The influence of liquid crystals on the properties of sisal fibre polyurethanes with multi-shape memory effects

2019 ◽  
Vol 43 (7) ◽  
pp. 3111-3118 ◽  
Author(s):  
Lulu Pan ◽  
Jianfeng Ban ◽  
Li Ren ◽  
Zuocai Zhang ◽  
Qingyuan Peng ◽  
...  
Keyword(s):  
Liquid Crystals ◽  
Shape Memory ◽  
Memory Effects ◽  
Sisal Fibre ◽  
Shape Memory Properties ◽  
Shape Memory Effects

LC-SF-SMPUs show excellent multi-shape memory properties.

Study on Shape Memory Effects of LC Epoxy Resins with Lateral Substituents

2010 ◽  
Vol 428-429 ◽  
pp. 391-393 ◽  
Author(s):  
Li Yan Liang ◽  
De Wen Zhou ◽  
Man Geng Lu
Keyword(s):  
Shape Memory ◽  
Dynamic Mechanical Analysis ◽  
Epoxy Resins ◽  
Liquid Crystalline ◽  
Mechanical Analysis ◽  
Memory Effects ◽  
Ordered Structures ◽  
Alkyl Groups ◽  
Shape Memory Properties ◽  
Shape Memory Effects

A series of shape memorized liquid crystalline epoxides with different length of lateral substituents were prepared with several kinds of hardener. The dynamic mechanical analysis and the sharp memory properties of the resulted LC epoxy resins were studied by POM, WAXD, DSC and DMA. The results showed that the modulus in the rubbery region (ER) of the LC epoxides decreases as the length of lateral alkyl groups increases. And the shape memory properties were strongly impacted not only by the length of lateral substituents, but also by the kinds of hardener. The recovering speeds of the shape-memory liquid crystalline epoxides decrease as the increasing length of lateral alkyl groups. And recovering speeds of LC epoxides cured with aromatic amine (DDM) are faster than that of LC epoxides cured with anhydride (THHPA). The local ordered structures and the lateral substituents played an important role in shape memory effects.

Development of zwitterionic polyurethanes with multi-shape memory effects and self-healing properties

2015 ◽  
Vol 3 (6) ◽  
pp. 2924-2933 ◽  
Author(s):  
Shaojun Chen ◽  
Funian Mo ◽  
Yan Yang ◽  
Florian J. Stadler ◽  
Shiguo Chen ◽  
...  
Keyword(s):  
Shape Memory ◽  
Memory Effects ◽  
Hexamethylene Diisocyanate ◽  
Self Healing ◽  
Shape Memory Properties ◽  
Shape Memory Effects

Novel zwitterionic polyurethanes containing sulfobetaines, featuring excellent multi-shape-memory properties and self-healing properties, are prepared from N-methyldiethanolamine, hexamethylene diisocyanate and 1,3-propanesultone.

Development of liquid crystalline polyurethane composites with stage-responsive shape memory effects

2018 ◽  
Vol 9 (5) ◽  
pp. 576-583 ◽  
Author(s):  
Shaojun Chen ◽  
Jianfeng Ban ◽  
Luona Mu ◽  
Haitao Zhuo
Keyword(s):  
Shape Memory ◽  
Polymer Composites ◽  
Liquid Crystalline ◽  
Shape Memory Polymer ◽  
Memory Effects ◽  
Shape Memory Properties ◽  
Shape Memory Effects ◽  
Polyurethane Composites

Novel liquid crystalline shape memory polymer composites with interesting staging-responsive shape memory properties were successfully prepared. The liquid crystalline shape memory polymer composites maintain the intrinsic reversible liquid crystalline properties of Azo11.

scholarly journals Harnessing reversible dry adhesion using shape memory polymer microparticles

RSC Advances ◽  
2021 ◽  
Vol 11 (32) ◽  
pp. 19616-19622
Author(s):  
Wenbing Li ◽  
Junhao Liu ◽  
Wanting Wei ◽  
Kun Qian
Keyword(s):  
Shape Memory ◽  
Shape Memory Polymer ◽  
Shape Memory Polymers ◽  
Memory Effects ◽  
Reversible Adhesion ◽  
Dry Adhesion ◽  
Bonding Property ◽  
Shape Memory Effects ◽  
Polymer Microparticles

Shape memory polymers can provide excellent bonding property because of their shape memory effects. This paper proposes an adhesive unit that is capable of repeatable smart adhesion and exhibits reversible adhesion under heating.

Multi-shape-memory effects in a wavelength-selective multicomposite

2015 ◽  
Vol 3 (26) ◽  
pp. 13953-13961 ◽  
Author(s):  
Li Yu ◽  
Qian Wang ◽  
Jian Sun ◽  
Chenyue Li ◽  
Cheng Zou ◽  
...  
Keyword(s):  
Shape Memory ◽  
Memory Effects ◽  
Shape Memory Effects

Tuneable shape-memory effects can be achieved in a wavelength-selective multicomposite.

A strengthening approach for damping property and shape memory property of acrylic rubber/polylactide blends

2018 ◽  
Vol 51 (7-8) ◽  
pp. 626-643
Author(s):  
Chengliang Li ◽  
Xingxing Ji ◽  
Yang Lyu ◽  
Xinyan Shi
Keyword(s):  
Shape Memory ◽  
Loss Factor ◽  
Phenol Formaldehyde ◽  
Mechanical Analysis ◽  
Damping Properties ◽  
Shape Memory Property ◽  
Memory Property ◽  
Damping Material ◽  
Shape Memory Properties ◽  
Shape Memory Effects

In this work, a damping material was successfully prepared by blending acrylic rubber (ACM) and polylactide (PLA) with sulfur and soap salt as the curing agents. A phenol-formaldehyde (PF) resin was used as a modifier. The effects of PF on the mechanical properties, damping properties, compatibility and shape memory properties of the blends were studied. The compatibility and damping properties were characterized by dynamic mechanical analysis, Fourier transform infrared spectroscope and microstructure analysis. The shape memory properties were examined by thermal mechanical analyser. The results revealed that the tensile strength of the blends was decreased and the toughness was increased with the increase of PF loadings. The introduction of PF improved the compatibility between PLA and ACM, which was deduced from the fact that the glass transition temperature of ACM was increased and the two loss factor peaks became closer. It was also found that the loss factor peak became higher and the effective damping temperature range became wider due to the formation of hydrogen bonding, implying that the damping properties of ACM/PLA blends were significantly improved. The ACM/PLA blends exhibited good dual-shape memory effect and its shape recovery ratio was increased by introduction of PF and raising the trigger temperature. The blends also exhibited good triple-shape memory property, which was dramatically improved by the introduction of PF. The mechanisms for the enhanced shape memory effects were then analysed.

Polyurethane foam/silica chemical hybrids for shape memory effects

2012 ◽  
Vol 27 (22) ◽  
pp. 2837-2843 ◽  
Author(s):  
S.M. Kang ◽  
M.J. Kim ◽  
S.H. Kwon ◽  
H. Park ◽  
H.M. Jeong ◽  
...  
Keyword(s):  
Shape Memory ◽  
Polyurethane Foam ◽  
Memory Effects ◽  
Shape Memory Effects ◽  
Image Position

Abstract

scholarly journals Epoxy Resin Composite Bilayers with Triple-Shape Memory Effect

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Xixi Li ◽  
Yaofeng Zhu ◽  
Yubing Dong ◽  
Meng Liu ◽  
Qingqing Ni ◽  
...  
Keyword(s):  
Glass Transition ◽  
Electron Microscope ◽  
Shape Memory ◽  
Memory Effects ◽  
Epoxy Composites ◽  
Transition Temperatures ◽  
Glass Transition Temperatures ◽  
Shape Memory Effects ◽  
Triple Shape Memory ◽  
Nanosilica Particles

Triple-shape memory epoxy composites with bilayer structures of well-separated glass transition temperatures have been successfully prepared. The different glass transition temperatures of the epoxy composites were obtained by physically incorporating various amounts of nanosilica particles, which were introduced into the epoxy by utilizing polyethylene glycol. A scanning electron microscope and a transmission electron microscope were used to analyze the dispersibility of the nanosilica particles. The effects of nanosilica particles on the mechanical properties as well as on the dual-shape memory effects (DSME) and triple-shape memory effects (TSME) of the nanocomposites were studied. The nanosilica particles were homogenously dispersed in the matrix and well incorporated into the epoxy matrix. The resulting nanocomposites exhibited excellent TSME, and their shape fixity properties were significantly improved by nanosilica particles.

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