Reversibly switchable cross-linking of monomers

US6469134B2 · kind B2 · utility

Assignee

• Daimlerchrysler AG · US

Inventors

• Hermann Gaub · Jessenitz Siedlung, DE
• Andreas Mittelbach · Unterhaching, DE
• Peter Jaenker · Garching bei München, DE
• Felix Nitschke · Munich, DE
• Ulrich Schubert · Jena, DE

Key dates

• Filing date: Jan 22, 2001
• Grant date: Oct 22, 2002
• Expiry date: Jan 22, 2021

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08G61/122
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

A method for reversibly switchable cross-linking of monomers includes cross-linking the monomers by adding complexable metal ions to form a polymer, and bond-breaking the polymer formed by applying a direct voltage, by changing the pH value or by changing the temperature. The monomers include compounds of the general formulas R1 through R6 may be equal or different and are selected from the group consisting of H, OH, —NX2, —OX, —SH, and —SX, with X being selected from alkyl and/or aryl groups which are terminally substituted by reactive residues selected from the group consisting of OH, —CH(O)CH2, —NCO, —COOH and NZ2. Z is selected from the group consisting of alkyl groups, aryl groups and a hydrogen atom, one of the groups Z being a hydrogen atom with the proviso that not all residues R1 through R are hydrogen atoms at the same time. Repeated cross-linking of the bond-broken polymer may be carried out by applying a direct voltage opposite in polarity to the direct voltage of the bond-breaking step, by changing the pH value, or by changing the temperature.