Epoxy vitrimers based on dynamic covalent bond chemistry have been developed in recent years as they can solve the problem of recycling and reuse for traditional thermosetting materials. Lignin as an aromatic raw material has recently used to partially replace commercial diglycidyl ether bisphenol A (DGEBA) in the epoxy vitrimers, however, it is difficult to achieve high lignin replacement rate, excellent mechanical property and reprocessability in a facile method at the same time. In this work, high mechanical strength and lignin replacement rate of lignin-based vitrimers were successfully synthesized by gradually replacing DGEBA with glycidyl ether of lignin. The mechanical properties of the lignin-based epoxy vitrimers can be tuned by different ratios of glycidyl ether of lignin and DGEBA, the Young’s modulus and tensile strength of those vitrimers can reach up to 2.00 GPa and 46.8 MPa, respectively. It's worth noting that the tensile strength and elongation at break were 39.5 MPa and 5.81 % when the lignin replacement rate was 100 %. All the lignin-based epoxy vitrimers exhibit excellent self-healing, reprocessing and shape memory property. The crack widths of the vitrimers were repaired over 80 % in just 5 min at 160 ℃, the tensile strength can reach up to 97 % healing efficiency after being hot reprocessed. The great properties of lignin-based epoxy vitrimers indicate that they can be used as renewable alternatives for bisphenol A epoxy vitrimers.

近年来，已经开发出基于动态共价键化学的环氧三聚体，因为它们可以解决传统热固性材料的回收和再利用问题。木质素作为芳香族原料最近已用于部分替代环氧微晶粉中的商业二缩水甘油醚双酚A（DGEBA），但是，难以同时以简便的方法实现高木质素替代率，优异的机械性能和可再加工性。在这项工作中，通过用木质素的缩水甘油醚逐渐取代DGEBA，成功地合成了高机械强度和木质素基三聚体的木质素替代率。木质素基环氧微晶胶的机械性能可通过木质素缩水甘油醚和DGEBA的不同比例进行调节，这些三元共聚物的杨氏模量和拉伸强度分别可以达到2.00 GPa和46.8 MPa。值得注意的是，当木质素替代率为100％时，拉伸强度和断裂伸长率分别为39.5 MPa和5.81％。所有木质素基环氧微晶聚合物均具有出色的自修复，再加工和形状记忆性能。在160℃短短5min内修复了陶瓷裂纹的宽度超过80％，热加工后的拉伸强度可以达到97％的修复效率。木质素基环氧微晶胶的出色性能表明，它们可用作双酚A环氧微晶胶的可再生替代品。木质素替代率为100％时为81％。所有木质素基环氧微晶聚合物均具有出色的自修复，再加工和形状记忆性能。在160℃短短5min内修复了陶瓷裂纹的宽度超过80％，热加工后的拉伸强度可以达到97％的修复效率。木质素基环氧微晶胶的出色性能表明，它们可用作双酚A环氧微晶胶的可再生替代品。木质素替代率为100％时为81％。所有木质素基环氧微晶聚合物均具有出色的自修复，再加工和形状记忆性能。在160℃短短5min内修复了陶瓷裂纹的宽度超过80％，热加工后的拉伸强度可以达到97％的修复效率。木质素基环氧微晶胶的出色性能表明，它们可用作双酚A环氧微晶胶的可再生替代品。