Preparation Of Graphene/polystyrene Microspheres And Its Foaming And Adsorption Properties

In this thesis,graphene oxide(GO)was prepared by Tour method under the strong oxidation of concentrated sulfuric acid and phosphoric acid.Then the graphene oxide/polystyrene(PSG)microspheres were prepared by suspension polymerization,in which water was introduced into PSG microspheres through GO and water could play the role of foaming agent by microwave foaming process.The structure and properties of GO and composite microspheres were characterized by means of scanning electron microscopy,Fourier transform infrared spectrometer,X-ray photoelectron spectroscopy,Raman spectroscopy and thermo-gravimetric analysis.The influence factors for preparing PSG microspheres were studied,and the effects of particle size,GO content and foaming time on the microwave foaming ratio were discussed.The results showed that GO(few layer graphene oxide)with high oxidation degree,less than 10 layers and40.4%water content was prepared;the optimal conditions for preparing PSG microspheres were as follows:2.5?3 water/oil ratio,2%?2.5%TCP-PVA composite dispersant,450?500 r·min^-1 stirring rate and GO content of 3%;the microsphere surface of the foamed particles was with porous structure;the particle diameter,GO content and foaming time had significant influence on the foaming ratio;the average foaming ratio was about 2.5 times;the adsorption capacity of the foamed PSG microspheres to soybean oil could be up to 435%;the adsorption process of microspheres to soybean oil was accorded with the pseudo-second-order kinetic adsorption model.The microwave foaming process with water as foaming agent is proved to be feasible,and PSG composite microspheres are expected to be widely used in the field of oily domestic wastewater and heavy oil wastewater treatment.