Shape memory and nanostructure in poly(norbornyl-POSS) copolymers

• Published in: Polymer international Vol. 49; no. 5; pp. 453 - 457
• Main Authors: Jeon, H G, Mather, P T, Haddad, T S
• Format: Journal Article
• Language: English
• Published: Chichester, UK John Wiley & Sons, Ltd 01-05-2000
• Subjects: nanocomposite; polynorbornene; POSS; shape-memory polymer
• ISSN: 0959-8103; 1097-0126
• DOI: 10.1002/(SICI)1097-0126(200005)49:5<453::AID-PI332>3.0.CO;2-H

The microstructure and shape‐memory properties of norbornyl–POSS hybrid copolymers having either cyclohexyl corner groups (CyPOSS) or cyclopentyl corner groups (CpPOSS) were investigated by transmission electron microscopy and thermomechanical analysis. Here, POSS refers to the polyhedral oligomeric silsesquioxane macromer. Samples containing 50 wt% of POSS macromer have been mechanically drawn at temperatures above their glass transition temperatures, followed by rapid quenching in LN2. Shape‐memory properties of such drawn samples were explored by measuring recovered strain while heating above the Tg using thermomechanical analysis. Incorporation of POSS comonomers within PN is found to slightly reduce the percentage recovery, while improving thermal stability significantly. Interestingly, the types of corner groups in the POSS macromer affect the shape‐memory behaviour, with the CyPOSS copolymer showing lower percentage recovery than the CpPOSS copolymer due to enhanced aggregation of CyPOSS macromers.
© 2000 Society of Chemical Industry