The influence of hard-segments on two-phase structure and shape memory properties of PCL-based segmented polyurethanes

2007 ◽  
Vol 45 (5) ◽  
pp. 557-570 ◽  
Author(s):  
Peng Ping ◽  
Wenshou Wang ◽  
Xuesi Chen ◽  
Xiabin Jing
Keyword(s):  
Shape Memory ◽  
Phase Structure ◽  
Two Phase ◽  
Shape Memory Properties ◽  
Hard Segments ◽  
Segmented Polyurethanes

scholarly journals Shape-Memory Properties of Segmented Polymers Containing Aramid Hard Segments and Polycaprolactone Soft Segments

Polymers ◽  
2010 ◽  
Vol 2 (2) ◽  
pp. 71-85 ◽  
Author(s):  
Christian Schuh ◽  
Kerstin Schuh ◽  
Maria C. Lechmann ◽  
Louis Garnier ◽  
Arno Kraft
Keyword(s):  
Shape Memory ◽  
Soft Segments ◽  
Shape Memory Properties ◽  
Hard Segments

scholarly journals The Effect of 4-Octyldecyloxybenzoic Acid on Liquid-Crystalline Polyurethane Composites with Triple-Shape Memory and Self-Healing Properties

2016 ◽  
Author(s):  
Jianfeng Ban ◽  
Linjiang Zhu ◽  
Shaojun Chen ◽  
Yiping Wang
Keyword(s):  
Shape Memory ◽  
Liquid Crystalline ◽  
Crystallization Rate ◽  
Self Healing ◽  
Two Phase ◽  
Structure Morphology ◽  
Shape Memory Properties ◽  
Triple Shape Memory ◽  
Polyurethane Composites ◽  
Shape Memory Polyurethane

To better understand the shape memory materials and self-healing materials, a new series of liquid-crystalline shape memory polyurethane (LC-SMPU) composites, named SMPU-OOBAm, were successfully prepared by incorporating 4-octyldecyloxybenzoic acid (OOBA) into the PEG-based SMPU. The effect of OOBA on the structure, morphology and properties has been carefully investigated. The results demonstrate that SMPU-OOBAm have liquid crystalline properties, triple-shape memory properties and self-healing properties. The incorporated OOBA promotes the crystallizability of both soft and hard segments of SMPU, and the crystallization rate of the hard segment of SMPU decreases when the OOBA-content increases. Additionally, the SMPU-OOBAm forms a two-phase separated structure (SMPU phase and OOBA phase), and it shows two-step modulus changes upon heating. Therefore, the SMPU-OOBAm shows triple-shape memory behavior, and the shape recovery ratio decreases with an increase in the OOBA content. Finally, SMPU-OOBAm shows self-healing properties. The new mechanism can be ascribed to the heating-induced “bleeding” of OOBA in the liquid crystalline state and the subsequent re-crystallization upon cooling. This successful combination of liquid crystalline properties, triple-shape memory properties and self-healing properties make the SMPU-OOBAm composites with many promise applications in smart optical devices, smart electronic devices and smart sensors.

Polydimethylsiloxane-Based Polyurethanes: Phase-Separated Morphology and In Vitro Oxidative Biostability

2009 ◽  
Vol 62 (8) ◽  
pp. 794 ◽  
Author(s):  
Taeyi Choi ◽  
Jadwiga Weksler ◽  
Ajay Padsalgikar ◽  
Rebeca Hernéndez ◽  
James Runt
Keyword(s):  
Segmented Polyurethane ◽  
Two Phase ◽  
Dimethyl Siloxane ◽  
X Ray Scattering ◽  
Soft Segments ◽  
Hard Segments ◽  
Segmented Polyurethanes ◽  
Methylenediphenyl Diisocyanate ◽  
End Group

Three series of segmented polyurethane block copolymers were synthesized using 4,4′-methylenediphenyl diisocyanate (MDI) and 1,4-butanediol (BDO) or 1,3-bis(4-hydroxybutyl)tetramethyl disiloxane (BHTD) as the hard segments, and soft segments composed of poly(dimethyl siloxane) (PDMS)-based and poly(hexamethylene oxide) (PHMO) macrodiols. Copolymers synthesized with the PDMS macrodiol and PDMS and PHMO macrodiol mixtures consist of three microphases: a PDMS phase, hard domains, and a mixed phase of PHMO (when present), PDMS ether end-group segments and some dissolved hard segments. Degrees of phase separation were characterized using small-angle X-ray scattering by applying a pseudo two-phase model, and the morphology resulting from unlike segment demixing was found to be closely related to the in vitro oxidative biostability of these segmented polyurethanes.

scholarly journals Shape-memory properties of electrospun non-woven fabrics prepared from degradable polyesterurethanes containing poly(ω-pentadecalactone) hard segments

2012 ◽  
Vol 48 (11) ◽  
pp. 1866-1874 ◽  
Author(s):  
Hidetoshi Matsumoto ◽  
Tasuku Ishiguro ◽  
Yuichi Konosu ◽  
Mie Minagawa ◽  
Akihiko Tanioka ◽  
...  
Keyword(s):  
Shape Memory ◽  
Woven Fabrics ◽  
Shape Memory Properties ◽  
Hard Segments

scholarly journals Shape-memory Nanofiber Meshes with Programmable Cell Orientation

2018 ◽  
Author(s):  
Eri Niiyam ◽  
Kanta Tanabe ◽  
Koichiro Uto ◽  
Akihiko Kikuchi ◽  
Mitsuhiro Ebara
Keyword(s):  
Shape Memory ◽  
Shape Memory Effect ◽  
Memory Effect ◽  
Rational Design ◽  
Hexamethylene Diisocyanate ◽  
Molar Ratio ◽  
Original Structure ◽  
Cell Functions ◽  
Shape Memory Properties ◽  
Hard Segments

This paper reports a rational design of temperature-responsive nanofiber meshes with shape-memory effect. The meshes were fabricated by electrospinning a poly(ε-caprolactone) (PCL)-based polyurethane with different contents of soft and hard segments. The effects of PCL diol/hexamethylene diisocyanate (HDI)/1,4-butanediol (BD) molar ratio in terms of the contents of soft and hard segments on the shape-memory properties were investigated. Although the mechanical property improved with increasing hard segment ratio, optimal shape-memory properties were obtained with a PCL/HDI/BD molar ratio of 1:4:3. At a microscopic level, the original nanofibrous structure was easily deformed into a temporary shape, and recovered its original structure when the sample was reheated. A higher recovery rate (>89%) was achieved even when the mesh was deformed up to 400%. Finally, the nanofiber meshes were used to control the alignment of human mesenchymal stem cells (hMSCs). The hMSCs aligned well along the fiber orientation. The proposed nanofibrous meshes with the shape-memory effect have the potential to serve as in vitro platforms for the investigation of cell functions as well as implantable scaffolds for wound-healing applications.

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