| With the development of advanced composite materials towards nanometer,multifunction and cutting-edge,it is urgent to develop high-performance nano-composite materials with integrated structure and function,so as to promote the upgrading of high-tech in the national and military fields.Layered structure is an important design strategy to improve and optimize the properties of nanocomposites because of its diverse interface characteristics and singular confinement effect.Through structural assembly design,selecting proper nano-functional units and introducing component control with interface matching,nano-composites can be endowed with special functional characteristics and good mechanical properties,and layered nano-composites with integrated structure and function can be obtained.However,at present,the single structu ral design mode,inefficient peeling and dispersing technology and limited interface control means limit its performance improvement and engineering practicability.Starting from the structural design,this paper takes one-dimensional/two-dimensional nanomaterials as structural functional units,and bionic designs inorganic sheet/polymer uniform laminate,inorganic sheet/fiber interconnection laminate,and inorganic sheet/nanotube asymmetric laminate,and obtains a series of high-performance layered nanocomposites with integrated structure and function.This paper enriches the design mode of layered structure,solves the problem of efficient peeling and dispersion of functional units,improves the interface interaction of layered nanocomposites,and realizes the high-performance preparation and continuous production of layered nanocomposites with integrated structure and function.The specific research contents and results are as follows:（1）Uniform laminated structure of inorganic sheets/adhesives was desig ned,and vermiculite nano sheets（VMTs）/sodium alginate（SA）composite membrane with integrated structure and heat protection was developed.By plane stretching the aqueous VMTs/SA network with hydrogen bonds and ionic bonds,the spatial conformation of VMTs in VMTs/SA network was regulated,and a highly oriented uniform laminated structure with synergistic interfacial adhesion was realized,thus strengthening its mechanical properties.The tensile strength reached 429.0 M Pa and the modulus was 43.8 GPa,which was superior to most reported clay-based nanocomposites.In addition,VMTs with high filling content（～70%）is evenly distributed in the laminated structure,which endows VMTs/SA composite film with good thermal insulation and flame-retardant properties.（2）The inorganic sheet/fiber interconnection laminated structure was further designed,and the boron nitride nanosheet（BNNSs）/aramid nanofiber（ANF）composite membrane with integrated structure and heat conduction was developed.Firstly,the high quality,high yield and high concentration of BNNSs were prepared by the established paste-based sanding stripping method.Then,ANF is used as the interconnection network framework,and the interconnection laminated structure is bionic constructed by using the anti-charge ion induced assembly method.At last,based on the anti-charge ion induced assembly method,a continuous film-making process of sol extrusion-gel conversion-rolling orientation was developed,and BNNSs/ANF composite film with excellent mechan ical properties（156.0 MPa）and thermal conductivity(31.1 W m-1 K-1)was prepared in a large area,which provided a research foundation for the industrial production of high-performance structural thermal conductivity integrated layered nanocomposites.（3）Furthermore,the orientation of the nanofibers in the interconnected laminated structure is regulated,and the mica nano sheets（c NTS）/ANF composite film with integrated ultraviolet shielding structure is developed.The oriented arrangement of nanofibers significantly improved the mechanical properties of the composite film,showing excellent tensile strength（496.6 MPa）and high toughness(13.6 MJ m-3).At the same time,the composite film also has good bending resistance,and its tensile property still has a retention rate of 85%after repeated folding for 100 times.In addition,the high-strength composite film has good transparency and oxygen barrier property,and the oxygen transmission rate is one order of magnitude lower than that of commercial PET packaging film.More importantly,the composite film also shows excellent ultraviolet shielding performance,which can shield more than 99.85%of ultraviolet rays,and has great application potential in the field of advanced packaging.（4）Finally,based on the research foundation of uniform laminated structure and interconnected laminated structure,the asymmetric laminated structure of inorganic sheet/nanotube is designed,and the graphene oxide（GO）/carbon nanotube（CNT）film actuator with integrated structure intelligent response is developed.Using the hydrophilic difference between GO and CNT,excellent photothermal conversion efficiency and mechanical anisotropy,the response of the actuator to humidity and near infrared light is ultra-fast（0.08 s）,reversible（10,000 cycles）,large amplitude(70°mm-1)and directionally controllable deformation（directional bending and torsional）.According to the stress mismatch principle of asymmetric laminated structure,the response mechanism of GO/CNT thin film actuator is systematically expounded.In addition,through the physical demonstration,it is revealed that the actuator can easily complete a series of complex and controllable mechanical movements under the stimulus response.For example,jump vertically at a speed of 250 mm s-1,roll horizontally at a speed of 12 mm s-1,throw objects at a speed of 505 mm s-1,instantly capture flying objects at a speed of 335 mm s-1,and lift objects weighing 23 times in 0.34 seconds.This kind of intelligent actuator with ultra-fast,large amplitude and controllable deformation is expected to be used in the fields of artificial muscles,bionic devices and small robots. |
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