煤沥青及其改性后中间相的转化行为研究

STUDY ON THE MEASOPHASE TRANSFORMATIONS OF COAL TAR PITCH AND MODIFIED COAL TAR PITCH

以煤沥青(CTP)和改性沥青(MCTP)为原料,在氮气保护下,采用热聚合的方法,制备出两种中间相沥青(MPPA和MPPB),采用FTIR与热分析对CTP与MCTP的中间相转化行为进行了研究.通过偏光显微镜分析,MPPA为镶嵌结构,MPPB为流域结构,对两种中间相沥青进行XRD分析,发现MPPB比MPPA具有较好的晶态结构.

Two kinds of mesophase pitches （MPP） were prepared by heat-treatment two coal tar pitches （CTP） and modified coal tar pitch （MCTP） in the presence of nitrogen. The pyrolysis behaviors of CTP and MCTP were studied by means of thermal analysis （TG and DSC）. The morphologies of MPP were inspected by optical microscope. The structures of the MPP were characterized by XRD. The results show that there are more alkyl functional groups existing in CTP and MCTP than in MPP, which indicate MPP formation predominantly polycondense aromatic and release the alkyl functional groups. An endotherrnic band due to volatilize light compounds around 290 ℃, two exothermic peaks at the range of 400 ℃-500 ℃ were characteristic of polymerization reactions, exothermic peaks of MCTP is higher than that of CTP because the former have a higher reaction active for its more alkyl side chain. MPP from CTP is mosaics texture, while from the MCTP is flow domains texture, （002） and （101） peaks of graphite occur on XRD patterns, the peaks of MPP from MCTP is higher and narrower than MPP from CTP, which indicates the former is more graphitizability than the latter.