title: Chemical cross-linking of polypropylenes towards new shape memory polymers.
abstract: In this work, syndiotactic polypropylene (sPP) as well as isotactic polypropylene (iPP) are cross-linked to gain a shape memory effect. Both prepared PP networks exhibit maximum strains of 700%, stored strains of up to 680%, and recoveries of nearly 100%. While x-iPP is stable for many cycles, x-sPP ruptures after the first shape-memory cycle. It is shown by wide-angle X-ray scattering (WAXS) experiments that cross-linked iPP exhibits homoepitaxy in the temporary, stretched shape but in contrast to previous reports it contains a higher amount of daughter than mother crystals.
authors.affiliation: Biomaterials and Polymer Science, Department of Biochemical and Chemical Engineering, TU Dortmund, 44221, Dortmund, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Raidt
authors.forename: Robin
authors.initials: R
authors.lastname: Hoeher
authors.forename: Frank
authors.initials: F
authors.lastname: Katzenberg
authors.forename: Joerg C
authors.initials: JC
authors.lastname: Tiller
mesh_terms: D003432:Cross-Linking Reagents / Q000737:chemistry*; D010316:Particle Size; D058105:Polymerization; D011108:Polymers / Q000737:chemistry*; D011126:Polypropylenes / Q000737:chemistry*; D012542:Scattering, Radiation; D013696:Temperature; D014965:X-Rays
chemical_list: D003432:Cross-Linking Reagents; D011108:Polymers; D011126:Polypropylenes
keywords: cross-linking; isotactic; polypropylenes; shape-memory polymers; syndiotactic