Method for programming a shape memory polymer while defining the switch temperature by selection of the programming temperature

US8926884B2 · kind B2 · utility

Assignee

• Helmholtz-Zentrum Geesthacht Zentrum für Material- und Küstenforschung GmbH

Inventors

• Karl Kratz · Berlin, DE
• Andreas Lendlein · Berlin, DE
• Ulrike Voigt · Hamburg, DE
• Wolfgang Wagermaier · Potsdam, DE

Key dates

• Filing date: Apr 22, 2011
• Grant date: Jan 6, 2015
• Expiry date: Jun 5, 2032

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B29K2067/00
• WIPO field: Other special machines
• WIPO sector: Mechanical engineering

Abstract

The invention relates to a method for programming a shape memory polymer, which comprises at least one switching segment having at least one thermal phase transition and covalent and/or non-covalent cross-linking points such that the shape memory polymer after the programming thereof is in a position to transition from a programmed temporary shape into the permanent shape thereof, following a temperature increase to a temperature that at least corresponds to a switching temperature (Tswitch, Tσmax). According to the invention, the method comprises (a) predetermining a programming temperature (tprog) as a function of a desired switching temperature (Tswitch, Tσmax), (b) heating the shape memory polymer to the predetermined programming temperature (tprog), and transferring the polymer into a shape that corresponds to the temporary shape by applying a forced molding state, and (c) cooling the polymer to a temperature below the desired switching temperature (Tswitch, Tσmax) while maintaining the forced molding state.