Abstract
In this contribution, shape memory polymers (SMPs) of chemically-crosslinked zwitterionic polyurethanes (CZPUs) were fabricated by crosslinking of the N,N-bis(2-hydroxyethyl) isonicotinamide (BINA)/hexamethylene diisocyanate (HDI) polyurethanes system by using pentaerythritol (PER), followed by zwitterionization with 1, 3-propanesultone (PS). As the zwitterionic units increased, it was found that the glass transition of hard phase in CZPUs remains constant while that of soft phase shifted at lower temperature, and a broad glass transition was obtained. The broad glass transition enables CZPUs to display triple, quadruple, and quintuple shape memory behaviours. Meanwhile, due to the chemically-crosslinked structure, the CZPUs exhibited an excellent shape fixation and recovery. Furthermore, the CZPU also exhibited good moisture-induced shape memory effect (SME) with a fast and high shape recovery observed below 70% RH and at 37 °C. The excellent thermally-induced multi-shape memory effect and moisture-induced shape memory effect enable CZPUs to be applied as smart materials for many applications among them the biomedical fields.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.