English Abstract

Methanolysis of the Polyurea in Subcritical or Supercritical Carbon Dioxide

Suguru MOTOKUCHO *1
Shingo MUKAI *2
Mutsuhisa FURUKAWA *3
Ken KOJIO *1
Kohji YOSHINAGA *1
*1:Graduate School of Engineering, Nagasaki University, Bunkyo-machi, Nagasaki, Japan
*2:Faculty of Engineering, Nagasaki University, Bunkyo-machi, Nagasaki, Japan
*3:Professor Emeritus, Nagasaki University, Bunkyo-machi, Nagasaki, Japan
Nippon Gomu Kyokaishi,(2012),85(5),157-161 Original Paper in Japanese

Methanolysis of polyurea (PUA) in the subcritical carbon dioxide was investigated. PUA was synthesized from 4,4'-diphenylmethane diisocyanate and water in the N,N-dimethylformamide. The methanolysis were performed in the temperature range from 160 to 190 °C and under supercritical state of carbon dioxide at pressures from 3.5 to 13.8 MPa. The methanolysis of PUA at 190 °C in the pressure range from 4.3 to 7.3 MPa gave methanol soluble products composed of dimethyl-carbamate, diamine and carbamate-amine compounds in 97-99 % conversion.

Keywords: Supercritical Carbon Dioxide, Polyurea, Methanolysis, Recycle