 1, characterized in that: The compatibilizer is a combination of one or more of PE-g-ST, PP-g-ST, ABS-g-MAH, PE-g-MAH, and PP-g-MAH.

8. The recycled polypropylene reinforced and toughened masterbatch according to claim 1, characterized in that: The dispersant is a combination of one or more of polyethylene wax, EBS, erucamide, paraffin and stearic acid.

9. The recycled polypropylene reinforced and toughened masterbatch according to claim 1, characterized in that: The antioxidant is a mixture of a phenolic antioxidant and a phosphate antioxidant.

10. The method for preparing the recycled polypropylene reinforced and toughened masterbatch according to any one of claims 1 to 9, characterized in that: The following steps are involved: (1) Weighing talcum powder and recovered silica powder, drying them in an oven at 100° C. for 4 h, and then taking them out and putting them into a sealed bag for later use to reduce the moisture content in the filler; (2) placing high-fluidity recycled polypropylene, recycled polyethylene resin, recycled thermoplastic polyolefin elastomer, talcum powder, recycled silica powder, compatibilizer, dispersant, and antioxidant in a high-speed mixer, mixing for 5-8 minutes to make them uniformly mixed, taking them out, placing them in a feeding hopper of a screw extruder, and setting a certain feeding rate to feed the materials from the feeding hopper; (3) setting the extrusion temperature of the screw extruder to 180-220° C. and the extrusion speed of the screw extruder to 200-500 rpm; (4) The mixture extruded by the screw extruder is cooled, pelletized, and dried to obtain the recycled polypropylene reinforced and toughened masterbatch.

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