Preparation And Properties Of Carbon Nanocoatings Based On Polymer Co-Pyrolysis Of Glass Fibre

Carbon nanomaterials have become popular materials in chip manufacture,aerospace,energy storage,biomedicine and other fields.And glass fibre is a kind of inorganic nonmetallic reinforcing material which is widely used in automobile,electric appliance and other industries.With the development of conductive coatings on the surface of materials,the traditional metal coatings applied to conductive glass fibres have some disadvantages such as poor corrosion resistance,poor interface bonding performance and expensive preparation.Therefore,this paper uses polymer as carbon source to prepare conductive carbon nanocoated glass fibres from the perspective of conductive performance of glass fibres.The carbon nanocoating on glass fibre was prepared by chemical vapor deposition through polymer pyrolysis.The microstructure and properties of the carbon nanocoating prepared by individual carbon source and co-pyrolytic carbon source were analyzed by SEM,Raman,XPS,four-angle probe resistance test and other instruments.At the same time,the process of polymer pyrolysis,coating deposition and the interaction mechanism of substrate interface were investigated and analyzed by molecular dynamics.The details are as follows:（1）Carbon nanocoating on glass fibre was successfully prepared by single carbon source polypropylene（PP）.And the growth of carbon nanocoating under different preparation temperatures was investigated and the morphology and properties of the prepared carbon nanocoating were characterized.The carbon nanocoating is a kind of sp²hybrid multilayer graphene-like structure with certain defects.（2）Taking PP as an example,molecular dynamics simulation was used to explore the pyrolysis reaction process,the deposition and growth process of carbon structure on SiO₂substrate surface.Polypropylene was gradually pyrolyzed to form carbon-containing small molecules in the simulation system.Graphene-like nucleation sites were formed on the surface of the substrate during the reaction.The carbon-containing small molecules underwent dehydrogenation,recombination and ring growth,and carbon nanocoating was deposited on the surface of the substrate during the reaction.（3）Carbon nanocoating on glass fibre was successfully prepared with polyethylene terephthalate（PET）and polyvinyl chloride（PVC）as single carbon sources.The microscopic morphology and properties of carbon nanocoating was characterized.The carbon nanocoating prepared by PET or PVC is sp²hybrid multilayer graphene-like structure with certain defects and the latter has fewer defects.（4）Using polypropylene and polyvinyl chloride（PP&PVC）as co-pyrolytic carbon source,the microstructure and properties of carbon nanocoating with PP:PVC ratio of 3:1,1:1 and 1:3 were investigated.It could be found that there were small cracks on the surface,the defects increased and the electrical conductivity of the fibre decreased.When the ratio of co-pyrolysis carbon source was 1:1,the carbon nanocoating had relatively fewer defects and better electrical conductivity.