Abstract: C5 fraction from ethylene plant contains a large number of linear unsaturated molecules and cyclopentadiene with mass fraction of more than 16%. A light-colored petroleum resin can be obtained from reaction of C5 fraction using BF3 as catalyst. Cyclopentadiene should be first removed when its concentration is high，so the softening point of the resin would not be too high. Using ethylene plant by-product C5 fraction as raw material，the effect of BF3 and AlCl3 mass ratio，catalyst amount，reaction temperature on C5 petroleum resin softening point and yield was investigated. The optimal catalytic activity was attained through mass ratio of boron trifluoride to anhydrous aluminium trichloride 7∶3，mass ratio of catalyst to total raw material 2%，reaction temperature 40 ℃ for 4 h. Under optimal conditions mass yield was 56.6%，chromaticity was 6—7，softening point was 101 ℃. The light-colored C5 petroleum resin can be directly used in printing ink and rubber.

Key words: ethylene, petroleum resin, cationic polymerization, aluminium chloride, boron trifluoride

摘要： 裂解乙烯C5馏分含有大量线性不饱和分子和质量分数超过16%的环戊二烯，用BF3做催化剂可以得到浅色石油树脂，但当环戊二烯含量高时一般需先除去，得到的树脂软化点不是很高。本文以乙烯装置副产Ｃ5馏分为原料，考察了BF3与AlCl3质量比、催化剂用量、反应温度对Ｃ5石油树脂软化点及收率的影响。实验结果表明，三氟化硼和无水三氯化铝最佳质量比为7∶3，催化剂总用量占原料总质量的2%，在反应温度为40 ℃，反应时间为4 h时，可得到收率为56.6%（质量分数），色度为6～7，软化点为101 ℃的浅色C5石油树脂，其直接可用于油墨、橡胶等中。

关键词: 乙烯, 石油树脂, 阳离子聚合反应, 三氯化铝?, 三氟化硼