由芳香族聚酯LCP废弃物回收4,4′-联苯二酚

Preparation of 4, 4′-biphenol from the waste LCP by hydrolysis process

摘要:

本文以1,4-二氧六环为溶剂，NaOH为催化剂，对废弃的含4, 4′-联苯二酚(BP)单元的芳香族聚酯型液晶高分子(LCP) ，在常压下通过水解反应回收制备4, 4′-联苯二酚进行了研究。在反应混合物的质量比m (LCP): m (溶剂): m (H2O): m (NaOH)=1: 4: 1.5: 0.6的最优条件下，液晶高分子的水解率达97%以上。通过在水解液中加入HCl并控制其pH在8.5，可以沉淀得到4, 4′-联苯二酚。4, 4′-联苯二酚经水洗、干燥、甲醇重结晶后，液相色谱检测其纯度可达99.9%，从废弃液晶高分子中制备4, 4′-联苯二酚的收率为70%。

Abstract:

In this paper, 4, 4′-biphenol (BP) was prepared from waste LCP(PHBA- BP- PTA terpolymer)by hydrolysis process under atmospheric pressure using NaOH as catalyst, 1,4-dioxane and water as solvent.The effects of catalyst and solvent on hydrolysis reaction were studied. Under the optimum condition of reaction temperature 100˚C, reaction time 8 h and ratio of reaction mixture: m (LCP): m (solvent): m (H2O): m (NaOH) =1:4:1.5:0.6, the hydrolysis efficiency of the LCP is over 97%. With addition of HCl in the hydrolysate until pH=8.5, BP precipitation was formed. After BP was washed with water, dried and recrystallized in methanol, its purity could reach 99.9%. The yield of BP from the LCP is 70%.