Process for production of water-soluble carbodiimide
AssigneeResearch Association for Utilization of Light Oil
InventorsTakahiro Yoneyama, Masaki Odagiri, Makoto Imanari
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Abstract
A process for the production of a water-soluble carbodiimide, which comprises (1) allowing ethyl isothiocyanate to react with N,N-dimethyl-1,3-propanediamine in an aromatic hydrocarbon solvent (first reaction step), (2) removing hydrogen sulfide from a thiourea derivative formed in the first reaction step upon adding a hydrogen sulfide removing agent without isolating the thiourea derivative (second reaction step), and (3) recovering a water-soluble carbodiimide from the resulting reaction mixture.
Claims10
A process for the production of water-soluble carbodiimide, which comprises
- (1) allowing ethyl isothiocyanate to react with N,N-dimethyl-1,3-propanediamine in an aromatic hydrocarbon solvent selected from the group consisting of benzene, toluene and a mixture thereof (first reaction step),
- (2) removing hydrogen sulfide from a thiourea derivative formed in the first reaction step by adding a hydrogen sulfide removing agent selected from the group consisting of a lead oxide, a copper oxide and a mixture thereof and heating at a temperature of about 50.degree. C. to a reflux temperature without isolating the thiourea derivative (second reaction step), and
- (3) recovering the water-soluble carbodiimide from the resulting reaction mixture.
A process for the production of a water-soluble carbodiimide, which comprises
- (1) allowing ethyl isothiocyanate to react with N,N-dimethyl-1,3-propanediamine in an aromatic hydrocarbon solvent selected from the group consisting of benzene, toluene and a mixture thereof (first reaction step),
- (2) removing hydrogen sulfide from a thiourea derivative formed in the first reaction step by adding a hydrogen sulfide removing agent selected from the group consisting of red lead (Pb.sub.3 O.sub.4) and lead dioxide (PbO.sub.2) and heating at a temperature of about 80.degree. C. to 110.degree. C. without isolating the thiourea derivative (second reaction step), and
- (3) recovering the water-soluble carbodiimide from the resulting reaction mixture.
Dependencies are inferred from the claim text.