Processing of acrylic hotmelts by reactive extrusion

US6753079B2 · kind B2 · utility

Assignee

• tesa AG · DE

Inventors

• Marc Husemann · Hamburg, DE
• Stephan Zollner · Hamburg, DE

Key dates

• Filing date: Jun 12, 2002
• Grant date: Jun 22, 2004
• Expiry date: Jun 12, 2022

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T428/31938
• WIPO field: Basic materials chemistry
• WIPO sector: Chemistry

Abstract

A process for preparing polyacrylic hotmelt pressure sensitive adhesives, which comprises the following steps:(a) compoundingan acrylic hotmelt pressure sensitive adhesive containing at least one functional group X, having a solvent content of not more than 0.5% by weight and a molecular mass MW of from 100,000 to 2,000,000 g/mol,with at least one chemical substance R—Y containing at least one functional group Y, said at least one functional group X and said at least one functional group Y being chosen such that they are capable of undergoing a coupling reaction with one another,(b) treating the compound in a reactor with a mixing apparatus at a specific drive energy of not more than 0.09 kWh/kg and at a temperature of from 80 to 200° C.,(c) transferring the self-adhesive composition thus treated to a downstream coating unit, and applying it from the melt to a backing material.