▎ 摘　　要

NOVELTY - The flexible resistance-type pressure sensor based on carbonization electrostatic spinning fibre has a pressure-sensitive film (2) and upper flexible electrode (1) and lower flexible electrode (3) respectively attached to the upper and lower surfaces of the pressure-sensitive film. The pressure-sensitive film takes a carbon nanofiber structure obtained by carbonizing a polymer electrostatic spinning film under nitrogen atmosphere at 700-900 ℃ as a conductive framework. The fibrous one-dimensional nano material is filled between the carbon nanofibers in a dip-coating mode to form a composite flexible film. The whose device is packed and fixed, after ensuring the stable contact between the electrodes and the sensitive film. The upper flexible electrode and the lower flexible electrode are respectively provided with a bonding lead at one side for measuring external working voltage and output signals. USE - Flexible resistance-type pressure sensor based on carbonization electrostatic spinning fibre. ADVANTAGE - Compared with nano carbon materials such as graphene, the conductive carbon framework retains the unique three-dimensional network characteristics of the electrospinning process, has better stress transfer characteristics, and has adjustable conductivity along with the carbonization process. The filling of the bacterial cellulose improves the flexibility and the recovery performance of the film, and the bacterial cellulose is inserted between the carbon fibers, so that the variable conductive path number in the film is further increased. The sensor fully utilizes the piezoresistive performance advantage of the carbon nanofiber framework, and has easy preparation and low cost. The prepared sensor has high sensitivity and wide detection range. The device has low manufacturing cost, batch production, light weight and no biological harm, and can be attached to the skin of a human body for real-time physiological health signal detection. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a method for preparing the flexible resistance-type pressure sensor based on carbonized electrostatic spinning fibre, which involves: cutting a flexible substrate layer film with the length and width of 2-3 cm and the thickness of 100-300 µm, ultrasonically cleaning the flexible substrate layer film with ultrapure water and absolute ethanol, and drying the flexible substrate layer film; printing a layer of rectangular silver electrode on a flexible substrate layer film using conductive silver paste through a screen printing technology, and bonding a lead wire on one side of the electrode using the silver paste after drying to serve as an upper flexible electrode and a lower flexible electrode; weighing 1-1.2 g polyacrylonitrile powder, dissolving the polyacrylonitrile powder in 8.8-9 g N,N-dimethylformamide solution, magnetically stirring for 8-12 hours under the condition of 35-50 ℃ water bath, and preparing a spinning 10-12 wt.% precursor solution; putting the spinning precursor solution into an injector, setting electrostatic spinning voltage to be 18-20 kV, setting the distance between a needle point collector and a syringe to be 12-15 cm, setting the pushing speed of a pushing pump to be 8-12 μl/minute, setting the ambient temperature to be 40-50 ℃, receiving spinning fibers through aluminum foil, and spinning for 2-4 hours to obtain a spinning film which is white in macroscopic appearance; drying the obtained film in a drying oven for a period of time to fully volatilize the residual organic solvent; taking out the spinning film from the aluminum foil and clamping by two titanium nets, and introducing into a tube furnace for heat treatment and raising the temperature to 230-280 ℃ in the air atmosphere, and keeping for 1-3 hours for pre-oxidation to obtain a brown yellow film on the surface; continuously introducing nitrogen as a protective gas after the pre-oxidation stage is finished, then keeping the heating rate of 2-3 ℃/minute, slowly heating to 700-900 ℃, carbonizing for 2-3 hours, and then cooling along with a furnace to obtain a pure black carbon fiber film; preparing 0.3-0.5 wt.% bacterial cellulose aqueous dispersion, soaking the carbon fiber film in the aqueous dispersion for 30-60 minutes, taking out the carbon fiber film, repeatedly soaking for 2-3 times, and placing the film on a heating table at 40-50 ℃ to dry excessive moisture to obtain a pressure-sensitive film; and tightly attaching the obtained pressure-sensitive film to the printing silver electrode, and sealing and fixing by using an adhesive tape. DESCRIPTION OF DRAWING(S) - The drawing shows a schematic structural diagram of the pressure sensor. 1Upper electrode 2Pressure-sensitive film 3Lower electrode