Rational Design of High-Performance Nanomaterials for Electric Vehicle Tires
At a Glance
Section titled âAt a Glanceâ| Metadata | Details |
|---|---|
| Publication Date | 2023-07-27 |
| Journal | Highlights in Science Engineering and Technology |
| Authors | Zichen Liu |
| Institutions | Wuhan Institute of Technology |
| Citations | 2 |
| Analysis | Full AI Review Included |
Executive Summary
Section titled âExecutive SummaryâThis research focuses on rationally designing high-performance nanomaterials to address the critical limitations of electric vehicle (EV) tires: poor wear resistance and excessive rolling resistance.
- Core Value Proposition: Nanofiller hybridization (Silica and Nano-Diamond) is used to simultaneously reduce elastic hysteresis loss (the primary cause of rolling resistance) and enhance mechanical strength and thermal management.
- Rolling Resistance Mitigation: The use of modified Silica (Silica-Si-69-0.6, 600 nm particle size) significantly reduces the Payne effect and filler network reconstruction under periodic stress, resulting in the lowest measured compression heat generation (16.38 °C rise).
- Wear Resistance Improvement: Uniformly dispersed carboxylated Nano-Diamond (COOH-ND) enhances the cross-linking density of the SBR/BR matrix, effectively impeding polymer chain movement and improving overall wear resistance.
- Thermal Management: Nano-Diamond (ND) incorporation leverages its exceptional thermal conductivity (~3000 W/mK) to improve heat transfer, reducing local temperature buildup and prolonging tire service life.
- Performance Benchmark: The optimized Silica-Si-69-0.6 system achieved a permanent deformation of only 3.24%, drastically outperforming traditional Carbon Black N330 (39.85%) under the same fatigue conditions.
- Methodology: The process involves surface modification of ND via carboxylation and silanization (using MPTMS) to ensure strong chemical and physical adsorption with the rubber molecular chains.
- Environmental Concern: The paper concludes by highlighting the urgent need for research into the environmental pollution risks associated with the release of these nanomaterials through tire wear.
Technical Specifications
Section titled âTechnical Specificationsâ| Parameter | Value | Unit | Context |
|---|---|---|---|
| Rolling Resistance Contribution | 90-95 | % | Proportion of total tire rolling resistance attributed to elastic hysteresis loss. |
| ND Thermal Conductivity | ~3000 | W/mK | Thermal conductivity of Nano-Diamond (ND) used for heat dissipation. |
| SBR/BR Weight Ratio | 75/25 | N/A | Weight ratio of Styrene Butadiene Rubber (SBR) to Butadiene Rubber (BR) in the tread compound. |
| CB N330 Particle Size | 0.03 | ”m | Particle size of standard Carbon Black filler. |
| Silica-Si-69-0.6 Particle Size | 600 | nm | Particle size of the optimized surface-modified Silica filler. |
| CB N330 Fatigue Temp Rise | 39.3 | °C | Compression heat generation (stroke: 4.45 mm) for Carbon Black N330 composite. |
| Silica-Si-69-0.6 Fatigue Temp Rise | 16.38 | °C | Lowest compression heat generation observed for the optimized Silica composite. |
| CB N330 Permanent Deformation | 39.85 | % | Permanent deformation under periodic stress for Carbon Black N330 composite. |
| Silica-Si-69-0.6 Permanent Deformation | 3.24 | % | Lowest permanent deformation observed for the optimized Silica composite. |
| MPTMS Hydrolysis pH | 3.5-4.5 | N/A | pH range for the hydrolysis of (3-Mercaptopropyl) trimethoxysilane (MPTMS). |
| Silanization Temperature | 68 | °C | Temperature used for the silanization of COOH-ND. |
Key Methodologies
Section titled âKey Methodologiesâ- Nano-Diamond (ND) Carboxylation: Exposed ND was treated with hot air to achieve surface carboxylation (COOH-ND), preparing the surface for subsequent chemical modification.
- Silane Hydrolysis: (3-Mercaptopropyl) trimethoxysilane (MPTMS) was hydrolyzed in an ethanol/water mixture at 25 °C for 2 hours, maintaining a pH of 3.5-4.5.
- ND Silanization: The hydrolyzed MPTMS was reacted with the COOH-ND surface at 68 °C for 24 hours to create Silanized-ND (S-ND), ensuring strong chemical linkage potential with the rubber matrix.
- Composite Preparation: The SBR/BR rubber matrix was prepared using a 75/25 weight ratio. Half Silica, silane, half aromatic oil, and half process resin were added alongside the S-ND filler.
- Mixing and Vulcanization: A two-roll grinder was employed to mix the components, promoting a sufficient silanization reaction and uniform dispersion of the hybrid fillers (S-ND/SiO2) before the final vulcanization process.
- Structural Characterization: Fourier Transform Infrared Spectroscopy (FTIR) was used to confirm the successful carboxylation and silanization of ND. Field Emission Scanning Electron Microscopy (FESEM) was used to visualize the dispersion state of the nano-SiO2 and S-ND particles.
- Dynamic Performance Testing: Compression heat generation and permanent deformation were measured under periodic pressure (4.45 mm stroke) to quantify the elastic hysteresis loss (Payne effect) of the resulting NR vulcanizates.
Commercial Applications
Section titled âCommercial Applicationsâ- Electric Vehicle (EV) Tire Manufacturing: Direct application in developing âgreen tiresâ for EVs, focusing on maximizing battery range by minimizing rolling resistance while maintaining high safety standards (wet traction and wear).
- High-Durability Rubber Products: Use of ND/Silica hybrid fillers in industrial rubber goods (e.g., heavy-duty conveyor belts, industrial seals, and vibration dampeners) where high thermal stability and resistance to fatigue failure are critical.
- Advanced Nanofiller Production: Commercialization of surface-modified Silica (e.g., Silica-Si-69-0.6) and functionalized Nano-Diamond for use as superior reinforcing agents in polymer composites, offering low hysteresis loss compared to traditional Carbon Black.
- Sustainable Materials Engineering: Development of manufacturing processes that minimize the environmental release of nanomaterials during tire production and wear, addressing the identified risk of nano-pollutants accumulating in the environment.
- Tire Tread Formulation Optimization: Utilizing the established relationship between filler particle size (e.g., 600 nm modified Silica) and dynamic performance (low Payne effect) to create new, energy-efficient tire tread recipes.
View Original Abstract
In todayâs society, the market limitations of electric vehicle tires are relatively poor wear resistance and rolling resistance. These two problems restrict the further development of electric vehicles, accelerate energy consumption and environmental pollution, and bring hidden dangers to users. In this paper, the principle of tire wear resistance and the cause of excessive rolling resistance related to tire deformation are analyzed from the perspective of materials. At present, these two problems can be improved by adding nanomaterials to automobile tire materials (natural rubber and synthetic rubber). The tireâs thermal conductivity and wear resistance can be improved by inserting Silica and a small amount of nano-diamond. This paper will also discuss the unique advantages of carbon black with different particle sizes as filler by analyzing the effects of modified Silica and carbon black on the molecular rubber chain. On this basis, this paper will also explain the drawbacks of nanofiller materials.