4D printing of PLA/PCL-based bio-polyurethane via moderate cross-linking to adjust the microphase separation. (21st September 2022)

• Record Type: Journal Article
• Authors: Song, Minzimo; Liu, Xiaoxuan; Yue, Hangbo; Li, Shanji; Guo, Jianwei
• Is Part Of: Polymer. Volume 256(2022)
• Publication Date: 2022-09-21
• Subjects: 4D printing -- Stimulus-responsive polymers -- Cross-linking -- Microphase separation -- Shape memory; Polymers -- Periodicals; Polymerization -- Periodicals; Polymères -- Périodiques; Polymérisation -- Périodiques; 547.7
• DOI: 10.1016/j.polymer.2022.125190
• Languages: English
• ISSNs: 0032-3861

Abstract

Abstract: Bio-polyurethanes with reversible thermal stimulation responsiveness and remarkable mechanical properties are desirable for 4D printed materials. Herein, polylactic acid (PLA)/polycaprolactone (PCL) based bio-polyurethane material (CBPU) showing excellent mechanical property (e.g. elongation at break reached 584%) and shape memory effect was designed and prepared. Moderate cross-linking of the bio-polyurethane using chitooligosaccharide (COS) successfully promoted the formation of a microphase-separated structure between the hard phase composed of isophorone diisocyanate (IPDI) and soft phase consisting of PLA and PCL. In addition, the CBPU changed autonomously between printed and temporary shapes at preset (−5 °C) and physiological (40 °C) temperatures, respectively, with shape recovery ratio >98%. Therefore, a combination of programmable printability, high toughness, and shape memory capability make CBPU very promising for a wide range of applications in bio-tissue engineering, soft robotics, and intelligent sensors. Graphical abstract: Image 1 Highlights: Printable PLA/PCL-based bio-polyurethane with high toughness was prepared for 4D printing model materials. The degree of microphase separation in PLA/PCL-based bio-polyurethane can be adjusted by changing the cross-linking ratios. 4D printed model with thermal stimulation response capability between preset (−5 °C) and physiological (40 °C) temperatures.