中文摘要：

以聚乙二醇-200和聚乙二醇-400为改性剂、对甲苯磺酸为催化剂对煤沥青进行改性，研究改性煤沥青的化学性质、成焦的晶体结构和显微结构。结果表明，改性后的煤沥青口树脂含量提高了51．90％-55．18％，芳核的缩合度和骨架振动吸收频率显著增大；改性反应主要发生在芳环的氢位上。在800℃时的残炭率比未改性煤沥青增加了18％；此外，在低于160℃时，经聚乙二醇-400改性后的煤沥青黏度低于同温度下未改性的煤沥青黏度，而经聚乙二醇-200改性的煤沥青黏度则高于同温度下未改性的煤沥青黏度。经聚乙二醇-200改性的沥青所制半焦纤维组织结构明显改善；其有序性和堆积高度也显著提高。

英文摘要：

Polyethylene glycol-200 and-400 were used to modify coal-tar pitch using p-toluene sulfonic acid as a catalyst. The chemical properties of the modified pitches and the microstructure of the derived cokes were studied. Results showed that the β resin contents were increased by 52-55 wt. %, the residual carbon yield at 800℃ was increased by 18 wt. %, the vibration absorption fre- quency of C=C bond in aromatic rings increased significantly, and the condensation degree was improved after the modification. The modification reactions occurred at the positions of aromatic hydrogen. The viscosities of the pitch modified with PG-400 and-200 are respectively lower and higher than that of the pristine pitch. The fibrous structure of the semi-coke from the PG-200 modified pitch was significantly improved and its degree of ordering and stack height of graphene layers were also increased significantly.