| Mesoporous carbons exhibit great specific surface area and pore volume,good thermal stability and chemical inertness and so on,and have been extensively used in many application areas,such as the separation and purification processes,catalytic support, double layer super capacitors and so on.However,traditional porous carbons mainly contain micro-pores,and the volume capacity of meso-pores is low and the pore size distribution is wide.In this thesis,acrylonitrile-methyl methacrylate(AN-MMA) copolymer/nanometer silica composite particles were synthesized by in-situ emulsion polymerization,then carbonized and etched with HF to obtain the mesoporous carbon materials.The absorption of 2,2'-azobis(2-amidinopropane)dinydrochloride(AIBA) onto nano-SiO2 particles,the kinetics of in-situ emulsion copolymerization of AN-MMA in the presence of nano-SiO2 absorbed with AIBA,the size distribution and morphology of the composite latex,and the formation mechanism of the composite particles were investigated. Furthermore,the influences of the content of nano-SiO2 in the composite particles and cabonization temperature on the pore size and its distribution,specific surface areas,and morphology of mesoporous carbons and the formation mechanism of mesoporous carbons were studied.Finally,the mesoporous carbons with many meso-pores and narrow pore size distributions were prepared.The aqueous dispersion of nano-SiO2 particles with size of 10～15nm were used to prepare AN-MMA copolymer/nanometer silica composite particles in the presence of silica absorbed with AIBA by electrostatic action.AIBA initiator could be effectively adsorbed onto the surface of nano-SiO2 particles when the pH value of the dispersion medium was greater than the isoelectric potential point of SiO2.It was found that when the pH value of the dispersion medium was adjusted to 11,Zeta potential of SiO2 reached a maximum value.The dispersion stability of silica particles was decreased as the amount of added AIBA increased.There existed an upper limit of stable electrostatic adsorption of AIBA onto silica.When pH=11,the upper critical absorption of AIBA was 0.24 mmol·(g·SiO2)-1.In-situ emulsion copolymerization of AN-MMA was initiated by AIBA adsorbed onto the surface of nano-SiO2 particles.It was found that the rate of copolymerization was increased as the amount of AIBA and temperature increased,and was decreased as the concentration of nano-SiO2 increased.The volume average size of composite particles was increased as the concentration of nano-SiO2 increased.When the concentration of Tween-80 was kept at 2.0g/L,the size distribution of composite particles was narrow and the volume average size was 450nm.Adding of sodium lauryl sulfate at the middle or final stage of polymerization could remarkably increase the stability of the composite latex.The combination condition of AN-MMA copolymer latex particles with SiO2 particles was characterized by the centrifugation/redispersion,thermal treatment in the muffle furnace.It was found that more than 85%silica particles were completely encapsulated in AN-MMA copolymer after several cycles of centrifugation/re-dispersion when the mass ratio of SiO2 to AN-MMA was 10%and 20%.N,N-dimethylformarnide extraction of the composite particles showed that a part of copolymer was grafted onto silica.The grafting efficiency of AN-MMA copolymer on silica particles was increased as the concentration of nano-SiO2 increased.The morphology of the AN-MMA copolymer/nano-SiO2 composite latex particles was observed by using transmission electron microscope(TEM).It was found that the obtained AN-MMA copolymer/silica composite particles obviously exhibited rough surfaces and nanometer silica particles were well combined with latex particles when the concentration of silica was less than 30%.When the concentration of SiO2 was greater than 30%,a part of silica particles were separated from the latex particles and located at the water phase.It was considered that SiO2 particles encapsulated(including grafted) with more AN-MMA copolymer were mainly located at the internal of the composite particles,while the SiO2 particles with few encapsulated(grafted) copolymer were inserted at the surface of the composite particles or dispersed in the water phase.Mesoporous carbon materials were prepared using AN-MMA copolymer as carbon precursors and silica particles as templates via inorganic templating method by carbonization of the composite and etching of the silica template.FT-IR spectroscopy, thermogravimetric analysis,X-ray photoelectron spectroscopy,N2 adsorption-desorption, scan electron microscopy(SEM) and TEM were used to characterize the composition,pore size distribution and the structure of the resulting carbon materials,and the influences of content of SiO2 and temperature on the porours textural parameters were studied.The results showed that silica template could be completely removed after the treatment with hydrofluoric acid.The meso-pores within the carbon particles were mainly originated from the silica template particles.The mesoporous carbons prepared by inorganic templating method exhibitedⅣtype absorption behavior with a hysteresis loop at relatively high pressure(P/P0),indicating the presence of meso-pores.The BET surface area,total pore volume,average pore size,the degree of mesoporosity of mesoporous carbons were greater when AN-MMA copolymer/SiO2 composite particles were carbonized at 800℃The degree of mesoporosity and average pore size of mesoporous carbons was increased with the increase of SiO2 content in composite particles.The degree of mesoporosity of the resulting carbons were about 54.8%,62.7%and 76.6%when the contents of SiO2 in the composite particles were12.24%,19.12%,and 24.93%,respectively,and average pore size were 3.97nm,4.964nm and 7.44nm accordingly.The morphology of mesoporous carbons prepared by SiO2 template was observed by using TEM and SEM,it was showed that the resulted carbons exhibited obvious mesoporous structure,the meso-pores were distributed in carbon matrix in a disordered state.It was confirmed that the method proposed in this thesis was an effective approach to prepare the mesoporous carbon with many uniform meso-pores.
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