Preparation And Properties Of Transition Metal Carbide/Nitride(MXene)-polymer Nanocomposites

Transition metal carbide/nitride(MXene)is an emerging two-dimensional nanomaterials with special surface chemistry and outstanding electrical properties.Due to the introduction of a large number of oxygen-containing and fluorine-containing functional groups in the preparation process,the surface chemical activity of MXene has been greatly improved,which has great advantages in compounding with polymers,simplifies the experimental process,and broadens the application range of conductive filler and has outstanding contributions in electromagnetic shielding and mechanical enhancement.The main works of this parper are as follows:(1)Based on natural rubber,complete segregate networks are constructed to prepara stretchable and electrical conductive nanocomposite films,and their mechanical,electromagnetic shielding properties are researched:an efficient vacuum-assisted filtration approach for the fabrication of flexible and highly conductive Ti3C2Tx MXene/natural rubber(NR)nanocomposite films by constructing interconnected MXene networks in NR matrix.Finally,the nanocomposite achieves a conductivity of 1400 S m-1 and an electromagnetic shielding performance of 53.6 dB at 6.71 vol%fillers,which has great advantages in stretchable conductive nanocomposites.(2)The thermosensitive poly(N-isopropylacrylamide)(PNIPAM)was combined with MXene to prepare a double-layer MXene/PNIPAM composite hydrogel and be carried out its thermally responsive performance study:by directly growing a layer of MXene/PNIPAM composite hydrogel on the surface of a layer of pure PNIPAM hydrogel,the characteristics of the two components are fully utilized to form an active layer and an inert layer,so that the deformation under temperature stimulation of the MXene-containing side is smaller than that of the MXene-free.Then we prepared a composite hydrogel bended to one side.At the same time,the introduction of MXene brought hydrogen bonding interactions,and simultaneously improved the tensile strength and elongation at break of the hydrogel,which greatly helped the application of the hydrogel in the actuator and sensor.