Polyolefin thermoplastic elastomer / silicone rubber thermoplastic vulcanized rubber and preparation method and application thereof

Abstract

The invention relates to the technical field of high polymer materials, in particular to polyolefin thermoplastic elastomer / silicone rubber thermoplastic vulcanized rubber as well as a preparation method and application thereof. According to the invention, the polyolefin thermoplastic elastomer grafted silane or / and the polyolefin thermoplastic elastomer grafted maleic anhydride / glycidyl ester terpolymer, the platinum catalyst and the inhibitor are added during blending and dynamic vulcanization of the silicone rubber and the polyolefin thermoplastic elastomer to regulate and control the dynamic vulcanization process; therefore, the thermoplastic vulcanized rubber with ideal mechanical properties is obtained. The polyolefin thermoplastic elastomer / silicone rubber thermoplastic vulcanizate provided by the invention is high in strength, good in elasticity, good in toughness, smooth in surface, fine in phase state, good in somatosensory compatibility and good in skin touch, and also has good stain resistance, sweat resistance, yellowing resistance and ultraviolet resistance.

Description

Technical Field

[0001] The present invention relates to the technical field of polymer materials. Further, it relates to a polyolefin thermoplastic elastomer / silicone rubber thermoplastic vulcanizate and its preparation method and application. Background Art

[0002] Silicone rubber (SiR), such as dimethyl silicone rubber (DMQ), methyl vinyl silicone rubber (MVQ), and methyl vinyl phenyl silicone rubber (MVPQ), has a main chain structure composed of highly flexible Si-O-Si bonds, and groups such as methyl, vinyl, or phenyl are attached to Si atoms. Therefore, its physical and chemical properties combine organic and inorganic characteristics. Due to the unique molecular structure of silicone rubber (SiR), it has high elasticity in a wide temperature range, excellent aging resistance, dielectric, and thermal stability, and is widely used in various industrial fields such as medical devices, the aerospace industry, the automotive industry, and intelligent wearable devices.

[0003] Polyolefin thermoplastic elastomer (POE) is a random copolymer with a high α-olefin content obtained by copolymerizing ethylene and α-olefins (such as 1-octene, 1-hexene, 1-butene, etc.). In POE, α-olefins are introduced into the polymer chain in a random form, disrupting the crystalline structure of polyethylene, thereby forming an elastic amorphous region (rubber phase); while the undamaged polyethylene chain segments maintain crystallinity, forming a crystalline region (plastic phase) with physical crosslinking ability. Due to the physical crosslinking (crystallization) structure being stable at room temperature and being able to be disrupted at temperatures above the melting point, POE maintains high elasticity of rubber at room temperature and is easily plasticized and molded at high temperatures. Therefore, POE is widely used in fields such as the automotive industry, packaging materials, photovoltaic cables, sports goods, and medical supplies.

[0004] Dynamic Vulcanization is an advanced process of shear blending rubber and thermoplastic plastics in a high-temperature molten state; during this process, the rubber is gradually vulcanized and continuously mixed with the thermoplastic plastic. Finally, the vulcanized rubber is uniformly distributed in the continuous thermoplastic plastic matrix in the form of a dispersed phase. The materials prepared by the dynamic vulcanization technology not only inherit the excellent elasticity of traditional rubber but also have good processing properties of thermoplastic plastics. This high-performance thermoplastic elastomer is usually called Thermoplastic Vulcanizate (TPV). Due to its unique microstructure and excellent comprehensive properties, TPV shows broad application prospects and important research value in multiple industrial fields.

[0005] However, when using silicone rubber and polyolefin thermoplastic elastomer as raw materials and preparing thermoplastic vulcanizate by dynamic vulcanization method, the following technical problems exist: it is difficult to obtain thermoplastic vulcanizate with fine phase morphology, and its mechanical properties, elastic properties and processing properties are not ideal either. Summary of the Invention

[0006] The technical problem to be solved by the present invention: for the thermoplastic vulcanizate prepared by using silicone rubber and polyolefin thermoplastic elastomer as raw materials and adopting the dynamic vulcanization method, the problem that its mechanical properties, elastic properties and processing properties are not ideal.

[0007] The present invention regulates the dynamic vulcanization process by adding polyolefin thermoplastic elastomer grafted silane or / and polyolefin thermoplastic elastomer grafted maleic anhydride / glycidyl acrylate terpolymer, platinum catalyst and inhibitor during the co-blending dynamic vulcanization of silicone rubber and polyolefin thermoplastic elastomer, thereby obtaining thermoplastic vulcanizate with ideal comprehensive properties.

[0008] One of the purposes of the present invention is to provide a polyolefin thermoplastic elastomer / silicone rubber thermoplastic vulcanizate (hereinafter may be abbreviated as TPV).

[0009] The polyolefin thermoplastic elastomer / silicone rubber thermoplastic vulcanizate is prepared by dynamic vulcanization from raw materials comprising the following components;

[0010] The components and their parts by weight are as follows:

[0011] The total of silicone rubber and polyolefin thermoplastic elastomer is 100 parts by weight;

[0012] The compatibilizer is 1-40 parts by weight, preferably 5-20 parts by weight;

[0013] The vulcanizing agent is 1-15 parts by weight, preferably 3-10 parts by weight;

[0014] The platinum catalyst is 0.1-3 parts by weight, preferably 0.1-1 part by weight;

[0015] The inhibitor is 0.1-6 parts by weight, preferably 0.3-2 parts by weight;

[0016] The antioxidant is 0.01-0.8 parts by weight, preferably 0.02-0.5 parts by weight;

[0017] The weight ratio of the silicone rubber to the polyolefin thermoplastic elastomer is (30-90):(70-10), preferably (50-80):(50-20);

[0018] The compatibilizer is compatibilizer A or compatibilizer B;

[0019] The compatibilizer A is polyolefin thermoplastic elastomer grafted silane;

[0020] The compatibilizer B is composed of a polyolefin thermoplastic elastomer grafted with maleic anhydride and an acid glycidyl ester terpolymer in a weight ratio of (3 - 4.5) : (2 - 0.5); preferably, the weight ratio of the polyolefin thermoplastic elastomer grafted with maleic anhydride to the acid glycidyl ester terpolymer is (3.5 - 4) : (1.5 - 1).

[0021] The silicone rubber (hereinafter may be abbreviated as SiR) can be any existing silicone rubber; preferably, it is a high-temperature vulcanized silicone rubber. The thermoplastic vulcanizate prepared by blending and dynamically vulcanizing the high-temperature vulcanized silicone rubber and the polyolefin thermoplastic elastomer in the present invention has better elasticity, lower hardness, and smoother surface. As a specific embodiment, the silicone rubber can be methyl vinyl silicone rubber, methyl vinyl phenyl silicone rubber, or fluorosilicone rubber respectively. Data shows that: using methyl vinyl silicone rubber for the next step of preparation, the properties of the obtained product are the best; therefore, the silicone rubber is more preferably methyl vinyl silicone rubber. The molecular weight of the silicone rubber is 5000 - 800000, preferably 550000 - 700000.

[0022] The polyolefin thermoplastic elastomer (Polyolefin Thermoplastic Elastomer; hereinafter may be abbreviated as POE) is a copolymer obtained by polymerizing ethylene or propylene as the main polymerization unit and α-olefins (such as 1-butene, 1-hexene, 1-octene, etc.) as comonomers under the action of a metallocene catalyst. Any existing polyolefin thermoplastic elastomer can be selected in the present invention. The molecular weight of the polyolefin thermoplastic elastomer matrix can affect the properties of the prepared TPV. As a preferred embodiment, the molecular weight of the polyolefin thermoplastic elastomer is 5000 - 500000, more preferably 15000 - 200000. As a specific embodiment, the molecular weight of the polyolefin thermoplastic elastomer is 100000 - 150000 or 150000 - 200000.

[0023] The vulcanizing agent can be any existing vulcanizing agent that can be used for the dynamic vulcanization of silicone rubber and polyolefin thermoplastic elastomer. As a preferred embodiment, the vulcanizing agent is hydrogen-containing silicone oil. As a more preferred embodiment, the content of active hydrogen in the hydrogen-containing silicone oil is 0.5 - 1.5 wt%, further preferably 0.6 - 0.8 wt%. The "active hydrogen" is the hydrogen on Si-H in the hydrogen-containing silicone oil.

[0024] The platinum catalyst can be any existing platinum catalyst that can be used for the dynamic vulcanization of silicone rubber and polyolefin thermoplastic elastomer. As a preferred embodiment, the platinum catalyst can be selected from liquid platinum catalysts, preferably at least one of isopropyl alcohol complexes of chloroplatinic acid, platinum catalysts coordinated with tetrahydrofuran, and platinum catalysts coordinated with methyl vinyl siloxane. The platinum catalyst can play a catalytic role in the vulcanization of silicone rubber.

[0025] The inhibitor is selected from at least one of alkynol inhibitors, azo inhibitors and heavy metal ion compounds, and more preferably alkynol inhibitors.

[0026] During the dynamic vulcanization process, if no inhibitor is added, when the catalytic system is introduced, SiR will crosslink rapidly and be completely crosslinked before forming a fine dispersion. The crosslinked SiR has too high a viscosity and is difficult to be broken and homogenized, resulting in the disadvantages of rough appearance and poor performance of the finally prepared thermoplastic vulcanizate. If an inhibitor is added, at room temperature, the inhibitor and the platinum catalyst form a complex. When added to the high-temperature rubber-plastic premix, the complex formed by the two decomposes under high-temperature conditions, and the platinum catalyst is released, causing SiR to crosslink; that is, the release of the catalyst is synchronized with the crosslinking reaction, effectively slowing down the crosslinking rate of SiR. This slowdown enables SiR to form a fine dispersed phase before complete crosslinking, thus significantly improving the apparent quality of the finally prepared TPV. Therefore, the role of the inhibitor in the present invention cannot be ignored. It not only effectively slows down the crosslinking rate without affecting the degree of crosslinking, but also promotes the uniform distribution of the degree of crosslinking.

[0027] The antioxidant can be any antioxidant that can be used for the dynamic vulcanization of silicone rubber and polyolefin thermoplastic elastomer. As a preferred solution, the antioxidant can be selected from at least one of hindered phenol antioxidants, phosphite antioxidants and thioester antioxidants, and more preferably hindered phenol antioxidants. The thioester antioxidants can be selected from one or more of dilauryl thiodipropionate, dioctadecyl thiodipropionate, etc.

[0028] In the raw material components of the polyolefin thermoplastic elastomer / silicone rubber thermoplastic vulcanizate of the present invention, the platinum catalyst and the inhibitor form a catalytic system; the vulcanizing agent (hydrogen-containing silicone oil) and the catalytic system (platinum catalyst and inhibitor) form a vulcanization system.

[0029] The present invention can also add various commonly used additives in the art according to processing needs, such as methyl silicone oil, etc. Their dosages are all conventional dosages, or can be adjusted according to the requirements of the actual situation.

[0030] The present invention uses polyolefin thermoplastic elastomer grafted with silane as a compatibilizer during the blending and dynamic vulcanization of silicone rubber and polyolefin thermoplastic elastomer. The polyolefin chain segment in the polyolefin thermoplastic elastomer grafted with silane has good compatibility with the POE phase through intermolecular physical entanglement, while the silane chain segment has good compatibility with the SiR phase through intermolecular physical entanglement. Therefore, the polyolefin thermoplastic elastomer grafted with silane as a compatibilizer can effectively improve the compatibility between SiR and POE, thereby obtaining a thermoplastic vulcanizate with ideal mechanical properties.

[0031] The present invention uses a composition composed of a polyolefin thermoplastic elastomer grafted with maleic anhydride and a glycidyl acrylate terpolymer in a weight ratio of (3 - 4.5):(2 - 0.5) as a compatibilizer during the dynamic vulcanization of the blend of silicone rubber and polyolefin thermoplastic elastomer. The glycidyl acrylate terpolymer is an ethylene-methyl acrylate-glycidyl methacrylate terpolymer (EMA-co-GMA), and the α-carbon atom therein can be grafted onto the vinyl group of the silicone rubber to in-situ form EMA-g-PDMS rubber; the epoxy group in glycidyl methacrylate of the ethylene-methyl acrylate-glycidyl methacrylate terpolymer (EMA-co-GMA) will react in-situ with maleic anhydride to form a copolymer compatibilizer. The polyolefin segment of the polyolefin thermoplastic elastomer grafted with maleic anhydride or the polypropylene segment of polypropylene grafted with maleic anhydride in the copolymer compatibilizer has good compatibility with the POE phase through intermolecular physical entanglement, thereby improving the compatibility between the silicone rubber and the polyolefin thermoplastic elastomer.

[0032] In order to obtain thermoplastic vulcanizates with ideal mechanical properties, in addition to compatibilizers A and B, the present invention also conducted relevant experiments with compatibilizer C. Compatibilizer C is composed of polypropylene grafted with maleic anhydride and a glycidyl acrylate terpolymer in a weight ratio of (3 - 4.5):(2 - 0.5).

[0033] The α-carbon atom in the glycidyl acrylate terpolymer in compatibilizer C can be grafted onto the vinyl group of the silicone rubber to in-situ form EMA-g-PDMS rubber; the epoxy group in glycidyl methacrylate of the glycidyl acrylate terpolymer will react in-situ with maleic anhydride to form a copolymer compatibilizer. The polyolefin segment of the polyolefin thermoplastic elastomer grafted with maleic anhydride or the polypropylene segment of polypropylene grafted with maleic anhydride in the copolymer compatibilizer has good compatibility with the POE phase through intermolecular physical entanglement, thereby improving the compatibility between the two matrices.

[0034] Thus, it can be seen that the compatibilization mechanism of compatibilizer C is the same as that of compatibilizer B. In theory, compatibilizer C can also achieve a compatibilization effect and the compatibilization effect of compatibilizer C should be comparable to that of compatibilizer B. However, experiments have shown that the compatibilization effect of compatibilizer C is poor, significantly lower than that of compatibilizer A and compatibilizer B. Therefore, the present invention selects compatibilizer A and compatibilizer B as compatibilizers.

[0035] The second object of the present invention is to provide a preparation method of the polyolefin thermoplastic elastomer / silicone rubber thermoplastic vulcanizate described in the first object of the invention.

[0036] The preparation method of the polyolefin thermoplastic elastomer / silicone rubber thermoplastic vulcanizate includes the following steps:

[0037] (1) Mix the silicone rubber and vulcanizing agent evenly at room temperature to obtain a mixed rubber; mix the platinum catalyst and inhibitor evenly at room temperature to obtain a catalytic system;

[0038] (2) Rubber-plastic premixing: Mix the mixed rubber, polyolefin thermoplastic elastomer, compatibilizer and antioxidant evenly according to the described weight ratio or parts by weight to obtain a rubber-plastic premix;

[0039] (3) Dynamic vulcanization: Add the catalytic system to the rubber-plastic premix and perform dynamic vulcanization to obtain the silicone rubber / polyolefin thermoplastic elastomer thermoplastic vulcanizate;

[0040] Both the rubber-plastic premixing and dynamic vulcanization are carried out under the temperature condition of 130°C - 250°C; preferably, the dynamic vulcanization is carried out under the temperature condition of 190°C - 220°C.

[0041] The preparation method of the present invention adopts the rubber-plastic premixing - high-temperature sulfur addition - dynamic vulcanization method. After evenly mixing the silicone rubber and vulcanizing agent at room temperature, the rubber-plastic premixing is completed at high temperature, and then the premixed catalytic system is added to achieve dynamic vulcanization. This method can disperse the vulcanizing agent into the silicone rubber directionally at room temperature, which is more conducive to the dispersion of the silicone rubber in the POE matrix and improves the product performance.

[0042] The cross-linking method adopted by the present invention is the high-temperature sulfur addition method, that is, first melt and mix SiR, vulcanizing agent, POE, compatibilizer and antioxidant at high temperature, and then add the catalytic system to it to achieve the dynamic vulcanization of the silicone rubber under high temperature and high shear.

[0043] In the above preparation method, the rotor speed during the dynamic vulcanization process can be selected as the conventional speed. Data shows that: the rotor speed can affect the performance of the prepared TPV, and there is an optimal rotor speed to prepare the TPV with the best performance. Therefore, as a preferred scheme, the rotor speed during the dynamic vulcanization process is 80 rpm - 200 rpm, more preferably 160 rpm

[0044] The third object of the present invention is to provide the application of the polyolefin thermoplastic elastomer / silicone rubber thermoplastic vulcanizate described in the first object of the invention. The application of the polyolefin thermoplastic elastomer / silicone rubber thermoplastic vulcanizate in the fields of wearable skin-friendly devices and biomedical materials.

[0045] Compared with the prior art, the beneficial effects of the present invention:

[0046] The polyolefin thermoplastic elastomer / silicone rubber thermoplastic vulcanizate provided by the present invention has high strength, good elasticity, good toughness, smooth surface, fine phase state, has good body feeling compatibility, good skin touch, and at the same time has good stain resistance, sweat resistance, yellowing resistance and ultraviolet resistance.

[0047] The preparation method of the present invention prepares thermoplastic vulcanized rubber with good physical and mechanical properties, elastic properties and processing properties by blending SiR and POE, and adopting rubber and plastic premixing and dynamic vulcanization technology. The preparation method of the present invention is more convenient and quick, and is conducive to industrial application.

[0048] In the present invention, the room temperature refers to 23°C±5°C. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 The microscopic phase diagram of the polyolefin thermoplastic elastomer / silicone rubber thermoplastic vulcanizate TPV prepared in Example 1;

[0050] Figure 2 The stain resistance test results of the polyolefin thermoplastic elastomer / silicone rubber thermoplastic vulcanizate TPV prepared in Example 1;

[0051] Figure 3 These are the test results of the yellowing resistance and UV resistance of the polyolefin thermoplastic elastomer / silicone rubber thermoplastic vulcanizate TPV prepared in Example 1. DETAILED DESCRIPTION

[0052] The present invention is described in detail below in conjunction with specific embodiments. It is necessary to point out that the following embodiments are only used to further illustrate the present invention and cannot be understood as limiting the scope of protection of the present invention. Some non-essential improvements and adjustments made to the present invention by those skilled in the art based on the contents of the present invention still fall within the scope of protection of the present invention.

[0053] The raw materials used in the following examples and comparative examples are all commercially available products.

[0054] Methyl vinyl silicone rubber was from Dongjue Silicone Group Co., Ltd., brand 110-1s;

[0055] Methyl vinyl phenyl silicone rubber was from Shanghai Aishibo Silicone Materials Co., Ltd., brand ASIBO-129-1;

[0056] Fluorosilicone rubber comes from Wacker Chemical (China) Co., Ltd., brand ELASTOSIL R 901 / 60

[0057] The polyolefin thermoplastic elastomer was from The Dow Chemical Company, USA, brand 8150;

[0058] The polyolefin thermoplastic elastomer grafted silane was from Coase Chemical Co., Ltd., brand R1020;

[0059] Polyolefin thermoplastic elastomer grafted with maleic anhydride was from Coase Chemical Co., Ltd., brand W1F;

[0060] The polypropylene grafted maleic anhydride is from DuPont Company in the United States, with the grade P353;

[0061] The glycidyl methacrylate terpolymer is from Arkema Company in France, with the grade AX8900;

[0062] The hydrogen-containing silicone oil is from Zijun Chemical Co., Ltd., and the active hydrogen content is 0.8 wt%;

[0063] The platinum catalyst is a platinum catalyst coordinated with methyl vinyl siloxane from Zijun Chemical Co., Ltd., and the Pt content is: 100 - 10000 ppm;

[0064] The inhibitor is the alkynol M622 from Guangzhou Xiyou New Material Technology Co., Ltd.;

[0065] The antioxidant is antioxidant 1010 from BASF Co., Ltd.

[0066] Example 1

[0067] The selected raw materials and parts by weight are as follows:

[0068] 50 parts by weight of methyl vinyl silicone rubber (Mn = 600000);

[0069] 50 parts by weight of polyolefin thermoplastic elastomer (Mn = 150000);

[0070] 10 parts by weight of compatibilizer (polyolefin thermoplastic elastomer grafted with silane);

[0071] 6 parts by weight of hydrogen-containing silicone oil;

[0072] 0.4 parts by weight of platinum catalyst;

[0073] 1.2 parts by weight of inhibitor;

[0074] 0.1 parts by weight of antioxidant.

[0075] According to the above formula, the platinum catalyst and the inhibitor are mixed evenly at room temperature to obtain a catalytic system; using an open mill, the methyl vinyl silicone rubber and the hydrogen-containing silicone oil are blended evenly at room temperature to obtain a mixed rubber; the mixed rubber, the polyolefin thermoplastic elastomer, the compatibilizer and the antioxidant are

[0076] (200℃ / 160 rpm) fully mixed evenly (to obtain a rubber-plastic premix), and then under the same conditions (200℃ / 160 rpm), the catalytic system is added to the Haake mixer, and dynamic vulcanization is carried out at 200℃ / 160 rpm to obtain a polyolefin thermoplastic elastomer / silicone rubber thermoplastic vulcanizate TPV.

[0077] The TPV is pressed into a 2-mm-thick sheet according to the standard and the performance is tested. The test results are shown in Table 1.

[0078] Example 2

[0079] The raw materials selected and their parts by weight are as follows:

[0080] Methyl vinyl silicone rubber (Mn = 500,000): 60 parts by weight;

[0081] Polyolefin thermoplastic elastomer (Mn = 190,000): 40 parts by weight;

[0082] Compatibilizer (polyolefin thermoplastic elastomer grafted with silane): 10 parts by weight;

[0083] Hydrogen-containing silicone oil: 7 parts by weight;

[0084] Platinum catalyst: 0.5 part by weight;

[0085] Inhibitor: 1.5 parts by weight;

[0086] Antioxidant: 0.1 part by weight.

[0087] According to the above formula, the platinum catalyst and the inhibitor are mixed evenly at room temperature to obtain a catalytic system; using an open mill, the methyl vinyl silicone rubber and the hydrogen-containing silicone oil are blended evenly at room temperature to obtain a mixed rubber; the mixed rubber, the polyolefin thermoplastic elastomer, the compatibilizer and the antioxidant are placed in a Haake mixer

[0088] (220 °C / 120 rpm) and mixed evenly (to obtain a rubber-plastic premix), and then the catalytic system is added to the Haake mixer under the same conditions (220 °C / 120 rpm), and dynamic vulcanization is carried out at 220 °C / 120 rpm to obtain a polyolefin thermoplastic elastomer / silicone rubber thermoplastic vulcanizate TPV.

[0089] The TPV is pressed into a 2-mm-thick sheet according to the standard and its properties are tested. The test results are shown in Table 1.

[0090] Example 3

[0091] The raw materials selected and their parts by weight are as follows:

[0092] Methyl vinyl silicone rubber (Mn = 100,000): 60 parts by weight;

[0093] Polyolefin thermoplastic elastomer (Mn = 120,000): 40 parts by weight;

[0094] Compatibilizer (polyolefin thermoplastic elastomer grafted with silane): 5 parts by weight;

[0095] Hydrogen-containing silicone oil: 5 parts by weight;

[0096] Platinum catalyst: 0.5 part by weight;

[0097] Inhibitor: 1.5 parts by weight;

[0098] Antioxidant: 0.1 part by weight.

[0099] According to the above formula, the platinum catalyst and the inhibitor are mixed evenly at room temperature to obtain a catalytic system; using an open mill, the methyl vinyl silicone rubber and the hydrogen-containing silicone oil are blended evenly at room temperature to obtain a mixed rubber; the mixed rubber, the polyolefin thermoplastic elastomer, the compatibilizer and the antioxidant are fully mixed evenly in a Haake mixer (180 °C / 80 rpm) (to obtain a rubber-plastic premix), and then the catalytic system is added to the Haake mixer under the same conditions (180 °C / 80 rpm), and dynamic vulcanization is carried out at 180 °C / 80 rpm to obtain a polyolefin thermoplastic elastomer / silicone rubber thermoplastic vulcanizate TPV.

[0100] The TPV is pressed into a 2-mm-thick sheet according to the standard and its properties are tested. The test results are shown in Table 1.

[0101] Example 4

[0102] The raw materials selected and their parts by weight are as follows:

[0103] Methyl vinyl silicone rubber (Mn = 200000): 50 parts by weight;

[0104] Polyolefin thermoplastic elastomer (Mn = 150000): 50 parts by weight;

[0105] Compatibilizer (polyolefin thermoplastic elastomer grafted with silane): 15 parts by weight;

[0106] Hydrogen-containing silicone oil: 3 parts by weight;

[0107] Platinum catalyst: 0.2 part by weight;

[0108] Inhibitor: 0.6 part by weight;

[0109] Antioxidant: 0.1 part by weight.

[0110] According to the above formula, the platinum catalyst and the inhibitor are mixed evenly at room temperature to obtain a catalytic system; using an open mill, the methyl vinyl silicone rubber and the hydrogen-containing silicone oil are blended evenly at room temperature to obtain a mixed rubber; the mixed rubber, the polyolefin thermoplastic elastomer, the compatibilizer and the antioxidant are fully mixed evenly in a Haake mixer

[0111] (230 °C / 120 rpm) (to obtain a rubber-plastic premix), and then the catalytic system is added to the Haake mixer under the same conditions (230 °C / 120 rpm), and dynamic vulcanization is carried out at 230 °C / 120 rpm to obtain a polyolefin thermoplastic elastomer / silicone rubber thermoplastic vulcanizate TPV.

[0112] The TPV is pressed into a 2-mm-thick sheet according to the standard and its properties are tested. The test results are shown in Table 1.

[0113] Example 5

[0114] The raw materials selected and their parts by weight are the same as those in Example 1, but the rotational speed of the mixer rotor is changed to 80 rpm, and TPV is prepared by dynamic vulcanization using the same method and process parameters as in Example 1.

[0115] The TPV is pressed into a 2-mm-thick sheet according to the standard and its properties are tested. The test results are shown in Table 1.

[0116] Example 6

[0117] The raw materials selected and their parts by weight are the same as those in Example 1, but the rotational speed of the mixer rotor is changed to 200 rpm, and TPV is prepared by dynamic vulcanization using the same method and process parameters as in Example 1.

[0118] The TPV is pressed into a 2-mm-thick sheet according to the standard and its properties are tested. The test results are shown in Table 1.

[0119] Example 7

[0120] The raw materials selected and their parts by weight are the same as those in Example 1, but the molecular weight of the polyolefin thermoplastic elastomer is changed to (Mn = 50000), and TPV is prepared by dynamic vulcanization using the same method and process parameters as in Example 1.

[0121] The TPV is pressed into a 2-mm-thick sheet according to the standard and its properties are tested. The test results are shown in Table 1.

[0122] Example 8

[0123] The raw materials selected and their parts by weight are the same as those in Example 1, but the molecular weight of the polyolefin thermoplastic elastomer is changed to (Mn = 250000), and TPV is prepared by dynamic vulcanization using the same method and process parameters as in Example 1.

[0124] The TPV is pressed into a 2-mm-thick sheet according to the standard and its properties are tested. The test results are shown in Table 1.

[0125] Example 9

[0126] The raw materials selected and their parts by weight are the same as those in Example 2, but the methyl vinyl silicone rubber is replaced with methyl vinyl phenyl silicone rubber (Mn = 500000), and TPV is prepared by dynamic vulcanization using the same method and process parameters as in Example 2.

[0127] The TPV is pressed into a 2-mm-thick sheet according to the standard and its properties are tested. The test results are shown in Table 1.

[0128] Example 10

[0129] The raw materials selected and their weight parts are the same as those in Example 2, but the methyl vinyl silicone rubber is replaced with fluorosilicone rubber (Mn = 200,000), and a thermoplastic vulcanizate (TPV) is prepared by dynamic vulcanization using the same method and process parameters as in Example 2.

[0130] The TPV is pressed into a 2-mm-thick sheet according to the standard and its properties are tested. The test results are shown in Table 1.

[0131] Example 11

[0132] The raw materials selected and their weight parts are as follows:

[0133] 60 parts by weight of methyl vinyl silicone rubber (Mn = 600,000);

[0134] 40 parts by weight of polyolefin thermoplastic elastomer (Mn = 150,000);

[0135] 8 parts by weight of compatibilizer (polyolefin thermoplastic elastomer grafted maleic anhydride);

[0136] 2 parts by weight of compatibilizer (glycidyl acrylate terpolymer);

[0137] 7 parts by weight of hydrogen-containing silicone oil;

[0138] 0.4 part by weight of platinum catalyst;

[0139] 1.2 parts by weight of inhibitor;

[0140] 0.1 part by weight of antioxidant;

[0141] According to the above formula, the platinum catalyst and the inhibitor are mixed evenly at room temperature to obtain a catalytic system; using an open mill, the methyl vinyl silicone rubber and the hydrogen-containing silicone oil are blended evenly at room temperature to obtain a mixed rubber; the mixed rubber, the polyolefin thermoplastic elastomer, the compatibilizer and the antioxidant are

[0142] (200 °C / 160 rpm) are fully mixed evenly (to obtain a rubber-plastic premix), and then under the same conditions (200 °C / 160 rpm), the catalytic system is added to a Haake mixer, and after dynamic vulcanization at 200 °C / 160 rpm, a polyolefin thermoplastic elastomer / silicone rubber thermoplastic vulcanizate (TPV) is obtained.

[0143] The TPV is pressed into a 2-mm-thick sheet according to the standard and its properties are tested

[0144] Comparative Example 1

[0145] The raw materials selected and their weight parts are as follows:

[0146] 50 parts by weight of methyl vinyl silicone rubber (Mn = 600,000);

[0147] 50 parts by weight of polyolefin thermoplastic elastomer (Mn = 150,000);

[0148] 7 parts by weight of compatibilizer (polypropylene grafted maleic anhydride);

[0149] 3 parts by weight of compatibilizer (glycidyl acid terpolymer);

[0150] 6 parts by weight of hydrogen-containing silicone oil;

[0151] 0.4 parts by weight of platinum catalyst;

[0152] 1.2 parts by weight of inhibitor;

[0153] 0.1 parts by weight of antioxidant.

[0154] According to the above formula, the platinum catalyst and the inhibitor are mixed evenly at room temperature to obtain a catalytic system; using an open mill, the methyl vinyl silicone rubber and the hydrogen-containing silicone oil are blended evenly at room temperature to obtain a mixed rubber; the mixed rubber, the polyolefin thermoplastic elastomer, the compatibilizer and the antioxidant are

[0155] fully mixed evenly (to obtain a rubber-plastic premix) in a Haake mixer at (200 °C / 160 rpm), and then the catalytic system is added to the Haake mixer under the same conditions (200 °C / 160 rpm), and dynamically vulcanized at 200 °C / 160 rpm to obtain a polyolefin thermoplastic elastomer / silicone rubber thermoplastic vulcanizate TPV.

[0156] The TPV is pressed into a 2-mm-thick sheet according to the standard and its properties are tested. The test results are shown in Table 1.

[0157] Comparative Example 2

[0158] The raw materials selected and their parts by weight are as follows:

[0159] 50 parts by weight of methyl vinyl silicone rubber (Mn = 600,000);

[0160] 50 parts by weight of polyolefin thermoplastic elastomer (Mn = 150,000);

[0161] 10 parts by weight of compatibilizer (polyolefin thermoplastic elastomer grafted silane);

[0162] 6 parts by weight of hydrogen-containing silicone oil;

[0163] 1.2 parts by weight of inhibitor;

[0164] 0.1 parts by weight of antioxidant.

[0165] According to the above formula, an inhibitor is used as the catalytic system; using an open mill, methyl vinyl silicone rubber and hydrogen-containing silicone oil are blended evenly at room temperature to obtain a mixed rubber; the mixed rubber, polyolefin thermoplastic elastomer, compatibilizer and antioxidant are fully mixed evenly in a Haake mixer (200 °C / 160 rpm) (to obtain a rubber-plastic premix), and then under the same conditions (200 °C / 160 rpm), the catalytic system is added to the Haake mixer, and after dynamic vulcanization under the conditions of 200 °C / 160 rpm, a polyolefin thermoplastic elastomer / silicone rubber thermoplastic vulcanizate TPV is obtained.

[0166] The TPV is pressed into a 2-mm-thick sheet according to the standard and its properties are tested. The test results are shown in Table 1.

[0167] Comparative Example 3

[0168] The raw materials selected and their parts by weight are as follows:

[0169] 50 parts by weight of methyl vinyl silicone rubber (Mn = 600000);

[0170] 50 parts by weight of polyolefin thermoplastic elastomer (Mn = 150000);

[0171] 10 parts by weight of compatibilizer (polyolefin thermoplastic elastomer grafted with silane);

[0172] 6 parts by weight of hydrogen-containing silicone oil;

[0173] 0.4 parts by weight of platinum catalyst;

[0174] 0.1 parts by weight of antioxidant.

[0175] According to the above formula, a platinum catalyst is used as the catalytic system; using an open mill, methyl vinyl silicone rubber and hydrogen-containing silicone oil are blended evenly at room temperature to obtain a mixed rubber; the mixed rubber, polyolefin thermoplastic elastomer, compatibilizer and antioxidant are fully mixed evenly in a Haake mixer (200 °C / 160 rpm) (to obtain a rubber-plastic premix), and then under the same conditions (200 °C / 160 rpm), the catalytic system is added to the Haake mixer, and after dynamic vulcanization under the conditions of 200 °C / 160 rpm, a polyolefin thermoplastic elastomer / silicone rubber thermoplastic vulcanizate TPV is obtained.

[0176] The TPV is pressed into a 2-mm-thick sheet according to the standard and its properties are tested. The test results are shown in Table 1.

[0177] Table 1

[0178]

[0179] In Table 1: The tensile strength was determined in accordance with GB / T 528-2009, the elongation at break was determined in accordance with GB / T 528-2009, the hardness (Shore A) was determined in accordance with GB / T 531.1-2008, the tensile permanent set was determined in accordance with GB / T 528-2009, and the gas permeability coefficient was determined in accordance with GB-1038-2000.

[0180] Examples 1-11 and Comparative Example 1 used different compatibilizers. Among them, Examples 1-11 used compatibilizer A or compatibilizer B of the present invention, and Comparative Example 1 used a mixture of polypropylene grafted maleic anhydride and glycidyl acid terpolymer as the compatibilizer. The data in Table 1 show that, compared with Comparative Example 1, the tensile strength of Examples 1-11 increased by 23-102%, the elongation at break increased by 24-110%, and the gas permeability coefficient increased by 4-84%. It shows that, compared with the compatibilizer of Comparative Example 1, the compatibilizer of the present invention can significantly improve the tensile strength (strength), elongation at break (toughness) and gas permeability coefficient of the product. Compared with the compatibilizer of Comparative Example 1, the mechanical properties of the polyolefin thermoplastic elastomer / silicone rubber thermoplastic vulcanizate TPV prepared with the compatibilizer of the present invention are better.

[0181] Compared with Comparative Example 1, Example 1 used different compatibilizers, but the amount of the compatibilizer was the same. Among them, Example 1 used compatibilizer A of the present invention, and Comparative Example 1 used a mixture of polypropylene grafted maleic anhydride and glycidyl acid terpolymer as the compatibilizer. The data in Table 1 show that, compared with Comparative Example 1, the tensile strength of Example 1 increased by 102%, the elongation at break increased by 110%, the tensile permanent set decreased by 36%, and the gas permeability coefficient increased by 84%. It shows that, compared with the compatibilizer of Comparative Example 1, the compatibilizing effect of compatibilizer A of the present invention is better; it can significantly improve the tensile strength (strength), elongation at break (toughness) and gas permeability coefficient of the product, reduce the tensile permanent set, and improve the appearance of the product.

[0182] Compared with Comparative Example 1, Example 11 used different compatibilizers, but the amount of the compatibilizer was the same. Among them, Example 11 used compatibilizer B of the present invention, and Comparative Example 1 used a mixture of polypropylene grafted maleic anhydride and glycidyl acid terpolymer as the compatibilizer. The data in Table 1 show that, compared with Comparative Example 1, the tensile strength of Example 11 increased by 43%, the elongation at break increased by 71%, the tensile permanent set decreased by 39%, and the gas permeability coefficient increased by 64%. It shows that, compared with the compatibilizer of Comparative Example 1, the compatibilizing effect of compatibilizer B of the present invention is better; it can significantly improve the tensile strength (strength), elongation at break (toughness) and gas permeability coefficient of the product, reduce the tensile permanent set, and improve the appearance of the product.

[0183] The difference between Comparative Example 2 and Example 1 is only that the catalyst was not used in Comparative Example 2. The data in Table 1 show that, compared with Example 1, the tensile strength of Comparative Example 2 decreased by 56%, the elongation at break decreased by 59%, and the extrusion appearance was rough. It can be concluded that the catalyst plays a role in improving the tensile strength (strength) and elongation at break (toughness) of the product and improving the appearance of the product in the present invention.

[0184] The difference between Comparative Example 3 and Example 1 is only that the inhibitor was not used in Comparative Example 3. The data in Table 1 show that, compared with Example 1, the tensile strength of Comparative Example 3 decreased by 47%, the elongation at break decreased by 46%, and the extrusion appearance was rough. It can be concluded that the inhibitor plays a role in improving the tensile strength (strength) and elongation at break (toughness) of the product and improving the appearance of the product in the present invention.

[0185] In Example 5, the rotor speed was reduced from 160 rpm to 80 rpm compared with Example 1; in Example 6, the rotor speed was increased from 160 rpm to 200 rpm compared with Example 1. The data in Table 1 show that: the rotor speed can affect the properties of the prepared TPV, and there is an optimal rotor speed to prepare the TPV with the best properties.

[0186] In Example 7, the molecular weight of the polyolefin thermoplastic elastomer was reduced from 150,000 to 50,000 compared with Example 1; in Example 8, the molecular weight of the polyolefin thermoplastic elastomer was increased from 150,000 to 250,000 compared with Example 1. The data in Table 1 show that: the molecular weight of the polyolefin thermoplastic elastomer matrix can affect the properties of the prepared TPV, and there is an optimal molecular weight to prepare the TPV with the best properties.

[0187] In Example 9, the methyl vinyl silicone rubber was replaced with methyl vinyl phenyl silicone rubber compared with Example 2; in Example 10, the methyl vinyl silicone rubber was replaced with fluorosilicone rubber compared with Example 2. The data in Table 1 show that: when using methyl vinyl silicone rubber for the next preparation in Example 2, the properties of the obtained product are the best.

[0188] Other performance tests

[0189] (1) Stain resistance test

[0190] Taking the TPV prepared in Example 1 as a specimen, its stain resistance was measured according to QBT 5070-2017 and GB / T251-2008, and the surface condition of the specimen was judged according to GB / T251-2008. The test results are as Figure 2 shown. Figure 2 Among them, tomato ketchup, engine oil, freshly squeezed orange juice, instant coffee, tea, and red wine are the pollution sources. Figure 2It shows that under the measured pollution source, the color difference value of the sample is 0.15 - 0.43; according to the grey scale for assessing staining of textiles for color fastness tests, the color fastness grade of the sample is 4 - 5 levels, and the pollution resistance reaches the highest level of 5. This indicates that the sample has excellent stain resistance performance.

[0191] (II) Yellowing resistance and ultraviolet resistance

[0192] Taking the TPV prepared in Example 1 as the sample, the yellowing resistance and ultraviolet resistance are measured according to HGT 3689 - 2014 and GB / T250 - 2008, and the surface condition of the sample is measured according to GB / T250 - 2008. The test results are as Figure 3 shown. Figure 3 It shows that under the sun lamp method test, the color difference value of the tested sample is 0.12 - 0.2 within 36 h, and according to the grey scale for assessing change in color of textiles for color fastness tests, the color fastness grade of the sample is 5 levels; the color difference value of the tested sample is 0.12 - 0.33 within 72 h, and according to the grey scale for assessing change in color of textiles for color fastness tests, the color fastness grade of the sample is 4 - 5 levels; under the ultraviolet lamp tube method test, the color difference value of the tested sample is 0.09 - 0.17 within 48 h, and according to the grey scale for assessing change in color of textiles for color fastness tests, the color fastness grade of the sample is 5 levels; the color difference value of the tested sample is 0.09 - 0.31 within 72 h, and according to the grey scale for assessing change in color of textiles for color fastness tests, the color fastness grade of the sample is 4 - 5 levels. This indicates that the sample has excellent yellowing resistance and ultraviolet resistance.

[0193] (III) Perspiration resistance test

[0194] The TPV prepared in Example 1 is pressed into a thin sheet with a thickness of 2 mm and cut into a size of 2 cm × 2 cm as the sample. The samples are respectively soaked in artificial perspiration with pH values of 5.5 and 8.0, taken out and wrapped with gauze moistened with the same artificial perspiration and then put into a sealed bag. The surface changes of the samples are observed at 3×24 h and 7×24 h respectively. When the samples are not soaked in perspiration, the surface is complete and smooth; after the samples are tested for perspiration at 3×24 h and 7×24 h, there are no obvious changes on the surface. For example, there is no surface peeling, damage or yellowing and rotting phenomenon. This shows that the samples have strong perspiration resistance and are not easily damaged or deteriorated.

Claims

1. A polyolefin thermoplastic elastomer / silicone rubber thermoplastic vulcanizate, characterized in that: The polyolefin thermoplastic elastomer / silicone rubber thermoplastic vulcanizate is prepared by dynamic vulcanization from raw materials including the following components; The components and their parts by weight are as follows: The total of silicone rubber and polyolefin thermoplastic elastomer is 100 parts by weight; The compatibilizer is 1-40 parts by weight, preferably 5-20 parts by weight; The vulcanizing agent is 1-15 parts by weight, preferably 3-10 parts by weight; The platinum catalyst is 0.1-3 parts by weight, preferably 0.1-1 part by weight; The inhibitor is 0.1-6 parts by weight, preferably 0.3-2 parts by weight; The antioxidant is 0.01-0.8 parts by weight, preferably 0.02-0.5 parts by weight; The weight ratio of the silicone rubber to the polyolefin thermoplastic elastomer is (30-90):(70-10), preferably (50-80):(50-20); The compatibilizer is compatibilizer A or compatibilizer B; The compatibilizer A is a polyolefin thermoplastic elastomer grafted with silane; The compatibilizer B is composed of a polyolefin thermoplastic elastomer grafted with maleic anhydride and a glycidyl acid terpolymer in a weight ratio of (3-4.5):(2-0.5); preferably, the weight ratio of the polyolefin thermoplastic elastomer grafted with maleic anhydride to the glycidyl acid terpolymer is (3.5-4):(1.5-1).

2. The polyolefin thermoplastic elastomer / silicone rubber thermoplastic vulcanizate according to claim 1, characterized in that: The silicone rubber is selected from high-temperature vulcanized silicone rubber, preferably at least one of methyl vinyl silicone rubber, methyl vinyl phenyl silicone rubber and fluorosilicone rubber.

3. The polyolefin thermoplastic elastomer / silicone rubber thermoplastic vulcanizate according to claim 1, characterized in that: The number-average molecular weight of the silicone rubber is 5000-800000, preferably 550000-700000.

4. The polyolefin thermoplastic elastomer / silicone rubber thermoplastic vulcanizate according to claim 1, characterized in that: The number-average molecular weight of the polyolefin thermoplastic elastomer is 5000-500000, preferably 15000-200000.

5. The polyolefin thermoplastic elastomer / silicone rubber thermoplastic vulcanizate according to claim 1, wherein: The vulcanizing agent is hydrogen-containing silicone oil; the content of active hydrogen in the hydrogen-containing silicone oil is 0.5-1.5 wt%, preferably 0.6-0.8 wt%.

6. The polyolefin thermoplastic elastomer / silicone rubber thermoplastic vulcanizate according to claim 1, characterized in that: The platinum catalyst is selected from liquid platinum catalysts, preferably at least one of isopropyl alcohol complexes of chloroplatinic acid, platinum catalysts coordinated with tetrahydrofuran, and platinum catalysts coordinated with methyl vinyl siloxane.

7. The polyolefin thermoplastic elastomer / silicone rubber thermoplastic vulcanizate according to claim 1, wherein: The inhibitor is selected from at least one of alkynol inhibitors, azo inhibitors and heavy metal ion compounds, preferably alkynol inhibitors.

8. The polyolefin thermoplastic elastomer / silicone rubber thermoplastic vulcanizate according to claim 1, wherein: The antioxidant is selected from at least one of hindered phenol antioxidants, phosphite antioxidants and thio propionate antioxidants, preferably hindered phenol antioxidants.

9. A method for preparing a polyolefin thermoplastic elastomer / silicone rubber thermoplastic vulcanizate according to any one of claims 1-8, characterized in that, The preparation method includes the following steps: (1) Blend the silicone rubber and the vulcanizing agent evenly at room temperature to obtain a mixed rubber; mix the platinum catalyst and the inhibitor evenly at room temperature to obtain a catalytic system; (2) Rubber-plastic premixing: Mix the mixed rubber, polyolefin thermoplastic elastomer, compatibilizer and antioxidant evenly according to the weight ratio or parts by weight to obtain a rubber-plastic premix; (3) Dynamic vulcanization: adding the catalytic system to the rubber-plastic premix and carrying out dynamic vulcanization to obtain the thermoplastic vulcanizate of silicone rubber polyolefin thermoplastic elastomer; Both the rubber-plastic premixing and the dynamic vulcanization are carried out under the temperature condition of 130°C - 250°C; preferably, the dynamic vulcanization is carried out under the temperature condition of 190°C - 220°C.

10. Application of the polyolefin thermoplastic elastomer / silicone rubber thermoplastic vulcanizate according to any one of claims 1 - 8 in the field of wearable skin-friendly devices or biomedical materials.

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