Study On 4D Printing And Properties Of Self-healing Shape Memory Epoxy Resin

Shape memory materials have the characteristics of self-perception,self-regulation and self-adaptation,have become a research hotspot in the field of materials.Aiming at the problems of microcracks in the deformation process of shape memory materials,self-healing shape memory materials emerge as the times require,showing great application prospects in tissue engineering,biomedicine and intelligent structures.However,most self-healing shape memory materials have low mechanical strength and lack of deformation resistance,which makes it difficult to be applied in complex environment.The work of this thesis is mainly based on epoxy resin,adding self-healing microcapsules and stimulus response units to prepare 4D printed epoxy resin shape memory materials with self-healing,shape memory and deformation resistance by direct ink writing 3D printing technology.The main research contents and results of this thesis are as follows:（1）Thermal response shape memory epoxy resin with good mechanical strength and self-healing efficiency was designed and prepared,and formed by casting and direct ink writing 3D printing technology respectively.The results show that the self-healing shape memory epoxy resin has good self-healing performance and thermal response shape memory function.Microcapsules and latent curing agent Cu（MI）₄Br₂ endow the material with self-healing function.When the material is self-healing at 130℃ for 2 h,the self-healing efficiency of scratch and fracture reaches 87.23%and 89.97%,respectively,achieving high self-healing efficiency.At the same time,the material can realize simple shape change under the stimulation of external temperature,and successfully realize the preparation of 4D printed shape memory epoxy resin with self-healing function.（2）With the support of direct ink writing 3D printing technology,a magnetic-thermal dual-response self-healing shape memory modified epoxy resin was designed and prepared.The E-51-PUP modified epoxy resin showed high toughness and low glass transition temperature,which greatly improved the flexibility of epoxy resin in shape memory process.The scratch self-healing efficiency and fracture self-healing efficiency reached 86.5%and 91.2%,respectively,by adding self-healing microcapsules to the material.At the same time,the magnetic response unit Fe₃O₄@GO is introduced to realize the shape memory function of magnetic response and thermal response.Further experimental studies show that the self-healing 4D printed shape memory modified epoxy resin can be used in intelligent space deformation structures,temperature detectors and grippers.In summary,we achieved the construction of a self-healing 4D printed shape memory epoxy resin by incorporating self-healing microcapsules and stimulus response units and toughening modified epoxy resin.Its excellent universality may open up potential applications in textile,aerospace and automation.