A polymer compatibilizer, its preparation method and application

Abstract

The application provides a polymer compatilizer, a preparation method and application thereof, and raw materials of the polymer compatilizer include the following components in parts by weight: 90-100 parts of polyolefin, 0.5-5 parts of silane coupling agent, and 0.01-1 parts of initiator; the silane coupling agent includes a combination of at least two kinds of silane coupling agents containing double bonds. The polymer compatilizer is a solid particle at normal temperature, has the advantages of macromolecules being easy to blend and feed, has high reactivity, enhances the bonding effect on inorganic fillers, forms different coupling effects with inorganic fillers, and cooperatively improves the compatibility and interface bonding force between inorganic fillers and a polymer system, so that the reinforcement and toughening of plastic composites are realized. In the recycled PE composition containing the polymer compatilizer, the compatibility of recycled PE and inorganic fillers is good, the interface bonding force is strong, the mechanical properties of the PE composition are significantly improved, and the PE composition has excellent strength, toughness and impact resistance.

Description

Technical Field

[0001] This invention belongs to the field of polymer materials technology, specifically relating to a polymer compatibilizer, its preparation method, and its application. Background Technology

[0002] Recycling and reusing plastics is an important way to solve current environmental problems. In the use of recycled plastics, to achieve reinforcement, toughening, and cost reduction, they are often filled with powders such as calcium carbonate, fiber, and talc. However, the binding capacity between polymers and filler powders is limited. Therefore, adding coupling agents to the mixture is a common practice in the industry to improve the compatibility between the polymer and the filler powder.

[0003] Currently, commonly used coupling agents include maleic anhydride grafts or small molecule silane coupling agents. For example, CN107973954A discloses a reinforced modified recycled polyethylene material, which is made from the following components in parts by weight: 30-75 parts recycled polyethylene, 10-30 parts low-density polyethylene, 5-15 parts maleic anhydride grafted polypropylene wax, 10-25 parts medium-alkali glass fiber, 0.01-0.02 parts antioxidant, and 0.5-2 parts di-tert-butylperoxydiisopropylbenzene. Among them, the maleic anhydride grafted polypropylene wax gives the material a certain degree of polarity and reactivity, thereby improving the compatibility between polyethylene and glass fiber. CN107973955A discloses a high-toughness, low-cost polyethylene filler masterbatch and its preparation method. The components are as follows: 10-20 parts recycled polyethylene, 10-30 parts low-density polyethylene, 2-6 parts maleic anhydride-grafted polypropylene wax, 75-85 parts inorganic mineral filler, 1.5-1.7 parts 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane, 0.01-0.02 parts antioxidant, and 1.2-3 parts lubricant. This filler masterbatch expands the application range of recycled plastics and possesses good mechanical properties. Maleic anhydride-grafted polypropylene wax and other maleic anhydride grafts are easily and uniformly blended with plastic particles in polymer systems. However, maleic anhydride has low reactivity with inorganic fillers, failing to effectively solve the interfacial compatibility problem between plastic particles and inorganic fillers, resulting in limited improvement in mechanical properties.

[0004] CN107418025A discloses a calcium carbonate-reinforced and toughened composite material for recycled high-density polyethylene (HDPE). Its raw material components include: 10-50 parts calcium carbonate, 50-90 parts recycled HDPE, 0.1-2 parts silane coupling agent, 1-30 parts maleic anhydride-grafted polyethylene, 0.1-2 parts oxidized polyethylene wax, and 0.1-2 parts antioxidant. This material exhibits good reinforcement and toughening effects on recycled HDPE. CN102863677A discloses a modified recycled polyethylene pipe and fitting material and its preparation method. Its components include: 5-55% polyethylene, 10-70% recycled polyethylene, 5-40% calcium carbonate, 5-40% talc, 0.5-3% silane coupling agent, as well as toughening agents, impact modifiers, dicumyl peroxide, antioxidant 1010, polyethylene wax, calcium stearate, and pigments. This material utilizes recycled polyethylene to replace new polyethylene, thereby alleviating the raw material and cost pressures associated with producing new polyethylene. Although silane coupling agents have good bonding effects on inorganic fillers, they are liquids, making operation complex, feeding inconvenient, and difficult to mix evenly with plastic particles, thus making it difficult to effectively promote the interfacial compatibility between plastic particles and inorganic fillers.

[0005] Therefore, developing a compatibilizer that is easy to mix and can effectively improve the compatibility between inorganic fillers and plastic particles is an urgent problem to be solved in this field. Summary of the Invention

[0006] To address the shortcomings of existing technologies, the present invention aims to provide a polymer compatibilizer, its preparation method, and its application. The polymer compatibilizer is a polyolefin graft, which has the advantages of easy blending and feeding of macromolecules, as well as high reactivity and strong bonding effect on inorganic fillers. It can effectively promote the interfacial compatibility and bonding between plastic particles and inorganic fillers, and is especially suitable for recycled polyethylene systems.

[0007] To achieve this objective, the present invention adopts the following technical solution:

[0008] In a first aspect, the present invention provides a polymer compatibilizer, wherein the raw materials for preparing the polymer compatibilizer comprise the following components in parts by weight:

[0009] 90-100 parts of polyolefin

[0010] 0.5-5 parts of silane coupling agent

[0011] Initiator 0.01-1 part;

[0012] The silane coupling agent comprises a combination of at least two (e.g., two, three, or four) silane coupling agents containing double bonds.

[0013] The polymer compatibilizer provided by this invention is obtained by reacting polyolefins and silane coupling agents in the presence of an initiator. At least two types of double-bonded silane coupling agents are grafted onto the polyolefin, resulting in a polymer compatibilizer that is a solid particle at room temperature, offering advantages such as easy blending and feeding of large molecules. Simultaneously, the polymer compatibilizer contains a large number of highly reactive silicon-oxygen bonds, enabling it to react and bind with inorganic fillers, effectively promoting interfacial compatibility and bonding between plastic particles and inorganic fillers, thereby strengthening and toughening the plastic system. Furthermore, the silane coupling agent comprises a combination of at least two (e.g., two, three, or four types) double-bonded silane coupling agents. Different double-bonded silane coupling agents grafted onto polyolefins exhibit different reactivity, resulting in variations in coupling and binding effects with the inorganic fillers. These different coupling forces synergistically enhance the bonding force between the polymer and the inorganic filler, leading to higher mechanical strength in the resulting polymer-inorganic filler composition.

[0014] In the polymer compatibilizer provided by the present invention, the amount of the polyolefin is 90-100 parts, for example, 91 parts, 92 parts, 93 parts, 94 parts, 95 parts, 96 parts, 97 parts, 98 parts or 99 parts, as well as specific values ​​between the above points. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0015] The amount of the silane coupling agent is 0.5-5 parts, for example, 0.8 parts, 1 part, 1.5 parts, 2 parts, 2.5 parts, 3 parts, 3.5 parts, 4 parts or 4.5 parts, as well as specific values ​​between the above points. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range, but preferably 1-4 parts.

[0016] The amount of the initiator is 0.01-1 part, for example, 0.05 parts, 0.1 parts, 0.2 parts, 0.3 parts, 0.4 parts, 0.5 parts, 0.6 parts, 0.7 parts, 0.8 parts or 0.9 parts, as well as specific values ​​between the above values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range, but 0.01-0.5 parts is preferred.

[0017] Preferably, the polyolefin includes any one or a combination of at least two of polyethylene, polypropylene, ethylene-vinyl acetate copolymer, ethylene-propylene copolymer, or ethylene-octene copolymer, with ethylene-octene copolymer (POE) being the most preferred.

[0018] Preferably, the polyethylene includes any one or a combination of at least two of high-density polyethylene, medium-density polyethylene, low-density polyethylene, linear low-density polyethylene, metallocene polyethylene, or ultra-low-density polyethylene.

[0019] Preferably, the polypropylene includes homopolymer polypropylene and / or copolymer polypropylene.

[0020] Preferably, the octene-based structural units in the ethylene-octene copolymer have a mass percentage content of 30-40%, for example, 31%, 32%, 33%, 34%, 35%, 36%, 37%, 38%, or 39%, as well as specific values ​​between the above values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0021] Preferably, the double-bonded silane coupling agent includes vinyl silane coupling agents and / or acryloyloxysilane coupling agents.

[0022] Preferably, the double-bonded silane coupling agent includes any one or a combination of at least two of vinyltrimethoxysilane, vinyltriethoxysilane, vinyltri(2-methoxyethoxy)silane, vinyltriisopropoxysilane, vinyltritert-butoxysilane, vinyltritert-butylperoxysilane, vinyltriacetoxysilane, or methacryloyloxypropyltrimethoxysilane.

[0023] Preferably, the silane coupling agent comprises a combination of a first silane coupling agent and a second silane coupling agent.

[0024] The first silane coupling agent is different from the second silane coupling agent, and each is independently selected from any one of vinyltrimethoxysilane, vinyltriethoxysilane, vinyltri(2-methoxyethoxy)silane, vinyltriisopropoxysilane, vinyltritert-butoxysilane, vinyltritert-butylperoxysilane, vinyltriacetoxysilane, or methacryloyloxypropyltrimethoxysilane.

[0025] Preferably, the mass ratio of the first silane coupling agent to the second silane coupling agent is 1:(0.5-1.5), for example, it can be 1:0.6, 1:0.7, 1:0.8, 1:0.9, 1:1, 1:1.1, 1:1.2, 1:1.3 or 1:1.4, etc.

[0026] As a preferred embodiment of the present invention, the mass ratio of the first silane coupling agent containing double bonds to the second silane coupling agent is 1:(0.5-1.5), so that the polymer compatibilizer contains a suitable proportion of silicon-oxygen bonds with different reactivity, which forms different coupling effects with the inorganic filler. The two work synergistically to further enhance the interfacial compatibility and bonding force between the inorganic filler and the polymer (plastic particles), thereby improving the mechanical properties of the polymer-inorganic filler composition. If the mass difference between the first silane coupling agent and the second silane coupling agent is too large, exceeding the range of 1:(0.5-1.5), it will affect the synergistic effect of the silicon-oxygen bonds with different reactivity, thereby reducing the compatibility and mechanical properties of the polymer-inorganic filler composition.

[0027] Preferably, the initiator is an organic peroxide.

[0028] Preferably, the initiator comprises any one or a combination of at least two of the following: dicumyl peroxide, bis(tert-butylperoxy)-3-hexyne, 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane, benzoyl peroxide, tert-butyl peroxide, or tert-butyl peroxide-2-ethylhexyl carbonate.

[0029] Preferably, the raw materials for preparation further include 0.1-1 parts by weight of antioxidant, for example, the antioxidant can be 0.2 parts, 0.3 parts, 0.4 parts, 0.5 parts, 0.6 parts, 0.7 parts, 0.8 parts or 0.9 parts, and specific values ​​between the above values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range, and 0.1-0.6 parts is further preferred.

[0030] Preferably, the antioxidant includes hindered phenolic antioxidants and / or phosphite antioxidants.

[0031] Preferably, the antioxidant comprises any one or a combination of at least two of the following: pentaerythritol tetrakis(β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate (antioxidant 1010), octadecyl β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate (antioxidant 1076), or tris(2,4-di-tert-butylphenyl) phosphite (antioxidant 168).

[0032] Preferably, the raw materials for preparation further include 0.1-1 parts of lubricant by weight. For example, the lubricant can be 0.2 parts, 0.3 parts, 0.4 parts, 0.5 parts, 0.6 parts, 0.7 parts, 0.8 parts, or 0.9 parts, as well as specific values ​​between the above values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range, but 0.3-0.8 parts is further preferred.

[0033] Preferably, the lubricant includes any one or a combination of at least two of fatty acid soap salt lubricants, silicone lubricants, or low molecular weight wax lubricants.

[0034] As a preferred embodiment of the present invention, the raw materials for preparing the polymer compatibilizer include the following components in parts by weight:

[0035]

[0036] In a second aspect, the present invention provides a method for preparing a polymer compatibilizer as described in the first aspect, the method comprising: mixing a polyolefin and an initiator to obtain a mixture; reacting the mixture with a silane coupling agent to obtain the polymer compatibilizer.

[0037] Preferably, the mixing is carried out in a mixer.

[0038] Preferably, the mixture further includes antioxidants and / or lubricants.

[0039] Preferably, the reaction temperature is 150-250℃, for example, it can be 160℃, 170℃, 180℃, 190℃, 200℃, 210℃, 220℃, 230℃ or 240℃, as well as specific values ​​between the above points. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0040] Preferably, the reaction is carried out in a screw extruder.

[0041] Preferably, the screw extruder includes a single-screw extruder or a twin-screw extruder (co-rotating twin-screw extruder or counter-rotating twin-screw extruder).

[0042] Preferably, the screw speed of the screw extruder is 250-350 rpm, for example, it can be 260 rpm, 270 rpm, 280 rpm, 290 rpm, 300 rpm, 310 rpm, 320 rpm, 330 rpm or 340 rpm, as well as specific values ​​between the above points. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0043] Preferably, the screw of the screw extruder has a length-to-diameter ratio > 40, for example, it can be 42, 44, 46, 48, 50, 52, 54, 56, 58 or 60, and more preferably 44-56.

[0044] Preferably, the residence time of the melt in the screw during the reaction is 30-90s, for example, it can be 35s, 40s, 45s, 50s, 55s, 60s, 65s, 70s, 75s, 80s or 85s, as well as specific values ​​between the above values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0045] Preferably, the extrusion temperature of the screw extruder is 150-250℃, for example, it can be 160℃, 170℃, 180℃, 190℃, 200℃, 210℃, 220℃, 230℃ or 240℃, as well as specific values ​​between the above points. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0046] Preferably, the temperature of the screw extruder is 150-200℃ in zone 1, 160-210℃ in zones 2-3, 195-215℃ in zones 4-6, 200-220℃ in zones 7-10, 190-210℃ in zones 11-12, and 180-200℃ in zone 13.

[0047] Preferably, the reaction is followed by a granulation step.

[0048] Preferably, the preparation method specifically includes: mixing polyolefin, initiator, antioxidant and lubricant evenly to obtain a mixture; the mixture and silane coupling agent are melt-reacted in a screw extruder, and then extruded and granulated to obtain the polymer compatibilizer; the temperature of the melt reaction is 150-250℃, the screw speed is 250-350rpm, and the residence time of the melt is 30-90s.

[0049] Thirdly, the present invention provides a polyethylene composition comprising a combination of polyethylene (PE), filler, and polymer compatibilizer as described in the first aspect.

[0050] Preferably, the polyethylene includes recycled polyethylene.

[0051] Preferably, the packing material comprises inorganic packing material.

[0052] Preferably, the inorganic filler includes any one or a combination of at least two of calcium carbonate, talc, titanium dioxide, glass fiber, or silica.

[0053] Preferably, the polyethylene composition comprises, by weight, the following components:

[0054] 40-60 parts of recycled polyethylene

[0055] 30-50 parts of inorganic filler

[0056] 1-5 parts of polymer compatibilizer.

[0057] The mass of the recycled polyethylene is 40-60 parts, for example, 41 parts, 43 parts, 45 parts, 47 parts, 49 parts, 50 parts, 51 parts, 53 parts, 55 parts, 57 parts or 59 parts, as well as specific values ​​between the above values. Due to space limitations and for the sake of brevity, this invention will not exhaustively list the specific values ​​included in the range.

[0058] The mass of the inorganic filler is 30-50 parts, for example, it can be 31 parts, 33 parts, 35 parts, 37 parts, 39 parts, 40 parts, 41 parts, 43 parts, 45 parts, 47 parts or 49 parts, as well as specific values ​​between the above values. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0059] The polymer compatibilizer is 1-5 parts by mass, for example, 1.2 parts, 1.5 parts, 1.8 parts, 2 parts, 2.2 parts, 2.5 parts, 2.8 parts, 3 parts, 3.2 parts, 3.5 parts, 3.8 parts, 4 parts, 4.2 parts, 4.5 parts, or 4.8 parts, as well as specific values ​​between the above values. Due to space limitations and for the sake of brevity, this invention will not exhaustively list the specific values ​​included in the range.

[0060] Preferably, the polyethylene composition further comprises 0.1-5 parts by weight of lubricant, for example, the lubricant may be 0.5 parts, 0.8 parts, 1 part, 1.5 parts, 2 parts, 2.5 parts, 3 parts, 3.5 parts, 4 parts or 4.5 parts, and specific values ​​between the above points. Due to space limitations and for the sake of brevity, the present invention will not exhaustively list the specific values ​​included in the range.

[0061] Preferably, the lubricant comprises any one or a combination of at least two of stearic acid, stearate, or PE wax.

[0062] Compared with the prior art, the present invention has the following beneficial effects:

[0063] (1) The polymer compatibilizer provided by the present invention grafts at least two double-bonded silane coupling agents with polyolefins, so that the polymer compatibilizer is a solid particle at room temperature. It has the advantages of easy mixing, feeding and dispersion of macromolecules, and also has high reactivity, which enhances the bonding effect on inorganic fillers and forms different coupling effects with inorganic fillers. It synergistically improves the compatibility and interfacial bonding force between inorganic fillers and polymer system, thereby realizing the reinforcement and toughening of plastic composite materials, especially suitable for recycled PE compositions.

[0064] (2) In the recycled PE composition containing the polymer compatibilizer, the recycled PE has good compatibility with the inorganic filler and strong interfacial bonding, which significantly improves the mechanical properties of the PE composition, with an impact strength ≥21kJ / m. 2 It has a tensile strength >24MPa, a flexural strength ≥35MPa, an elongation at break of over 17%, and a flexural modulus of 1830-2010MPa, exhibiting excellent strength, toughness, and impact resistance. Detailed Implementation

[0065] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be construed as limiting the invention in any way.

[0066] The materials involved in the following specific embodiments of the present invention include:

[0067] (1) Polyolefin: Ethylene-octene copolymer (POE elastomer), grade 8150, purchased from Dow Chemical Company;

[0068] (2) Silane coupling agents: vinyltrimethoxysilane, vinyltriethoxysilane, vinyltritert-butoxysilane, vinyltri(2-methoxyethoxy)silane;

[0069] (3) Initiator: 2,5-dimethyl-2,5-bis(tert-butylperoxide)hexane (bis25 initiator);

[0070] (4) Antioxidants: Antioxidant 168, Antioxidant 1010;

[0071] (5) Lubricant: silicone powder.

[0072] Example 1

[0073] A polymer compatibilizer, the raw materials for which are prepared include the following components in parts by weight:

[0074]

[0075] The silane coupling agent comprises a combination of vinyltrimethoxysilane and vinyltriethoxysilane in a mass ratio of 1:1; the antioxidant comprises a combination of antioxidant 168 and antioxidant 1010 in a mass ratio of 1:1.

[0076] The preparation method of the polymer compatibilizer includes the following steps:

[0077] (1) The POE elastomer, initiator, antioxidant and lubricant are dry-mixed evenly to obtain a mixture;

[0078] (2) The mixture obtained in step (1) is fed into a twin-screw extruder, and the silane coupling agent is injected from the side through a solution pump. The temperatures of each zone in the twin-screw extruder are 150℃, 170℃, 190℃, 200℃, 210℃, 210℃, 210℃, 210℃, 210℃, 210℃, 200℃, respectively. The length-to-diameter ratio of the twin screw is 48, the screw speed is 310 rpm, and the residence time of the melt in the screw is about 60 s. After the mixture and the silane coupling agent undergo a melt grafting reaction, the mixture is extruded and pelletized to obtain the polymer compatibilizer.

[0079] Example 2

[0080] A polymer compatibilizer, the raw materials for which are prepared include the following components in parts by weight:

[0081]

[0082] The silane coupling agent comprises a combination of vinyltrimethoxysilane and vinyltritert-butoxysilane in a mass ratio of 1:1; the antioxidant comprises a combination of antioxidant 168 and antioxidant 1010 in a mass ratio of 1:1; the preparation method of the polymer compatibilizer is the same as in Example 1.

[0083] Example 3

[0084] A polymer compatibilizer, the raw materials for which are prepared include the following components in parts by weight:

[0085]

[0086] The silane coupling agent comprises a combination of vinyltriethoxysilane and vinyltritert-butoxysilane in a mass ratio of 1:1; the antioxidant comprises a combination of antioxidant 168 and antioxidant 1010 in a mass ratio of 1:1; the preparation method of the polymer compatibilizer is the same as in Example 1.

[0087] Example 4

[0088] A polymer compatibilizer, the raw materials for which are prepared include the following components in parts by weight:

[0089]

[0090] The silane coupling agent comprises a combination of vinyltris(2-methoxyethoxy)silane and vinyltrimethoxysilane in a mass ratio of 1:1.5; the antioxidant comprises a combination of antioxidant 168 and antioxidant 1010 in a mass ratio of 1:1; the preparation method of the polymer compatibilizer is the same as in Example 1.

[0091] Example 5

[0092] A polymer compatibilizer, the raw materials for which are prepared include the following components in parts by weight:

[0093]

[0094] The silane coupling agent comprises a combination of vinyltritert-butoxysilane and vinyltrimethoxysilane in a mass ratio of 1:2; the antioxidant comprises a combination of antioxidant 168 and antioxidant 1010 in a mass ratio of 1:1; the preparation method of the polymer compatibilizer is the same as in Example 1.

[0095] Example 6

[0096] A polymer compatibilizer, the raw materials for which are prepared include the following components in parts by weight:

[0097]

[0098]

[0099] The silane coupling agent comprises a combination of vinyltrimethoxysilane and vinyltriethoxysilane in a mass ratio of 1:3; the antioxidant comprises a combination of antioxidant 168 and antioxidant 1010 in a mass ratio of 1:1; the preparation method of the polymer compatibilizer is the same as in Example 1.

[0100] Comparative Preparation Example 1

[0101] A polymer compatibilizer, the raw materials for which are prepared include the following components in parts by weight:

[0102]

[0103] The antioxidant comprises a combination of antioxidant 168 and antioxidant 1010 in a mass ratio of 1:1; the preparation method of the polymer compatibilizer is the same as in Example 1.

[0104] Comparative Preparation Example 2

[0105] A polymer compatibilizer, the raw materials for which are prepared include the following components in parts by weight:

[0106]

[0107] The antioxidant comprises a combination of antioxidant 168 and antioxidant 1010 in a mass ratio of 1:1; the preparation method of the polymer compatibilizer is the same as in Example 1.

[0108] Comparative preparation example 3

[0109] A polymer compatibilizer, the raw materials for which are prepared include the following components in parts by weight:

[0110]

[0111] The antioxidant comprises a combination of antioxidant 168 and antioxidant 1010 in a mass ratio of 1:1; the preparation method of the polymer compatibilizer is the same as in Example 1.

[0112] Application Example 1

[0113] A recycled PE composition comprising, by weight, the following components:

[0114]

[0115] The recycled polyethylene is mainly high-density polyethylene (HDPE); the compatibilizer is the polymer compatibilizer provided in Example 1.

[0116] The PE composition is prepared as follows: after mixing each component evenly according to the formula amount, it is added from the main feed port of a twin-screw extruder. The twin-screw extruder rotates at 300 rpm and the reaction zone temperature is 200℃. The mixture is then extruded and granulated to obtain the PE composition.

[0117] Application Example 2-6, Comparative Example 1-3

[0118] A recyclable PE composition differs from Application Example 1 only in that the compatibilizer is the polymer compatibilizer provided in Examples 2-6 and Comparative Preparation Examples 1-3, respectively; the other components, dosages, and preparation methods are the same as in Application Example 1.

[0119] Comparative Example 4

[0120] A recycled PE composition differs from Application Example 1 only in that it does not contain a compatibilizer and the mass of recycled polyethylene is 58 parts; the other components, amounts, and preparation methods are the same as in Application Example 1.

[0121] Comparative Example 5

[0122] A recycled PE composition comprising, by weight, the following components:

[0123]

[0124] The silane coupling agent comprises a combination of vinyltrimethoxysilane and vinyltriethoxysilane in a mass ratio of 1:1; the initiator is a bis25 initiator.

[0125] The PE composition is prepared as follows: after mixing each component evenly according to the formula amount, it is added from the main feed port of a twin-screw extruder. The twin-screw extruder rotates at 300 rpm and the reaction zone temperature is 200℃. The mixture is then extruded and granulated to obtain the PE composition.

[0126] The performance of the PE compositions provided in corresponding use cases 1-6 and comparative examples 1-5 was tested using the following methods:

[0127] (1) Tensile properties: The tensile strength and elongation at break of the sample were tested in accordance with the standard ISO 527-2 "Plastics - Test for tensile properties". The strength test speed was 50 mm / min.

[0128] (2) Bending performance: The bending strength and bending modulus of the sample were tested according to the standard ISO 178 "Plastics - Determination of bending properties". The sample size was 80mm×10mm×4mm, the bending speed was 2mm / min, and the span was 64mm.

[0129] (3) Impact strength: The notched impact strength was tested according to the standard ISO 180 "Plastics - Determination of impact strength of cantilever beams". The sample size was 80mm×10mm×4mm and the notch depth was 2mm.

[0130] The test results are shown in Table 1:

[0131] Table 1

[0132]

[0133] According to the test results in Table 1, compared with Comparative Example 4 without compatibilizer, the PE compositions in Application Examples 1-6 containing the polymer compatibilizer described in this invention exhibit significantly improved mechanical properties, with an impact strength of 20.6-23.7 kJ / m. 2 The tensile strength is 23.5-28.3 MPa, the elongation at break is 16.5-19.5%, the flexural strength reaches 32.8-36.5 MPa, and the flexural modulus is 1830-2010 MPa, exhibiting excellent tensile, impact, and flexural properties. Furthermore, this invention uses two double-bonded silane coupling agents compounded in a specific ratio and melt-grafted with polyolefins, creating different coupling effects between the polymer compatibilizer and the inorganic filler, synergistically enhancing the interfacial compatibility between the inorganic filler and the polymer. Compared to Application Examples 1-5, Application Example 6 contains a significantly different ratio of the two double-bonded silane coupling agents in its polymer compatibilizer, affecting the effect of the silicon-oxygen bonds with different reactivity, thereby reducing the mechanical properties of the PE composition.

[0134] In the PE compositions of Comparative Examples 1-3, the polymer compatibilizer was obtained by grafting a vinyl silane coupling agent onto POE elastomer. Its bonding force with the inorganic filler was poor, resulting in a very limited strengthening and toughening effect of the PE composition. In Comparative Example 5, the vinyl silane coupling agent was directly blended with recycled PE. Since the vinyl silane coupling agent is a liquid, it is difficult to blend it evenly with the plastic particles. As a result, the interfacial compatibility problem between the polymer and the inorganic filler was not effectively solved, and the mechanical properties of the PE composition were poor.

[0135] The applicant declares that the present invention is illustrated by the above embodiments to demonstrate a polymer compatibilizer, its preparation method, and its application. However, the present invention is not limited to the above embodiments, i.e., it does not mean that the present invention must rely on the above embodiments to be implemented. Those skilled in the art should understand that any improvements to the present invention, equivalent substitutions of the raw materials of the product of the present invention, addition of auxiliary components, and selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A polymer compatibilizer, characterized in that, The raw materials for preparing the polymer compatibilizer consist of the following components in parts by weight: 90-100 parts of polyolefin 0.5-5 parts of silane coupling agent Initiator 0.01-1 part Antioxidant 0.1-1 part Lubricant 0.1-1 part; The silane coupling agent includes a combination of a first silane coupling agent and a second silane coupling agent; The first silane coupling agent is different from the second silane coupling agent, and each is independently selected from any one of vinyltrimethoxysilane, vinyltriethoxysilane, vinyltri(2-methoxyethoxy)silane, vinyltriisopropoxysilane, vinyltritert-butoxysilane, vinyltritert-butylperoxysilane, vinyltriacetoxysilane, or methacryloxypropyltrimethoxysilane; The mass ratio of the first silane coupling agent to the second silane coupling agent is 1:(0.5-1.5); The polymer compatibilizer is prepared by the following method, which includes the following steps: A mixture of polyolefin, initiator, antioxidant and lubricant is obtained; the mixture is then reacted with a silane coupling agent to obtain the polymer compatibilizer.

2. The polymer compatibilizer according to claim 1, characterized in that, The polyolefin includes any one or a combination of at least two of polyethylene, polypropylene, ethylene-vinyl acetate copolymer, ethylene-propylene copolymer, or ethylene-octene copolymer.

3. The polymer compatibilizer according to claim 2, characterized in that, The polyolefin is an ethylene-octene copolymer.

4. The polymer compatibilizer according to claim 3, characterized in that, The ethylene-octene copolymer contains 30-40% by mass of octene-based structural units.

5. The polymer compatibilizer according to claim 1, characterized in that, The initiator is an organic peroxide.

6. The polymer compatibilizer according to claim 1, characterized in that, The initiator includes any one or a combination of at least two of the following: dicumyl peroxide, bis(tert-butylperoxy)-3-hexyne, 2,5-dimethyl-2,5-bis(tert-butylperoxy)-3-hexyne, 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane, benzoyl peroxide, tert-butyl peroxide, or tert-butyl peroxy-2-ethylhexyl carbonate.

7. The polymer compatibilizer according to claim 1, characterized in that, The antioxidants include hindered phenolic antioxidants and / or phosphite antioxidants.

8. The polymer compatibilizer according to claim 1, characterized in that, The antioxidant includes any one or a combination of at least two of the following: pentaerythritol tetrakis(β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate), octadecyl β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, or tris(2,4-di-tert-butylphenyl)phosphite.

9. The polymer compatibilizer according to claim 1, characterized in that, The lubricant includes any one or a combination of at least two of fatty acid soap salt lubricants, silicone lubricants, or low molecular weight wax lubricants.

10. A method for preparing a polymer compatibilizer as described in any one of claims 1-9, characterized in that, The preparation method includes: mixing a polyolefin and an initiator to obtain a mixture; reacting the mixture with a silane coupling agent to obtain the polymer compatibilizer; The mixture also includes antioxidants and lubricants.

11. The preparation method according to claim 10, characterized in that, The reaction temperature is 150-250℃.

12. The preparation method according to claim 10, characterized in that, The reaction is carried out in a screw extruder.

13. The preparation method according to claim 12, characterized in that, The screw speed of the screw extruder is 250-350 rpm.

14. The preparation method according to claim 10, characterized in that, The residence time of the melt in the screw during the reaction is 30-90 s.

15. The preparation method according to claim 10, characterized in that, The reaction is followed by a granulation step.

16. The preparation method according to claim 10, characterized in that, The preparation method specifically includes: mixing polyolefin, initiator, antioxidant and lubricant evenly to obtain a mixture; the mixture and silane coupling agent are melt-reacted in a screw extruder, and then extruded and granulated to obtain the polymer compatibilizer; the temperature of the melt reaction is 150-250℃, the screw speed is 250-350 rpm, and the residence time of the melt is 30-90 s.

17. A polyethylene composition, characterized in that, The polyethylene composition comprises a combination of polyethylene, filler, and polymer compatibilizer as described in any one of claims 1-9.

18. The polyethylene composition according to claim 17, characterized in that, The polyethylene includes recycled polyethylene.

19. The polyethylene composition according to claim 17, characterized in that, The packing material includes inorganic packing material.

20. The polyethylene composition according to claim 17, characterized in that, The polyethylene composition comprises the following components in parts by weight: 40-60 parts of recycled polyethylene 30-50 parts of inorganic filler 1-5 parts of polymer compatibilizer.

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