基于多尺度方法的碳纳米管、石墨烯增强高分子基体的机械与摩擦学性能的机理研究

Carbon nanotubes and graphene sheets are become to be ideal nano-reinforcements for enhancing polymer materials due to their excellent mechanical and thermodynamic properties. Polymer matrices can hence be further promoted in advanced engineering applications. At present, investigations in this academic field are still relied on experimental approaches. Lack of understanding mechanisms of the mechanical and tribological properties of polymer nano-composites has been dedicated. In this project, it is aimed to develop a multi-scale investigation system and method by a combination of micro, meso and macro views. Molecular dynamics method will be introduced to reveal and analyze the enhancement mechanisms on the mechanical and tribological properties, failure mechanisms of polymer matrix reinforced by carbon nanotubes and graphene sheets from an atomic view. The modeling processes and calculating methods of coarse grained simulations will be defined and verified. The inherent mechanisms of influencing the structural properties and failures of polymer nano-composites will be explored and clarified by considerations of different needs of engineering applications from meso-scale. Experimental studies will be conducted to verify and optimize the theoretical models and calculation methods of molecular dynamics and coarse grained simulations. It is expected that variable failure criteria of polymer nano-composites can be proposed. Multi-scale theories of fracture failure, crack propagation and properties optimization of polymer nano-composites are expected to be established. The reliability of polymer nano-composites will be ensured in practical applications by different methods of structural design. The anticipated achievements hold promise for providing multi-scale methods for advancing and promoting the engineering applications of polymer composites reinforced by carbon nanotubes and graphene sheets.

碳纳米管和石墨烯凭借优异的力学和热力学等性能，成为高分子基体的理想纳米增强材料，推动了其在高精尖装备中的应用。目前该领域的探索大多集中在维度单一的实验研究，缺乏不同尺度下的相互支撑与验证，许多关键性的机理问题很难得到系统性和根本性的解决。本项目旨在开发贯穿微观、介观、宏观的多尺度探索体系与方法，基于分子动力学理论，从原子尺度揭示碳纳米高分子基体的机械与摩擦性能的增强机制、失效机理、性能变化规律及其调控机制等科学问题。明确高分子纳米复合材料粗粒化建模和计算方法，确定相关力场参数。在介观尺度下，结合工程实际，阐释高分子纳米复合结构性征与失效行为的影响机制。通过实验优化理论探索中的模型、参数与计算方法。提出和建立多尺度下复合材料的各项性能增强与结构失效的理论和准则，明确复合材料的结构优化和性能调控方式，确保其在实际应用中的可靠性，为推动碳纳米高分子复合材料的产业化提供坚实的多尺度理论基础。

碳纳米管和石墨烯凭借优异的力学和热力学等性能，成为高分子基体的理想增强材料，推动了其在高精尖装备中的应用。鉴于该领域的探索大多集中在维度单一的实验研究，缺乏不同尺度下的相互支撑与验证，许多如纳米材料团聚和分散行为等机理问题很难得到系统性和根本性的解决。本项目旨在开发贯穿微观、介观、宏观的多尺度探索方法与体系，探索材料因多尺度结构所衍生的一系列科学问题。申请人在该项目的执行期内基于并拓展了既定研究计划，基于分子动力学理论，从原子尺度揭示了碳纳米高分子基体的机械与摩擦性能的增强机制、失效机理、性能变化规律及其调控机制等科学问题，明确了纳米材料不同表面改性方式的优劣。介观尺度下确定了高分子纳米复合材料粗粒化建模和计算方法，确定了相关力场参数，并开发了基于有限元与分子模拟的代表性单元多尺度框架，结合工程实际，阐释了高分子纳米复合结构性征与力学行为的相互影响机制，揭示了纳米材料的分散机理。通过宏观实验，并基于理论成果的精确指导，成功制备了纳米橡胶复合材料，通过一系列表征手段，验证了制备方法的成熟性，明晰了官能化纳米材料的结构特性、分散机理和补强机制，形成了相互验证、相互优化的多尺度研究理论体系，明确了复合材料的结构优化和性能调控方式，可确保其在实际应用中的可靠性，也为推动碳纳米高分子复合材料的产业化提供坚实的多尺度理论基础。项目执行期内，共发表17篇高水平论文，申请2项发明专利，成果丰富且具有很高的科学价值。