液晶弹性体是一种可以在热、电、光等外界刺激下发生可逆形变的智能材料。将动态共价键引入到液晶弹性体中，不仅提供了一种简单高效获得较大尺寸单畴液晶弹性体驱动器的方法，还可以赋予材料再加工、循环回收、自修复等功能。利用网络的动态性，还可以实现液晶弹性体驱动器驱动模式的重编程和复杂驱动模式的构筑。此外，近两年发现的自生长现象进一步丰富了液晶弹性体驱动器的功能，其无需外界刺激或能量输入便可实现生长的特殊性能为驱动器的设计提供了新的思路。但现有液晶弹性体驱动器的性能仍有进一步提升的空间。自生长的驱动行为仅限于新制样品，为材料的保存及应用带来操作难度；多数液晶弹性体力学性能较弱，刚度较低，因此而缺乏承载力和抗变形能力；动态共价键的引入导致网络稳定性降低，影响材料的长期稳定使用。这些问题制约了液晶弹性体驱动器的实际应用。针对上述问题，本论文基于含动态共价键液晶弹性体，利用动态交换反应，调整已失活自生长液晶弹性体的网络拓扑结构，使其恢复活性；将液晶弹性体与低熔点合金相结合，利用动态共价键使液晶弹性体获得取向，制备可变刚度复合驱动器；通过引入热潜伏催化剂，调控网络动态交换的活性，实现驱动稳定性与再加工性的兼顾。本论文的研究工作主要分为以下三个部分：（1）针对失活的自生长液晶弹性体，通过溶胀的方式引入酯交换催化剂，在溶剂和网络动态交换双重作用下，将失活和已生长样品还原为初始状态，恢复自生长活性，并有效地擦除已生长样品的生长历史；探究了再活化过程的影响因素并提出再活化过程的机理；通过对样品进行选择性的再活化，实现了自生长的区域控制。（2）针对液晶弹性体材料刚度较低的问题，制备了液晶弹性体-低熔点合金复合材料；利用动态共价键实现交联后的取向，从而制备复合驱动器；利用低熔点合金熔融前后的变化，赋予复合驱动器可变刚度的性能；利用高刚度带来的承载力和抗变形能力，结合驱动性能，开发了液晶弹性体材料的新的应用场景。（3）针对动态共价键带来的网络稳定性与再加工性之间的矛盾，通过引入热潜伏催化剂，实现了动态交换活性的调控；通过选择性激活催化剂，实现了材料的局部取向；通过控制潜伏性催化剂的激活程度，实现了复杂驱动模式的构筑。

Liquid crystalline elastomers are intelligent materials that undergo reversible deformation under external stimuli such as heat, electricity, and light. By introducing dynamic covalent bonds into liquid crystalline elastomers, not only a simple and efficient method for obtaining large-sized liquid crystalline elastomer actuators is provided, but also functionalities such as material reprocessing, recycling, and self-healing can be endowed. Utilizing the dynamic nature of the network, it is also possible to achieve reprogramming of the actuation modes and construction of complex actuation modes for liquid crystalline elastomer actuators. Additionally, the phenomenon of self-growth discovered in the recent two years has further enriched the functionality of liquid crystalline elastomer actuators. The ability to grow without the need for external stimuli or energy input provides new ideas for designing actuators. However, there remains potential for further enhancement in the performance of liquid crystalline elastomer actuators. The self-growing ability is limited to only fresh samples, which brings operational difficulties for material preservation and application. Most liquid crystalline elastomers exhibit relatively weak mechanical properties and low stiffness, resulting in a lack of load-bearing capacity and resistance to deformation. The introduction of dynamic covalent bonds leads to a decrease in network stability, affecting the long-term stable use of the material. These issues constrain the practical applications of liquid crystalline elastomer actuators.To address the aforementioned problems, this thesis focuses on liquid crystalline elastomers containing dynamic covalent bonds. By utilizing dynamic exchange reactions, the network topology of inactive self-growing liquid crystalline elastomers is adjusted to restore their self-growing ability. Liquid crystalline elastomers are combined with low-melting-point alloys, and oriented using dynamic covalent bonds to prepare composite actuators with variable stiffness. By introducing thermal latent catalysts, the dynamic activity of network is regulated to achieve a balance between actuation stability and reprocessing capability. The research work of this thesis is mainly divided into the following three parts:(1) For inactive self-growing liquid crystalline elastomers, transesterification catalyst was introduced through swelling, and under the synergistic action of solvent and network dynamic exchange, inactive and already grown samples were rejuvenated. They were reset to their initial state, restoring self-growing ability and effectively erasing the growth history of already grown samples. The influencing factors of the rejuvenation process were explored, and the mechanism of the rejuvenation process was proposed. Selective rejuvenation of samples was achieved to realize local control of self-growth.(2) To address the issue of lack of stiffness in liquid crystalline elastomer materials, liquid crystalline elastomer-low melting point alloy composites were prepared. Dynamic covalent bonds were used for orientation after crosslinking, thereby preparing composite actuators. Composite actuators were endowed with the performance of variable stiffness through the changes before and after the melting of low melting point alloys. New application scenarios of liquid crystalline elastomer materials were developed utilizing the load-bearing capacity and deformation resistance brought by high stiffness.(3) To address the contradiction between network stability and reprocessability brought by dynamic covalent bonds, the regulation of dynamic exchange activity was achieved by introducing thermal latent catalysts. Selective activation of catalysts realized local orientation control of materials. By controlling the degree of activation of latent catalysts, the construction of complex actuation modes was achieved.