材料期刊网

用KH-550对氧化石墨进行改性,再对其进行还原,获得功能化石墨烯（FG）,未经干燥的FG经超声处理后可以稳定分散在质量比9∶1的丙酮/水混合液中;在高速搅拌和超声分散条件下,将FG分散液分散到室温硫化（RTV）硅橡胶中,固化后得到纳米FG（nano-FG）/RTV硅橡胶复合材料。采用FTIR、TEM、SEM、XRD和DSC分析了FG及复合材料的结构和形貌。结果表明：KH-550连接到石墨烯片层表面上,使其片层起皱、折叠,部分发生了剥离,层间距增大到3.46A°;FG经过超声处理后剥离成透明至半透明的片层;nano-FG/RTV硅橡胶复合材料的断面结构为褶皱结构,不同于纯硅橡胶,也未出现微观相分离;与硅橡胶相比,复合材料的Tg、Tm和结晶度均有所提高。复合材料的力学性能测试结果表明,nano-FG对RTV硅橡胶具有明显的补强效果,当nano-FG质量分数为0.5%时,nano-FG/RTV硅橡胶复合材料的拉伸强度比纯RTV硅橡胶提高了一倍多,达到了0.43 MPa;断裂伸长率也提高了52%,达到了265%。

Graphite oxide was modified by KH-550,the modified graphite oxide was reduced to form functionalized graphene（FG） dispersing consistently in the acetone/water（mass ratio is 9∶1） solution by ultrasonic treatment before drying.The FG dispersion was intensively mixed for a certain time by ultrasonic treatment to disperse the nano-FG in α,ω-dihydroxy polydimethylsiloxane matrix and obtained an uniform and stable nano-FG/room temperature vulcanized（RTV） silicone rubber composite after curing.FTIR,TEM,SEM,XRD,and DSC analysis show that KH-550 bonds to the surface of FG sheet to make its layers wrinkled,folding and partially exfoliated,and broaden its layer spacing to 3.46.FG exfoliates into transparent or semi-transparent layers after ultrasonic treatment.The uniform and wrinkled cross-section morphology of nano-FG/RTV silicone rubber composite,which is different from that of pure silicone rubber,shows that there is no micro-phase separation between the two parts.Compared with the pure silicone rubber,the Tg,Tm and crystallinity of all the nano-FG/RTV silicone rubber composites are improved.Mechanical property tests show that nano-FG reinforces silicone rubber a lot.The tensile strength and the elongation at break of composite with 0.5wt% nano-FG are 0.43MPa and 265%,respectively.The tensile strength more than doubles and the elongation at break increases 52% compared with that of pure silicone rubber.