The hierarchical and anisotropic mechanical behavior requirement of load-bearing soft tissues limits the utility of conventional elastomeric materials as a replacement for soft-tissue materials. Liquid-crystal elastomers (LCEs) have the potential to excel in this regard owing to its unique combination of mesogenic order in an elastomeric network. In this study, the mechanical behavior of the LCEs relevant to load-bearing biomedical applications was explored. LCEs with different network orientations (i.e., mesogen alignments) were investigated by fabricating the LCEs with polydomain and monodomain configurations. The polydomain and monodomain LCEs with the same degree of network crosslinking demonstrated diverse mechanical behavior, ranging from highly stiff and elastic nature to high damping capacity, depending on the loading direction with respect to the network alignment. The LCEs were also capable of matching the anisotropic mechanical behavior of an intervertebral disc. Additional studies were conducted on the in vivo biological response of LCEs upon subcutaneous implantation, as well as on the effect of the exposure to an in vitro simulated physiological environment on the mechanical behavior. The LCEs’ mechanical response was negligibly affected when exposed to biomedically relevant conditions. Furthermore, the solid and porous LCEs did not show any adverse effect on the surrounding tissues when implanted subcutaneously in rats. The biological response allows for tissue ingrowth and helps illustrate their utility in implantable biological devices. Finally, the utility of LCEs to mimic the mechanical function of biological tissue such as intervertebral disc was demonstrated by fabricating a proof of concept total disc replacement device.

承受载荷的软组织的分层和各向异性的机械性能要求限制了常规弹性体材料作为软组织材料的替代品的用途。液晶弹性体（LCE）由于其在弹性体网络中介晶顺序的独特组合而具有在这方面出色的潜力。在这项研究中，探讨了与承重生物医学应用有关的LCE的力学行为。通过制造具有多域和单域配置的LCE，研究了具有不同网络方向（即，液晶元排列）的LCE。具有相同网络交联度的多域和单域LCE表现出多种机械行为，从高刚性和弹性到高阻尼能力，取决于相对于网络对齐的加载方向。LCE还能够匹配椎间盘的各向异性力学行为。进一步的研究进行了皮下植入后LCE的体内生物学反应，以及暴露于体外模拟生理环境对机械行为的影响。当暴露于生物医学相关条件时，LCE的机械反应受到的影响可忽略不计。此外，当将其皮下植入大鼠中时，固体和多孔LCE对周围组织没有显示任何不利影响。生物反应使组织向内生长，并有助于说明其在可植入生物装置中的效用。最后，通过制造概念验证的全椎间盘置换装置，证明了LCE可以模仿诸如椎间盘等生物组织的机械功能。