Application Of Polystyrene/Graphene Composite Microspheres In Functional Materials

In this paper,based on the preparation of polystyrene/graphene composite microspheres by heterogeneous coacervation method,by regulating the distribution of graphene oxide on the surface and medium of composite microspheres,it is applied to the preparation of highly conductive nanocomposites and highly sensitive and wide working range flexible strain sensors.A brief introduction of the work is as follows: 1.Preparation of polystyrene/graphene composites with highly ordered three-dimensional network structure and study of their electrical conductivityPolymer/graphene conductive composites have attracted the attention of researchers due to their huge application potential in many fields such as coatings,batteries,and sensing.However,the agglomeration of graphene in the polymer matrix cannot be avoided by conventional processing methods in the preparation of composite materials,and the ability to control the dispersion state of graphene is limited,which makes it difficult to effectively improve the conductivity of the materials at lower graphene content.In order to more effectively control the structure of the composite material and obtain better performance,based on the particle construction method previously proposed by this research group,we have proposed a simple and practical method of combining heterogeneous aggregation with suction filtration and casting.That is,according to the existence of a certain distribution of graphene oxide(GO)on the surface of the composite microspheres and the medium during the heterogeneous agglomeration process,the free state of GO nanosheets can be deposited between the composite microspheres through the adjustment of related parameters and the use of suction filtration,Then through subsequent reduction and compression heat treatment,a binary structure composite material with a graphene three-dimensional network and two-dimensional orientation is prepared.The composite has a high electrical conductivity of 1344.3 S/m when the r GO content is only 2.10 vol%.In this paper,we discuss in detail the effects of particle size,graphene content,preparation method,and filtration conditions on the structure and electrical properties of composite materials.The results show that the structure of the composite material is orderly and controllable to a certain extent,and there is a clear correlation between the structure and electrical properties.2.Preparation and performance study of high performance flexible sensor with polystyrene/graphene conductive microsphere array structureIn the past ten years,stretchable strain sensors have received wide attention due to their huge application potential,but obtaining sensing materials with both high sensitivity and wide operating range remains a challenge.To this end,we use the conductive properties of polystyrene/graphene composite microspheres to design a binary structure composed of microsphere arrays and graphene nanosheets mixed with them.This unique binary structure can generate a certain bridging effect,thereby improving the sensitivity of the sensor(GF=481)and widening its working range(maximum sensing strain is 104.5%),effectively solving the above-mentioned key problems.In addition,the structure has good stability.After 3000 cycles of stretching,there is no significant change in sensing performance.Moreover,we introduced one-dimensional carbon oxide nanotubes or silver nanowires on the basis of the binary structure to form a multiple structure combining one-dimensional,two-dimensional,and three-dimensional to further enhance the split-bridge effect,thereby making the sensitivity of the sensor and the working range has been improved again(GF=1171,the maximum sensing strain is 134.4%).Studies have proved that the sensor has a simple,regular and controllable structure,and has significant application prospects in human motion detection and object quality detection.