Journal of South China University of Technology (Natural Science Edition) ›› 2008, Vol. 36 ›› Issue (3): 12-15.

• Chemistry & Chemical Engineering • Previous Articles     Next Articles

Separation of Toluene Diisocyanate from Curing Agent of Polyurethane via Thin-Film Evaporation

Hu Xiao-yong  Guo Si-yuan  Chen Huan-qin   

  1. Postdoctoral Station of Light Industry Technology and Engineering, South China University of Technology,Guangzhou 510640, Guangdong, China
  • Received:2007-04-20 Revised:2007-07-19 Online:2008-03-25 Published:2008-03-25
  • Contact: 胡孝勇（1971-），男，副教授，博士，主要从事精细化工的研究． E-mail:hxy_pym@sohu．com
  • About author:胡孝勇（1971-），男，副教授，博士，主要从事精细化工的研究．
  • Supported by:

    中国博士后科学基金资助项目（20060400760）;广西工学院博士科研启动基金资助项目

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Abstract:

The free toluene diisocyanate （TDI） in the curing agent TDI-TMP （Trimethylol Propane） of polyure-thane was separated in laboratory by means of high-vacuum two-stage thin-film evaporation. The corresponding pi lot-scale investigation was then performed to analyze the effects of feeding flow and evaporation temperature on the separation efficiency. The results show that, when the separation is performed with a feeding flow of 25 kg/h, a first-stage evaporation pressure of 5000 Pa at 130 ℃ and a second-stage evaporation pressure of 80 Pa at 180 ℃, the content of free TDI in the separated curing agent is less than 0.5%, and the solid and NCO contents are respectively more than 75% and 11.8%, meaning that the free TDI is effectively separated.

Key words: free toluene diisoeyanate, thin-film evaporation, curing agent, polyurethane