Qualitative Detection Method Of Graphene Materials In Fibers

Since the discovery of graphene,the excellent properties of graphene have aroused great interest in graphene research.The combination of graphene material and fiber can increase the fiber strength and Young’s modulus,and also enable the fabric or fiber to obtain special functions such as electric conduction,ultraviolet protection,far infrared,antibacterial and the like.With the improvement of people’s living standards,functional clothing containing graphene materials has increasingly attracted consumers’ attention,but the quality of the products varies,this kind of phenomenon is disrupting the market order and has attracted the high attention of relevant institution.In order to better protect the legitimate rights and interests of consumers,also in order to promote the healthy development of the functional textile market for graphene materials in China,it is urgent to develop corresponding testing methods to maintain market order.In this paper,the qualitative detection method of graphene materials in fibers is deeply studied.Finally,the qualitative detection method of graphene materials in fibers is established,and the tentative explortion of quantitative detection method of graphene materials in fibers is explored.conclusion as below:(1)Qualitative detection of graphene materials in fibers: three different matrices fiber(polyester fiber,polyamide fiber and viscose fiber)were identified by using scanning electron microscopy(SEM),atomic force microscopy(AFM),Raman spectroscopy(Raman)and field emission transmission electron microscopy combined with energy spectroscopy(HRTEM-EDS)The results showed that only HRTEM-EDS could obtain better detection results.The HRTEM-EDS detection method includes two means of implementation: separation detection and in situ detection.The former is to dissolve the fiber body with solvent,and then a part of the particulate matter in the sample is extracted by centrifugal separation.In the latter,the aggregate in the fiber is exposed to the cuntting surface of the sample by mechanical cutting.After that,the content of C element in the aggregate was tested by EDS,and the number of layers was then observed from the edge of the aggregate by HRTEM.In this way,the aggregate was qualitativelyanalyzed,and the graphene material was determined according to the content of the graphene material in aggregate.The mass percentage of C element in the aggregate micro-region is ≥60%,and the number of edge layers of the aggregate should be ≤ 10 layers,only if both of these conditions are met,we can call it graphene materials.In addition,the study found that most of the fiber additives are a mixture of graphene material and graphite.The criterion of quantitative method is as follows: 10 aggregates of particulate matter are randomly selected and not less than60% of the aggregates contain graphene materials,the P value is ≥60%,we can conclude that the fibers contain graphene meterials.The qualitative detection method of graphene material in fiber established in this paper has the characteristics of simplicity and quickness,and can directly and accurately identify the particulate matter in the fiber.The establishment of this test method fills the technical gap of the testing organization in this field.(2)Tentaive quantitative detection of graphene materials in fibers: dissolvingcentrifugal-filter membrane interception-element analysis method to quantify graphene materials in nylon fibers.The strong acid dissolution and microwave digestion of the fiber containing graphene material were studied.It was found that microwave digestion can decompose the oxidized graphene material,but can not decompose non-oxidized graphene.Therefore,the strong acid dissolution method is more suitable for the membrane retention method.The main steps of the membrane retention method: fiber dissolution centrifugal-aggregation-filtration-weighingfiltration-element analysis.However,the final result is very inaccurate,and the graphene material will form a tighter film on the surface of the filter to hinder the filtration.Therefore,the quantitative method needs further investigation.