Functionalization Of Graphene Oxide And The Preparation Of Graphene Oxide/epoxy Nanocomposites

Graphene oxide has unparalleled mechanical properties,electronic effects,optical properties,thermal properties,etc.,and has a wide application space.At the same time,through the organic combination with the traditional polymer materials,synergistic effect can be achieved,which can give the composite materials better mechanical and radiation resistance.However,due to the compatibility problem,graphene oxide has encountered a large bottleneck in improving the mechanical properties and conduction properties of composite materials.Therefore,how to make graphene oxide maximize its excellent performance and achieve structure-function integration is the focus of current researchers.In this thesis,conducting surface modification on graphene oxide sheet.Then,the modified graphene oxide and the general polymer material epoxy resin are used for organic compounding,the effects of various factors on the microstructure and mechanical properties of modified graphene oxide and composites were studied in detail,and the surface modification mechanism was explored,the specific research results are as follows.Firstly,the surface polymerization method was used to initiate polymerization of styrene monomer on the surface to realize the surface organicization of graphene oxide,and at the same time,GO-polystyrene hybrid material(GO@PS)was prepared.The microstructure,preparation mechanism,thermal properties and dielectric properties of the hybrid materials were investigated.The results show that when graphene oxide is 1.32wt%,the grafting rate of PS in GO@PS product is the highest,reaching 95wt%,and the Tg is also the highest at 190.53?.When graphene oxide is 1.65wt%,the GO@PS product is the thermal stability is the best,the thermal decomposition temperature reaches 320?;When graphene oxide is 1.32wt%,the GO@PS dielectric constant ?r can be up to 248.Secondly,based on the previous work,the activated graphene oxide was further modified by two-dimensional(2D)organic titanium nanomaterials,and the GO-organic titanium solid structure(GO@Ti)was constructed.The surface modification reaction mechanism was explored,and the action law of the reaction environment on the microstructure of the product was summarized.Finally,in order to further reflect the structure-function integration of the materials,the above-mentioned GO@PS,GO@Ti and epoxy resin were combined to prepare modified composite materials GO@PS/epoxy and GO@Ti/epoxy.The action law of reaction elements on the tensile properties and microstructure of the composites was investigated.Through the tensile stress-strain experiment of the composite material,it is proved that when GO@Ti/epoxy is 6wt%,the maximum elongation at break and toughness of the composites are 6.06%and 2.53 MJ/m3,respectively,compared with pure epoxy resin(3.24%,1.23 MJ/m3),it increased by 87%and 106%,respectively.When GO@PS/epoxy is 8wt%,the elastic modulus and tensile strength reached a maximum of 1.97 and 78.97Mpa,respectively,compared with pure epoxy resin(1.69,47.17 MPa),it increased by 16.6%and 67.4%,respectively.In summary,the surface modification of graphene oxide by different means can change the compatibility in the composite material,and the composite material exhibits superior performance due to synergistic effect.This research will have important research significance and application value for the application of graphene oxide materials.