【摘要】 试验以预处理的FCC油浆为原料,采用程序升温、多管井式坩埚炉进行热转化形成有序生长中间相反应研究。同时,利用高温光学显微镜连续观察了样品热转化过程中流动对中间相有序生长机理的影响。试验发现,原料高温热转化过程中反应残余物收率在反应初期下降迅速,后期逐渐趋于稳定,数学上表现出指数衰减形式。变径反应管内热聚合反应初期,以中间相的生成、长大为主,且其大小呈非均匀尺度分布。随着体系中间相的生长、含量增加以及黏度的升高,上升气流的引导作用促进了中间相的有序排列。高温原位观察发现,原料经预处理后样品中含有超细各向异性中间相微晶体,该微晶体的出现进一步促进了后续热聚合过程中中间相的产生与发展。440￣450℃区域适合中间相的形成与生长。此外,在显微镜下观察看到了中间相因表面张力和载气侧吹所产生的位移变化以及位移后所形成的运动轨迹,有力地证实了气流导向作用对中间相有序融并生长的影响。更多还原

【Abstract】 Orderly growth of mesophase was studied using FCC slurry as raw materials, in a multi-tube well-crucible furnace controlled by programmed heating. The thermal decomposition gas flow was continuously observed to see its influence on the mechanism of mesophase orderly growth using a high temperature optical microscope. It is shown that reactant yield was rapidly decreased in the initial reaction stage and tended towards stability gradually on a later reaction stage, and the yield could be represented by an index decay function. The polymerization initial stage was the main period of formulation and growth of mesophase in the pipe of variable diameter, and the size distribution of mesophases was non-uniform. With the growth of mesophase and the increase of its content, the viscosity was also increased in the system. The orderly growth of mesophase was promoted by the single flow of the thermal decomposition gas. In-situ observation shows that there was a little micro-crystal in the raw materials, while it was precisely the superfine anisotropic crystal that further promoted the growth and development of mesophase. The suitable temperature for mesophase growth was in the range of 440~450℃. In addition, the mesophase moving path was observed as in a continuous change in the high temperature optical microscope because of surface tension and the side blowing of N2. That fact further verifies the influence of the flow of gas on orderly growth of mesophase.更多还原