Fabrication And Characterization Of Shape Memory Polymer With Self-healing Capability

In recent years, the rapid development of science and technology promotethe progress of human society. There are more and more types of materialsappeared in humans’ life, the intelligent and diversified development of materialshas become an irresistible historical trend. The shape memory polymers havepotential applications in many fields, such as aerospace, biomedical, textiles andour daily life based on their unique properties. However, SMPs can inevitablyproduce micro-cracks which have the potential to cause the failure of materialswhen they are processed and serviced, and the excellent performance of SMPscan’t be fully exploited. Therefore, to make the SMPs with self-healingcapability have caused general concern. This kind of materials can automaticallyrepair the internal cracks. It not only can extend the life of SMPs but also ensureits excellent capabilities.In this study, we use shape memory epoxy (SMEP) as matrix, andpolycaprolactone as self-healing agent,; synthesized a kind of smart materialswhich not only have shape memory effect but also have self-healing properties.Differential Scanning Calorimetry (DSC) and Thermogravimetric Analy sis (TGA)were employed for the thermal performance analysis, DMA were used toanalysized the thermo-mechanical properties. Scanning electron microscopy(SEM) was used for observing the crack morphology and Fourier transforminfrared spectroscopy (FTIR) discussed the self-healing mechanism.Self-healing performance of this material was investigated bysingle-edge-notched-beam (SENB) test.The results showed that the materials have excellent thermal properties, theglass transition temperature Tgranges from90℃~145℃, the thermaldecomposition starting temperature (TD) is higher than280℃, the materialsexhibits good heat resistance, and they are also have good mechanical property,the modulus of elasticity is up to3GPa at low temperature. The shape memorypolymers with self-healing capability have a significant viscoelastic. When thetemperature is equal to or higher than the materials Tg, a shape memory effectcan be observed, the shape fixed rate is higher than98%, the speed of shaperecovery is faster, and the shape recovery rate is greater than90%.The self-healing mechanism analysis found that self-healing is achieved bythe emergence of micro-phase separation during curing reaction and theremolding of thermoplastic PCL. Self-healing efficiency tests showed that the healing efficiency is up to69.33%were obtained for23.3%wt. PCL. After threeheating repair cycles, the average self-healing efficiency can be also reached39.22%, the materials can realize a repeatability of self-healing.