The Preparation And Performance Research Of The Polymer/Functional Graphene Composites

As a new generation of carbon allotropes following the carbon nanotubes,the graphene has excellent thermal stablity,chemical stability,electron transport capacity,the Holzer effect under normal temperature and large specific surface,which attracts more and more attention from researchers. As a kind of excellent functional materials,the graphene and its derivatives have been widely used to prepare various nanocomposites in the field of polymer composites,and graphene based materials have shown promising applications in magnetics, optics,catalysis,energy storage etc.However,preparation of graphene based materials and the homogeneous incorporation of graphene into polymer matrix are still challenges which needs to be solved in both industry and academia. With the aim of settling these problems,this graduation thesis hammer at the preparation of functional graphene by adopting some neoteric methods,and has successfully synthesized a series of high-performance polyer composites/functional graphene composite materials,and then has characterized some properties.The main contents are as follows:1. The surface modification of graphene oxide. At first,to make the semi-enclosed toluene diisocyanate (b-TDI) by methyl ethyl ketone oxime (MEKO) and toluene diisocyanate (TDI) were reacted in a molar of1:1,then, graphene oxide was surface grafting treated in N,N-dimethyformamide in use of the b-TDI to obtain functionalized graphene oxide. The functional graphene oxide has a good disperation in both water and organic solvent.2. The preparation of graphene. Hydrazine hydrate which has strong reducibility was used to reduce the hydroxyl and epoxy group which were on the surface o f the graphene and the carboxyl and carbonyl on the edge of the graphene oxide, and finally obtained the functionalized graphene(bi-G) whose surface contained bl ocked isocyanate groups.3. The preparation of waterborne polyurethane/functionalized graphene composit e materials.Firstly,the waterborne polyurethane dispersions were synthesized using the prepolymerization process,with polybutylene adipate(PBA), isophorone diisocya nate(IPDI),dimethylolpropionic acid(DMPA) as hydrophilic monomer. Secondly,the different mass fraction of the bi-G was joined into the waterborne polyurethane a nd WPU-GNS nanocoposite emulsion was prepared by water high shear dispersio n after joining triethylamine. The dispersion had a good dispersion stability,using a transmission electron microscope(TEM) observition of the dispersion liquid wa s found to be coated with graphene and uniformly dispersed in the aqueous poly urethane micelles.Meanwhile,Thermal gravimetric analyzer (TG) was used to char acterize the thermal stability,and the TG analysis showed that the composite’s the rmal stability has significantly improved, especially after heat treatment,the polyu erthane/graphene composite’s heat perforesmance is more prominent.4. The preparation of the epoxy resin/functionalized graphene composite materia Is.The bi-G as dispersion phase was mixed with the epoxy to obtain the epoxy r esin/graphene nanocomposites.And the nanocomposites were characterized by TE M,TG to research the impact of graphene in improving the function of the epox y resin.The results showed that the graphene had a good dispersion in epoxy res in,and the thermal stablity of the nanocomposite was also improved.