Preparation And Multifunctional Application Of Intrinsic Self-healing/Healable Polyurethane/Urea

After suffering from injury,the organism can heal the wound autonomously without external stimulation.Inspired by this property,researchers developed a series of selfhealing/healable polymers.The intrinsic self-healing is based on the reconstruction of dynamic covalent bonding or non-covalent bonding to achieve repair,which can theoretically achieve an infinite number of repair processes and has a broader prospect than external one.Polyurethane/urea is one of the most important intrinsic healable materials.In this paper,two synthesis strategies of self-healing/healable polyurethane/urea are proposed,which are expected to be applied in the fields of protective materials and flexible thermal conductive materials.(1)Colorless and healable polyurethane/urea elastomer was prepared.Based on the unique hard phase structure of loose accumulation of asymmetric alicyclic rings,the elastomer has ultrahigh toughness and energy dissipation ability,which makes it widely used in the field of protective materials,and can realize self-healing under the induction of trace solvents.(2)A design scheme of high thermal conductivity composite material is proposed.The composite prepared by implanting hydroxylated boron nitride nanosheets into self-healing elastomer materials has high thermal conductivity,stability,self-healing ability at high temperature,electrical insulation and water vapor resistance,which make the composite possesses great potential in flexible electrical insulation and thermal interface materials.