High-weather-resistance photodiffusion thermoplastic elastomer as well as preparation method and application thereof

Abstract

The invention discloses a high-weather-resistance photodiffusion thermoplastic elastomer and a preparation method and application thereof, and the high-weather-resistance photodiffusion thermoplastic elastomer is prepared from the following components in parts by weight: 100 parts of styrene thermoplastic elastomer, 80-300 parts of plasticizer, 30-150 parts of polyolefin resin, 30-150 parts of styrene-acrylonitrile copolymer, 10-70 parts of compatilizer, 1-20 parts of hydroxylation reactant and 1-20 parts of other auxiliaries, and 5-50 parts of a transparent filler. The thermoplastic elastomer, the polyolefin, the styrene-acrylonitrile copolymer and the like are used as main materials, the transparent filler and the compatilizer are preferably selected, the thermoplastic elastomer material with different refractive indexes and excellent compatibility is obtained through reasonable formula design, and compared with a traditional PC / ABS encapsulation material, the formula does not contain a TPU material commonly used for encapsulation and injection adhesion, and the thermoplastic elastomer material has the advantages of being low in cost, low in cost and the like. Meanwhile, a grafting material is not added to serve as a compatilizer, so that the material has more excellent weather resistance, heat resistance and shear resistance and is easy to form.

Description

Technical Field

[0001] The invention relates to the field of thermoplastic elastomers, in particular to a highly weather-resistant light-diffusing thermoplastic elastomer and a preparation method and application thereof. Background Art

[0002] New energy vehicles use electricity as the main or auxiliary energy source, which leads to the cancellation or weakening of the gearbox, and also makes room for the wireless charging panel corresponding to the wireless charging function of handheld devices. The main material of the wireless charging panel is PC / ABS coated by thermoplastic elastomer through the coating injection bonding process.

[0003] However, the existing thermoplastic elastomers for encapsulation have problems such as poor weather resistance, hydrolysis resistance, poor appearance, thick adhesive layer, loose coating, high total weight of parts and strong odor. In addition, the common grafting modification of SEBS is generally GMA, MAH, etc., among which MAH grafting modification is the most widely used, but it is difficult to increase the grafting rate, which is generally only 0.5-2%. Correspondingly, by-products and small molecules have an adverse effect on the use of the product.

[0004] On the other hand, the atmosphere of technological car interiors is not only created by hardware facilities, but its lighting effects can also highlight the sense of technology. Different from traditional soft leather coverings, the current atmosphere lighting mainly relies on light strips, which further puts forward further requirements for the softening of light diffusion. Summary of the invention

[0005] In view of this, the present invention provides a highly weather-resistant light-diffusing thermoplastic elastomer and a preparation method and application thereof, and proposes a thermoplastic elastomer for coating that can achieve thinner, lighter, scratch-resistant, firm coating, excellent appearance, weather resistance, and light diffusion.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] In a first aspect, the present invention discloses a highly weather-resistant light-diffusing thermoplastic elastomer, which is prepared from the following components in parts by weight:

[0008]

[0009]

[0010] As a further solution of the present invention: the styrene-based thermoplastic elastomer is at least one of hydroxylated styrene-ethylene / butylene-styrene block copolymers, styrene-ethylene-propylene-styrene block copolymers, and styrene-polyisoprene-polystyrene block copolymers.

[0011] As a further solution of the present invention: the plasticizer is at least one of paraffin oil, cycloalkane oil, aromatic hydrocarbon oil and straight-chain alkane oil having a flash point greater than 200°C and a kinematic viscosity greater than 100 mm2 / s at 40°C.

[0012] As a further solution of the present invention: the polyolefin resin is one or more of homopolypropylene, copolymer polypropylene, metallocene polypropylene, ethylene-octene copolymer, polyethylene, with a light transmittance of 40% to 90% and a refractive index of 1.40 to 1.50.

[0013] As a further solution of the present invention: the refractive index of the styrene-acrylonitrile copolymer is 1.57, and the melt index is 1-5 g / 10 min.

[0014] As a further embodiment of the present invention: the compatibilizer is at least one of maleic anhydride grafted styrene copolymer, maleic anhydride grafted polyether polyurethane, glycidyl methacrylate grafted styrene copolymer, glycidyl methacrylate grafted olefin copolymer, and polycarbonate; and / or,

[0015] The other auxiliary agent is at least one of a lubricant, an antioxidant, and a light stabilizer; and / or,

[0016] The lubricant is at least one of silicone masterbatch and erucic acid amide; and / or,

[0017] The antioxidant is at least one of a hindered phenol antioxidant and a phosphite antioxidant; and / or,

[0018] The light stabilizer is at least one of an inorganic shielding agent, a benzotriazole light stabilizer, a triazine light stabilizer, and a hindered amine derivative.

[0019] As a further solution of the present invention: the filler is at least one of calcium carbonate, talcum powder, glass fiber, quartz sand, and glass microbeads, and the mesh size is 600-8000 mesh.

[0020] As a further solution of the present invention: the hydroxylation reactant is gaseous carbon dioxide, and its purity is above 97%.

[0021] On the other hand, the present invention discloses a method for preparing the above-mentioned highly weather-resistant light-diffusion thermoplastic elastomer, comprising the following steps:

[0022] S1, after premixing the styrene-based thermoplastic elastomer and the plasticizer, add the polyolefin resin, the styrene-acrylonitrile copolymer, the polycarbonate, the filler, the compatibilizer, and other additives and continue to stir and mix to obtain a mixture A;

[0023] S2, continuously and quantitatively feeding the mixture A into the first section of the solid conveying zone of the extruder, and continuously introducing the hydroxylation reactant into the front section of the extruder, and performing melting, extrusion, granulation, drying and deodorization to obtain a thermoplastic elastomer with high weather resistance and light diffusion;

[0024] The mass flow ratio of the mixture A fed into the extruder to the hydroxylation reactant is 100:(1-10).

[0025] In a third aspect, the present invention also discloses the use of the highly weather-resistant light-diffusing thermoplastic elastomer as described above in the bonding and lagging of automobile interior decoration.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] 1. The present invention uses thermoplastic elastomers, polyolefins, styrene-acrylonitrile copolymers, etc. as main materials, and selects transparent fillers and compatibilizers. Through reasonable formula design, thermoplastic elastomer materials with different refractive indices and excellent compatibility are obtained. Different from traditional PC / ABS encapsulation materials, the formula does not contain TPU materials commonly used in encapsulation injection bonding, has better weather resistance, heat resistance, and shear resistance, is easy to form, and does not need to add grafting materials as compatibilizers. In addition, in the optimized process, the one-step extrusion method can complete the production of the final product, and the obtained product has low odor and low VOC properties, while maintaining the characteristics of temperature resistance, aging resistance, weather resistance, and high mechanical strength.

[0028] 2. The present invention optimizes the production steps through reasonable production process design, and only requires a one-step extrusion method to complete the production of the highly weather-resistant light-diffusion wireless charging panel outer layer elastomer. The production process is simple, stable, easy to control, environmentally friendly, and has low equipment requirements, which is beneficial to large-scale industrial production.

[0029] 3. The highly weather-resistant light-diffusion wireless charging panel outer layer elastomer designed by the present invention can be used for overmolding including but not limited to PC, ABS, SAN, PMMA, PET, PBT, etc. DETAILED DESCRIPTION

[0030] For ease of understanding of the present invention, the present invention will be described more fully below in conjunction with specific embodiments. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thoroughly understood.

[0031] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0032] In addition, "parts" described in the Examples and Comparative Examples refer to parts by weight unless otherwise specified.

[0033] Any range described in the present invention includes the end value and any numerical value between the end values ​​and any sub-range formed by the end value or any numerical value between the end values.

[0034] Example 1

[0035] (1) Weigh the following raw materials according to weight: 100 parts of styrene thermoplastic elastomer, 300 parts of plasticizer, 30 parts of polyolefin resin, 150 parts of styrene-acrylonitrile copolymer, 5 parts of filler, 50 parts of compatibilizer, 15 parts of other additives, and 40 parts of carbon dioxide. Among them, the styrene thermoplastic elastomer is a styrene-polyisoprene-polystyrene block copolymer with a molecular weight of 160,000, the plasticizer is cycloalkane oil, the polyolefin resin is a metallocene polypropylene with a transparency of 90% and a refractive index of 1.50, the filler is a 6000 mesh transparent talc powder, the compatibilizer is a polycarbonate, and the other additives are formed by compounding phosphites, benzotriazoles, and silicone masterbatches in a mass ratio of 2:4:4.

[0036] (2) After premixing the styrene-based thermoplastic elastomer and the plasticizer at 500 r / min for 5 min, the polyolefin, styrene-acrylonitrile copolymer, filler, compatibilizer, and other additives were added, and the mixture was stirred at 100 r / min for 15 min to obtain a premix A;

[0037] (3) Premix A is continuously and quantitatively added to the first section of the solid conveying zone of the extruder, and CO2 is continuously introduced into the third section at a rate of 0.14 L / min. After melting, extrusion, granulation, drying and deodorization, a highly weather-resistant light-diffusing thermoplastic elastomer is obtained.

[0038] The extruder is a co-rotating twin-screw extruder, the feeding speed of premix A is 150 kg / h, the screw speed is 500 r / min, the screw aspect ratio is 64, the temperature of the first section of the solid conveying zone is 110° C., and the temperature of the remaining sections is 230° C.;

[0039] Example 2

[0040] (1) Weigh the following raw materials according to weight: 100 parts of styrene thermoplastic elastomer, 80 parts of plasticizer, 150 parts of polyolefin resin, 30 parts of styrene-acrylonitrile copolymer, 50 parts of filler, 10 parts of compatibilizer, 1 part of other additives, and 40 parts of carbon dioxide. Among them, the styrene thermoplastic elastomer is styrene-polyisoprene-polystyrene block copolymer with a molecular weight of 80,000, the plasticizer is paraffin oil, the polyolefin resin is homopolypropylene with a transparency of 40% and a refractive index of 1.49, the filler is 8000 mesh transparent talc powder, the compatibilizer is a compound of methacrylate glycidyl grafted olefin copolymer and polycarbonate in a mass ratio of 1:1, and the other additive is erucamide.

[0041] (2) premixing the styrene-based thermoplastic elastomer and the plasticizer at 100 r / min for 10 min, and then adding the polyolefin, styrene-acrylonitrile copolymer, filler, compatibilizer, and other additives and continuing to stir and mix at 500 r / min for 10 min to obtain a premix A;

[0042] (3) Premix A is continuously and quantitatively added to the first section of the solid conveying zone of the extruder, and CO2 is continuously introduced at 0.44 L / min in the third section to obtain a highly weather-resistant light-diffusing thermoplastic elastomer through melting, extrusion, granulation, drying and deodorization.

[0043] The extruder is a co-rotating twin-screw extruder, with a feed speed of 300 kg / h, a screw speed of 500 r / min, a screw aspect ratio of 56, a first section temperature of the solid conveying zone of 120°C, and a temperature of the remaining sections of 260°C;

[0044] Example 3

[0045] (1) Weigh the following raw materials in parts by weight for use: 100 parts of styrene thermoplastic elastomer, 250 parts of plasticizer, 50 parts of polyolefin resin, 50 parts of styrene-acrylonitrile copolymer, 30 parts of filler, 70 parts of compatibilizer, 20 parts of other additives, and 40 parts of carbon dioxide, wherein the styrene thermoplastic elastomer is a styrene-ethylene / butylene-styrene block copolymer with a molecular weight of 160,000, the plasticizer is aromatic hydrocarbon oil, the polyolefin resin is a copolymer polypropylene with a transparency of 70% and a refractive index of 1.50, the filler is 1000 mesh glass microbeads, the compatibilizer is a compound of styrene copolymer grafted with glycidyl methacrylate and polycarbonate in a mass ratio of 6:4, and the other additives are phosphites, hindered phenols, benzotriazoles, hindered amines and erucamide in a mass ratio of 2:2:3:2:1.

[0046] (2) premixing the styrene-based thermoplastic elastomer and the plasticizer at 300 r / min for 8 min, then adding the polyolefin, styrene-acrylonitrile copolymer, filler, compatibilizer, and additive, and continuing to stir and mix at 150 r / min for 12 min to obtain a premix A;

[0047] (3) Premix A is continuously and quantitatively added to the first section of the solid conveying zone of the extruder, and CO2 is continuously introduced into the third section at a rate of 0.24 L / min. After melting, extrusion, granulation, drying and deodorization, a highly weather-resistant light-diffusing thermoplastic elastomer is obtained.

[0048] The above-mentioned extruder is a co-rotating twin-screw extruder with a feed speed of 220kg / h, a screw speed of 400r / min, a screw aspect ratio of 60, a first section temperature of the solid conveying zone of 100°C, a front section to middle section temperature of 240°C, and a rear section temperature of 150°C.

[0049] Comparative Example 1

[0050] The only difference between Comparative Example 1 and Example 1 is that the compatibilizer is a maleic anhydride grafted styrene copolymer.

[0051] Comparative Example 2

[0052] The only difference between Comparative Example 2 and Example 1 is that the screw speed is 300 r / min, the temperature of the first section of the solid conveying zone is 80°C, the temperature of the front section is 200°C, the temperature of the middle section is 180°C, and the temperature of the rear section is 160°C.

[0053] Comparative Example 3

[0054] The only difference between Comparative Example 3 and Example 2 is that the filler is conventional 6000 mesh calcium carbonate.

[0055] The thermoplastic elastomers prepared in Examples 1-3 and Comparative Examples 1-3 were subjected to performance tests. The test results are shown in Table 1. The test standards / methods are as follows:

[0056] Density, test standard is ISO 1183, immersion method;

[0057] Hardness, measured according to ISO 7619-1, Type A;

[0058] Tensile strength: the test standard is ISO 37-1, using type I dumbbell specimens, and the tensile test rate is 500 mm / min;

[0059] Tear strength, test standard is ISO 34-1, method B, use uncut rectangular specimen, test rate is 500mm / min;

[0060] Weather resistance, tested according to SAE J2527, and evaluated the gray value and Lab color difference value ΔE;

[0061] Adhesion strength is tested according to TL 52622, with a requirement of ≥90N / 20mm for passing, and a test rate of 50mm / min;

[0062] Light transmittance, tested in accordance with ISO 13468, required to be ≥40%;

[0063] Haze, tested in accordance with ISO 14782, is required to be ≥ 70%.

[0064] Table 1

[0065]

[0066]

[0067] From the results in Table 1, it can be seen that Example 1 has the best bonding strength. Although the haze of Example 2 is better than that of Example 1, the light transmittance is lower, the light diffusion effect is weaker than that of Example 1, and the adhesive injection strength is significantly different from that of Example 1. The weather resistance is weaker than that of other solutions. Example 3 has the lowest hardness and can provide a softer touch, but its weather resistance is weaker than that of Example 1.

[0068] Compared with Example 1, Comparative Example 1 reduces the addition of polycarbonate, and the bonding strength of the overmolding injection bonding is slightly reduced, but the mechanical properties, light transmittance and haze all show a significant decrease. Appropriate addition of polycarbonate is beneficial to the compatibility and light diffusion effect of the final product.

[0069] Compared with Example 1, Comparative Example 2 uses the same material formula, but the process route is adjusted. It can be seen from the comparison that the shear strength and temperature of Comparative Example 2 are weaker than those of Example 1. Therefore, the bonding strength of the encapsulation injection bonding is weaker than that of Example 1. This is due to the weak reactivity of CO2. Reasonable and efficient formula design and process route have a significant impact on process stability and final product performance.

[0070] Compared with Example 2, the formulation and dosage in Comparative Example 3 are the same as Example 3, but the filler used is a conventional filler. It can be seen from the comparison that the conventional filler has a significant effect on the light transmittance, the light transmittance effect varies greatly, and the light diffusion effect is not good.

[0071] Although this specification is described according to implementation modes, not every implementation mode includes only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

[0072] Therefore, the above description is only a preferred embodiment of the present application and is not intended to limit the scope of implementation of the present application; that is, all equivalent changes made according to the scope of the claims of the present application are within the protection scope of the claims of the present application.

Claims

1. A highly weather-resistant light-diffusion thermoplastic elastomer, characterized in that: It is prepared from the following components in parts by weight:

2. The highly weather-resistant light-diffusing thermoplastic elastomer according to claim 1, characterized in that: The styrene-based thermoplastic elastomer is at least one of styrene-ethylene / butylene-styrene block copolymers, styrene-ethylene-propylene-styrene block copolymers, and styrene-polyisoprene-polystyrene block copolymers that have been subjected to hydroxylation treatment.

3. The highly weather-resistant light-diffusing thermoplastic elastomer according to claim 1, characterized in that: The plasticizer has a flash point greater than 200°C and a kinematic viscosity greater than 100 mm at 40°C. 2 / s of at least one of paraffin oil, cycloparaffin oil, aromatic oil, and straight-chain paraffin oil.

4. The highly weather-resistant light-diffusing thermoplastic elastomer according to claim 1, characterized in that: The polyolefin resin is one or more of homopolypropylene, copolymer polypropylene, metallocene polypropylene, ethylene-octene copolymer, polyethylene, with a light transmittance of 40% to 90% and a refractive index of 1.40 to 1.

50.

5. The highly weather-resistant light-diffusing thermoplastic elastomer according to claim 1, characterized in that: The refractive index of the styrene-acrylonitrile copolymer is 1.57, and the melt index is 1-5 g / 10 min.

6. The highly weather-resistant light-diffusing thermoplastic elastomer according to claim 1, characterized in that: The compatibilizer is at least one of maleic anhydride grafted styrene copolymer, maleic anhydride grafted polyether polyurethane, glycidyl methacrylate grafted styrene copolymer, glycidyl methacrylate grafted olefin copolymer, and polycarbonate; and / or, The other additives are at least one of a lubricant, an antioxidant, and a light stabilizer; and / or, The lubricant is at least one of silicone masterbatch and erucic acid amide; and / or, The antioxidant is at least one of a hindered phenol antioxidant and a phosphite antioxidant; and / or, The light stabilizer is at least one of an inorganic shielding agent, a benzotriazole light stabilizer, a triazine light stabilizer, and a hindered amine derivative.

7. The highly weather-resistant light-diffusing thermoplastic elastomer according to claim 1, characterized in that: The filler is at least one of calcium carbonate, talcum powder, glass fiber, quartz sand and glass microbeads, and has a mesh size of 600-8000 meshes.

8. The highly weather-resistant light-diffusing thermoplastic elastomer according to claim 1, characterized in that: The hydroxylation reactant is gaseous carbon dioxide, and its purity is above 97%.

9. A method for preparing the highly weather-resistant light-diffusing thermoplastic elastomer according to any one of claims 1 to 8, characterized in that: The following steps are involved: S1, after premixing the styrene-based thermoplastic elastomer and the plasticizer, add the polyolefin resin, the styrene-acrylonitrile copolymer, the polycarbonate, the filler, the compatibilizer, and other additives and continue to stir and mix to obtain a mixture A; S2, continuously and quantitatively feeding the mixture A into the first section of the solid conveying zone of the extruder, and continuously introducing the hydroxylation reactant into the front section of the extruder, and performing melting, extrusion, granulation, drying and deodorization to obtain a thermoplastic elastomer with high weather resistance and light diffusion; The mass flow ratio of the mixture A fed into the extruder to the hydroxylation reactant is 100:(1-10).

10. Use of the highly weather-resistant light-diffusing thermoplastic elastomer according to any one of claims 1 to 8 in automotive interior bonding and lagging.

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