Process for the preparation of copolyphosphonates having high toughness

US4719279A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Hermann Kauth · Krefeld, DE
• Klaus Reinking · Wermelskirchen, DE
• Dieter Freitag · Krefeld, DE

Key dates

• Filing date: May 30, 1986
• Grant date: Jan 12, 1988
• Expiry date: May 30, 2006

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08G79/04
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

Polyester-phosphonates, polycarbonatophosphonates and polyester-carbonatophosphonates having improved impact strength and notched impact strength as compared with melt-condensation products can be prepared in such a way that, in the first stage, oligophosphonates with hydroxyl end groups are prepared by melt-transesterification and melt-condensation and these are subjected in a second stage to a phase boundary process.