| With the rapid development of microelectronics technology,new electronic devices are also shifting towards miniaturization,integration,and intelligence.However,the current electronic devices have a limited macrostructure and are mostly made of traditional rigid electronic materials,which not only do not conform with ergonomic principles but also causes the problem of electronic functions decline.In order to improve the integration of electronic devices and the human body,emerging electronic textile materials combine the inherent properties of textile substrates?such as lightweight,softness,breathability,comfort,and durability?and the unique functions of microelectronic materials?such as electrical conductivity,dielectric,and sensing,etc.?to balance the wearability and electronic functions of wearable devices.Nevertheless,the functionality and durability of the current electronic textile materials cannot be effectively unified and is mainly manifested in:1)the size and material of the micro electronic materials are different from the textile substrate,and the existing preparation process cannot be effective integrated the advantages of them;2)the flexible electronic device based on the composite between the electronic functional layer and the textile substrate has the problem of Young's modulus mismatch,which is prone to fracture or even interface separation during long-term using;3)sensitive fiber materials prepared by structural integration are susceptible to environmental factors due to its physical morphology or chemical structure defect,resulting in the functional stability of electronic fabrics decreased.Herein,on the basis of the flexibility strategy of rigid electronic materials,and with the help of screen printing,electrospinning,micro-structure topography construction,as well as surface chemical structure modification,electronic fabric materials were fabricated to retain and improve the wearability as well as electrical conductivity,pressure sensing,and electrochemical sensing function,thus realizing the cross-scale manufacturing of structures,devices,and systems of different sizes/materials,and lay a research foundation for the future development of the wearable industry.The main contents are:Based on the destabilization mechanism of silver nanoparticles?Ag NPs?and the screen-printing process,Ag NPs-based conductive inks that can be sintered at low temperature and flexible printed circuits with lower resistivity were prepared.Spherical Ag NPs?10nm?are used as conductive filler;alcohol co-solvent is used as a dispersant;in addition,polyaniline?PANI?and dilute hydrochloric acid?HCl?are used as additives and chemical sintering agent.The mechanism of chloride ion?Cl-?destabilization and sintering regulation for Ag NPs was studied;in addition,the internal correlation between the concentration of PANI and the application performance of flexible printed circuits was explored.The results show that there is a strong interaction between Cl-and the surface of Ag NPs;during the drying process of the printed circuit,the concentration of Cl-increases and replaces the original stable groups on the surface of Ag NPs,which exposes the surface area of Ag NPs and generates spontaneously gather;then undergo the Oswald ripening process and continue to grow into a bulk sintered morphology,so that the printed circuit shows excellent conductive function after low-temperature treatment.In addition,with the introduction of PANI in the conductive ink,the solid content and viscosity of the conductive ink also increase,and the clarity and conductivity of the printed circuit are improved.When the solid content of Ag NPs in the conductive ink is 30 wt.%,the content of PANI is 27.8 wt.%and the initial concentration of HCl is50 m M,the printed fabric circuit can be sintered at 60?and exhibited good conductive properties(The resistivity is 2×10-5?·m).Finally,a fabricated flexible printed circuit was used to replace the traditional rigid circuit mode and light up the parallel LEDs.The development of low-temperature sintered conductive ink can effectively avoid the traditional high-temperature sintering process and provides an effective strategy for broadening the application of heat-sensitive substrates in printed electronics.By introducing a polymer elastomer as the binder phase of conductive ink,the stability of the conductivity of printed conductive fabrics under repeated bending or compression has been improved;in addition,based on the idea of polymer swelling and spontaneous sintering of Ag NPs,the post-processing process of co-solvent?chemical sintering agent and swelling agent?was prepared and a printed electronic fabric with micro-scale conductive wrinkle structure was generated.Among that,due to the large difference in elastic modulus between the swollen WPU molecule?soft material?and Ag NPs sintered morphology?hard material?,compressive stress will be generated at the interface of the soft/hard material,and then the internal stress release process forced the WPU to form a micro-scale fold structure in the composite system during the solvent drying process.In particular,when the solid content of Ag NPs is 50 wt.%,and the dried printed pattern is treated with a co-solvent?polycationic quaternary ammonium salt?DADMAC?,ethanol and dichloromethane?DCM?were 10:5:10 according to the volume ratio,respectively?at room temperature,a printed pattern with a resistivity of 0.01?·m can obtain Benefiting from the micro-fold structure inside the conductive polyester fabric,the two conductive fabrics were assembled face-to-face and a pressure-sensing fabric with good response to tiny pressure?29 Pa?was obtained.After more than 160 cycles of bending and compression,the pressure-sensing fabric has good conductivity stability,faster response time?63 ms?and good consistency;it realizes synchronous monitoring of the frequency and intensity of human motion signals and maintain good functional stability under mechanical external force,which provides a research basis for the realization of wearable electronic fabrics.Based on the capacitive pressure sensing mechanism and the impact of the actual atmospheric environment on the dielectric material,a wearable full fabric pressure sensor with stable chemical structure and physical morphology,low moisture absorption,and anti-interference of the output signal is constructed.By theoretic analysis and designing the structure of poly?ionic liquid??PIL?,poly?1-vinyl-3-butylimidazole bistrifluoromethanesulfonimide?with strong polarity?the dipole moment of the repeating unit is 12.49 Debye?and stable chemical structure was prepared and used as the main component for the fabrication of dielectric materials.Then,the poly ionic liquid nanofiber?PILNM?with a diameter of 213 nm and[PBVIm][TFSI]content up to 67 wt.%was prepared by electrospinning.Using PILNM as the dielectric layer and assembling with conductive polyester fabric according to the"sandwich structure",an all-textile flexible parallel-plate capacitor with an initial capacitance value of 45 p F?0.5 MHz?was obtained.The PILNM-based flexible capacitors were further packaged in cotton fabrics,and it can show the synchronous response to human physiological signals?including pulse vibration,throat tremor,thoracic contractions,finger movements,and elbow bending,etc.?was developed.Based on the advantages of PILNM's three-dimensional porous structure and high polarizability,the full fabric pressure sensor has a high sensitivity to small pressures?sensitivity in the range of 0.2 k Pa can reach 0.49 k Pa-1?and faster response time?30 ms?.In addition,due to the chemical structural stability and hydrophobicity of the dielectric PILNM,the pressure sensing fabric can maintain a good sensing stability and consistency under different humidity environments?70%RH?and after multiple items of washing?more than 10 times?.The preparation and design of PIL dielectric materials provide new ideas for the construction and use of new polymer dielectric materials and immune environment interference pressure sensors.In addition to improving pressure sensing performance,PILNM can also be designed as flexible electrochemical sensing nanofiber membranes and then modified on the surface of traditional electrodes to improve the performance of single-component nanofiber membrane modified electrodes.The hybrid nanofiber membrane with[PBVIm][TFSI]content of 50 wt.%?50%PILNM?was selected and went through the surface chemical modification process to functionalize amino group on the surface of PILNM.Due to aminated PILNM has a porous structure,a large specific surface area,a bipolar ionic liquid molecular chain skeleton,and high reactivity,it can be used for the efficient capture of formaldehyde?HCHO?molecules;meanwhile,it can also promote the ions transport in the micropores of the PILNM modified electrode,thereby significantly improving the ion storage and ion conductivity of the single-component nanofiber membrane modified electrode,thus enhancing its electrochemical signal strength.Finally,The results showed that the surface water contact angle of HCHO-reacted amino-functionalized PILNM changed from the original of 32°to 46°,and the Zeta potential of it also changed from the original of 96 m V to 81m V;also,the current signal of the modified electrode in the electrolyte solution was also significantly enhanced.When the concentration of the HCHO solution is ranging from 3.6×10-8 to3.6×102 mg/L,there is a linear correlation between the peak current change rate of the PILNM modified electrode and the concentration of HCHO?R2=0.93?.In addition,the PILNM modified electrode also showed a good detection performance on trace HCHO in domestic drinking water.By directing and efficiently designing the surface chemical structure of PILNM,a modified electrode for chemical molecular sensing can be constructed,which provides a new way for the design of new highly sensitive chemical sensors. 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