Bio-based thermoplastic elastomer as well as preparation method and application thereof

Abstract

The invention discloses a bio-based thermoplastic elastomer as well as a preparation method and application thereof. The bio-based thermoplastic elastomer comprises the following raw materials in parts by weight: 100 parts of bio-based rubber, 80-200 parts of bio-based polyolefin resin, 70-130 parts of a biomass plasticizer, 10-50 parts of an auxiliary agent and 1-10 parts of a composite cross-linking agent, the biomass plasticizer comprises one or more of soybean oil, coconut oil, linseed oil and palm oil; the composite cross-linking agent is prepared from one or more of tert-butyl peroxyisopropyl carbonate, sulfur, phenolic resin, bismaleimide, diphenylsilanediol, triallyl cyanurate and 2, 5-dimethyl-2, 5-bis (tert-butylperoxy) hexane, and the composite cross-linking agent is prepared from one or more of diphenylsilanediol, diphenylsilanediol, triallyl cyanurate and 2, 5-dimethyl-2, 5-bis (tert-butylperoxy) hexane; the bio-based thermoplastic elastomer has excellent high and low temperature performance and sealing performance, and also has the advantages of aging resistance, weather resistance, high mechanical strength and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of thermoplastic elastomer materials, and in particular to a bio-based thermoplastic elastomer, a preparation method and application thereof. Background Art

[0002] As an important part of the industrial system, the automobile industry relies on the development of the industry as a whole. Its unique performance requirements and large volume have put forward demands on the development of the industry and have also contributed to the development of the industry. As an increasingly mature low-energy, continuous and recyclable material, TPV materials have obvious advantages over traditional rubber, but they still rely on petrochemical resources. Under the dual-carbon strategy and the trend of sustainable development, the future development of TPV materials is also moving towards bio-based.

[0003] At present, many universities and enterprises have launched development plans for bio-based materials and bio-based rubbers. For example, Michelin has been deeply involved in the development of bio-based butadiene and has established a bio-based butadiene plant. Japan's Sumitomo, Ajinomoto, and Germany's Bridgestone have developed bio-based isoprene. Companies such as Genencor, Lanxess, and Goodyear have also developed bio-based isoprene rubber, bio-based EPDM rubber, bio-based EPDM rubber, bio-based butyl rubber, and bio-based butadiene rubber, laying a certain foundation for the further development of bio-based thermoplastic elastomers. At present, major universities have also made a lot of research on polylactic acid-based biomass TPVs, but so far, the industrialized bio-based thermoplastic elastomers that meet both performance requirements and production capacity requirements still limit the further development and application of bio-based thermoplastic elastomers. Summary of the invention

[0004] In view of the deficiencies in the prior art, the present invention provides a bio-based thermoplastic elastomer, a preparation method and applications thereof.

[0005] A bio-based thermoplastic elastomer comprises the following raw materials in parts by weight: 100 parts of bio-based rubber, 80-200 parts of bio-based polyolefin resin, 70-130 parts of biomass plasticizer, 10-50 parts of auxiliary agent and 1-10 parts of composite cross-linking agent; the biomass plasticizer comprises one or more of soybean oil, coconut oil, linseed oil and palm oil; the composite cross-linking agent comprises one or more of tert-butyl peroxyisopropyl carbonate, sulfur, phenolic resin, bismaleimide, diphenylsilanediol, triallyl cyanurate and 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane.

[0006] Preferably, the invention further comprises 100-150 parts by weight of a biomass filler; the biomass filler comprises one or more of starch, lignin, cellulose, diatomaceous earth and rice white carbon black.

[0007] Preferably, the invention further comprises 10-50 parts by weight of an auxiliary agent, wherein the auxiliary agent comprises one or more of an antioxidant, a light stabilizer, a lubricant and an antistatic agent.

[0008] Preferably, the antioxidant includes one or more of hindered phenols and phosphites; the light stabilizer includes one or more of hindered amines, UV absorbers, shielding agents and quenchers; and the lubricant includes silicone masterbatch.

[0009] Preferably, the bio-based rubber includes one or more of bio-based nitrile rubber, bio-based itaconate rubber, hydrogenated bio-based itaconate rubber, bio-based isoprene rubber, bio-based EPDM rubber, bio-based butadiene rubber and bio-based butyl rubber.

[0010] Preferably, the bio-based polyolefin resin includes one or more of bio-based PP and bio-based PE.

[0011] A method for preparing a bio-based thermoplastic elastomer comprises the following steps:

[0012] 100 parts of bio-based rubber are crushed, and 70-130 parts of biomass plasticizer, 80-200 parts of bio-based polyolefin resin, 100-150 parts of biomass filler and 10-50 parts of auxiliary agent are added, stirred and mixed to obtain a premix A;

[0013] 1-10 parts of a composite cross-linking agent are added to the premix A, and the premix is ​​melted, extruded, granulated, and dried to remove odor to obtain a bio-based thermoplastic elastomer.

[0014] Preferably, the stirring temperature is 150-250°C.

[0015] Preferably, the stirring time is 5-10 min.

[0016] The above-mentioned bio-based thermoplastic elastomer or the bio-based thermoplastic elastomer prepared by the above-mentioned preparation method is used in the production of automotive seals, new energy vehicle cooling systems, fuel vehicle engines, steering dust covers and tires.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] 1. The present invention mainly uses bio-based materials such as bio-based rubber Bio-NBR and BIR. Reasonable material selection can not only realize continuous and mass production, but also effectively improve the medium resistance and heat resistance of the material. The final product has excellent high and low temperature performance and sealing, as well as the advantages of anti-aging, weather resistance and high mechanical strength.

[0019] 2. The present invention uses bio-based rubber as the main material, and the plasticizer is added in batches, which can effectively ensure the plasticizing effect of each component, avoid uneven plasticization, and reduce the viscosity of the system. It can reduce the difficulty of processing technology to a certain extent, improve production stability, adapt to a wider range of screws and processes, and at the same time increase production capacity and reduce energy consumption.

[0020] 3. The present invention has a reasonable ratio and excellent processing technology. In the optimized process, the two-step extrusion method can complete the production of the final product, and obtain a continuously produced dynamic vulcanized rubber / resin mixture. In addition, the product obtained by the two-step method has a reduced gel content and a reduced risk of precipitation. It can be produced continuously and is suitable for various molding processes such as injection molding, extrusion, and blow molding.

[0021] 4. The present invention optimizes the production steps through reasonable production process design, and only needs two steps of extrusion to complete the production of bio-based thermoplastic elastomers. The production process is simple, stable, easy to control, environmentally friendly, and has low equipment requirements, which is beneficial to large-scale industrial production. DETAILED DESCRIPTION

[0022] The technical solutions in the embodiments of the present invention are described clearly and completely. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] Example 1

[0024] This embodiment provides a bio-based thermoplastic elastomer, which includes the following raw materials in parts by weight: 100 parts of bio-based rubber, 80 parts of bio-based polyolefin resin, 130 parts of biomass plasticizer, 150 parts of biomass filler, 1 part of composite cross-linking agent, and 30 parts of auxiliary agent; wherein:

[0025] The bio-based rubber is ternary hydrogenated bio-based itaconate rubber with a Mooney viscosity of 40MU and a third monomer content of 2.0%. The bio-based polyolefin resin is biomass PP, the plasticizer is coconut oil, the filler is rice silica, the composite cross-linking agent is 50% 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane and 50% triallyl cyanurate, and the additives are 10% antioxidant and 40% light stabilizer, 40% lubricant and 10% antistatic agent.

[0026] The method for preparing the bio-based thermoplastic elastomer of this embodiment comprises the following steps:

[0027] S1. The crushed bio-based rubber, bio-based polyolefin resin and biomass filler were mixed at 230°C and a rotor speed of 40 r / min for 20 minutes, and then the additive was added and mixed for 5 minutes to obtain a premix A;

[0028] S2. The premix A and the composite vulcanizing agent are respectively and continuously quantitatively added to the first section of the solid conveying zone of the extruder, and the biomass plasticizer is respectively and continuously and quantitatively added to the front section and the middle section, and the vacuum pump is used to vacuumize the tail section of the extruder, melt, extrude, granulate, dry and deodorize to obtain a bio-based thermoplastic elastomer;

[0029] The extruder in the above step S2 is a co-rotating twin-screw extruder, with a feed speed of 200 r / min, a screw speed of 400 r / min, a screw aspect ratio of 68, a first section temperature of the solid conveying zone not exceeding 120° C., and a temperature of the remaining sections of 230° C.;

[0030] Example 2

[0031] This embodiment provides a bio-based thermoplastic elastomer, which includes the following raw materials in parts by weight: 100 parts of bio-based rubber, 200 parts of bio-based polyolefin resin, 100 parts of biomass plasticizer, 150 parts of biomass filler, 10 parts of composite cross-linking agent, and 10 parts of auxiliary agent; wherein:

[0032] The bio-based rubber is ternary hydrogenated bio-based itaconate rubber with a Mooney viscosity of 40, a third monomer content of 2.2%, a plasticizer of coconut oil, and a filler of diatomaceous earth; the composite cross-linking agent is a mixture of 50% phenolic resin and 50% bismaleimide, and the additives are 20% antioxidants, 40% light stabilizers, 30% lubricants, and 10% antistatic agents.

[0033] The method for preparing the bio-based thermoplastic elastomer of this embodiment comprises the following steps:

[0034] S1. The crushed bio-based rubber, bio-based polyolefin resin and biomass filler were mixed at 220°C and a rotor speed of 50 r / min for 10 minutes and then the additive was added and mixed for 5 minutes to obtain a premix A;

[0035] S2. The premix A and the composite vulcanizing agent are respectively and continuously quantitatively added to the first section of the solid conveying zone of the extruder, and the biomass plasticizer is respectively and continuously and quantitatively added to the front section and the middle section, and the vacuum pump is used to vacuumize the tail section of the extruder, melt, extrude, granulate, dry and deodorize to obtain a bio-based thermoplastic elastomer;

[0036] The extruder in the above step S2 is a co-rotating twin-screw extruder, the feed speed is 220r / min, the screw speed is 350r / min, the screw aspect ratio is 64, the temperature of the first section of the solid conveying zone does not exceed 120°C, and the temperature of the remaining sections is 220°C;

[0037] Example 3

[0038] This embodiment provides a bio-based thermoplastic elastomer, which includes the following raw materials in parts by weight: 100 parts of bio-based rubber, 120 parts of bio-based polyolefin resin, 70 parts of biomass plasticizer, 100 parts of biomass filler, 5 parts of composite cross-linking agent, and 50 parts of auxiliary agent; wherein:

[0039] The bio-based rubber is ternary hydrogenated bio-based itaconate rubber with a Mooney viscosity of 60, a third monomer content of 2.2%, coconut oil as the plasticizer, and cellulose as the filler; the composite cross-linking agent is a mixture of 30% isopropyl peroxy tert-butyl carbonate and 70% bismaleimide, and the additives are 20% antioxidants, 40% light stabilizers, 30% lubricants, and 10% antistatic agents.

[0040] The method for preparing the bio-based thermoplastic elastomer of this embodiment comprises the following steps:

[0041] S1. The crushed bio-based rubber, bio-based polyolefin resin and biomass filler were mixed at 220°C and a rotor speed of 40 r / min for 20 minutes and then the additive was added and mixed for 10 minutes to obtain a premix A;

[0042] S2. The premix A and the composite vulcanizing agent are respectively and continuously quantitatively added to the first section of the solid conveying zone of the extruder, and the biomass plasticizer is respectively and continuously and quantitatively added to the front section and the middle section, and the vacuum pump is used to vacuumize the tail section of the extruder, melt, extrude, granulate, dry and deodorize to obtain a bio-based thermoplastic elastomer;

[0043] The extruder in the above step S2 is a co-rotating twin-screw extruder, the feed speed is 180r / min, the screw speed is 400r / min, the screw aspect ratio is 64, the temperature of the first section of the solid conveying zone does not exceed 120°C, and the temperature of the remaining sections is 210°C;

[0044] Comparative Example 1

[0045] This comparative example proposes a thermoplastic elastomer. The raw materials and amounts used in this comparative example are the same as those in Example 3. The only difference from Example 3 is the preparation steps. The preparation method of the thermoplastic elastomer in this comparative example includes the following steps:

[0046] S1. The crushed bio-based rubber, bio-based polyolefin resin and biomass filler were mixed at 220°C and a rotor speed of 40 r / min for 20 minutes and then the additive was added and mixed for 10 minutes to obtain a premix A;

[0047] S2. The premix A is added in a continuous and quantitative manner to the first section of the solid conveying zone of the extruder, a biomass plasticizer is added in a continuous and quantitative manner in the front section, a vacuum pump is used to evacuate the extruder at the rear section, and the intermediate B is obtained by melting, extruding, and granulating;

[0048] S3. The intermediate B and the composite vulcanizing agent are respectively and continuously quantitatively added to the first section of the solid conveying zone of the extruder, the biomass plasticizer is continuously and quantitatively added in the front section, and the vacuum pump is used to vacuumize the tail section of the extruder, melt, extrude, granulate, dry and deodorize to obtain a bio-based thermoplastic elastomer;

[0049] The extruder in the above steps S2 and S3 is a co-rotating twin-screw extruder, with a feed speed of 180 r / min, a screw speed of 400 r / min, a screw aspect ratio of 64, a first section temperature of the solid conveying zone not exceeding 120° C., and a temperature of the remaining sections of 190° C.;

[0050] Comparative Example 2

[0051] This comparative example proposes a thermoplastic elastomer. The preparation method of the thermoplastic elastomer in this comparative example is the same as the preparation method of Example 3. The only difference from Example 3 is the raw materials and the dosage. The thermoplastic elastomer in this comparative example includes the following raw materials in parts by weight: 100 parts of bio-based rubber, 130 parts of bio-based polyolefin resin, 100 parts of biomass plasticizer, 120 parts of biomass filler, 5 parts of composite cross-linking agent, and 20 parts of auxiliary agent; wherein:

[0052] The bio-based rubber is bio-based EPDM rubber with a Mooney viscosity of 38 and a third monomer content of 1.8%. The plasticizer is coconut oil and the filler is cellulose. The composite cross-linking agent is a mixture of 30% isopropyl peroxy tert-butyl carbonate and 70% bismaleimide. The additives are 20% antioxidants, 40% light stabilizers, 30% lubricants and 10% antistatic agents.

[0053] Test Case

[0054] The thermoplastic elastomers prepared in Examples 1-3 and Comparative Examples 1-2 were subjected to performance tests. The test results are shown in Table 1. The test methods are as follows:

[0055] Hardness, measured according to ISO 7619-1, Type A;

[0056] Tensile strength: the test standard is ISO 37-1, using type I dumbbell specimens, and the tensile test rate is 500 mm / min;

[0057] Elongation at break: the test standard is ISO 37-1, using type I dumbbell specimens, and the tensile test rate is 500 mm / min;

[0058] Tear strength, test standard is ISO 34-1, method B, use uncut rectangular specimen, test rate is 500mm / min;

[0059] Heat resistance, test standard is GB / T 3512, 125℃*1000h;

[0060] Chemical resistance, tested according to ISO 1817, including gasoline, diesel, antifreeze, brake fluid, engine oil, transmission oil, etc.

[0061] Weather resistance, tested according to SAE J2527;

[0062] Low temperature brittleness, according to ASTM D746-2020, there is no crack in the freezing time of 5 minutes, and the temperature meets ≤-60℃;

[0063] Compression set, tested according to ISO 815, Type A, 125℃*72h;

[0064] Table 1 Performance test results of thermoplastic elastomers prepared in Examples 1-3 and Comparative Examples 1-2

[0065]

[0066]

[0067] It can be seen from the results in Table 1 that the materials prepared in Examples 1-3h and Comparative Example 1 of the present invention have more excellent medium resistance. At the same time, the heat resistance and compression permanent deformation of Examples 1-3 and Comparative Example 1 are generally better than those of Comparative Example 2. Compared with Comparative Example 2, Examples 1-3 and Comparative Example 1 have higher mechanical strength and better weather resistance.

[0068] In Example 1, the plasticizer content is relatively high, and the composite crosslinking agent is 1 part; compared with Example 1, in Example 2, there is a lower plasticizer content and a higher amount of composite crosslinking agent. Compared with Example 1, Example 2 has a higher hardness, and the mechanical properties and weather resistance are more excellent. At the same time, Example 3 has a lower plasticizer content. Compared with Examples 1 and 3, Example 2 has a medium hardness, and the mechanical properties and weather resistance are more excellent, and the compression permanent deformation is also relatively excellent;

[0069] Compared with Example 3, Comparative Example 1 uses the same material formula, but the processing is carried out according to the traditional method. It can be seen from the comparison that although the traditional multi-step method is conducive to improving dispersion and increasing the degree of cross-linking, it has no obvious advantages in various aspects such as mechanical properties. It is obvious that the cost will be increased;

[0070] Compared with Example 3, the dosage of the formula in Comparative Example 2 is the same as that in Example 3, but the rubber used is different, and the mechanical properties, medium resistance, compression permanent deformation, and heat resistance of Comparative Example 2 are not as good as those of Examples 1-3 and Comparative Example 1. Therefore, reasonable and efficient formula design and process route have a significant impact on process stability and final product performance.

[0071] In the description of this specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0072] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, and these changes and improvements all fall within the scope of the present invention to be protected.

Claims

1. A bio-based thermoplastic elastomer, characterized in that: The invention comprises the following raw materials in parts by weight: 100 parts of bio-based rubber, 80-200 parts of bio-based polyolefin resin, 70-130 parts of biomass plasticizer and 1-10 parts of composite cross-linking agent; the biomass plasticizer comprises one or more of soybean oil, coconut oil, linseed oil and palm oil; the composite cross-linking agent comprises one or more of isopropyl peroxy tert-butyl carbonate, sulfur, phenolic resin, bismaleimide, diphenylsilanediol, triallyl cyanurate and 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane.

2. The bio-based thermoplastic elastomer according to claim 1, characterized in that The invention also comprises 100-150 parts by weight of a biomass filler; the biomass filler comprises one or more of starch, lignin, cellulose, diatomaceous earth and rice white carbon black.

3. The bio-based thermoplastic elastomer according to claim 1, characterized in that The invention also comprises 10-50 parts by weight of auxiliary agents, wherein the auxiliary agents include one or more of an antioxidant, a light stabilizer, a lubricant and an antistatic agent.

4. The bio-based thermoplastic elastomer according to claim 3, characterized in that The antioxidant includes one or more of hindered phenols and phosphites; the light stabilizer includes one or more of hindered amines, ultraviolet absorbers, shielding agents and quenchers; and the lubricant includes silicone masterbatch.

5. The bio-based thermoplastic elastomer according to claim 1, characterized in that The bio-based rubber includes one or more of bio-based nitrile rubber, bio-based itaconate rubber, hydrogenated bio-based itaconate rubber, bio-based isoprene rubber, bio-based EPDM rubber, bio-based butadiene rubber and bio-based butyl rubber.

6. The bio-based thermoplastic elastomer according to claim 1, characterized in that The bio-based polyolefin resin includes one or more of bio-based PP and bio-based PE.

7. A method for preparing a bio-based thermoplastic elastomer, characterized in that: The following steps are involved: 100 parts of bio-based rubber are crushed, and 70-130 parts of biomass plasticizer, 80-200 parts of bio-based polyolefin resin, 100-150 parts of biomass filler and 10-50 parts of auxiliary agent are added, stirred and mixed to obtain a premix A; 1-10 parts of a composite cross-linking agent are added to the premix A, and the premix is ​​melted, extruded, granulated, and dried to remove odor to obtain a bio-based thermoplastic elastomer.

8. The method for preparing a bio-based thermoplastic elastomer according to claim 6, characterized in that: The stirring temperature is 220-230°C.

9. The method for preparing a bio-based thermoplastic elastomer according to claim 6, characterized in that: The stirring time is 10-20 min.

10. Use of the bio-based thermoplastic elastomer according to any one of claims 1 to 6 or the bio-based thermoplastic elastomer prepared by the preparation method according to any one of claims 7 to 9 in the production of automotive seals, new energy vehicle cooling systems, fuel vehicle engines, steering dust covers and tires.

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