Preparation And Application Of Silk Fibroin/Graphene Composite Film

In this paper,the silk fibroin/graphene conductive film was prepared.Firstly,a Graphene/PVA dispersion was prepared,and then mixed with silk fibroin solution to obtain a stable Silk Fibroin/Graphene/PVA dispersion.Then,Silk Fibroin/Graphene composite film was obtained on a polydimethylsiloxane(PDMS)template by a casting method.Our goal is to prepare a composite material with good electrical conductivity,mechanical properties and biocompatibility,which is expected to be applied in the field of human body sensing and wearable sensing.Firstly,a low molecular weight of PVA was used as a dispersant and prepared a well-dispersed Graphene/PVA aqueous dispersion.Then mixed with silk fibroin solution to obtain a stable Silk Fibroin(SF)/Graphene/PVA suspension.The SF/GR film was obtained by the casting method.It was proved that this material has a ’brick-mud’ structure which is characterized by scanning electron microscopy(SEM),infrared spectroscopy(FTIR),and X-ray diffraction(XRD).The mechanical properties,electrical properties,and dissolution rate of the film were tested respectively by universal material testing machine,four-probe resistance meter and UV spectrophotometer.The results show that the SF/GR composite film has good electrical and mechanical properties,when SF/Graphene=10:1,PVA/Graphene=1:4.The introduction of certain amount of butanediol can significantly reduce the dissolution rate of the film,improve the mechanical properties,and increase the application range.Furthermore,the effect of adding glycols in different proportions on film’s structure and performance were investigated.The results show that the addition of glycol can promote the formation of regular secondary structure of silk fibroin.The effect of hexanediol on silk fibroin protein was stronger than that of butanediol and ethylene glycolwith a same content.The addition of diols in different proportions had a similar impact on the conductive properties of SF/GR composite films,and the trend was to decrease first and then increase.The lowest sheet resistance was 380±80Ω.In addition,the addition of glycols in different proportions could greatly reduce the dissolution rate of the film,expand the performance range of the film,and broaden the potential application area of the composite film in the future.Based on the first two chapters,various sensitive properties of SF/GR composite films were tested.It was found that the composite film had good force-sensitivity,humidity-sensitivity and memory properties,which proved its potential value in the field of human body sensing and wearable sensing.