Symmetric azo-bis-mercapto compounds

US4059574A · kind A · utility

Assignee

• Rohm Co., Ltd. · JP

Inventors

• Otto Hitzler · Langen (Hessen), DE
• Horst Pennewiss · Darmstadt, DE
• August Froelich
• Gerhard Markert · Ober-Ramstadt, DE
• Winfried Wunderlich · Roßdorf, DE

Key dates

• Filing date: Apr 20, 1976
• Grant date: Nov 22, 1977
• Expiry date: Apr 20, 1996

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08F4/04
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

Symmetric azo-bis-mercapto compounds of the formula ##STR1## wherein R.sub.1 and R.sub.2 are methyl or ethyl, R.sub.3 and R.sub.4 are the same or different alkylene having 1 to 4 carbon atoms, and n is 0 or 1, and a method for forming block copolymers of vinyl monomers in a two-step process employing such compounds as polymerization initiators.