Polycarbonate having a low shear thinning behavior

US6699959B2 · kind B2 · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• James P. Mason · Robinson Township, US
• Silke Kratschmer · Krefeld, DE
• Uwe Hucks · Alpen, DE

Key dates

• Filing date: Mar 22, 2002
• Grant date: Mar 2, 2004
• Expiry date: Mar 22, 2022

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08G64/307
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

A melt-polymerized polycarbonate is disclosed. The polycarbonate has a shear thinning ratio (y) that is defined by the limiting values of the following equationc+axb>y>−c+axb  (Q)wherein y≧1, c=0.3 to 0.1, b=14.831±0.05 to 0.02, a=0.1262±0.005 to 0.003 and x is the relative viscosity of the polycarbonate. The polycarbonate exhibits a flow behavior similar to that of a linear polycarbonate of comparable molecular weight obtained by the interface polymerization process.