Synthesis and Characterization of Polyurethane-Based Shape-Memory Polymers for Tailored Tg around Body Temperature for Medical Applications

✍ Scribed by Manzoor Ahmad; Jikui Luo; Bin Xu; Hendra Purnawali; Peter James King; Paul Raymond Chalker; Yongqing Fu; Weimin Huang; Mohsen Miraftab

• Publisher: John Wiley and Sons
• Year: 2011
• Tongue: English
• Weight: 824 KB
• Volume: 212
• Category: Article
• ISSN: 1022-1352
• DOI: 10.1002/macp.201000540

✦ Synopsis

Abstract

Various polyurethane‐based SMPUs were synthesized using five types of polyols as soft segments and two different diisocyanates as hard segments. The effects of diisocyanate concentration on material properties such as crystallinity, transition temperature, shape‐memory effect and tensile strength were investigated. SMPUs with a maximum strain near 1 000%, recovery rate up to ≈98%, fixity up to ≈90% and T~g~s of 35–45 °C were obtained. A high MDI content results in SMPUs with better shape‐memory effect, whereas increasing IPDI content leads to a weaker shape‐memory effect. High IPDI concentration seems to prevent or restrict chemical reactions and crosslinks between the polyols and the hard segments, leading to large phase separation and coexistence of soft and hard segments in the macrophases. magnified image