Automotive composite resin composition comprising a biomass-based material, automotive part comprising the composition, and vehicle comprising the automotive part

Abstract

The present disclosure relates to an automotive composite resin composition comprising a biomass-based material and exhibiting improved impact performance, an automotive part comprising the same, and a vehicle comprising the same.

Description

[0001] Cross-references to related applications This application claims the benefit of priority to Korean Patent Application No. 10-2025-0020516, filed with the Korean Intellectual Property Office on February 18, 2025, the entire disclosure of which is incorporated herein by reference. Technical Field

[0002] This disclosure relates to an automotive composite resin composition comprising a biomass-based material and exhibiting improved impact properties, an automotive component comprising the automotive composite resin composition, and a vehicle comprising the automotive component. Background Technology

[0003] In recent years, the automotive industry has increasingly prioritized not only lightweight design but also other factors such as impact resistance, thermal stability, and the use of environmentally friendly materials. This multifaceted focus reflects a shared effort to mitigate environmental impact while enhancing vehicle safety and performance. A significant aspect of this initiative is the proactive introduction of biomass-based materials, which offer sustainable alternatives to traditional petroleum-derived components. By integrating these environmentally friendly materials into automotive manufacturing, the industry aims to reduce its carbon footprint and promote a more circular economy.

[0004] Biomass comprises organic materials derived from organisms such as plants, animals, and microorganisms, and it offers significant advantages as a renewable resource that can effectively replace fossil fuels. Biomass contains a variety of components, including cellulose, lignin, hemicellulose, fats, and proteins, and is widely used in energy production, chemical manufacturing, and the production of high-performance materials. With increasing societal emphasis on sustainability and environmental protection, biomass-based materials are gaining significant attention as a viable alternative to minimizing greenhouse gas emissions and reducing dependence on fossil resources.

[0005] Cellulose nanofibers (CNFs) and lignin are two typical biomass materials proven to enhance physical properties and are increasingly used in the automotive industry. CNFs, a natural polymer with high mechanical strength and low density, are used in automotive components such as dashboards, panels, and seats. However, excessive introduction of CNFs can adversely affect flowability and fluidity during manufacturing, complicating injection molding. On the other hand, lignin enhances the structural strength of wood fibers and has significant potential as a carbon source in composites. However, over-reliance on lignin can impair the impact strength and durability of automotive components; therefore, careful trade-offs are needed in material selection to optimize performance and sustainability in automotive applications.

[0006] While biomass-based materials offer significant advantages as environmentally friendly and renewable alternatives, they also present several drawbacks that limit their applicability. For example, the hydrophilicity of biomass leads to its absorption of moisture, which subsequently reduces the mechanical strength and durability of composite materials. This sensitivity to moisture, coupled with its vulnerability to microorganisms, light, and heat, makes it less suitable for high-performance applications. Furthermore, biomass-based materials often exhibit relatively lower impact performance, particularly in impact strength, compared to conventional materials. Therefore, there is a need to develop material formulations and compositions that incorporate biomass components to enhance mechanical properties. Summary of the Invention

[0007] This disclosure aims to provide an environmentally friendly biomass-incorporated automotive composite resin composition that exhibits improved impact and thermal properties, as well as automotive parts comprising the composition and vehicles comprising the automotive parts.

[0008] One aspect of this disclosure provides an automotive composite resin composition comprising 20 to 40 parts by weight of a polyolefin-based resin and 25 to 30 parts by weight of a biomass-based material based on 100 parts by weight of the automotive composite resin composition.

[0009] In some embodiments, the biomass-based material includes one or more of cellulose nanofibers (CNF), polyhydroxyalkanoates (PHA), lignin, bio-based polyethylene (Bio-PE), or any combination thereof.

[0010] Another aspect of this disclosure provides an automotive component comprising an automotive composite resin composition according to various aspects of this disclosure.

[0011] Another aspect of this disclosure provides a vehicle that includes automotive components according to various aspects of this disclosure.

[0012] The automotive composite resin composition according to this disclosure contains at least 25 wt.% biomass-based material based on total weight, and is therefore environmentally friendly and meets the certification requirements for bio-based products.

[0013] In some embodiments, the automotive composite resin composition according to this disclosure comprises a biomass-based material that exhibits improved flowability and rheology, enabling smooth injection molding.

[0014] In some embodiments, automotive parts comprising the automotive composite resin composition according to the present disclosure exhibit improved impact performance.

[0015] In some embodiments, the automotive components according to this disclosure comprise biomass-based materials and exhibit improved strength, modulus of elasticity, and thermal properties. Detailed Implementation

[0016] Furthermore, unless otherwise expressly defined, the terminology used in the detailed implementation (including technical or scientific terms) should have the same meaning as commonly understood by those skilled in the art. It should also be understood that common terms should be interpreted as those conventionally used in the relevant field, and should not be interpreted in an idealized or overly formal sense unless otherwise expressly defined herein.

[0017] Furthermore, terms such as "first," "second," and other numerical terms are used only to distinguish one element from another. These terms are generally used only to distinguish one element from another. For example, without departing from the scope of this disclosure, a first element may be referred to as a second element, and similarly, a second element may be referred to as a first element.

[0018] The terminology used herein is for the purpose of describing particular exemplary embodiments only and is not intended to be limiting. The singular forms include the plural forms unless the context explicitly states otherwise. In the following description, the terms “comprising,” “including,” “having,” etc., indicate the presence of features, steps, elements, or combinations thereof, but should not be construed as excluding the presence or addition of one or more other features, steps, elements, or combinations thereof.

[0019] In some embodiments, the automotive composite resin composition disclosed herein comprises a polyolefin-based resin and a biomass-based material.

[0020] According to one embodiment of this disclosure, the polyolefin-based resin includes polypropylene (PP). In some embodiments, the polypropylene (PP) has a flowability of 50 to 150 g / 10 min.

[0021] In some embodiments, polypropylene has similar properties to polyethylene (PE), and compared to PE, polypropylene has a higher melting point, improved transparency, and improved flexibility. Furthermore, in some embodiments, polypropylene has improved mechanical properties, such as tensile and compressive strength, as well as improved thermal properties, including a low coefficient of thermal expansion and a high heat distortion temperature.

[0022] In some embodiments, the automotive composite resin composition according to the present disclosure comprises a polyolefin-based resin in an amount of 20 to 40 parts by weight based on 100 parts by weight of the automotive composite resin composition.

[0023] In some embodiments, the automotive composite resin composition disclosed herein comprises biomass-based materials.

[0024] Biomass is a collective term for organic materials derived from living organisms, such as plants, animals, and microorganisms. It can be used as polymer materials through chemical or biological synthesis and is environmentally friendly.

[0025] In some embodiments, the biomass-based material according to this disclosure comprises one or more of cellulose nanofibers (CNF), polyhydroxyalkanoates (PHA), lignin, bio-based polyethylene (Bio-PE), or any combination thereof.

[0026] In some embodiments, the automotive composite resin composition according to the present disclosure comprises a biomass-based material in an amount of 25 to 30 parts by weight based on 100 parts by weight of the automotive composite resin composition.

[0027] In some embodiments, the automotive composite resin composition according to this disclosure comprises biomass-based material in an amount of at least 25 wt.% of the total weight, thereby meeting the certification requirements for bio-based products.

[0028] Globally, bio-based products are certified according to the ASTM D6866 testing standard, and each country implements a bio-based product certification system based on biomass content.

[0029] In South Korea, products containing at least 25 wt.% biomass by weight are certified according to ASTM D6866 testing. Specifically, transparent and foamed products are certified when they contain at least 15 wt.% biomass by weight. Furthermore, bio-based synthetic resin products are certified when they contain at least 25 wt.% biomass by weight.

[0030] However, South Korea's bio-based products differ slightly from international standards in that they do not contain natural polymers such as starch, cellulose, and wood flour.

[0031] In other words, although certification standards for bio-based materials vary from country to country, a product can be certified as a bio-based product internationally when the content of bio-based materials is 20 to 25 wt.% or more of the total weight. Therefore, in some embodiments, the automotive composite resin composition according to this disclosure meets the certification requirements for bio-based products based on international standard specifications.

[0032] In some embodiments, the biomass-based materials disclosed herein comprise cellulose nanofibers (CNF).

[0033] Cellulose nanofibers (CNFs) are a material derived from natural resources that exhibits high strength and light weight, which can help reduce the weight of automotive composite resin compositions.

[0034] In one embodiment of this disclosure, the automotive composite resin composition comprises cellulose nanofibers in an amount of 7 to 13 parts by weight per 100 parts by weight of the automotive composite resin composition.

[0035] In some embodiments, when the content of cellulose nanofibers in the automotive composite resin composition of this disclosure is less than 7 parts by weight per 100 parts by weight of the automotive composite resin composition, the improvement in the overall mechanical properties of the composition is not significant. In some embodiments, when the content of cellulose nanofibers in the automotive composite resin composition of this disclosure is more than 13 parts by weight per 100 parts by weight of the automotive composite resin composition, the flowability and rheology may deteriorate, which is detrimental to injection molding.

[0036] In one embodiment of this disclosure, the automotive composite resin composition comprises cellulose nanofibers based on 100 parts by weight of a biomass-based material, in a content of 20 to 35 parts by weight.

[0037] In some embodiments, cellulose nanofibers are introduced as 50% masterbatch during the manufacture of the automotive composite resin composition disclosed herein to ensure the aforementioned content ratio in the final composition. Hereinafter, 50% masterbatch means that the cellulose nanofibers are contained in the masterbatch at a concentration of 50%, and the aforementioned weight range of cellulose nanofibers may correspond to half the actual weight portion introduced.

[0038] In other words, in some embodiments, the actual amount of cellulose nanofibers introduced for preparing the automotive composite resin composition of this disclosure is twice the specified weight range.

[0039] The biomass-based materials disclosed herein include polyhydroxyalkanoates (PHA).

[0040] Polyhydroxy fatty acid esters (PHAs) are biodegradable polymers synthesized by microorganisms in nature and have improved thermal stability.

[0041] In one embodiment of this disclosure, the automotive composite resin composition comprises a polyhydroxyalkanoate in an amount of 3 to 7 parts by weight based on 100 parts by weight of the automotive composite resin composition.

[0042] In some embodiments, when the content of polyhydroxyalkanoate in the automotive composite resin composition of this disclosure is less than 3 parts by weight per 100 parts by weight of the automotive composite resin composition, the improvement in thermal properties is not significant. In some embodiments, when the content of polyhydroxyalkanoate in the automotive composite resin composition of this disclosure is more than 7 parts by weight per 100 parts by weight of the automotive composite resin composition, the overall mechanical strength of the composition decreases.

[0043] In one embodiment of this disclosure, the automotive composite resin composition comprises a polyhydroxyalkanoate in an amount of 10 to 20 parts by weight based on 100 parts by weight of biomass-based material.

[0044] The biomass-based material disclosed herein contains lignin.

[0045] Lignin is a natural polymer that binds with cellulose in wood, enhancing its structural strength and exhibiting improved heat and chemical resistance.

[0046] In one embodiment of this disclosure, the automotive composite resin composition comprises lignin in an amount of 7 to 13 parts by weight based on 100 parts by weight of the automotive composite resin composition.

[0047] When the lignin content of the automotive composite resin composition disclosed herein is less than 7 parts by weight per 100 parts by weight of the automotive composite resin composition, the content of biomass-based materials decreases, making it difficult to meet the aforementioned certification standards for bio-based products. When the lignin content of the automotive composite resin composition disclosed herein exceeds 13 parts by weight per 100 parts by weight of the automotive composite resin composition, impact performance and environmental testing performance may deteriorate significantly.

[0048] In one embodiment of this disclosure, the automotive composite resin composition comprises lignin, which is based on 100 parts by weight of biomass-based material and has a content of 20 to 35 parts by weight.

[0049] Bio-based polyethylene (Bio-PE) is polyethylene produced from ethanol derived from biomass (such as sugarcane) rather than from existing petroleum-based sources. It is environmentally friendly and exhibits the same physical properties as existing petroleum-based polyethylene.

[0050] In one embodiment of this disclosure, the automotive composite resin composition comprises bio-based polyethylene in an amount of 3 to 10 parts by weight based on 100 parts by weight of the automotive composite resin composition.

[0051] In some embodiments, when the content of bio-based polyethylene in the automotive composite resin composition of this disclosure is less than 3 parts by weight per 100 parts by weight of the automotive composite resin composition, the mechanical properties cannot be adequately guaranteed. In some embodiments, when the content of bio-based polyethylene in the automotive composite resin composition of this disclosure is more than 10 parts by weight per 100 parts by weight of the automotive composite resin composition, the performance of polyethylene is excessively prominent, which may disrupt the overall balance of the biomass-based material.

[0052] In one embodiment of this disclosure, the automotive composite resin composition comprises bio-based polyethylene in an amount of 15 to 30 parts by weight based on 100 parts by weight of bio-based material.

[0053] In some embodiments, the automotive composite resin composition of this disclosure further comprises a stiffening agent. In one embodiment, the stiffening agent comprises one or more of cellulose fibers, basalt fibers, glass fibers, carbon fibers, or any combination thereof. The above materials are examples, and the types of stiffening agents in this disclosure are not limited thereto.

[0054] In one embodiment of this disclosure, the automotive composite resin composition includes a stiffness reinforcing agent in an amount of 10 to 20 parts by weight based on 100 parts by weight of the automotive composite resin composition.

[0055] In some embodiments, when the content of the stiffening agent contained in the automotive composite resin composition of this disclosure is less than 10 parts by weight per 100 parts by weight of the automotive composite resin composition, it is difficult to achieve high stiffness performance. In some embodiments, when the content of the stiffening agent contained in the automotive composite resin composition of this disclosure is more than 20 parts by weight per 100 parts by weight of the automotive composite resin composition, the flowability and rheological properties deteriorate, and it is difficult to achieve weight reduction.

[0056] Furthermore, the automotive composite resin composition disclosed herein also includes an impact modifier. In one embodiment, the impact modifier includes one or more of the following: α-olefin copolymers, terpolymers, styrene-butadiene rubber (SBR), ethylene-octene elastomers (EOE), styrene-ethylene-butene-styrene copolymers (SEBS), or any combination thereof, with a carbon number ranging from 3 to 8. The above materials are examples, and the types of impact modifiers in this disclosure are not limited thereto.

[0057] In one embodiment of this disclosure, the automotive composite resin composition includes an impact modifier in an amount greater than 10 parts by weight and less than 30 parts by weight per 100 parts by weight of the automotive composite resin composition.

[0058] In some embodiments, when the content of the impact modifier included in the automotive composite resin composition of this disclosure is 10 parts by weight or less based on 100 parts by weight of the automotive composite resin composition, the improvement in impact performance is not significant. In some embodiments, when the content of the impact modifier included in the automotive composite resin composition of this disclosure is 30 parts by weight or more based on 100 parts by weight of the automotive composite resin composition, the thermal properties deteriorate.

[0059] In some embodiments, the automotive composite resin compositions of this disclosure further comprise a compatibilizer. The compatibilizer can enhance the compatibility between polymers with different properties, thereby preventing deterioration of physical properties.

[0060] In one embodiment, the compatibilizer is a polyolefin-based resin containing furan groups. For every 100 parts by weight of the polyolefin, the compatibilizer contains 0.3 to 2 parts by weight of furan groups.

[0061] However, this is merely an example, and the types of compatibilizers used in this disclosure are not limited to this.

[0062] In some embodiments, the compatibilizer has a flowability of 50 to 150 g / 10 min.

[0063] In some embodiments, the automotive composite resin composition according to this disclosure further comprises other additives. In this disclosure, other additives include one or more of antioxidants, light stabilizers, colorants, lubricants, antistatic agents, or any combination thereof. In some embodiments, the other additives are commercially available additives and are not limited to specific types. Any additive that can be introduced into the automotive composite resin composition to improve its physical properties can be used as other additives in this disclosure.

[0064] The automotive component according to this disclosure comprises the automotive composite resin composition of the various embodiments described above.

[0065] The vehicle according to this disclosure includes the automotive components described in the various embodiments above. Therefore, the vehicle is both environmentally friendly and has improved mechanical properties.

[0066] The present disclosure will now be described in more detail through embodiments. However, the embodiments and experimental examples provided below are only for describing the present disclosure in more detail, and the scope of the present disclosure is not limited to the embodiments and experimental examples below.

[0067] Examples and Comparative Examples The composition preparation examples and comparative examples are listed in Table 1 below. The specific compositions of Examples 1 and 2 and Comparative Examples 1 to 6 are as follows.

[0068] Polypropylene resin (hereinafter referred to as PP in Table 1) is used as the polyolefin-based resin. Glass fibers with an average diameter of 10 μm and a polysiloxane-treated surface are used as the stiffness reinforcing agent. A combination of ethylene-octene elastomer and styrene-ethylene-butene-styrene copolymer elastomer (both thermoplastic elastomers) is used as the impact modifier. Maleic anhydride-grafted modified polypropylene (PP) is used as the compatibilizer. Antioxidants and weather stabilizers are used as other additives.

[0069] Table 1 Experimental Example The physical properties of the automotive composite resin compositions according to Examples 1 and 2 and Comparative Examples 1 to 6 were evaluated. The melt flow index (MFI), tensile strength, flexural strength, flexural modulus, impact strength, and heat distortion temperature of the automotive composite resin compositions in the Examples and Comparative Examples were determined.

[0070] The evaluation of each physical property is based on the following tests and conditions.

[0071] 1) Melt Flow Index (MFI): ISO 1133-1 (2.16 kg@230℃) 2) Tensile strength: ISO 527 (50 mm / min) 3) Bending strength and bending modulus: ISO 178 (2 mm / min) 4) Impact strength: ISO 180 (2.94 J) 5) Heat distortion temperature (HDT): ISO 75 (0.45MPa).

[0072] The evaluation results of the physical properties of Examples 1 and 2 and Comparative Examples 1 to 6 are shown in Table 2 below.

[0073] Table 2 Referring to Table 2, it can be seen that the automotive composite resin compositions in Examples 1 and 2 exhibited improved performance compared to Comparative Examples 1 to 6.

[0074] First, the heat distortion temperature of the automotive composite resin composition in Comparative Example 1 was 139°C, indicating poorer thermal properties compared to the automotive composite resin compositions in Examples 1 and 2. This result is due to the higher content of bio-based polyethylene (Bio-PE) in the automotive composite resin composition of Comparative Example 1. Table 2 confirms that the automotive composite resin compositions in the examples exhibit higher stability at high temperatures. This result further demonstrates the importance of achieving a proper balance or formulation of biomass-based materials.

[0075] Comparative Example 2 exhibited a lower melt flow index (MFI) than Examples 1 and 2. This result was due to the increased cellulose nanofiber (CNF) content in Comparative Example 2. Table 2 confirms that the automotive composite resin compositions in the examples exhibited improved processing properties due to the balanced composition of biomass-based materials.

[0076] Compared to Examples 1 and 2, Comparative Example 3 contained an excessive amount of impact modifier, resulting in poorer thermal properties (heat distortion temperature: 135°C). Conversely, compared to Examples 1 and 2, Comparative Example 4 contained a lower amount of impact modifier, resulting in poorer impact properties (impact strength: 7 kJ / m²).

[0077] In Comparative Examples 5 and 6, no other biomass-based materials were contained besides cellulose nanofibers. Therefore, the content of biomass-based materials in Comparative Examples 5 and 6 did not exceed 25 wt.% of the total weight of the composition, and thus did not meet the certification standards for bio-based products. Furthermore, Comparative Example 5 exhibited lower tensile and flexural strength, while Comparative Example 6 exhibited poorer flowability and impact strength.

[0078] The above experiments confirmed that the automotive composite resin compositions in Examples 1 and 2 contain a certain amount or more of biomass-based materials, thus meeting the certification standards for bio-based products. Furthermore, the appropriate proportions of biomass-based materials in the automotive composite resin compositions in Examples 1 and 2 ensured improvements in all the physical properties required for automotive composite resin compositions.

[0079] Although this disclosure has been described with reference to embodiments, various changes or modifications can be made by those skilled in the art. In this regard, those skilled in the art should understand that various changes in form and detail may be made to this disclosure without departing from the scope of this disclosure. Therefore, the disclosed embodiments should be considered descriptive rather than restrictive. The scope of the disclosure is not limited by the foregoing detailed description but by the appended claims, and all differences within the scope should be interpreted as included in the disclosure.

Claims

1. An automotive composite resin composition comprising, based on 100 parts by weight, said automotive composite resin composition: (i.) 20 to 40 parts by weight of polyolefin-based resin; (ii.) 25 to 30 parts by weight of biomass-based material, and in, The biomass-based material includes one or more of cellulose nanofibers (CNF), polyhydroxyalkanoates (PHA), lignin, bio-based polyethylene (Bio-PE), or any combination thereof.

2. The automotive composite resin composition according to claim 1, wherein the polyolefin-based resin comprises polypropylene (PP) with a flowability of 50 to 150 g / 10 min.

3. The automotive composite resin composition according to claim 1, wherein the content of cellulose nanofibers (CNF) is 7 to 13 parts by weight per 100 parts by weight of the automotive composite resin composition.

4. The automotive composite resin composition according to claim 1, wherein the content of cellulose nanofibers (CNF) is 20 to 35 parts by weight based on 100 parts by weight of the biomass-based material.

5. The automotive composite resin composition according to claim 1, wherein the content of the polyhydroxyalkanoate (PHA) is 3 to 7 parts by weight based on 100 parts by weight of the automotive composite resin composition.

6. The automotive composite resin composition according to claim 1, wherein, The content of the polyhydroxyalkanoate (PHA) is 10 to 20 parts by weight per 100 parts by weight of the biomass-based material.

7. The automotive composite resin composition according to claim 1, wherein, The lignin content is 7 to 13 parts by weight per 100 parts by weight of the automotive composite resin composition.

8. The automotive composite resin composition according to claim 1, wherein, The lignin content is 20 to 35 parts by weight per 100 parts by weight of the biomass-based material.

9. The automotive composite resin composition according to claim 1, wherein, The content of the bio-based polyethylene (Bio-PE) is 3 to 10 parts by weight per 100 parts by weight of the automotive composite resin composition.

10. The automotive composite resin composition according to claim 1, wherein, The content of the bio-based polyethylene (Bio-PE) is 15 to 30 parts by weight per 100 parts by weight of the biomass-based material.

11. The automotive composite resin composition according to claim 1, further comprising a stiffening agent in an amount of 10 to 20 parts by weight based on 100 parts by weight of the automotive composite resin composition, wherein the stiffening agent comprises one or more of cellulose fiber, basalt fiber, glass fiber, carbon fiber, or any combination thereof.

12. The automotive composite resin composition according to claim 1, further comprising an impact modifier in an amount greater than 10 parts by weight and less than 30 parts by weight per 100 parts by weight of the automotive composite resin composition, wherein the impact modifier comprises one or more of an α-olefin copolymer, a terpolymer, a styrene-butadiene rubber (SBR), an ethylene-octene elastomer (EOE), a styrene-ethylene-butene-styrene copolymer (SEBS), or any combination thereof, having a carbon number of 3 to 8.

13. An automotive component comprising the automotive composite resin composition according to any one of claims 1-12.

14. A vehicle comprising the automotive component of claim 13.

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